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  • How to solve programming problems using logic? [closed]

    - by md nth
    I know these principles: Define the constrains and operations,eg constrains are the rules that you cant pass and what you want determined by the end goal, operations are actions you can do, "choices" . Buy some time by solving easy and solvable piece. Halving the difficulty by dividing the project into small goals and blocks. The more blocks you create the more hinges you have. Analogies which means : using other code blocks, yours or from other programmers . which has problem similar to the current problem. Experiments not guessing by writing "predicted end" code, in other word creating a hypothesis, about what will happen if you do this or that. Use your tools first, don't begin with a unknown code first. By making small goals you ll not get frustrated. Start from smallest problem. Are there other principles?

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  • Difficult to replicate objects (object Customer) on the list? [migrated]

    - by gandolf
    I wrote a program that does work with files like delete and update, store, and search And all customers But I have a problem with the method is LoadAll Once the data are read from the file and then Deserialize the object becomes But when I want to save the list of objects in the list are repeated. How can I prevent the duplication in this code? var customerStr = File.ReadAllLines (address); The code is written in CustomerDataAccess class DataAccess Layer. Project File The main problem with the method LoadAll Code: public ICollection<Customer> LoadAll() { var alldata = File.ReadAllLines(address); List<Customer> lst = new List<Customer>(); foreach (var s in alldata) { var objCustomer = customerSerializer.Deserialize(s); lst.Add(objCustomer); } return lst; }

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  • .NET HTML Sanitation for rich HTML Input

    - by Rick Strahl
    Recently I was working on updating a legacy application to MVC 4 that included free form text input. When I set up the new site my initial approach was to not allow any rich HTML input, only simple text formatting that would respect a few simple HTML commands for bold, lists etc. and automatically handles line break processing for new lines and paragraphs. This is typical for what I do with most multi-line text input in my apps and it works very well with very little development effort involved. Then the client sprung another note: Oh by the way we have a bunch of customers (real estate agents) who need to post complete HTML documents. Oh uh! There goes the simple theory. After some discussion and pleading on my part (<snicker>) to try and avoid this type of raw HTML input because of potential XSS issues, the client decided to go ahead and allow raw HTML input anyway. There has been lots of discussions on this subject on StackOverFlow (and here and here) but to after reading through some of the solutions I didn't really find anything that would work even closely for what I needed. Specifically we need to be able to allow just about any HTML markup, with the exception of script code. Remote CSS and Images need to be loaded, links need to work and so. While the 'legit' HTML posted by these agents is basic in nature it does span most of the full gamut of HTML (4). Most of the solutions XSS prevention/sanitizer solutions I found were way to aggressive and rendered the posted output unusable mostly because they tend to strip any externally loaded content. In short I needed a custom solution. I thought the best solution to this would be to use an HTML parser - in this case the Html Agility Pack - and then to run through all the HTML markup provided and remove any of the blacklisted tags and a number of attributes that are prone to JavaScript injection. There's much discussion on whether to use blacklists vs. whitelists in the discussions mentioned above, but I found that whitelists can make sense in simple scenarios where you might allow manual HTML input, but when you need to allow a larger array of HTML functionality a blacklist is probably easier to manage as the vast majority of elements and attributes could be allowed. Also white listing gets a bit more complex with HTML5 and the new proliferation of new HTML tags and most new tags generally don't affect XSS issues directly. Pure whitelisting based on elements and attributes also doesn't capture many edge cases (see some of the XSS cheat sheets listed below) so even with a white list, custom logic is still required to handle many of those edge cases. The Microsoft Web Protection Library (AntiXSS) My first thought was to check out the Microsoft AntiXSS library. Microsoft has an HTML Encoding and Sanitation library in the Microsoft Web Protection Library (formerly AntiXSS Library) on CodePlex, which provides stricter functions for whitelist encoding and sanitation. Initially I thought the Sanitation class and its static members would do the trick for me,but I found that this library is way too restrictive for my needs. Specifically the Sanitation class strips out images and links which rendered the full HTML from our real estate clients completely useless. I didn't spend much time with it, but apparently I'm not alone if feeling this library is not really useful without some way to configure operation. To give you an example of what didn't work for me with the library here's a small and simple HTML fragment that includes script, img and anchor tags. I would expect the script to be stripped and everything else to be left intact. Here's the original HTML:var value = "<b>Here</b> <script>alert('hello')</script> we go. Visit the " + "<a href='http://west-wind.com'>West Wind</a> site. " + "<img src='http://west-wind.com/images/new.gif' /> " ; and the code to sanitize it with the AntiXSS Sanitize class:@Html.Raw(Microsoft.Security.Application.Sanitizer.GetSafeHtmlFragment(value)) This produced a not so useful sanitized string: Here we go. Visit the <a>West Wind</a> site. While it removed the <script> tag (good) it also removed the href from the link and the image tag altogether (bad). In some situations this might be useful, but for most tasks I doubt this is the desired behavior. While links can contain javascript: references and images can 'broadcast' information to a server, without configuration to tell the library what to restrict this becomes useless to me. I couldn't find any way to customize the white list, nor is there code available in this 'open source' library on CodePlex. Using Html Agility Pack for HTML Parsing The WPL library wasn't going to cut it. After doing a bit of research I decided the best approach for a custom solution would be to use an HTML parser and inspect the HTML fragment/document I'm trying to import. I've used the HTML Agility Pack before for a number of apps where I needed an HTML parser without requiring an instance of a full browser like the Internet Explorer Application object which is inadequate in Web apps. In case you haven't checked out the Html Agility Pack before, it's a powerful HTML parser library that you can use from your .NET code. It provides a simple, parsable HTML DOM model to full HTML documents or HTML fragments that let you walk through each of the elements in your document. If you've used the HTML or XML DOM in a browser before you'll feel right at home with the Agility Pack. Blacklist based HTML Parsing to strip XSS Code For my purposes of HTML sanitation, the process involved is to walk the HTML document one element at a time and then check each element and attribute against a blacklist. There's quite a bit of argument of what's better: A whitelist of allowed items or a blacklist of denied items. While whitelists tend to be more secure, they also require a lot more configuration. In the case of HTML5 a whitelist could be very extensive. For what I need, I only want to ensure that no JavaScript is executed, so a blacklist includes the obvious <script> tag plus any tag that allows loading of external content including <iframe>, <object>, <embed> and <link> etc. <form>  is also excluded to avoid posting content to a different location. I also disallow <head> and <meta> tags in particular for my case, since I'm only allowing posting of HTML fragments. There is also some internal logic to exclude some attributes or attributes that include references to JavaScript or CSS expressions. The default tag blacklist reflects my use case, but is customizable and can be added to. Here's my HtmlSanitizer implementation:using System.Collections.Generic; using System.IO; using System.Xml; using HtmlAgilityPack; namespace Westwind.Web.Utilities { public class HtmlSanitizer { public HashSet<string> BlackList = new HashSet<string>() { { "script" }, { "iframe" }, { "form" }, { "object" }, { "embed" }, { "link" }, { "head" }, { "meta" } }; /// <summary> /// Cleans up an HTML string and removes HTML tags in blacklist /// </summary> /// <param name="html"></param> /// <returns></returns> public static string SanitizeHtml(string html, params string[] blackList) { var sanitizer = new HtmlSanitizer(); if (blackList != null && blackList.Length > 0) { sanitizer.BlackList.Clear(); foreach (string item in blackList) sanitizer.BlackList.Add(item); } return sanitizer.Sanitize(html); } /// <summary> /// Cleans up an HTML string by removing elements /// on the blacklist and all elements that start /// with onXXX . /// </summary> /// <param name="html"></param> /// <returns></returns> public string Sanitize(string html) { var doc = new HtmlDocument(); doc.LoadHtml(html); SanitizeHtmlNode(doc.DocumentNode); //return doc.DocumentNode.WriteTo(); string output = null; // Use an XmlTextWriter to create self-closing tags using (StringWriter sw = new StringWriter()) { XmlWriter writer = new XmlTextWriter(sw); doc.DocumentNode.WriteTo(writer); output = sw.ToString(); // strip off XML doc header if (!string.IsNullOrEmpty(output)) { int at = output.IndexOf("?>"); output = output.Substring(at + 2); } writer.Close(); } doc = null; return output; } private void SanitizeHtmlNode(HtmlNode node) { if (node.NodeType == HtmlNodeType.Element) { // check for blacklist items and remove if (BlackList.Contains(node.Name)) { node.Remove(); return; } // remove CSS Expressions and embedded script links if (node.Name == "style") { if (string.IsNullOrEmpty(node.InnerText)) { if (node.InnerHtml.Contains("expression") || node.InnerHtml.Contains("javascript:")) node.ParentNode.RemoveChild(node); } } // remove script attributes if (node.HasAttributes) { for (int i = node.Attributes.Count - 1; i >= 0; i--) { HtmlAttribute currentAttribute = node.Attributes[i]; var attr = currentAttribute.Name.ToLower(); var val = currentAttribute.Value.ToLower(); span style="background: white; color: green">// remove event handlers if (attr.StartsWith("on")) node.Attributes.Remove(currentAttribute); // remove script links else if ( //(attr == "href" || attr== "src" || attr == "dynsrc" || attr == "lowsrc") && val != null && val.Contains("javascript:")) node.Attributes.Remove(currentAttribute); // Remove CSS Expressions else if (attr == "style" && val != null && val.Contains("expression") || val.Contains("javascript:") || val.Contains("vbscript:")) node.Attributes.Remove(currentAttribute); } } } // Look through child nodes recursively if (node.HasChildNodes) { for (int i = node.ChildNodes.Count - 1; i >= 0; i--) { SanitizeHtmlNode(node.ChildNodes[i]); } } } } } Please note: Use this as a starting point only for your own parsing and review the code for your specific use case! If your needs are less lenient than mine were you can you can make this much stricter by not allowing src and href attributes or CSS links if your HTML doesn't allow it. You can also check links for external URLs and disallow those - lots of options.  The code is simple enough to make it easy to extend to fit your use cases more specifically. It's also quite easy to make this code work using a WhiteList approach if you want to go that route. The code above is semi-generic for allowing full featured HTML fragments that only disallow script related content. The Sanitize method walks through each node of the document and then recursively drills into all of its children until the entire document has been traversed. Note that the code here uses an XmlTextWriter to write output - this is done to preserve XHTML style self-closing tags which are otherwise left as non-self-closing tags. The sanitizer code scans for blacklist elements and removes those elements not allowed. Note that the blacklist is configurable either in the instance class as a property or in the static method via the string parameter list. Additionally the code goes through each element's attributes and looks for a host of rules gleaned from some of the XSS cheat sheets listed at the end of the post. Clearly there are a lot more XSS vulnerabilities, but a lot of them apply to ancient browsers (IE6 and versions of Netscape) - many of these glaring holes (like CSS expressions - WTF IE?) have been removed in modern browsers. What a Pain To be honest this is NOT a piece of code that I wanted to write. I think building anything related to XSS is better left to people who have far more knowledge of the topic than I do. Unfortunately, I was unable to find a tool that worked even closely for me, or even provided a working base. For the project I was working on I had no choice and I'm sharing the code here merely as a base line to start with and potentially expand on for specific needs. It's sad that Microsoft Web Protection Library is currently such a train wreck - this is really something that should come from Microsoft as the systems vendor or possibly a third party that provides security tools. Luckily for my application we are dealing with a authenticated and validated users so the user base is fairly well known, and relatively small - this is not a wide open Internet application that's directly public facing. As I mentioned earlier in the post, if I had my way I would simply not allow this type of raw HTML input in the first place, and instead rely on a more controlled HTML input mechanism like MarkDown or even a good HTML Edit control that can provide some limits on what types of input are allowed. Alas in this case I was overridden and we had to go forward and allow *any* raw HTML posted. Sometimes I really feel sad that it's come this far - how many good applications and tools have been thwarted by fear of XSS (or worse) attacks? So many things that could be done *if* we had a more secure browser experience and didn't have to deal with every little script twerp trying to hack into Web pages and obscure browser bugs. So much time wasted building secure apps, so much time wasted by others trying to hack apps… We're a funny species - no other species manages to waste as much time, effort and resources as we humans do :-) Resources Code on GitHub Html Agility Pack XSS Cheat Sheet XSS Prevention Cheat Sheet Microsoft Web Protection Library (AntiXss) StackOverflow Links: http://stackoverflow.com/questions/341872/html-sanitizer-for-net http://blog.stackoverflow.com/2008/06/safe-html-and-xss/ http://code.google.com/p/subsonicforums/source/browse/trunk/SubSonic.Forums.Data/HtmlScrubber.cs?r=61© Rick Strahl, West Wind Technologies, 2005-2012Posted in Security  HTML  ASP.NET  JavaScript   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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  • jQuery Globalization Plugin from Microsoft

    - by ScottGu
    Last month I blogged about how Microsoft is starting to make code contributions to jQuery, and about some of the first code contributions we were working on: jQuery Templates and Data Linking support. Today, we released a prototype of a new jQuery Globalization Plugin that enables you to add globalization support to your JavaScript applications. This plugin includes globalization information for over 350 cultures ranging from Scottish Gaelic, Frisian, Hungarian, Japanese, to Canadian English.  We will be releasing this plugin to the community as open-source. You can download our prototype for the jQuery Globalization plugin from our Github repository: http://github.com/nje/jquery-glob You can also download a set of samples that demonstrate some simple use-cases with it here. Understanding Globalization The jQuery Globalization plugin enables you to easily parse and format numbers, currencies, and dates for different cultures in JavaScript. For example, you can use the Globalization plugin to display the proper currency symbol for a culture: You also can use the Globalization plugin to format dates so that the day and month appear in the right order and the day and month names are correctly translated: Notice above how the Arabic year is displayed as 1431. This is because the year has been converted to use the Arabic calendar. Some cultural differences, such as different currency or different month names, are obvious. Other cultural differences are surprising and subtle. For example, in some cultures, the grouping of numbers is done unevenly. In the "te-IN" culture (Telugu in India), groups have 3 digits and then 2 digits. The number 1000000 (one million) is written as "10,00,000". Some cultures do not group numbers at all. All of these subtle cultural differences are handled by the jQuery Globalization plugin automatically. Getting dates right can be especially tricky. Different cultures have different calendars such as the Gregorian and UmAlQura calendars. A single culture can even have multiple calendars. For example, the Japanese culture uses both the Gregorian calendar and a Japanese calendar that has eras named after Japanese emperors. The Globalization Plugin includes methods for converting dates between all of these different calendars. Using Language Tags The jQuery Globalization plugin uses the language tags defined in the RFC 4646 and RFC 5646 standards to identity cultures (see http://tools.ietf.org/html/rfc5646). A language tag is composed out of one or more subtags separated by hyphens. For example: Language Tag Language Name (in English) en-AU English (Australia) en-BZ English (Belize) en-CA English (Canada) Id Indonesian zh-CHS Chinese (Simplified) Legacy Zu isiZulu Notice that a single language, such as English, can have several language tags. Speakers of English in Canada format numbers, currencies, and dates using different conventions than speakers of English in Australia or the United States. You can find the language tag for a particular culture by using the Language Subtag Lookup tool located here:  http://rishida.net/utils/subtags/ The jQuery Globalization plugin download includes a folder named globinfo that contains the information for each of the 350 cultures. Actually, this folder contains more than 700 files because the folder includes both minified and un-minified versions of each file. For example, the globinfo folder includes JavaScript files named jQuery.glob.en-AU.js for English Australia, jQuery.glob.id.js for Indonesia, and jQuery.glob.zh-CHS for Chinese (Simplified) Legacy. Example: Setting a Particular Culture Imagine that you have been asked to create a German website and want to format all of the dates, currencies, and numbers using German formatting conventions correctly in JavaScript on the client. The HTML for the page might look like this: Notice the span tags above. They mark the areas of the page that we want to format with the Globalization plugin. We want to format the product price, the date the product is available, and the units of the product in stock. To use the jQuery Globalization plugin, we’ll add three JavaScript files to the page: the jQuery library, the jQuery Globalization plugin, and the culture information for a particular language: In this case, I’ve statically added the jQuery.glob.de-DE.js JavaScript file that contains the culture information for German. The language tag “de-DE” is used for German as spoken in Germany. Now that I have all of the necessary scripts, I can use the Globalization plugin to format the product price, date available, and units in stock values using the following client-side JavaScript: The jQuery Globalization plugin extends the jQuery library with new methods - including new methods named preferCulture() and format(). The preferCulture() method enables you to set the default culture used by the jQuery Globalization plugin methods. Notice that the preferCulture() method accepts a language tag. The method will find the closest culture that matches the language tag. The $.format() method is used to actually format the currencies, dates, and numbers. The second parameter passed to the $.format() method is a format specifier. For example, passing “c” causes the value to be formatted as a currency. The ReadMe file at github details the meaning of all of the various format specifiers: http://github.com/nje/jquery-glob When we open the page in a browser, everything is formatted correctly according to German language conventions. A euro symbol is used for the currency symbol. The date is formatted using German day and month names. Finally, a period instead of a comma is used a number separator: You can see a running example of the above approach with the 3_GermanSite.htm file in this samples download. Example: Enabling a User to Dynamically Select a Culture In the previous example we explicitly said that we wanted to globalize in German (by referencing the jQuery.glob.de-DE.js file). Let’s now look at the first of a few examples that demonstrate how to dynamically set the globalization culture to use. Imagine that you want to display a dropdown list of all of the 350 cultures in a page. When someone selects a culture from the dropdown list, you want all of the dates in the page to be formatted using the selected culture. Here’s the HTML for the page: Notice that all of the dates are contained in a <span> tag with a data-date attribute (data-* attributes are a new feature of HTML 5 that conveniently also still work with older browsers). We’ll format the date represented by the data-date attribute when a user selects a culture from the dropdown list. In order to display dates for any possible culture, we’ll include the jQuery.glob.all.js file like this: The jQuery Globalization plugin includes a JavaScript file named jQuery.glob.all.js. This file contains globalization information for all of the more than 350 cultures supported by the Globalization plugin.  At 367KB minified, this file is not small. Because of the size of this file, unless you really need to use all of these cultures at the same time, we recommend that you add the individual JavaScript files for particular cultures that you intend to support instead of the combined jQuery.glob.all.js to a page. In the next sample I’ll show how to dynamically load just the language files you need. Next, we’ll populate the dropdown list with all of the available cultures. We can use the $.cultures property to get all of the loaded cultures: Finally, we’ll write jQuery code that grabs every span element with a data-date attribute and format the date: The jQuery Globalization plugin’s parseDate() method is used to convert a string representation of a date into a JavaScript date. The plugin’s format() method is used to format the date. The “D” format specifier causes the date to be formatted using the long date format. And now the content will be globalized correctly regardless of which of the 350 languages a user visiting the page selects.  You can see a running example of the above approach with the 4_SelectCulture.htm file in this samples download. Example: Loading Globalization Files Dynamically As mentioned in the previous section, you should avoid adding the jQuery.glob.all.js file to a page whenever possible because the file is so large. A better alternative is to load the globalization information that you need dynamically. For example, imagine that you have created a dropdown list that displays a list of languages: The following jQuery code executes whenever a user selects a new language from the dropdown list. The code checks whether the globalization file associated with the selected language has already been loaded. If the globalization file has not been loaded then the globalization file is loaded dynamically by taking advantage of the jQuery $.getScript() method. The globalizePage() method is called after the requested globalization file has been loaded, and contains the client-side code to perform the globalization. The advantage of this approach is that it enables you to avoid loading the entire jQuery.glob.all.js file. Instead you only need to load the files that you need and you don’t need to load the files more than once. The 5_Dynamic.htm file in this samples download demonstrates how to implement this approach. Example: Setting the User Preferred Language Automatically Many websites detect a user’s preferred language from their browser settings and automatically use it when globalizing content. A user can set a preferred language for their browser. Then, whenever the user requests a page, this language preference is included in the request in the Accept-Language header. When using Microsoft Internet Explorer, you can set your preferred language by following these steps: Select the menu option Tools, Internet Options. Select the General tab. Click the Languages button in the Appearance section. Click the Add button to add a new language to the list of languages. Move your preferred language to the top of the list. Notice that you can list multiple languages in the Language Preference dialog. All of these languages are sent in the order that you listed them in the Accept-Language header: Accept-Language: fr-FR,id-ID;q=0.7,en-US;q=0.3 Strangely, you cannot retrieve the value of the Accept-Language header from client JavaScript. Microsoft Internet Explorer and Mozilla Firefox support a bevy of language related properties exposed by the window.navigator object, such as windows.navigator.browserLanguage and window.navigator.language, but these properties represent either the language set for the operating system or the language edition of the browser. These properties don’t enable you to retrieve the language that the user set as his or her preferred language. The only reliable way to get a user’s preferred language (the value of the Accept-Language header) is to write server code. For example, the following ASP.NET page takes advantage of the server Request.UserLanguages property to assign the user’s preferred language to a client JavaScript variable named acceptLanguage (which then allows you to access the value using client-side JavaScript): In order for this code to work, the culture information associated with the value of acceptLanguage must be included in the page. For example, if someone’s preferred culture is fr-FR (French in France) then you need to include either the jQuery.glob.fr-FR.js or the jQuery.glob.all.js JavaScript file in the page or the culture information won’t be available.  The “6_AcceptLanguages.aspx” sample in this samples download demonstrates how to implement this approach. If the culture information for the user’s preferred language is not included in the page then the $.preferCulture() method will fall back to using the neutral culture (for example, using jQuery.glob.fr.js instead of jQuery.glob.fr-FR.js). If the neutral culture information is not available then the $.preferCulture() method falls back to the default culture (English). Example: Using the Globalization Plugin with the jQuery UI DatePicker One of the goals of the Globalization plugin is to make it easier to build jQuery widgets that can be used with different cultures. We wanted to make sure that the jQuery Globalization plugin could work with existing jQuery UI plugins such as the DatePicker plugin. To that end, we created a patched version of the DatePicker plugin that can take advantage of the Globalization plugin when rendering a calendar. For example, the following figure illustrates what happens when you add the jQuery Globalization and the patched jQuery UI DatePicker plugin to a page and select Indonesian as the preferred culture: Notice that the headers for the days of the week are displayed using Indonesian day name abbreviations. Furthermore, the month names are displayed in Indonesian. You can download the patched version of the jQuery UI DatePicker from our github website. Or you can use the version included in this samples download and used by the 7_DatePicker.htm sample file. Summary I’m excited about our continuing participation in the jQuery community. This Globalization plugin is the third jQuery plugin that we’ve released. We’ve really appreciated all of the great feedback and design suggestions on the jQuery templating and data-linking prototypes that we released earlier this year.  We also want to thank the jQuery and jQuery UI teams for working with us to create these plugins. Hope this helps, Scott P.S. In addition to blogging, I am also now using Twitter for quick updates and to share links. You can follow me at: twitter.com/scottgu

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  • MySQL Syslog Audit Plugin

    - by jonathonc
    This post shows the construction process of the Syslog Audit plugin that was presented at MySQL Connect 2012. It is based on an environment that has the appropriate development tools enabled including gcc,g++ and cmake. It also assumes you have downloaded the MySQL source code (5.5.16 or higher) and have compiled and installed the system into the /usr/local/mysql directory ready for use.  The information provided below is designed to show the different components that make up a plugin, and specifically an audit type plugin, and how it comes together to be used within the MySQL service. The MySQL Reference Manual contains information regarding the plugin API and how it can be used, so please refer there for more detailed information. The code in this post is designed to give the simplest information necessary, so handling every return code, managing race conditions etc is not part of this example code. Let's start by looking at the most basic implementation of our plugin code as seen below: /*    Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved.    Author:  Jonathon Coombes    Licence: GPL    Description: An auditing plugin that logs to syslog and                 can adjust the loglevel via the system variables. */ #include <stdio.h> #include <string.h> #include <mysql/plugin_audit.h> #include <syslog.h> There is a commented header detailing copyright/licencing and meta-data information and then the include headers. The two important include statements for our plugin are the syslog.h plugin, which gives us the structures for syslog, and the plugin_audit.h include which has details regarding the audit specific plugin api. Note that we do not need to include the general plugin header plugin.h, as this is done within the plugin_audit.h file already. To implement our plugin within the current implementation we need to add it into our source code and compile. > cd /usr/local/src/mysql-5.5.28/plugin > mkdir audit_syslog > cd audit_syslog A simple CMakeLists.txt file is created to manage the plugin compilation: MYSQL_ADD_PLUGIN(audit_syslog audit_syslog.cc MODULE_ONLY) Run the cmake  command at the top level of the source and then you can compile the plugin using the 'make' command. This results in a compiled audit_syslog.so library, but currently it is not much use to MySQL as there is no level of api defined to communicate with the MySQL service. Now we need to define the general plugin structure that enables MySQL to recognise the library as a plugin and be able to install/uninstall it and have it show up in the system. The structure is defined in the plugin.h file in the MySQL source code.  /*   Plugin library descriptor */ mysql_declare_plugin(audit_syslog) {   MYSQL_AUDIT_PLUGIN,           /* plugin type                    */   &audit_syslog_descriptor,     /* descriptor handle               */   "audit_syslog",               /* plugin name                     */   "Author Name",                /* author                          */   "Simple Syslog Audit",        /* description                     */   PLUGIN_LICENSE_GPL,           /* licence                         */   audit_syslog_init,            /* init function     */   audit_syslog_deinit,          /* deinit function */   0x0001,                       /* plugin version                  */   NULL,                         /* status variables        */   NULL,                         /* system variables                */   NULL,                         /* no reserves                     */   0,                            /* no flags                        */ } mysql_declare_plugin_end; The general plugin descriptor above is standard for all plugin types in MySQL. The plugin type is defined along with the init/deinit functions and interface methods into the system for sharing information, and various other metadata information. The descriptors have an internally recognised version number so that plugins can be matched against the api on the running server. The other details are usually related to the type-specific methods and structures to implement the plugin. Each plugin has a type-specific descriptor as well which details how the plugin is implemented for the specific purpose of that plugin type. /*   Plugin type-specific descriptor */ static struct st_mysql_audit audit_syslog_descriptor= {   MYSQL_AUDIT_INTERFACE_VERSION,                        /* interface version    */   NULL,                                                 /* release_thd function */   audit_syslog_notify,                                  /* notify function      */   { (unsigned long) MYSQL_AUDIT_GENERAL_CLASSMASK |                     MYSQL_AUDIT_CONNECTION_CLASSMASK }  /* class mask           */ }; In this particular case, the release_thd function has not been defined as it is not required. The important method for auditing is the notify function which is activated when an event occurs on the system. The notify function is designed to activate on an event and the implementation will determine how it is handled. For the audit_syslog plugin, the use of the syslog feature sends all events to the syslog for recording. The class mask allows us to determine what type of events are being seen by the notify function. There are currently two major types of event: 1. General Events: This includes general logging, errors, status and result type events. This is the main one for tracking the queries and operations on the database. 2. Connection Events: This group is based around user logins. It monitors connections and disconnections, but also if somebody changes user while connected. With most audit plugins, the principle behind the plugin is to track changes to the system over time and counters can be an important part of this process. The next step is to define and initialise the counters that are used to track the events in the service. There are 3 counters defined in total for our plugin - the # of general events, the # of connection events and the total number of events.  static volatile int total_number_of_calls; /* Count MYSQL_AUDIT_GENERAL_CLASS event instances */ static volatile int number_of_calls_general; /* Count MYSQL_AUDIT_CONNECTION_CLASS event instances */ static volatile int number_of_calls_connection; The init and deinit functions for the plugin are there to be called when the plugin is activated and when it is terminated. These offer the best option to initialise the counters for our plugin: /*  Initialize the plugin at server start or plugin installation. */ static int audit_syslog_init(void *arg __attribute__((unused))) {     openlog("mysql_audit:",LOG_PID|LOG_PERROR|LOG_CONS,LOG_USER);     total_number_of_calls= 0;     number_of_calls_general= 0;     number_of_calls_connection= 0;     return(0); } The init function does a call to openlog to initialise the syslog functionality. The parameters are the service to log under ("mysql_audit" in this case), the syslog flags and the facility for the logging. Then each of the counters are initialised to zero and a success is returned. If the init function is not defined, it will return success by default. /*  Terminate the plugin at server shutdown or plugin deinstallation. */ static int audit_syslog_deinit(void *arg __attribute__((unused))) {     closelog();     return(0); } The deinit function will simply close our syslog connection and return success. Note that the syslog functionality is part of the glibc libraries and does not require any external factors.  The function names are what we define in the general plugin structure, so these have to match otherwise there will be errors. The next step is to implement the event notifier function that was defined in the type specific descriptor (audit_syslog_descriptor) which is audit_syslog_notify. /* Event notifier function */ static void audit_syslog_notify(MYSQL_THD thd __attribute__((unused)), unsigned int event_class, const void *event) { total_number_of_calls++; if (event_class == MYSQL_AUDIT_GENERAL_CLASS) { const struct mysql_event_general *event_general= (const struct mysql_event_general *) event; number_of_calls_general++; syslog(audit_loglevel,"%lu: User: %s Command: %s Query: %s\n", event_general->general_thread_id, event_general->general_user, event_general->general_command, event_general->general_query ); } else if (event_class == MYSQL_AUDIT_CONNECTION_CLASS) { const struct mysql_event_connection *event_connection= (const struct mysql_event_connection *) event; number_of_calls_connection++; syslog(audit_loglevel,"%lu: User: %s@%s[%s] Event: %d Status: %d\n", event_connection->thread_id, event_connection->user, event_connection->host, event_connection->ip, event_connection->event_subclass, event_connection->status ); } }   In the case of an event, the notifier function is called. The first step is to increment the total number of events that have occurred in our database.The event argument is then cast into the appropriate event structure depending on the class type, of general event or connection event. The event type counters are incremented and details are sent via the syslog() function out to the system log. There are going to be different line formats and information returned since the general events have different data compared to the connection events, even though some of the details overlap, for example, user, thread id, host etc. On compiling the code now, there should be no errors and the resulting audit_syslog.so can be loaded into the server and ready to use. Log into the server and type: mysql> INSTALL PLUGIN audit_syslog SONAME 'audit_syslog.so'; This will install the plugin and will start updating the syslog immediately. Note that the audit plugin attaches to the immediate thread and cannot be uninstalled while that thread is active. This means that you cannot run the UNISTALL command until you log into a different connection (thread) on the server. Once the plugin is loaded, the system log will show output such as the following: Oct  8 15:33:21 machine mysql_audit:[8337]: 87: User: root[root] @ localhost []  Command: (null)  Query: INSTALL PLUGIN audit_syslog SONAME 'audit_syslog.so' Oct  8 15:33:21 machine mysql_audit:[8337]: 87: User: root[root] @ localhost []  Command: Query  Query: INSTALL PLUGIN audit_syslog SONAME 'audit_syslog.so' Oct  8 15:33:40 machine mysql_audit:[8337]: 87: User: root[root] @ localhost []  Command: (null)  Query: show tables Oct  8 15:33:40 machine mysql_audit:[8337]: 87: User: root[root] @ localhost []  Command: Query  Query: show tables Oct  8 15:33:43 machine mysql_audit:[8337]: 87: User: root[root] @ localhost []  Command: (null)  Query: select * from t1 Oct  8 15:33:43 machine mysql_audit:[8337]: 87: User: root[root] @ localhost []  Command: Query  Query: select * from t1 It appears that two of each event is being shown, but in actuality, these are two separate event types - the result event and the status event. This could be refined further by changing the audit_syslog_notify function to handle the different event sub-types in a different manner.  So far, it seems that the logging is working with events showing up in the syslog output. The issue now is that the counters created earlier to track the number of events by type are not accessible when the plugin is being run. Instead there needs to be a way to expose the plugin specific information to the service and vice versa. This could be done via the information_schema plugin api, but for something as simple as counters, the obvious choice is the system status variables. This is done using the standard structure and the declaration: /*  Plugin status variables for SHOW STATUS */ static struct st_mysql_show_var audit_syslog_status[]= {   { "Audit_syslog_total_calls",     (char *) &total_number_of_calls,     SHOW_INT },   { "Audit_syslog_general_events",     (char *) &number_of_calls_general,     SHOW_INT },   { "Audit_syslog_connection_events",     (char *) &number_of_calls_connection,     SHOW_INT },   { 0, 0, SHOW_INT } };   The structure is simply the name that will be displaying in the mysql service, the address of the associated variables, and the data type being used for the counter. It is finished with a blank structure to show that there are no more variables. Remember that status variables may have the same name for variables from other plugin, so it is considered appropriate to add the plugin name at the start of the status variable name to avoid confusion. Looking at the status variables in the mysql client shows something like the following: mysql> show global status like "audit%"; +--------------------------------+-------+ | Variable_name                  | Value | +--------------------------------+-------+ | Audit_syslog_connection_events | 1     | | Audit_syslog_general_events    | 2     | | Audit_syslog_total_calls       | 3     | +--------------------------------+-------+ 3 rows in set (0.00 sec) The final connectivity piece for the plugin is to allow the interactive change of the logging level between the plugin and the system. This requires the ability to send changes via the mysql service through to the plugin. This is done using the system variables interface and defining a single variable to keep track of the active logging level for the facility. /* Plugin system variables for SHOW VARIABLES */ static MYSQL_SYSVAR_STR(loglevel, audit_loglevel,                         PLUGIN_VAR_RQCMDARG,                         "User can specify the log level for auditing",                         audit_loglevel_check, audit_loglevel_update, "LOG_NOTICE"); static struct st_mysql_sys_var* audit_syslog_sysvars[] = {     MYSQL_SYSVAR(loglevel),     NULL }; So now the system variable 'loglevel' is defined for the plugin and associated to the global variable 'audit_loglevel'. The check or validation function is defined to make sure that no garbage values are attempted in the update of the variable. The update function is used to save the new value to the variable. Note that the audit_syslog_sysvars structure is defined in the general plugin descriptor to associate the link between the plugin and the system and how much they interact. Next comes the implementation of the validation function and the update function for the system variable. It is worth noting that if you have a simple numeric such as integers for the variable types, the validate function is often not required as MySQL will handle the automatic check and validation of simple types. /* longest valid value */ #define MAX_LOGLEVEL_SIZE 100 /* hold the valid values */ static const char *possible_modes[]= { "LOG_ERROR", "LOG_WARNING", "LOG_NOTICE", NULL };  static int audit_loglevel_check(     THD*                        thd,    /*!< in: thread handle */     struct st_mysql_sys_var*    var,    /*!< in: pointer to system                                         variable */     void*                       save,   /*!< out: immediate result                                         for update function */     struct st_mysql_value*      value)  /*!< in: incoming string */ {     char buff[MAX_LOGLEVEL_SIZE];     const char *str;     const char **found;     int length;     length= sizeof(buff);     if (!(str= value->val_str(value, buff, &length)))         return 1;     /*         We need to return a pointer to a locally allocated value in "save".         Here we pick to search for the supplied value in an global array of         constant strings and return a pointer to one of them.         The other possiblity is to use the thd_alloc() function to allocate         a thread local buffer instead of the global constants.     */     for (found= possible_modes; *found; found++)     {         if (!strcmp(*found, str))         {             *(const char**)save= *found;             return 0;         }     }     return 1; } The validation function is simply to take the value being passed in via the SET GLOBAL VARIABLE command and check if it is one of the pre-defined values allowed  in our possible_values array. If it is found to be valid, then the value is assigned to the save variable ready for passing through to the update function. static void audit_loglevel_update(     THD*                        thd,        /*!< in: thread handle */     struct st_mysql_sys_var*    var,        /*!< in: system variable                                             being altered */     void*                       var_ptr,    /*!< out: pointer to                                             dynamic variable */     const void*                 save)       /*!< in: pointer to                                             temporary storage */ {     /* assign the new value so that the server can read it */     *(char **) var_ptr= *(char **) save;     /* assign the new value to the internal variable */     audit_loglevel= *(char **) save; } Since all the validation has been done already, the update function is quite simple for this plugin. The first part is to update the system variable pointer so that the server can read the value. The second part is to update our own global plugin variable for tracking the value. Notice that the save variable is passed in as a void type to allow handling of various data types, so it must be cast to the appropriate data type when assigning it to the variables. Looking at how the latest changes affect the usage of the plugin and the interaction within the server shows: mysql> show global variables like "audit%"; +-----------------------+------------+ | Variable_name         | Value      | +-----------------------+------------+ | audit_syslog_loglevel | LOG_NOTICE | +-----------------------+------------+ 1 row in set (0.00 sec) mysql> set global audit_syslog_loglevel="LOG_ERROR"; Query OK, 0 rows affected (0.00 sec) mysql> show global status like "audit%"; +--------------------------------+-------+ | Variable_name                  | Value | +--------------------------------+-------+ | Audit_syslog_connection_events | 1     | | Audit_syslog_general_events    | 11    | | Audit_syslog_total_calls       | 12    | +--------------------------------+-------+ 3 rows in set (0.00 sec) mysql> show global variables like "audit%"; +-----------------------+-----------+ | Variable_name         | Value     | +-----------------------+-----------+ | audit_syslog_loglevel | LOG_ERROR | +-----------------------+-----------+ 1 row in set (0.00 sec)   So now we have a plugin that will audit the events on the system and log the details to the system log. It allows for interaction to see the number of different events within the server details and provides a mechanism to change the logging level interactively via the standard system methods of the SET command. A more complex auditing plugin may have more detailed code, but each of the above areas is what will be involved and simply expanded on to add more functionality. With the above skeleton code, it is now possible to create your own audit plugins to implement your own auditing requirements. If, however, you are not of the coding persuasion, then you could always consider the option of the MySQL Enterprise Audit plugin that is available to purchase.

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  • Ops Center 12c - Provisioning Solaris Using a Card-Based NIC

    - by scottdickson
    It's been a long time since last I added something here, but having some conversations this last week, I got inspired to update things. I've been spending a lot of time with Ops Center for managing and installing systems these days.  So, I suspect a number of my upcoming posts will be in that area. Today, I want to look at how to provision Solaris using Ops Center when your network is not connected to one of the built-in NICs.  We'll talk about how this can work for both Solaris 10 and Solaris 11, since they are pretty similar.  In both cases, WANboot is a key piece of the story. Here's what I want to do:  I have a Sun Fire T2000 server with a Quad-GbE nxge card installed.  The only network is connected to port 2 on that card rather than the built-in network interfaces.  I want to install Solaris on it across the network, either Solaris 10 or Solaris 11.  I have met with a lot of customers lately who have a similar architecture.  Usually, they have T4-4 servers with the network connected via 10GbE connections. Add to this mix the fact that I use Ops Center to manage the systems in my lab, so I really would like to add this to Ops Center.  If possible, I would like this to be completely hands free.  I can't quite do that yet. Close, but not quite. WANBoot or Old-Style NetBoot? When a system is installed from the network, it needs some help getting the process rolling.  It has to figure out what its network configuration (IP address, gateway, etc.) ought to be.  It needs to figure out what server is going to help it boot and install, and it needs the instructions for the installation.  There are two different ways to bootstrap an installation of Solaris on SPARC across the network.   The old way uses a broadcast of RARP or more recently DHCP to obtain the IP configuration and the rest of the information needed.  The second is to explicitly configure this information in the OBP and use WANBoot for installation WANBoot has a number of benefits over broadcast-based installation: it is not restricted to a single subnet; it does not require special DHCP configuration or DHCP helpers; it uses standard HTTP and HTTPS protocols which traverse firewalls much more easily than NFS-based package installation.  But, WANBoot is not available on really old hardware and WANBoot requires the use o Flash Archives in Solaris 10.  Still, for many people, this is a great approach. As it turns out, WANBoot is necessary if you plan to install using a NIC on a card rather than a built-in NIC. Identifying Which Network Interface to Use One of the trickiest aspects to this process, and the one that actually requires manual intervention to set up, is identifying how the OBP and Solaris refer to the NIC that we want to use to boot.  The OBP already has device aliases configured for the built-in NICs called net, net0, net1, net2, net3.  The device alias net typically points to net0 so that when you issue the command  "boot net -v install", it uses net0 for the boot.  Our task is to figure out the network instance for the NIC we want to use.  We will need to get to the OBP console of the system we want to install in order to figure out what the network should be called.  I will presume you know how to get to the ok prompt.  Once there, we have to see what networks the OBP sees and identify which one is associated with our NIC using the OBP command show-nets. SunOS Release 5.11 Version 11.0 64-bit Copyright (c) 1983, 2011, Oracle and/or its affiliates. All rights reserved. {4} ok banner Sun Fire T200, No Keyboard Copyright (c) 1998, 2010, Oracle and/or its affiliates. All rights reserved. OpenBoot 4.30.4.b, 32640 MB memory available, Serial #69057548. Ethernet address 0:14:4f:1d:bc:c, Host ID: 841dbc0c. {4} ok show-nets a) /pci@7c0/pci@0/pci@2/network@0,1 b) /pci@7c0/pci@0/pci@2/network@0 c) /pci@780/pci@0/pci@8/network@0,3 d) /pci@780/pci@0/pci@8/network@0,2 e) /pci@780/pci@0/pci@8/network@0,1 f) /pci@780/pci@0/pci@8/network@0 g) /pci@780/pci@0/pci@1/network@0,1 h) /pci@780/pci@0/pci@1/network@0 q) NO SELECTION Enter Selection, q to quit: d /pci@780/pci@0/pci@8/network@0,2 has been selected. Type ^Y ( Control-Y ) to insert it in the command line. e.g. ok nvalias mydev ^Y for creating devalias mydev for /pci@780/pci@0/pci@8/network@0,2 {4} ok devalias ... net3 /pci@7c0/pci@0/pci@2/network@0,1 net2 /pci@7c0/pci@0/pci@2/network@0 net1 /pci@780/pci@0/pci@1/network@0,1 net0 /pci@780/pci@0/pci@1/network@0 net /pci@780/pci@0/pci@1/network@0 ... name aliases By looking at the devalias and the show-nets output, we can see that our Quad-GbE card must be the device nodes starting with  /pci@780/pci@0/pci@8/network@0.  The cable for our network is plugged into the 3rd slot, so the device address for our network must be /pci@780/pci@0/pci@8/network@0,2. With that, we can create a device alias for our network interface.  Naming the device alias may take a little bit of trial and error, especially in Solaris 11 where the device alias seems to matter more with the new virtualized network stack. So far in my testing, since this is the "next" network interface to be used, I have found success in naming it net4, even though it's a NIC in the middle of a card that might, by rights, be called net6 (assuming the 0th interface on the card is the next interface identified by Solaris and this is the 3rd interface on the card).  So, we will call it net4.  We need to assign a device alias to it: {4} ok nvalias net4 /pci@780/pci@0/pci@8/network@0,2 {4} ok devalias net4 /pci@780/pci@0/pci@8/network@0,2 ... We also may need to have the MAC for this particular interface, so let's get it, too.  To do this, we go to the device and interrogate its properties. {4} ok cd /pci@780/pci@0/pci@8/network@0,2 {4} ok .properties assigned-addresses 82060210 00000000 03000000 00000000 01000000 82060218 00000000 00320000 00000000 00008000 82060220 00000000 00328000 00000000 00008000 82060230 00000000 00600000 00000000 00100000 local-mac-address 00 21 28 20 42 92 phy-type mif ... From this, we can see that the MAC for this interface is  00:21:28:20:42:92.  We will need this later. This is all we need to do at the OBP.  Now, we can configure Ops Center to use this interface. Network Boot in Solaris 10 Solaris 10 turns out to be a little simpler than Solaris 11 for this sort of a network boot.  Since WANBoot in Solaris 10 fetches a specified In order to install the system using Ops Center, it is necessary to create a OS Provisioning profile and its corresponding plan.  I am going to presume that you already know how to do this within Ops Center 12c and I will just cover the differences between a regular profile and a profile that can use an alternate interface. Create a OS Provisioning profile for Solaris 10 as usual.  However, when you specify the network resources for the primary network, click on the name of the NIC, probably GB_0, and rename it to GB_N/netN, where N is the instance number you used previously in creating the device alias.  This is where the trial and error may come into play.  You may need to try a few instance numbers before you, the OBP, and Solaris all agree on the instance number.  Mark this as the boot network. For Solaris 10, you ought to be able to then apply the OS Provisioning profile to the server and it should install using that interface.  And if you put your cards in the same slots and plug the networks into the same NICs, this profile is reusable across multiple servers. Why This Works If you watch the console as Solaris boots during the OSP process, Ops Center is going to look for the device alias netN.  Since WANBoot requires a device alias called just net, Ops Center uses the value of your netN device alias and assigns that device to the net alias.  That means that boot net will automatically use this device.  Very cool!  Here's a trace from the console as Ops Center provisions a server: Sun Sun Fire T200, No KeyboardCopyright (c) 1998, 2010, Oracle and/or its affiliates. All rights reserved.OpenBoot 4.30.4.b, 32640 MB memory available, Serial #69057548.Ethernet address 0:14:4f:1d:bc:c, Host ID: 841dbc0c.auto-boot? =            false{0} ok  {0} ok printenv network-boot-argumentsnetwork-boot-arguments =  host-ip=10.140.204.234,router-ip=10.140.204.1,subnet-mask=255.255.254.0,hostname=atl-sewr-52,client-id=0100144F1DBC0C,file=http://10.140.204.22:5555/cgi-bin/wanboot-cgi{0} ok {0} ok devalias net net                      /pci@780/pci@0/pci@1/network@0{0} ok devalias net4 net4                     /pci@780/pci@0/pci@8/network@0,2{0} ok devalias net /pci@780/pci@0/pci@8/network@0,2{0} ok setenv network-boot-arguments host-ip=10.140.204.234,router-ip=10.140.204.1,subnet-mask=255.255.254.0,hostname=atl-sewr-52,client-id=0100144F1DBC0C,file=http://10.140.204.22:8004/cgi-bin/wanboot-cginetwork-boot-arguments =  host-ip=10.140.204.234,router-ip=10.140.204.1,subnet-mask=255.255.254.0,hostname=atl-sewr-52,client-id=0100144F1DBC0C,file=http://10.140.204.22:8004/cgi-bin/wanboot-cgi{0} ok {0} ok boot net - installBoot device: /pci@780/pci@0/pci@8/network@0,2  File and args: - install/pci@780/pci@0/pci@8/network@0,2: 1000 Mbps link up<time unavailable> wanboot info: WAN boot messages->console<time unavailable> wanboot info: configuring /pci@780/pci@0/pci@8/network@0,2 See what happened?  Ops Center looked for the network device alias called net4 that we specified in the profile, took the value from it, and made it the net device alias for the boot.  Pretty cool! WANBoot and Solaris 11 Solaris 11 requires an additional step since the Automated Installer in Solaris 11 uses the MAC address of the network to figure out which manifest to use for system installation.  In order to make sure this is available, we have to take an extra step to associate the MAC of the NIC on the card with the host.  So, in addition to creating the device alias like we did above, we also have to declare to Ops Center that the host has this new MAC. Declaring the NIC Start out by discovering the hardware as usual.  Once you have discovered it, take a look under the Connectivity tab to see what networks it has discovered.  In the case of this system, it shows the 4 built-in networks, but not the networks on the additional cards.  These are not directly visible to the system controller.  In order to add the additional network interface to the hardware asset, it is necessary to Declare it.  We will declare that we have a server with this additional NIC, but we will also  specify the existing GB_0 network so that Ops Center can associate the right resources together.  The GB_0 acts as sort of a key to tie our new declaration to the old system already discovered.  Go to the Assets tab, select All Assets, and then in the Actions tab, select Add Asset.  Rather than going through a discovery this time, we will manually declare a new asset. When we declare it, we will give the hostname, IP address, system model that match those that have already been discovered.  Then, we will declare both GB_0 with its existing MAC and the new GB_4 with its MAC.  Remember that we collected the MAC for GB_4 when we created its device alias. After you declare the asset, you will see the new NIC in the connectivity tab for the asset.  You will notice that only the NICs you listed when you declared it are seen now.  If you want Ops Center to see all of the existing NICs as well as the additional one, declare them as well.  Add the other GB_1, GB_2, GB_3 links and their MACs just as you did GB_0 and GB_4.  Installing the OS  Once you have declared the asset, you can create an OS Provisioning profile for Solaris 11 in the same way that you did for Solaris 10.  The only difference from any other provisioning profile you might have created already is the network to use for installation.  Again, use GB_N/netN where N is the interface number you used for your device alias and in your declaration.  And away you go.  When the system boots from the network, the automated installer (AI) is able to see which system manifest to use, based on the new MAC that was associated, and the system gets installed. {0} ok {0} ok printenv network-boot-argumentsnetwork-boot-arguments =  host-ip=10.140.204.234,router-ip=10.140.204.1,subnet-mask=255.255.254.0,hostname=atl-sewr-52,client-id=01002128204292,file=http://10.140.204.22:5555/cgi-bin/wanboot-cgi{0} ok {0} ok devalias net net                      /pci@780/pci@0/pci@1/network@0{0} ok devalias net4 net4                     /pci@780/pci@0/pci@8/network@0,2{0} ok devalias net /pci@780/pci@0/pci@8/network@0,2{0} ok setenv network-boot-arguments host-ip=10.140.204.234,router-ip=10.140.204.1,subnet-mask=255.255.254.0,hostname=atl-sewr-52,client-id=01002128204292,file=http://10.140.204.22:5555/cgi-bin/wanboot-cginetwork-boot-arguments =  host-ip=10.140.204.234,router-ip=10.140.204.1,subnet-mask=255.255.254.0,hostname=atl-sewr-52,client-id=01002128204292,file=http://10.140.204.22:5555/cgi-bin/wanboot-cgi{0} ok {0} ok boot net - installBoot device: /pci@780/pci@0/pci@8/network@0,2  File and args: - install/pci@780/pci@0/pci@8/network@0,2: 1000 Mbps link up<time unavailable> wanboot info: WAN boot messages->console<time unavailable> wanboot info: configuring /pci@780/pci@0/pci@8/network@0,2...SunOS Release 5.11 Version 11.0 64-bitCopyright (c) 1983, 2011, Oracle and/or its affiliates. All rights reserved.Remounting root read/writeProbing for device nodes ...Preparing network image for useDownloading solaris.zlib--2012-02-17 15:10:17--  http://10.140.204.22:5555/var/js/AI/sparc//solaris.zlibConnecting to 10.140.204.22:5555... connected.HTTP request sent, awaiting response... 200 OKLength: 126752256 (121M) [text/plain]Saving to: `/tmp/solaris.zlib'100%[======================================>] 126,752,256 28.6M/s   in 4.4s    2012-02-17 15:10:21 (27.3 MB/s) - `/tmp/solaris.zlib' saved [126752256/126752256] Conclusion So, why go to all of this trouble?  More and more, I find that customers are wiring their data center to only use higher speed networks - 10GbE only to the hosts.  Some customers are moving aggressively toward consolidated networks combining storage and network on CNA NICs.  All of this means that network-based provisioning cannot rely exclusively on the built-in network interfaces.  So, it's important to be able to provision a system using other than the built-in networks.  Turns out, that this is pretty straight-forward for both Solaris 10 and Solaris 11 and fits into the Ops Center deployment process quite nicely. Hopefully, you will be able to use this as you build out your own private cloud solutions with Ops Center.

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  • Windows Azure Evolution &ndash; Caching (Preview)

    - by Shaun
    Caching is a popular topic when we are building a high performance and high scalable system not only on top of the cloud platform but the on-premise environment as well. On March 2011 the Windows Azure AppFabric Caching had been production launched. It provides an in-memory, distributed caching service over the cloud. And now, in this June 2012 update, the cache team announce a grand new caching solution on Windows Azure, which is called Windows Azure Caching (Preview). And the original Windows Azure AppFabric Caching was renamed to Windows Azure Shared Caching.   What’s Caching (Preview) If you had been using the Shared Caching you should know that it is constructed by a bunch of cache servers. And when you want to use you should firstly create a cache account from the developer portal and specify the size you want to use, which means how much memory you can use to store your data that wanted to be cached. Then you can add, get and remove them through your code through the cache URL. The Shared Caching is a multi-tenancy system which host all cached items across all users. So you don’t know which server your data was located. This caching mode works well and can take most of the cases. But it has some problems. The first one is the performance. Since the Shared Caching is a multi-tenancy system, which means all cache operations should go through the Shared Caching gateway and then routed to the server which have the data your are looking for. Even though there are some caches in the Shared Caching system it also takes time from your cloud services to the cache service. Secondary, the Shared Caching service works as a block box to the developer. The only thing we know is my cache endpoint, and that’s all. Someone may satisfied since they don’t want to care about anything underlying. But if you need to know more and want more control that’s impossible in the Shared Caching. The last problem would be the price and cost-efficiency. You pay the bill based on how much cache you requested per month. But when we host a web role or worker role, it seldom consumes all of the memory and CPU in the virtual machine (service instance). If using Shared Caching we have to pay for the cache service while waste of some of our memory and CPU locally. Since the issues above Microsoft offered a new caching mode over to us, which is the Caching (Preview). Instead of having a separated cache service, the Caching (Preview) leverage the memory and CPU in our cloud services (web role and worker role) as the cache clusters. Hence the Caching (Preview) runs on the virtual machines which hosted or near our cloud applications. Without any gateway and routing, since it located in the same data center and same racks, it provides really high performance than the Shared Caching. The Caching (Preview) works side-by-side to our application, initialized and worked as a Windows Service running in the virtual machines invoked by the startup tasks from our roles, we could get more information and control to them. And since the Caching (Preview) utilizes the memory and CPU from our existing cloud services, so it’s free. What we need to pay is the original computing price. And the resource on each machines could be used more efficiently.   Enable Caching (Preview) It’s very simple to enable the Caching (Preview) in a cloud service. Let’s create a new windows azure cloud project from Visual Studio and added an ASP.NET Web Role. Then open the role setting and select the Caching page. This is where we enable and configure the Caching (Preview) on a role. To enable the Caching (Preview) just open the “Enable Caching (Preview Release)” check box. And then we need to specify which mode of the caching clusters we want to use. There are two kinds of caching mode, co-located and dedicate. The co-located mode means we use the memory in the instances we run our cloud services (web role or worker role). By using this mode we must specify how many percentage of the memory will be used as the cache. The default value is 30%. So make sure it will not affect the role business execution. The dedicate mode will use all memory in the virtual machine as the cache. In fact it will reserve some for operation system, azure hosting etc.. But it will try to use as much as the available memory to be the cache. As you can see, the Caching (Preview) was defined based on roles, which means all instances of this role will apply the same setting and play as a whole cache pool, and you can consume it by specifying the name of the role, which I will demonstrate later. And in a windows azure project we can have more than one role have the Caching (Preview) enabled. Then we will have more caches. For example, let’s say I have a web role and worker role. The web role I specified 30% co-located caching and the worker role I specified dedicated caching. If I have 3 instances of my web role and 2 instances of my worker role, then I will have two caches. As the figure above, cache 1 was contributed by three web role instances while cache 2 was contributed by 2 worker role instances. Then we can add items into cache 1 and retrieve it from web role code and worker role code. But the items stored in cache 1 cannot be retrieved from cache 2 since they are isolated. Back to our Visual Studio we specify 30% of co-located cache and use the local storage emulator to store the cache cluster runtime status. Then at the bottom we can specify the named caches. Now we just use the default one. Now we had enabled the Caching (Preview) in our web role settings. Next, let’s have a look on how to consume our cache.   Consume Caching (Preview) The Caching (Preview) can only be consumed by the roles in the same cloud services. As I mentioned earlier, a cache contributed by web role can be connected from a worker role if they are in the same cloud service. But you cannot consume a Caching (Preview) from other cloud services. This is different from the Shared Caching. The Shared Caching is opened to all services if it has the connection URL and authentication token. To consume the Caching (Preview) we need to add some references into our project as well as some configuration in the Web.config. NuGet makes our life easy. Right click on our web role project and select “Manage NuGet packages”, and then search the package named “WindowsAzure.Caching”. In the package list install the “Windows Azure Caching Preview”. It will download all necessary references from the NuGet repository and update our Web.config as well. Open the Web.config of our web role and find the “dataCacheClients” node. Under this node we can specify the cache clients we are going to use. For each cache client it will use the role name to identity and find the cache. Since we only have this web role with the Caching (Preview) enabled so I pasted the current role name in the configuration. Then, in the default page I will add some code to show how to use the cache. I will have a textbox on the page where user can input his or her name, then press a button to generate the email address for him/her. And in backend code I will check if this name had been added in cache. If yes I will return the email back immediately. Otherwise, I will sleep the tread for 2 seconds to simulate the latency, then add it into cache and return back to the page. 1: protected void btnGenerate_Click(object sender, EventArgs e) 2: { 3: // check if name is specified 4: var name = txtName.Text; 5: if (string.IsNullOrWhiteSpace(name)) 6: { 7: lblResult.Text = "Error. Please specify name."; 8: return; 9: } 10:  11: bool cached; 12: var sw = new Stopwatch(); 13: sw.Start(); 14:  15: // create the cache factory and cache 16: var factory = new DataCacheFactory(); 17: var cache = factory.GetDefaultCache(); 18:  19: // check if the name specified is in cache 20: var email = cache.Get(name) as string; 21: if (email != null) 22: { 23: cached = true; 24: sw.Stop(); 25: } 26: else 27: { 28: cached = false; 29: // simulate the letancy 30: Thread.Sleep(2000); 31: email = string.Format("{0}@igt.com", name); 32: // add to cache 33: cache.Add(name, email); 34: } 35:  36: sw.Stop(); 37: lblResult.Text = string.Format( 38: "Cached = {0}. Duration: {1}s. {2} => {3}", 39: cached, sw.Elapsed.TotalSeconds.ToString("0.00"), name, email); 40: } The Caching (Preview) can be used on the local emulator so we just F5. The first time I entered my name it will take about 2 seconds to get the email back to me since it was not in the cache. But if we re-enter my name it will be back at once from the cache. Since the Caching (Preview) is distributed across all instances of the role, so we can scaling-out it by scaling-out our web role. Just use 2 instances and tweak some code to show the current instance ID in the page, and have another try. Then we can see the cache can be retrieved even though it was added by another instance.   Consume Caching (Preview) Across Roles As I mentioned, the Caching (Preview) can be consumed by all other roles within the same cloud service. For example, let’s add another web role in our cloud solution and add the same code in its default page. In the Web.config we add the cache client to one enabled in the last role, by specifying its role name here. Then we start the solution locally and go to web role 1, specify the name and let it generate the email to us. Since there’s no cache for this name so it will take about 2 seconds but will save the email into cache. And then we go to web role 2 and specify the same name. Then you can see it retrieve the email saved by the web role 1 and returned back very quickly. Finally then we can upload our application to Windows Azure and test again. Make sure you had changed the cache cluster status storage account to the real azure account.   More Awesome Features As a in-memory distributed caching solution, the Caching (Preview) has some fancy features I would like to highlight here. The first one is the high availability support. This is the first time I have heard that a distributed cache support high availability. In the distributed cache world if a cache cluster was failed, the data it stored will be lost. This behavior was introduced by Memcached and is followed by almost all distributed cache productions. But Caching (Preview) provides high availability, which means you can specify if the named cache will be backup automatically. If yes then the data belongs to this named cache will be replicated on another role instance of this role. Then if one of the instance was failed the data can be retrieved from its backup instance. To enable the backup just open the Caching page in Visual Studio. In the named cache you want to enable backup, change the Backup Copies value from 0 to 1. The value of Backup Copies only for 0 and 1. “0” means no backup and no high availability while “1” means enabled high availability with backup the data into another instance. But by using the high availability feature there are something we need to make sure. Firstly the high availability does NOT means the data in cache will never be lost for any kind of failure. For example, if we have a role with cache enabled that has 10 instances, and 9 of them was failed, then most of the cached data will be lost since the primary and backup instance may failed together. But normally is will not be happened since MS guarantees that it will use the instance in the different fault domain for backup cache. Another one is that, enabling the backup means you store two copies of your data. For example if you think 100MB memory is OK for cache, but you need at least 200MB if you enabled backup. Besides the high availability, the Caching (Preview) support more features introduced in Windows Server AppFabric Caching than the Windows Azure Shared Caching. It supports local cache with notification. It also support absolute and slide window expiration types as well. And the Caching (Preview) also support the Memcached protocol as well. This means if you have an application based on Memcached, you can use Caching (Preview) without any code changes. What you need to do is to change the configuration of how you connect to the cache. Similar as the Windows Azure Shared Caching, MS also offers the out-of-box ASP.NET session provider and output cache provide on top of the Caching (Preview).   Summary Caching is very important component when we building a cloud-based application. In the June 2012 update MS provides a new cache solution named Caching (Preview). Different from the existing Windows Azure Shared Caching, Caching (Preview) runs the cache cluster within the role instances we have deployed to the cloud. It gives more control, more performance and more cost-effect. So now we have two caching solutions in Windows Azure, the Shared Caching and Caching (Preview). If you need a central cache service which can be used by many cloud services and web sites, then you have to use the Shared Caching. But if you only need a fast, near distributed cache, then you’d better use Caching (Preview).   Hope this helps, Shaun All documents and related graphics, codes are provided "AS IS" without warranty of any kind. Copyright © Shaun Ziyan Xu. This work is licensed under the Creative Commons License.

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  • “I could use a little help here” or “I can do it myself, thank you” for Cloud Projects

    - by BuckWoody
    Windows Azure allows you to write code in languages within the .NET stack, you can use Java, C++, PHP, NodeJS and others. Code is code - other than keeping things stateless, using a Web or Worker Role in Azure is not all that different from working with an on-premises system. However…. Working in a scalable, component-based stateless architecture that can use federated security is not all that common for many developers. Some are used to owning the server, scaling up, and state-full paradigms that have a single security domain. Making the transition whilst trying to create a new software application or even port a previous one can be daunting. Sure, we have absolutely tons of free training, kits, videos, online books and more to learn on your own, but some things like architecture can be pivotal as you move along. So the question is, should you just strike out on your own for a Cloud project, or get Microsoft Consulting Services or another partner to work with you on your first one? I use a few decision points to help guide the projects I assist in. Note: I’m a huge fan of having help that ends up giving you training and leaves you in charge. If you do engage with someone to help you, make sure you keep this clear and take more and more ownership yourself as the project progresses. How much time do you have? Usually the first thing I ask is about the timeline for the project. It doesn’t matter how skilled you are, if you have a short window to get things done it’s better to get help - especially if this is your first cloud project. Having someone that knows the platform well can save you amazing amounts of time. If you have longer, then start with the training in the link above and once you feel confident, jump in. How complex is the project? If there are a lot of moving parts, it’s best to engage a partner. The reason is that certain interactions - particularly things like Service Bus or Data Integration  - can be quite different than what you may have encountered before. How many people do you have? I have a “pizza rule” about projects I’ve used in my career - if it takes over two pizzas to feed everyone on the project, it’s too big and will fail. That being said, one developer and a one-week deadline does not a good project make, usually. It’s best to have at least one architect (or someone in that role) guiding the project along, and at least two developers to work on a cloud project. That’s a generalization of course, since I’ve seen great software on Azure with one developer writing code all by herself, but for more complex projects, more (to a point) is better. The nice thing about bringing on a partner is that you don’t have to hire them full time - they help you and then they go away. How critical is the project? There’s no shame in using some help. If the platform is new, if the project is large and complex, and if it is critical to the business, you should engage a partner. That’s regardless of Cloud or anything else - get some help. You don’t want to hit your company’s bottom line in a negative way, but you have to innovate and get them a competitive advantage. Do your research, make sure the partner is qualified to help you, and get it done. Don’t let these questions scare you off. There are lots of projects you can implement on Windows and SQL Azure with nothing other than the Software Development Kit (SDK) that you get for free with Windows Azure. And assistance comes in many forms - sometimes just phone support, a friend you can ask. Microsoft Consulting Services or any of our great partners. You can get help on just the architecture piece or have them show you how to write the code. They’ll get involved as little or as much as you like.

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  • Log message Request and Response in ASP.NET WebAPI

    - by Fredrik N
    By logging both incoming and outgoing messages for services can be useful in many scenarios, such as debugging, tracing, inspection and helping customers with request problems etc.  I have a customer that need to have both incoming and outgoing messages to be logged. They use the information to see strange behaviors and also to help customers when they call in  for help (They can by looking in the log see if the customers sends in data in a wrong or strange way).   Concerns Most loggings in applications are cross-cutting concerns and should not be  a core concern for developers. Logging messages like this:   // GET api/values/5 public string Get(int id) { //Cross-cutting concerns Log(string.Format("Request: GET api/values/{0}", id)); //Core-concern var response = DoSomething(); //Cross-cutting concerns Log(string.Format("Reponse: GET api/values/{0}\r\n{1}", id, response)); return response; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } will only result in duplication of code, and unnecessarily concerns for the developers to be aware of, if they miss adding the logging code, no logging will take place. Developers should focus on the core-concern, not the cross-cutting concerns. By just focus on the core-concern the above code will look like this: // GET api/values/5 public string Get(int id) { return DoSomething(); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The logging should then be placed somewhere else so the developers doesn’t need to focus care about the cross-concern. Using Message Handler for logging There are different ways we could place the cross-cutting concern of logging message when using WebAPI. We can for example create a custom ApiController and override the ApiController’s ExecutingAsync method, or add a ActionFilter, or use a Message Handler. The disadvantage with custom ApiController is that we need to make sure we inherit from it, the disadvantage of ActionFilter, is that we need to add the filter to the controllers, both will modify our ApiControllers. By using a Message Handler we don’t need to do any changes to our ApiControllers. So the best suitable place to add our logging would be in a custom Message Handler. A Message Handler will be used before the HttpControllerDispatcher (The part in the WepAPI pipe-line that make sure the right controller is used and called etc). Note: You can read more about message handlers here, it will give you a good understanding of the WebApi pipe-line. To create a Message Handle we can inherit from the DelegatingHandler class and override the SendAsync method: public class MessageHandler : DelegatingHandler { protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken) { return base.SendAsync(request, cancellationToken); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   If we skip the call to the base.SendAsync our ApiController’s methods will never be invoked, nor other Message Handlers. Everything placed before base.SendAsync will be called before the HttpControllerDispatcher (before WebAPI will take a look at the request which controller and method it should be invoke), everything after the base.SendAsync, will be executed after our ApiController method has returned a response. So a message handle will be a perfect place to add cross-cutting concerns such as logging. To get the content of our response within a Message Handler we can use the request argument of the SendAsync method. The request argument is of type HttpRequestMessage and has a Content property (Content is of type HttpContent. The HttpContent has several method that can be used to read the incoming message, such as ReadAsStreamAsync, ReadAsByteArrayAsync and ReadAsStringAsync etc. Something to be aware of is what will happen when we read from the HttpContent. When we read from the HttpContent, we read from a stream, once we read from it, we can’t be read from it again. So if we read from the Stream before the base.SendAsync, the next coming Message Handlers and the HttpControllerDispatcher can’t read from the Stream because it’s already read, so our ApiControllers methods will never be invoked etc. The only way to make sure we can do repeatable reads from the HttpContent is to copy the content into a buffer, and then read from that buffer. This can be done by using the HttpContent’s LoadIntoBufferAsync method. If we make a call to the LoadIntoBufferAsync method before the base.SendAsync, the incoming stream will be read in to a byte array, and then other HttpContent read operations will read from that buffer if it’s exists instead directly form the stream. There is one method on the HttpContent that will internally make a call to the  LoadIntoBufferAsync for us, and that is the ReadAsByteArrayAsync. This is the method we will use to read from the incoming and outgoing message. public abstract class MessageHandler : DelegatingHandler { protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken) { var requestMessage = await request.Content.ReadAsByteArrayAsync(); var response = await base.SendAsync(request, cancellationToken); var responseMessage = await response.Content.ReadAsByteArrayAsync(); return response; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The above code will read the content of the incoming message and then call the SendAsync and after that read from the content of the response message. The following code will add more logic such as creating a correlation id to combine the request with the response, and create a log entry etc: public abstract class MessageHandler : DelegatingHandler { protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken) { var corrId = string.Format("{0}{1}", DateTime.Now.Ticks, Thread.CurrentThread.ManagedThreadId); var requestInfo = string.Format("{0} {1}", request.Method, request.RequestUri); var requestMessage = await request.Content.ReadAsByteArrayAsync(); await IncommingMessageAsync(corrId, requestInfo, requestMessage); var response = await base.SendAsync(request, cancellationToken); var responseMessage = await response.Content.ReadAsByteArrayAsync(); await OutgoingMessageAsync(corrId, requestInfo, responseMessage); return response; } protected abstract Task IncommingMessageAsync(string correlationId, string requestInfo, byte[] message); protected abstract Task OutgoingMessageAsync(string correlationId, string requestInfo, byte[] message); } public class MessageLoggingHandler : MessageHandler { protected override async Task IncommingMessageAsync(string correlationId, string requestInfo, byte[] message) { await Task.Run(() => Debug.WriteLine(string.Format("{0} - Request: {1}\r\n{2}", correlationId, requestInfo, Encoding.UTF8.GetString(message)))); } protected override async Task OutgoingMessageAsync(string correlationId, string requestInfo, byte[] message) { await Task.Run(() => Debug.WriteLine(string.Format("{0} - Response: {1}\r\n{2}", correlationId, requestInfo, Encoding.UTF8.GetString(message)))); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   The code above will show the following in the Visual Studio output window when the “api/values” service (One standard controller added by the default WepAPI template) is requested with a Get http method : 6347483479959544375 - Request: GET http://localhost:3208/api/values 6347483479959544375 - Response: GET http://localhost:3208/api/values ["value1","value2"] .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   Register a Message Handler To register a Message handler we can use the Add method of the GlobalConfiguration.Configration.MessageHandlers in for example Global.asax: public class WebApiApplication : System.Web.HttpApplication { protected void Application_Start() { GlobalConfiguration.Configuration.MessageHandlers.Add(new MessageLoggingHandler()); ... } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   Summary By using a Message Handler we can easily remove cross-cutting concerns like logging from our controllers. You can also find the source code used in this blog post on ForkCan.com, feel free to make a fork or add comments, such as making the code better etc. Feel free to follow me on twitter @fredrikn if you want to know when I will write other blog posts etc.

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  • Auto-cancel reason not found (6, 13906)

    - by Rajesh Sharma
    There are many errors in the application which are never invoked because of appropriate application configuration done at the time of implementation by the solution architects. So typically, as an application end user you would never stumble upon such errors. But what if the application administrator inadvertently changes the configuration/setup in the development, test, QA, or production environment? This is the time when you as an end user are introduced to a brand-new error for which you may not have a clue or understanding to what it means and neither the access/privilege to rectify it.    In this post we'll focus on one such error '6, 13906 - Auto-cancel reason not found'.   You get this error if you have not defined a Bill (Segment) Cancel Reason (Admin Menu, B, Bill Cancel Reason) code with System Default value of Turn off auto-cancel.   Consider a scenario when you are about to final bill an 'Account' for which the bill period's cut-off date you selected is falling on or after the Service Agreement's (SA) end/stop date (basically SA is Stopped with a date earlier than it was billed previously). And for the same 'Account' either: Bill segments exists that end after the SA's end date OR Non-closing bill segments exists that end on the SA's end date (OR closing bill segments that do not end on SA's end date or do not exist at all - remember closing/final bill segment is generated if the SA is in Stopped status).   CC&B detects such scenario and attempts to cancel all such violating bill segments automatically, but NOT if you are generating the bill Online. If online, the system assumes that you know what you are doing, and prompts you with error 2, 13716 - Bill segments that violate the SA (%1) End Date (%2) exist to take necessary action.   If in batch, system automatically cancels these kinds of bill segment(s).   Since this happens in the background, you have to define within the application which System Default Bill (Segment) cancellation reason code identified as Turn off auto-cancel, should be used by the process when it attempts to cancel any such violating bill segments (You already know that you cannot cancel a bill segment without giving a reason for cancellation).   So what exactly happens during batch billing?   Bill Segment generation routine at first determines billing eligibility of the service agreement being billed. One of the billing eligibility criteria is to check the SA's previous bill segments which have end dates greater than the current cut-off date/end date. Technically, the routine retrieves a count of such violating bill segments.     SELECT COUNT (*) FROM CI_BSEG WHERE SA_ID = :SA-ID AND BSEG_STAT_FLG = '50' -- Frozen AND END_DT IS NOT NULL AND (END_DT > '03-JUN-2010' -- Bill segment greater than SA's End Date OR OR (END_DT = '03-JUN-2010' AND CLOSING_BSEG_SW = 'N')) -- Non-closing bill segment ending on SA's end date   If the count is greater than zero, Bill segment generation routine executes another program to auto-cancel such bill segments. Auto-cancel program retrieves the 'Bill Cancel Reason' code which is identified as Turn off auto-cancel. Retrieved cancel reason code is then placed on the bill segments that are being cancelled automatically.   During this process if the routine fails to determine the bill cancel reason code having System Default Turn off auto-cancel because it was not been configured, you get a bill exception 6, 13906 - Auto-cancel reason not found.   Also note that duplicate or multiple System Default codes identified as Turn off auto-cancel are not allowed. CC&B would complain with an error 2, 54201.   Duplicate validation/check is also performed within Auto-cancel routine, if suppose for test purposes you executed a DML statement updating CI_BILL_CAN_RSN.BSCAN_SYS_DFLT_FLG with a value 'T'.

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  • Designing for the future

    - by Dennis Vroegop
    User interfaces and user experience design is a fast moving field. It’s something that changes pretty quick: what feels fresh today will look outdated tomorrow. I remember the day I first got a beta version of Windows 95 and I felt swept away by the user interface of the OS. It felt so modern! If I look back now, it feels old. Well, it should: the design is 17 years old which is an eternity in our field. Of course, this is not limited to UI. Same goes for many industries. I want you to think back of the cars that amazed you when you were in your teens (if you are in your teens then this may not apply to you). Didn’t they feel like part of the future? Didn’t you think that this was the ultimate in designs? And aren’t those designs hopelessly outdated today (again, depending on your age, it may just be me)? Let’s review the Win95 design: And let’s compare that to Windows 7: There are so many differences here, I wouldn’t even know where to start explaining them. The general feeling however is one of more usability: studies have shown Windows 7 is much easier to understand for new users than the older versions of Windows did. Of course, experienced Windows users didn’t like it: people are usually afraid of changes and like to stick to what they know. But for new users this was a huge improvement. And that is what UX design is all about: make a product easier to use, with less training required and make users feel more productive. Still, there are areas where this doesn’t hold up. There are plenty examples of designs from the past that are still fresh today. But if you look closely at them, you’ll notice some subtle differences. This differences are what keep the designs fresh. A good example is the signs you’ll find on the road. They haven’t changed much over the years (otherwise people wouldn’t recognize them anymore) but they have been changing gradually to reflect changes in traffic. The same goes for computer interfaces. With each new product or version of a product, the UI and UX is changed gradually. Every now and then however, a bigger change is needed. Just think about the introduction of the Ribbon in Microsoft Office 2007: the whole UI was redesigned. A lot of old users (not in age, but in times of using older versions) didn’t like it a bit, but new users or casual users seem to be more efficient using the product. Which, of course, is exactly the reason behind the changes. I believe that a big engine behind the changes in User Experience design has been the web. In the old days (i.e. before the explosion of the internet) user interface design in Windows applications was limited to choosing the margins between your battleship gray buttons. When the web came along, and especially the web 2.0 where the browsers started to act more and more as application platforms, designers stepped in and made a huge impact. In the browser, they could do whatever they wanted. In the beginning this was limited to the darn blink tag but gradually people really started to think about UX. Even more so: the design of the UI and the whole experience was taken away from the developers and put into the hands of people who knew what they were doing: UX designers. This caused some problems. Everyone who has done a web project in the early 2000’s must have had the same experience: the designers give you a set of Photoshop files and tell you to translate it to HTML. Which, of course, is very hard to do. However, with new tooling and new standards this became much easier. The latest version of HTML and CSS has taken the responsibility for the design away from the developers and placed them in the capable hands of the designers. And that’s where that responsibility belongs, after all, I don’t want a designer to muck around in my c# code just as much as he or she doesn’t want me to poke in the sites style definitions. This change in responsibilities resulted in good looking but more important: better thought out user interfaces in websites. And when websites became more and more interactive, people started to expect the same sort of look and feel from their desktop applications. But that didn’t really happen. Most business applications still have that battleship gray look and feel. Ok, they may use a different color but we’re not talking colors here but usability. Now, you may not be able to read the Dutch captions, but even if you did you wouldn’t understand what was going on. At least, not when you first see it. You have to scan the screen, read all the labels, see how they are related to the other elements on the screen and then figure out what they do. If you’re an experienced user of this application however, this might be a good thing: you know what to do and you get all the information you need in one single screen. But for most applications this isn’t the case. A lot of people only use their computer for a limited time a day (a weird concept for me, but it happens) and need it to get something done and then get on with their lives. For them, a user interface experience like the above isn’t working. (disclaimer: I just picked a screenshot, I am not saying this is bad software but it is an example of about 95% of the Windows applications out there). For the knowledge worker, this isn’t a problem. They use one or two systems and they know exactly what they need to do to achieve their goal. They don’t want any clutter on their screen that distracts them from their task, they just want to be as efficient as possible. When they know the systems they are very productive. The point is, how long does it take to become productive? And: could they be even more productive if the UX was better? Are there things missing that they don’t know about? Are there better ways to achieve what they want to achieve? Also: could a system be designed in such a way that it is not only much more easy to work with but also less tiring? in the example above you need to switch between the keyboard and mouse a lot, something that we now know can be very tiring. The goal of most applications (being client apps or websites on any kind of device) is to provide information. Information is data that when given to the right people, on the right time, in the right place and when it is correct adds value for that person (please, remember that definition: I still hear the statement “the information was wrong” which doesn’t make sense: data can be wrong, information cannot be). So if a system provides data, how can we make sure the chances of becoming information is as high as possible? A good example of a well thought-out system that attempts this is the Zune client. It is a very good application, and I think the UX is much better than it’s main competitor iTunes. Have a look at both: On the left you see the iTunes screenshot, on the right the Zune. As you notice, the Zune screen has more images but less chrome (chrome being visuals not part of the data you want to show, i.e. edges around buttons). The whole thing is text oriented or image oriented, where that text or image is part of the information you need. What is important is big, what’s less important is smaller. Yet, everything you need to know at that point is present and your attention is drawn immediately to what you’re trying to achieve: information about music. You can easily switch between the content on your machine and content on your Zune player but clicking on the image of the player. But if you didn’t know that, you’d find out soon enough: the whole UX is designed in such a way that it invites you to play around. So sooner or later (probably sooner) you’d click on that image and you would see what it does. In the iTunes version it’s harder to find: the discoverability is a lot lower. For inexperienced people the Zune player feels much more natural than the iTunes player, and they get up to speed a lot faster. How does this all work? Why is this UX better? The answer lies in a project from Microsoft with the codename (it seems to be becoming the official name though) “Metro”. Metro is a design language, based on certain principles. When they thought about UX they took a good long look around them and went out in search of metaphors. And they found them. The team noticed that signage in streets, airports, roads, buildings and so on are usually very clear and very precise. These signs give you the information you need and nothing more. It’s simple, clearly understood and fast to understand. A good example are airport signs. Airports can be intimidating places, especially for the non-experienced traveler. In the early 1990’s Amsterdam Airport Schiphol decided to redesign all the signage to make the traveller feel less disoriented. They developed a set of guidelines for signs and implemented those. Soon, most airports around the world adopted these ideas and you see variations of the Dutch signs everywhere on the globe. The signs are text-oriented. Yes, there are icons explaining what it all means for the people who can’t read or don’t understand the language, but the basic sign language is text. It’s clear, it’s high-contrast and it’s easy to understand. One look at the sign and you know where to go. The only thing I don’t like is the green sign pointing to the emergency exit, but since this is the default style for emergency exits I understand why they did this. If you look at the Zune UI again, you’ll notice the similarities. Text oriented, little or no icons, clear usage of fonts and all the information you need. This design language has a set of principles: Clean, light, open and fast Content, not chrome Soulful and alive These are just a couple of the principles, you can read the whole philosophy behind Metro for Windows Phone 7 here. These ideas seem to work. I love my Windows Phone 7. It’s easy to use, it’s clear, there’s no clutter that I do not need. It works for me. And I noticed it works for a lot of other people as well, especially people who aren’t as proficient with computers as I am. You see these ideas in a lot other places. Corning, a manufacturer of glass, has made a video of possible usages of their products. It’s their glimpse into the future. You’ll notice that a lot of the UI in the screens look a lot like what Microsoft is doing with Metro (not coincidentally Corning is the supplier for the Gorilla glass display surface on the new SUR40 device (or Surface v2.0 as a lot of people call it)). The idea behind this vision is that data should be available everywhere where you it. Systems should be available at all times and data is presented in a clear and light manner so that you can turn that data into information. You don’t need a lot of fancy animations that only distract from the data. You want the data and you want it fast. Have a look at this truly inspiring video that made: This is what I believe the future will look like. Of course, not everything is possible, or even desirable. But it is a nice way to think about the future . I feel very strongly about designing applications in such a way that they add value to the user. Designing applications that turn data into information. Applications that make the user feel happy to use them. So… when are you going to drop the battleship-gray designs? Tags van Technorati: surface,design,windows phone 7,wp7,metro

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  • Guest (and occasional co-host) on Jesse Liberty's Yet Another Podcast

    - by Jon Galloway
    I was a recent guest on Jesse Liberty's Yet Another Podcast talking about the latest Visual Studio, ASP.NET and Azure releases. Download / Listen: Yet Another Podcast #75–Jon Galloway on ASP.NET/ MVC/ Azure Co-hosted shows: Jesse's been inviting me to co-host shows and I told him I'd show up when I was available. It's a nice change to be a drive-by co-host on a show (compared with the work that goes into organizing / editing / typing show notes for Herding Code shows). My main focus is on Herding Code, but it's nice to pop in and talk to Jesse's excellent guests when it works out. Some shows I've co-hosted over the past year: Yet Another Podcast #76–Glenn Block on Node.js & Technology in China Yet Another Podcast  #73 - Adam Kinney on developing for Windows 8 with HTML5 Yet Another Podcast #64 - John Papa & Javascript Yet Another Podcast #60 - Steve Sanderson and John Papa on Knockout.js Yet Another Podcast #54–Damian Edwards on ASP.NET Yet Another Podcast #53–Scott Hanselman on Blogging Yet Another Podcast #52–Peter Torr on Windows Phone Multitasking Yet Another Podcast #51–Shawn Wildermuth: //build, Xaml Programming & Beyond And some more on the way that haven't been released yet. Some of these I'm pretty quiet, on others I get wacky and hassle the guests because, hey, not my podcast so not my problem. Show notes from the ASP.NET / MVC / Azure show: What was just released Visual Studio 2012 Web Developer features ASP.NET 4.5 Web Forms Strongly Typed data controls Data access via command methods Similar Binding syntax to ASP.NET MVC Some context: Damian Edwards and WebFormsMVP Two questions from Jesse: Q: Are you making this harder or more complicated for Web Forms developers? Short answer: Nothing's removed, it's just a new option History of SqlDataSource, ObjectDataSource Q: If I'm using some MVC patterns, why not just move to MVC? Short answer: This works really well in hybrid applications, doesn't require a rewrite Allows sharing models, validation, other code between Web Forms and MVC ASP.NET MVC Adaptive Rendering (oh, also, this is in Web Forms 4.5 as well) Display Modes Mobile project template using jQuery Mobile OAuth login to allow Twitter, Google, Facebook, etc. login Jon (and friends') MVC 4 book on the way: Professional ASP.NET MVC 4 Windows 8 development Jesse and Jon announce they're working on a new book: Pro Windows 8 Development with XAML and C# Jon and Jesse agree that it's nice to be able to write Windows 8 applications using the same skills they picked up for Silverlight, WPF, and Windows Phone development. Compare / contrast ASP.NET MVC and Windows 8 development Q: Does ASP.NET and HTML5 development overlap? Jon thinks they overlap in the MVC world because you're writing HTML views without controls Jon describes how his web development career moved from a preoccupation with server code to a focus on user interaction, which occurs in the browser Jon mentions his NDC Oslo presentation on Learning To Love HTML as Beautiful Code Q: How do you apply C# / XAML or HTML5 skills to Windows 8 development? Q: If I'm a XAML programmer, what's the learning curve on getting up to speed on ASP.NET MVC? Jon describes the difference in application lifecycle and state management Jon says it's nice that web development is really interactive compared to application development Q: Can you learn MVC by reading a book? Or is it a lot bigger than that? What is Azure, and why would I use it? Jon describes the traditional Azure platform mode and how Azure Web Sites fits in Q: Why wouldn't Jesse host his blog on Azure Web Sites? Domain names on Azure Web Sites File hosting options Q: Is Azure just another host? How is it different from any of the other shared hosting options? A: Azure gives you the ability to scale up or down whenever you want A: Other services are available if or when you want them

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  • Silverlight Cream for February 10, 2011 -- #1045

    - by Dave Campbell
    In this Issue: Mark Monster, Jaime Rodriguez, Mark Hopkins, WindowsPhoneGeek, David Anson, Jesse Liberty, Jeremy Likness, Martin Krüger(-2-), Beth Massi, Joost van Schaik, Laurent Bugnion, and Arik Poznanski. Above the Fold: Silverlight: "Parsing the Visual Tree with LINQ" Jeremy Likness WP7: "Silverlight-ready PNG encoder implementation shows one way to use .NET IEnumerables effectively" David Anson Lightswitch: "How to Send Automated Appointments from a LightSwitch Application" Beth Massi Shoutouts: Be sure to visit SilverlightShow... check out their top hits last week: SilverlightShow for Jan 31- Feb 06, 2011 Jaime Rodriguez has a post up that all the WP7 folks will be interested in: FAQ about copy paste functionality in upcoming release From SilverlightCream.com: Make use of WCF FaultContracts in Silverlight clients Mark Monster takes a shot at answering “The remote server returned an error: NotFound” while connecting to a WCF Service problem we all see. Communication between HTML in WebBrowser and Silverlight app Jaime Rodriguez responds to questions he received about communication between HTML and SIlverlight with this post about the bi-directional communication between the control and HTML. WP7 - Real Apps, Real Code Mark Hopkins has a post up about some WP7 starter kits that you can get all the source for and actually download the app from the Marketplace first to see if it interests you! WP7 AboutPrompt in depth WindowsPhoneGeek has this cool post up about the AboutPrompt from the Coding4Fun toolkit in detail... great diagrams showing where all the elements are and code examples with images. Silverlight-ready PNG encoder implementation shows one way to use .NET IEnumerables effectively David Anson describes why he took it upon himself to write his own png encoder for Silverlight... and we all thank him for doing so and providing us with the code! Navigation 101–Cancelling Navigation Jesse Liberty's latest WP7 From Scratch episode is up (number 32), and he's talking about Navigation and how to cancel it if you need to. Parsing the Visual Tree with LINQ Jeremy Likness demonstrates using LINQ to rat out information in the visual tree of your XAML. To Quote Jeremy: "you can easily check for intersections between elements and find any type of element no matter how deep within the tree it is". SpriteAnimationBehavior Martin Krüger has a couple more fun things in the Expression Gallery that I haven't discussed. First up is a behavior that animates up to 999 images and lets you control the FramesPerSecond... great demo on the ExpressionGallery to play with. Second alternative: Storyboard should not start before the Silverlight application is loaded Martin Krüger's latest is a way to programmatically wait for the Loaded event so that you know you can let your animations fly. How to Send Automated Appointments from a LightSwitch Application Beth Massi's latest Lightswitch post follows up her Outlook automation one with sending appointments using the standard iCalendar format... all the code included of course. The case for the Bindable Application Bar for Windows Phone 7 Joost van Schaik posts about a bindable Application Bar for your WP7 apps... grab the code and don't leave home without it :) MVVM Light V4 preview (BL0014) release notes Laurent Bugnion posted an update to MVVMLight to Codeplex a couple days ago. This is an early preview of what he plans on having in version 4, so check out the post for what's new and fun. Search Digg on Windows Phone 7 Arik Poznanski followed up his RSS post from last week with this one on searching Digg on WP7... and he's discussing and providing a utility class for doing it. Stay in the 'Light! Twitter SilverlightNews | Twitter WynApse | WynApse.com | Tagged Posts | SilverlightCream Join me @ SilverlightCream | Phoenix Silverlight User Group Technorati Tags: Silverlight    Silverlight 3    Silverlight 4    Windows Phone MIX10

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  • Silverlight Cream for May 13, 2010 -- #861

    - by Dave Campbell
    In this Issue: Sigurd Snørteland, Jeff Prosise, DaveDev, Joe Zhou, Chris Eargle, John Papa(-2-, -3-), and David Anson(-2-). Shoutouts: In with the links I've listed below, Sigurd Snørteland also sent a link to this app he's working on which is actually pretty cool to see: ZuneLight. The code is not yet available. He also has a no-code demo of a Silverlight Media Center Pieter Voloshyn, Luiz Thadeu, and Jhun Iti have a very nice Silverlight image editor up: Thumba From SilverlightCream.com: WP7 - Silverlight on mobile Sigurd Snørteland submitted some links for me that have been translated to English from his blog. I hope the pages come out good because he's got a lot of good stuff on there. This one has a link to a presentation he did, and 4 projects you can load up in the emulator that he's converted to the phone: weather, worldclock, coverflow, and solitaire ... pretty cool... thanks for the links Sigurd! Understanding Page Orientation in Silverlight for Windows Phone Jeff Prosise has a really nice post up on page orientation in WP7 ... what it means to your app, how to detect it, and example code for what to do then... also love a quote by Jeff: "Silverlight for Windows Phone is the hottest thing since color TV" Why you should check out Expression Blend Behaviors when using Silverlight DaveDev has a post up describing Behaviors and why we should use them, plus tons of external links to resources, blogs, videos... all good stuff... Fiddler inspector for WCF Silverlight Polling Duplex and WCF RIA Joe Zhou announces and provides a link to a new Fiddler inspector that understands the framing in Polling Duplex and also raw binary xml and binary SOAP. Windows Phone Controls v0.7 Chris Eargle reports the release of Version 0.7 of the Windows Phone Controls project on CodePlex ... this includes a Pivot Control and a Panorama Control... both very nicely done. Binding to Silverlight ComboBox and Using SelectedValue, SelectedValuePath and DisplayMemberPath John Papa responds to a user question and put up a nice post about binding to a ComboBox and then go from the selected item to some other property ... code included No More Boxes! Exploring the PathListBox (Silverlight TV #25) Silverlight TV 25 went up on Tuesday ... thought it was going to be Thursday?? anyway ... John Papa and Adam Kinney are discussing the PathListBox and looking at some cool demos thereof. Exposing SOAP, OData, and JSON Endpoints for RIA Services (Silverlight TV 26) Since today IS Thursday, we have a new Silverlight TV, number 26, and John Papa is chatting with Deepesh Mohnani of the WCF RIA Services team about exposing all sorts of endpoints... should be something in there for everybody :) Workaround for a Silverlight data binding bug affecting various scenarios - including DataGrid+ContextMenu David Anson details the rabbit-trail he and others on the team followed in response to a problem reported via Twitter where the binding on a DataGrid seemed off by a row(!) ... weird but true, validated, and SL3/4 are bug-for-bug compatible with this too! ... But David wouldn't leave us there.. he also has a workaround. Sharing the code for a simple Silverlight 4 REST-based cloud-oriented file management app for Azure and S3 David Anson had an opportunity to build an app he's wanted to build for a while and shares it with us: Blobstore -- a small, lightweight Silverlight 4 application that acts as a basic front-end for the Windows Azure Simple Data Storage and the Amazon Simple Storage Service (S3) -- and remember I said he shared the source :) Stay in the 'Light! Twitter SilverlightNews | Twitter WynApse | WynApse.com | Tagged Posts | SilverlightCream Join me @ SilverlightCream | Phoenix Silverlight User Group Technorati Tags: Silverlight    Silverlight 3    Silverlight 4    Windows Phone MIX10

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  • Odd MVC 4 Beta Razor Designer Issue

    - by Rick Strahl
    This post is a small cry for help along with an explanation of a problem that is hard to describe on twitter or even a connect bug and written in hopes somebody has seen this before and any ideas on what might cause this. Lots of helpful people had comments on Twitter for me, but they all assumed that the code doesn't run, which is not the case - it's a designer issue. A few days ago I started getting some odd problems in my MVC 4 designer for an app I've been working on for the past 2 weeks. Basically the MVC 4 Razor designer keeps popping me errors, about the call signature to various Html Helper methods being incorrect. It also complains about the ViewBag object and not supporting dynamic requesting to load assemblies into the project. Here's what the designer errors look like: You can see the red error underlines under the ViewBag and an Html Helper I plopped in at the top to demonstrate the behavior. Basically any HtmlHelper I'm accessing is showing the same errors. Note that the code *runs just fine* - it's just the designer that is complaining with Errors. What's odd about this is that *I think* this started only a few days ago and nothing consequential that I can think of has happened to the project or overall installations. These errors aren't critical since the code runs but pretty annoying especially if you're building and have .csHtml files open in Visual Studio mixing these fake errors with real compiler errors. What I've checked Looking at the errors it indeed looks like certain references are missing. I can't make sense of the Html Helpers error, but certainly the ViewBag dynamic error looks like System.Core or Microsoft.CSharp assemblies are missing. Rest assured they are there and the code DOES run just fine at runtime. This is a designer issue only. I went ahead and checked the namespaces that MVC has access to in Razor which lives in the Views folder's web.config file: /Views/web.config For good measure I added <system.web.webPages.razor> <host factoryType="System.Web.Mvc.MvcWebRazorHostFactory, System.Web.Mvc, <split for layout> Version=4.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" /> <pages pageBaseType="System.Web.Mvc.WebViewPage"> <namespaces> <add namespace="System.Web.Mvc" /> <add namespace="System.Web.Mvc.Ajax" /> <add namespace="System.Web.Mvc.Html" /> <add namespace="System.Web.Routing" /> <add namespace="System.Linq" /> <add namespace="System.Linq.Expressions" /> <add namespace="ClassifiedsBusiness" /> <add namespace="ClassifiedsWeb"/> <add namespace="Westwind.Utilities" /> <add namespace="Westwind.Web" /> <add namespace="Westwind.Web.Mvc" /> </namespaces> </pages> </system.web.webPages.razor> For good measure I added System.Linq and System.Linq.Expression on which some of the Html.xxxxFor() methods rely, but no luck. So, has anybody seen this before? Any ideas on what might be causing these issues only at design time rather, when the final compiled code runs just fine?© Rick Strahl, West Wind Technologies, 2005-2012Posted in Razor  MVC   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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  • Avoiding new operator in JavaScript -- the better way

    - by greengit
    Warning: This is a long post. Let's keep it simple. I want to avoid having to prefix the new operator every time I call a constructor in JavaScript. This is because I tend to forget it, and my code screws up badly. The simple way around this is this... function Make(x) { if ( !(this instanceof arguments.callee) ) return new arguments.callee(x); // do your stuff... } But, I need this to accept variable no. of arguments, like this... m1 = Make(); m2 = Make(1,2,3); m3 = Make('apple', 'banana'); The first immediate solution seems to be the 'apply' method like this... function Make() { if ( !(this instanceof arguments.callee) ) return new arguments.callee.apply(null, arguments); // do your stuff } This is WRONG however -- the new object is passed to the apply method and NOT to our constructor arguments.callee. Now, I've come up with three solutions. My simple question is: which one seems best. Or, if you have a better method, tell it. First – use eval() to dynamically create JavaScript code that calls the constructor. function Make(/* ... */) { if ( !(this instanceof arguments.callee) ) { // collect all the arguments var arr = []; for ( var i = 0; arguments[i]; i++ ) arr.push( 'arguments[' + i + ']' ); // create code var code = 'new arguments.callee(' + arr.join(',') + ');'; // call it return eval( code ); } // do your stuff with variable arguments... } Second – Every object has __proto__ property which is a 'secret' link to its prototype object. Fortunately this property is writable. function Make(/* ... */) { var obj = {}; // do your stuff on 'obj' just like you'd do on 'this' // use the variable arguments here // now do the __proto__ magic // by 'mutating' obj to make it a different object obj.__proto__ = arguments.callee.prototype; // must return obj return obj; } Third – This is something similar to second solution. function Make(/* ... */) { // we'll set '_construct' outside var obj = new arguments.callee._construct(); // now do your stuff on 'obj' just like you'd do on 'this' // use the variable arguments here // you have to return obj return obj; } // now first set the _construct property to an empty function Make._construct = function() {}; // and then mutate the prototype of _construct Make._construct.prototype = Make.prototype; eval solution seems clumsy and comes with all the problems of "evil eval". __proto__ solution is non-standard and the "Great Browser of mIsERY" doesn't honor it. The third solution seems overly complicated. But with all the above three solutions, we can do something like this, that we can't otherwise... m1 = Make(); m2 = Make(1,2,3); m3 = Make('apple', 'banana'); m1 instanceof Make; // true m2 instanceof Make; // true m3 instanceof Make; // true Make.prototype.fire = function() { // ... }; m1.fire(); m2.fire(); m3.fire(); So effectively the above solutions give us "true" constructors that accept variable no. of arguments and don't require new. What's your take on this. -- UPDATE -- Some have said "just throw an error". My response is: we are doing a heavy app with 10+ constructors and I think it'd be far more wieldy if every constructor could "smartly" handle that mistake without throwing error messages on the console.

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  • How to create a new WCF/MVC/jQuery application from scratch

    - by pjohnson
    As a corporate developer by trade, I don't get much opportunity to create from-the-ground-up web sites; usually it's tweaks, fixes, and new functionality to existing sites. And with hobby sites, I often don't find the challenges I run into with enterprise systems; usually it's starting from Visual Studio's boilerplate project and adding whatever functionality I want to play around with, rarely deploying outside my own machine. So my experience creating a new enterprise-level site was a bit dated, and the technologies to do so have come a long way, and are much more ready to go out of the box. My intention with this post isn't so much to provide any groundbreaking insights, but to just tie together a lot of information in one place to make it easy to create a new site from scratch. Architecture One site I created earlier this year had an MVC 3 front end and a WCF 4-driven service layer. Using Visual Studio 2010, these project types are easy enough to add to a new solution. I created a third Class Library project to store common functionality the front end and services layers both needed to access, for example, the DataContract classes that the front end uses to call services in the service layer. By keeping DataContract classes in a separate project, I avoided the need for the front end to have an assembly/project reference directly to the services code, a bit cleaner and more flexible of an SOA implementation. Consuming the service Even by this point, VS has given you a lot. You have a working web site and a working service, neither of which do much but are great starting points. To wire up the front end and the services, I needed to create proxy classes and WCF client configuration information. I decided to use the SvcUtil.exe utility provided as part of the Windows SDK, which you should have installed if you installed VS. VS also provides an Add Service Reference command since the .NET 1.x ASMX days, which I've never really liked; it creates several .cs/.disco/etc. files, some of which contained hardcoded URL's, adding duplicate files (*1.cs, *2.cs, etc.) without doing a good job of cleaning up after itself. I've found SvcUtil much cleaner, as it outputs one C# file (containing several proxy classes) and a config file with settings, and it's easier to use to regenerate the proxy classes when the service changes, and to then maintain all your configuration in one place (your Web.config, instead of the Service Reference files). I provided it a reference to a copy of my common assembly so it doesn't try to recreate the data contract classes, had it use the type List<T> for collections, and modified the output files' names and .NET namespace, ending up with a command like: svcutil.exe /l:cs /o:MyService.cs /config:MyService.config /r:MySite.Common.dll /ct:System.Collections.Generic.List`1 /n:*,MySite.Web.ServiceProxies http://localhost:59999/MyService.svc I took the generated MyService.cs file and drop it in the web project, under a ServiceProxies folder, matching the namespace and keeping it separate from classes I coded manually. Integrating the config file took a little more work, but only needed to be done once as these settings didn't often change. A great thing Microsoft improved with WCF 4 is configuration; namely, you can use all the default settings and not have to specify them explicitly in your config file. Unfortunately, SvcUtil doesn't generate its config file this way. If you just copy & paste MyService.config's contents into your front end's Web.config, you'll copy a lot of settings you don't need, plus this will get unwieldy if you add more services in the future, each with its own custom binding. Really, as the only mandatory settings are the endpoint's ABC's (address, binding, and contract) you can get away with just this: <system.serviceModel>  <client>    <endpoint address="http://localhost:59999/MyService.svc" binding="wsHttpBinding" contract="MySite.Web.ServiceProxies.IMyService" />  </client></system.serviceModel> By default, the services project uses basicHttpBinding. As you can see, I switched it to wsHttpBinding, a more modern standard. Using something like netTcpBinding would probably be faster and more efficient since the client & service are both written in .NET, but it requires additional server setup and open ports, whereas switching to wsHttpBinding is much simpler. From an MVC controller action method, I instantiated the client, and invoked the method for my operation. As with any object that implements IDisposable, I wrapped it in C#'s using() statement, a tidy construct that ensures Dispose gets called no matter what, even if an exception occurs. Unfortunately there are problems with that, as WCF's ClientBase<TChannel> class doesn't implement Dispose according to Microsoft's own usage guidelines. I took an approach similar to Technology Toolbox's fix, except using partial classes instead of a wrapper class to extend the SvcUtil-generated proxy, making the fix more seamless from the controller's perspective, and theoretically, less code I have to change if and when Microsoft fixes this behavior. User interface The MVC 3 project template includes jQuery and some other common JavaScript libraries by default. I updated the ones I used to the latest versions using NuGet, available in VS via the Tools > Library Package Manager > Manage NuGet Packages for Solution... > Updates. I also used this dialog to remove packages I wasn't using. Given that it's smart enough to know the difference between the .js and .min.js files, I was hoping it would be smart enough to know which to include during build and publish operations, but this doesn't seem to be the case. I ended up using Cassette to perform the minification and bundling of my JavaScript and CSS files; ASP.NET 4.5 includes this functionality out of the box. The web client to web server link via jQuery was easy enough. In my JavaScript function, unobtrusively wired up to a button's click event, I called $.ajax, corresponding to an action method that returns a JsonResult, accomplished by passing my model class to the Controller.Json() method, which jQuery helpfully translates from JSON to a JavaScript object.$.ajax calls weren't perfectly straightforward. I tried using the simpler $.post method instead, but ran into trouble without specifying the contentType parameter, which $.post doesn't have. The url parameter is simple enough, though for flexibility in how the site is deployed, I used MVC's Url.Action method to get the URL, then sent this to JavaScript in a JavaScript string variable. If the request needed input data, I used the JSON.stringify function to convert a JavaScript object with the parameters into a JSON string, which MVC then parses into strongly-typed C# parameters. I also specified "json" for dataType, and "application/json; charset=utf-8" for contentType. For success and error, I provided my success and error handling functions, though success is a bit hairier. "Success" in this context indicates whether the HTTP request succeeds, not whether what you wanted the AJAX call to do on the web server was successful. For example, if you make an AJAX call to retrieve a piece of data, the success handler will be invoked for any 200 OK response, and the error handler will be invoked for failed requests, e.g. a 404 Not Found (if the server rejected the URL you provided in the url parameter) or 500 Internal Server Error (e.g. if your C# code threw an exception that wasn't caught). If an exception was caught and handled, or if the data requested wasn't found, this would likely go through the success handler, which would need to do further examination to verify it did in fact get back the data for which it asked. I discuss this more in the next section. Logging and exception handling At this point, I had a working application. If I ran into any errors or unexpected behavior, debugging was easy enough, but of course that's not an option on public web servers. Microsoft Enterprise Library 5.0 filled this gap nicely, with its Logging and Exception Handling functionality. First I installed Enterprise Library; NuGet as outlined above is probably the best way to do so. I needed a total of three assembly references--Microsoft.Practices.EnterpriseLibrary.ExceptionHandling, Microsoft.Practices.EnterpriseLibrary.ExceptionHandling.Logging, and Microsoft.Practices.EnterpriseLibrary.Logging. VS links with the handy Enterprise Library 5.0 Configuration Console, accessible by right-clicking your Web.config and choosing Edit Enterprise Library V5 Configuration. In this console, under Logging Settings, I set up a Rolling Flat File Trace Listener to write to log files but not let them get too large, using a Text Formatter with a simpler template than that provided by default. Logging to a different (or additional) destination is easy enough, but a flat file suited my needs. At this point, I verified it wrote as expected by calling the Microsoft.Practices.EnterpriseLibrary.Logging.Logger.Write method from my C# code. With those settings verified, I went on to wire up Exception Handling with Logging. Back in the EntLib Configuration Console, under Exception Handling, I used a LoggingExceptionHandler, setting its Logging Category to the category I already had configured in the Logging Settings. Then, from code (e.g. a controller's OnException method, or any action method's catch block), I called the Microsoft.Practices.EnterpriseLibrary.ExceptionHandling.ExceptionPolicy.HandleException method, providing the exception and the exception policy name I had configured in the Exception Handling Settings. Before I got this configured correctly, when I tried it out, nothing was logged. In working with .NET, I'm used to seeing an exception if something doesn't work or isn't set up correctly, but instead working with these EntLib modules reminds me more of JavaScript (before the "use strict" v5 days)--it just does nothing and leaves you to figure out why, I presume due in part to the listener pattern Microsoft followed with the Enterprise Library. First, I verified logging worked on its own. Then, verifying/correcting where each piece wires up to the next resolved my problem. Your C# code calls into the Exception Handling module, referencing the policy you pass the HandleException method; that policy's configuration contains a LoggingExceptionHandler that references a logCategory; that logCategory should be added in the loggingConfiguration's categorySources section; that category references a listener; that listener should be added in the loggingConfiguration's listeners section, which specifies the name of the log file. One final note on error handling, as the proper way to handle WCF and MVC errors is a whole other very lengthy discussion. For AJAX calls to MVC action methods, depending on your configuration, an exception thrown here will result in ASP.NET'S Yellow Screen Of Death being sent back as a response, which is at best unnecessarily and uselessly verbose, and at worst a security risk as the internals of your application are exposed to potential hackers. I mitigated this by overriding my controller's OnException method, passing the exception off to the Exception Handling module as above. I created an ErrorModel class with as few properties as possible (e.g. an Error string), sending as little information to the client as possible, to both maximize bandwidth and mitigate risk. I then return an ErrorModel in JSON format for AJAX requests: if (filterContext.HttpContext.Request.IsAjaxRequest()){    filterContext.Result = Json(new ErrorModel(...));    filterContext.ExceptionHandled = true;} My $.ajax calls from the browser get a valid 200 OK response and go into the success handler. Before assuming everything is OK, I check if it's an ErrorModel or a model containing what I requested. If it's an ErrorModel, or null, I pass it to my error handler. If the client needs to handle different errors differently, ErrorModel can contain a flag, error code, string, etc. to differentiate, but again, sending as little information back as possible is ideal. Summary As any experienced ASP.NET developer knows, this is a far cry from where ASP.NET started when I began working with it 11 years ago. WCF services are far more powerful than ASMX ones, MVC is in many ways cleaner and certainly more unit test-friendly than Web Forms (if you don't consider the code/markup commingling you're doing again), the Enterprise Library makes error handling and logging almost entirely configuration-driven, AJAX makes a responsive UI more feasible, and jQuery makes JavaScript coding much less painful. It doesn't take much work to get a functional, maintainable, flexible application, though having it actually do something useful is a whole other matter.

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  • More Animation - Self Dismissing Dialogs

    - by Duncan Mills
    In my earlier articles on animation, I discussed various slide, grow and  flip transitions for items and containers.  In this article I want to discuss a fade animation and specifically the use of fades and auto-dismissal for informational dialogs.  If you use a Mac, you may be familiar with Growl as a notification system, and the nice way that messages that are informational just fade out after a few seconds. So in this blog entry I wanted to discuss how we could make an ADF popup behave in the same way. This can be an effective way of communicating information to the user without "getting in the way" with modal alerts. This of course, has been done before, but everything I've seen previously requires something like JQuery to be in the mix when we don't really need it to be.  The solution I've put together is nice and generic and will work with either <af:panelWindow> or <af:dialog> as a the child of the popup. In terms of usage it's pretty simple to use we  just need to ensure that the popup itself has clientComponent is set to true and includes the animation JavaScript (animateFadingPopup) on a popupOpened event: <af:popup id="pop1" clientComponent="true">   <af:panelWindow title="A Fading Message...">    ...  </af:panelWindow>   <af:clientListener method="animateFadingPopup" type="popupOpened"/> </af:popup>   The popup can be invoked in the normal way using showPopupBehavior or JavaScript, no special code is required there. As a further twist you can include an additional clientAttribute called preFadeDelay to define a delay before the fade itself starts (the default is 5 seconds) . To set the delay to just 2 seconds for example: <af:popup ...>   ...   <af:clientAttribute name="preFadeDelay" value="2"/>   <af:clientListener method="animateFadingPopup" type="popupOpened"/>  </af:popup> The Animation Styles  As before, we have a couple of CSS Styles which define the animation, I've put these into the skin in my case, and, as in the other articles, I've only defined the transitions for WebKit browsers (Chrome, Safari) at the moment. In this case, the fade is timed at 5 seconds in duration. .popupFadeReset {   opacity: 1; } .popupFadeAnimate {   opacity: 0;   -webkit-transition: opacity 5s ease-in-out; } As you can see here, we are achieving the fade by simply setting the CSS opacity property. The JavaScript The final part of the puzzle is, of course, the JavaScript, there are four functions, these are generic (apart from the Style names which, if you've changed above, you'll need to reflect here): The initial function invoked from the popupOpened event,  animateFadingPopup which starts a timer and provides the initial delay before we start to fade the popup. The function that applies the fade animation to the popup - initiatePopupFade. The callback function - closeFadedPopup used to reset the style class and correctly hide the popup so that it can be invoked again and again.   A utility function - findFadeContainer, which is responsible for locating the correct child component of the popup to actually apply the style to. Function - animateFadingPopup This function, as stated is the one hooked up to the popupOpened event via a clientListener. Because of when the code is called it does not actually matter how you launch the popup, or if the popup is re-used from multiple places. All usages will get the fade behavior. /**  * Client listener which will kick off the animation to fade the dialog and register  * a callback to correctly reset the popup once the animation is complete  * @param event  */ function animateFadingPopup(event) { var fadePopup = event.getSource();   var fadeCandidate = false;   //Ensure that the popup is initially Opaque   //This handles the situation where the user has dismissed   //the popup whilst it was in the process of fading   var fadeContainer = findFadeContainer(fadePopup);   if (fadeContainer != null) {     fadeCandidate = true;     fadeContainer.setStyleClass("popupFadeReset");   }   //Only continue if we can actually fade this popup   if (fadeCandidate) {   //See if a delay has been specified     var waitTimeSeconds = event.getSource().getProperty('preFadeDelay');     //Default to 5 seconds if not supplied     if (waitTimeSeconds == undefined) {     waitTimeSeconds = 5;     }     // Now call the fade after the specified time     var fadeFunction = function () {     initiatePopupFade(fadePopup);     };     var fadeDelayTimer = setTimeout(fadeFunction, (waitTimeSeconds * 1000));   } } The things to note about this function is the initial check that we have to do to ensure that the container is currently visible and reset it's style to ensure that it is.  This is to handle the situation where the popup has begun the fade, and yet the user has still explicitly dismissed the popup before it's complete and in doing so has prevented the callback function (described later) from executing. In this particular situation the initial display of the dialog will be (apparently) missing it's normal animation but at least it becomes visible to the user (and most users will probably not notice this difference in any case). You'll notice that the style that we apply to reset the  opacity - popupFadeReset, is not applied to the popup component itself but rather the dialog or panelWindow within it. More about that in the description of the next function findFadeContainer(). Finally, assuming that we have a suitable candidate for fading, a JavaScript  timer is started using the specified preFadeDelay wait time (or 5 seconds if that was not supplied). When this timer expires then the main animation styleclass will be applied using the initiatePopupFade() function Function - findFadeContainer As a component, the <af:popup> does not support styleClass attribute, so we can't apply the animation style directly.  Instead we have to look for the container within the popup which defines the window object that can have a style attached.  This is achieved by the following code: /**  * The thing we actually fade will be the only child  * of the popup assuming that this is a dialog or window  * @param popup  * @return the component, or null if this is not valid for fading  */ function findFadeContainer(popup) { var children = popup.getDescendantComponents();   var fadeContainer = children[0];   if (fadeContainer != undefined) {   var compType = fadeContainer.getComponentType();     if (compType == "oracle.adf.RichPanelWindow" || compType == "oracle.adf.RichDialog") {     return fadeContainer;     }   }   return null; }  So what we do here is to grab the first child component of the popup and check its type. Here I decided to limit the fade behaviour to only <af:dialog> and <af:panelWindow>. This was deliberate.  If  we apply the fade to say an <af:noteWindow> you would see the text inside the balloon fade, but the balloon itself would hang around until the fade animation was over and then hide.  It would of course be possible to make the code smarter to walk up the DOM tree to find the correct <div> to apply the style to in order to hide the whole balloon, however, that means that this JavaScript would then need to have knowledge of the generated DOM structure, something which may change from release to release, and certainly something to avoid. So, all in all, I think that this is an OK restriction and frankly it's windows and dialogs that I wanted to fade anyway, not balloons and menus. You could of course extend this technique and handle the other types should you really want to. One thing to note here is the selection of the first (children[0]) child of the popup. It does not matter if there are non-visible children such as clientListener before the <af:dialog> or <af:panelWindow> within the popup, they are not included in this array, so picking the first element in this way seems to be fine, no matter what the underlying ordering is within the JSF source.  If you wanted a super-robust version of the code you might want to iterate through the children array of the popup to check for the right type, again it's up to you.  Function -  initiatePopupFade  On to the actual fading. This is actually very simple and at it's heart, just the application of the popupFadeAnimate style to the correct component and then registering a callback to execute once the fade is done. /**  * Function which will kick off the animation to fade the dialog and register  * a callback to correctly reset the popup once the animation is complete  * @param popup the popup we are animating  */ function initiatePopupFade(popup) { //Only continue if the popup has not already been dismissed    if (popup.isPopupVisible()) {   //The skin styles that define the animation      var fadeoutAnimationStyle = "popupFadeAnimate";     var fadeAnimationResetStyle = "popupFadeReset";     var fadeContainer = findFadeContainer(popup);     if (fadeContainer != null) {     var fadeContainerReal = AdfAgent.AGENT.getElementById(fadeContainer.getClientId());       //Define the callback this will correctly reset the popup once it's disappeared       var fadeCallbackFunction = function (event) {       closeFadedPopup(popup, fadeContainer, fadeAnimationResetStyle);         event.target.removeEventListener("webkitTransitionEnd", fadeCallbackFunction);       };       //Initiate the fade       fadeContainer.setStyleClass(fadeoutAnimationStyle);       //Register the callback to execute once fade is done       fadeContainerReal.addEventListener("webkitTransitionEnd", fadeCallbackFunction, false);     }   } } I've added some extra checks here though. First of all we only start the whole process if the popup is still visible. It may be that the user has closed the popup before the delay timer has finished so there is no need to start animating in that case. Again we use the findFadeContainer() function to locate the correct component to apply the style to, and additionally we grab the DOM id that represents that container.  This physical ID is required for the registration of the callback function. The closeFadedPopup() call is then registered on the callback so as to correctly close the now transparent (but still there) popup. Function -  closeFadedPopup The final function just cleans things up: /**  * Callback function to correctly cancel and reset the style in the popup  * @param popup id of the popup so we can close it properly  * @param contatiner the window / dialog within the popup to actually style  * @param resetStyle the syle that sets the opacity back to solid  */ function closeFadedPopup(popup, container, resetStyle) { container.setStyleClass(resetStyle);   popup.cancel(); }  First of all we reset the style to make the popup contents opaque again and then we cancel the popup.  This will ensure that any of your user code that is waiting for a popup cancelled event will actually get the event, additionally if you have done this as a modal window / dialog it will ensure that the glasspane is dismissed and you can interact with the UI again.  What's Next? There are several ways in which this technique could be used, I've been working on a popup here, but you could apply the same approach to in-line messages. As this code (in the popup case) is generic it will make s pretty nice declarative component and maybe, if I get time, I'll look at constructing a formal Growl component using a combination of this technique, and active data push. Also, I'm sure the above code can be improved a little too.  Specifically things like registering a popup cancelled listener to handle the style reset so that we don't loose the subtle animation that takes place when the popup is opened in that situation where the user has closed the in-fade dialog.

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  • Changes in licence in forked project what are my rights?

    - by Wes
    Hi I'm intrested in using the apparently now defunct app-mdi libray in a flex application for a paying customer. http://sourceforge.net/projects/appmdi/ It appears that the app-mdi project has been forked from flex-mdi and indeed the code has so much in common it would appear almost identical to the origional code. Now in the original source flex-mdi the following licence appears in the source code /* Copyright (c) 2007 FlexMDI Contributors. See: http://code.google.com/p/flexmdi/wiki/ProjectContributors Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ However in the app-mdi library on the same file the following licence appears. Copyright (c) 2010, TRUEAGILE All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. Neither the name of the TRUEAGILE nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ Now I've no problem with the licence except for the line. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. The copyright notice in its entireity makes no sense in binary material. Specifically talking about redistobutions in the binary form. Finally the question is what exactly has to be shown on web clients who access softare that utilises this library? Also is changing the licence in this manner actually allowed?

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  • Quick Quips on QR Codes

    - by Tim Dexter
    Yes, I'm an alliterating all-star; I missed my calling as a newspaper headline writer. I have recently received questions from several folks on support for QR codes. You know them they are everywhere you look, even here! How does Publisher handle QR codes then? In theory, exactly the same way we handle any other 2D barcode font. We need the font file, a mapping entry and an encoding class. With those three pieces we can embed QR codes into any output. To test the theory, I went off to IDAutomation, I have worked with them and many customers over the years and their fonts and encoders have worked great and have been very reliable. They kindly provide demo fonts which has made my life so much easier to be able to write posts like this. Their QR font and encoder is a little tough to find. I started here and then hit the Demo Now button. On the next page I hit the right hand Demo Now button. In the resulting zip file you'll need two files: AdditionalFonts.zip >> Automation2DFonts >> TrueType >> IDAutomation2D.ttf Java Class Encoder >> IDAutomation_JavaFontEncoder_QRCode.jar - the QRBarcodeExample.java is useful to see how to call the encoder. The font file needs to be installed into the windows/fonts directory, just copy and paste it in using file explorer and windows will install it for you. Remember, we are using the demo font here and you'll see if you get your phones decoder to looks a the font above there is a fixed string 'DEMO' at the beginning. You want that removed? Go buy the font from the IDAutomation folks. The Encoder Next you need to create your encoding wrapper class. Publisher does ship a class but its compiled and I do not recommend trying to modify it, you can just build your own. I have loaded up my class here. You do not need to be a java guru, its pretty straightforward. I'd recommend a java IDE like JDeveloper from a convenience point of view. I have annotated my class and added a main method to it so you can test your encoders from JDeveloper without having to deploy them first. You can load up the project form the zip file straight into JDeveloper.Next, take a look at IDAutomation's example java class and you'll see: QRCodeEncoder qre=new QRCodeEncoder();  String DataToEncode = "IDAutmation Inc.";  boolean ApplyTilde = false;  int EncodingMode = 0;  int Version = 0;  int ErrorCorrectionLevel = 0;  System.out.println( qre.FontEncode(DataToEncode, ApplyTilde, EncodingMode, Version, ErrorCorrectionLevel) ); You'll need to check what settings you need to set for the ApplyTilde, EncodingMode, Version and ErrorCorrectionLevel. They are covered in the user guide from IDAutomation here. If you do not want to hard code the values in the encoder then you can quite easily externalize them and read the values from a text file. I have not covered that scenario here, I'm going with IDAutomation's defaults and my phone app is reading the fonts no problem. Now you know how to call the encoder, you need to incorporate it into your encoder wrapper class. From my sample class:       Class[] clazz = new Class[] { "".getClass() };        ENCODERS.put("code128a",mUtility.getClass().getMethod("code128a", clazz));       ENCODERS.put("code128b",mUtility.getClass().getMethod("code128b", clazz));       ENCODERS.put("code128c",mUtility.getClass().getMethod("code128c", clazz));       ENCODERS.put("qrcode",mUtility.getClass().getMethod("qrcode", clazz)); I just added a new entry to register the encoder method 'qrcode' (in red). Then I created a new method inside the class to call the IDAutomation encoder. /** Call to IDAutomations QR Code encoder. Passing the data to encode      Returning the encoded string to the template for formatting **/ public static final String qrcode (String DataToEncode) {   QRCodeEncoder qre=new QRCodeEncoder();    boolean ApplyTilde = false;    int EncodingMode = 0;    int Version = 0;    int ErrorCorrectionLevel = 0; return qre.FontEncode(DataToEncode, ApplyTilde, EncodingMode, Version, ErrorCorrectionLevel); } Almost the exact same code in their sample class. The DataToEncode string is passed in rather than hardcoded of course. With the class done you can now compile it, but you need to ensure that the IDAutomation_JavaFontEncoder_QRCode.jar is in the classpath. In JDeveloper, open the project properties >> Libraries and Classpaths and then add the jar to the list. You'll need the publisher jars too. You can find those in the jlib directory in your Template Builder for Word directory.Note! In my class, I have used package oracle.psbi.barcode; As my package spec, yours will be different but you need to note it for later. Once you have it compiling without errors you will need to generate a jar file to keep it in. In JDeveloper highlight your project node >> New >> Deployment Profile >> JAR file. Once you have created the descriptor, just take the defaults. It will tell you where the jar is located. Go get it and then its time to copy it and the IDAutomation jar into the Template Builder for Word directory structure. Deploying the jars On your windows machine locate the jlib directory under the Template Builder for Word install directory. On my machine its here, F:\Program Files\Oracle\BI Publisher\BI Publisher Desktop\Template Builder for Word\jlib. Copy both of the jar files into the directory. The next step is to get the jars into the classpath for the Word plugin so that Publisher can find your wrapper class and it can then find the IDAutomation encoder. The most consistent way I have found so far, is to open up the RTF2PDF.jar in the same directory and make some mods. First make a backup of the jar file then open it using winzip or 7zip or similar and get into the META-INF directory. In there is a file, MANIFEST.MF. This contains the classpath for the plugin, open it in an editor and add the jars to the end of the classpath list. In mine I have: Manifest-Version: 1.0 Class-Path: ./activation.jar ./mail.jar ./xdochartstyles.jar ./bicmn.jar ./jewt4.jar ./share.jar ./bipres.jar ./xdoparser.jar ./xdocore.jar ./xmlparserv2.jar ./xmlparserv2-904.jar  ./i18nAPI_v3.jar ./versioninfo.jar ./barcodejar.jar ./IDAutomation_JavaFontEncoder_QRCode.jar Main-Class: RTF2PDF I have put in carriage returns above to make the Class-Path: entry more readable, make sure yours is all on one line. Be sure to use the ./ as a prefix to the jar name. Ensure the file is saved inside the jar file 7zip and winzip both have popups asking if you want to update the file in the jar file.Now you have the jars on the classpath, the Publisher plugin will be able to find our classes at run time. Referencing the Font The next step is to reference the font location so that the rendering engine can find it and embed a subset into the PDF output. Remember the other output formats rely on the font being present on the machine that is opening the document. The PDF is the only truly portable format. Inside the config directory under the Template Builder for Word install directory, mine is here, F:\Program Files\Oracle\BI Publisher\BI Publisher Desktop\Template Builder for Word\config. You'll find the file, 'xdo example.cfg'. Rename it to xdo.cfg and open it in a text editor. In the fonts section, create a new entry:       <font family="IDAutomation2D" style="normal" weight="normal">              <truetype path="C:\windows\fonts\IDAutomation2D.ttf" />       </font> Note, 'IDAutomation2D' (in red) is the same name as you can see when you open MSWord and look for the QRCode font. This must match exactly. When Publisher looks at the fonts in the RTF template at runtime it will see 'IDAutomation2D' it will then look at its font mapping entries to find where that font file resides on the disk. If the names do not match or the font is not present then the font will not get used and it will fall back on Helvetica. Building the Template Now you have the data encoder and the font in place and mapped; you can use it in the template. The two commands you will need to have present are: <?register-barcode-vendor:'ENCODER WRAPPER CLASS'; 'ENCODER NAME'?> for my encoder I have: <?register-barcode-vendor:'oracle.psbi.barcode.BarcodeUtil'; 'MyBarcodeEncoder'?> Notice the two parameters for the command. The first provides the package 'path' and class name (remember I said you need to remember that above.)The second is the name of the encoder, in my case 'MyBarcodeEncoder'. Check my full encoder class in the zip linked below to see where I named it. You can change it to something else, no problem.This command needs to be near the top of the template. The second command is the encoding command: <?format-barcode:DATAT_TO_ENCODE;'ENCODER_METHOD_NAME';'ENCODER_NAME'?> for my command I have <?format-barcode:DATATEXT;'qrcode';'MyBarcodeEncoder'?>DATATEXT is the XML element that contains the text to be encoded. If you want to hard code a piece of text just surround it with single quotes. qrcode is the name of my encoder method that calls the IDAutomation encoder. Remember this.MyBarcodeEncoder is the name of my encoder. Repetition? Yes but its needed again. Both of these commands are put inside their own form fields. Do not apply the QRCode font to the second field just yet. Lets make sure the encoder is working. Run you template with some data and you should get something like this for your encoded data: AHEEEHAPPJOPMOFADIPFJKDCLPAHEEEHA BNFFFNBPJGMDIDJPFOJGIGBLMPBNFFFNB APIBOHFJCFBNKHGGBMPFJFJLJBKGOMNII OANKPJFFLEPLDNPCLMNGNIJIHFDNLJFEH FPLFLHFHFILKFBLOIGMDFCFLGJGOPJJME CPIACDFJPBGDODOJCHALJOBPECKMOEDDF MFFNFNEPKKKCHAIHCHPCFFLDAHFHAGLMK APBBBPAPLDKNKJKKGIPDLKGMGHDDEPHLN HHHHHHHPHPHHPHPPHPPPPHHPHHPHPHPHP Grooovy huh? If you do not get the encoded text then go back and check that your jars are in the right spot and that you have the MANIFEST.MF file updated correctly. Once you do get the encoded text, highlight the field and apply the IDAutomation2D font to it. Then re-run the report and you will hopefully see the QR code in your output. If not, go back and check the xdo.cfg entry and make sure its in the right place and the font location is correct. That's it, you now have QR codes in Publisher outputs. Everything I have written above, has been tested with the 5.6.3, 10.1.3.4.2 codelines. I'll be testing the 11g code in the next day or two and will update you with any changes. One thing I have not covered yet and will do in the next few days is how to deploy all of this to your server. Look out for a follow up post. One note on the apparent white lines in the font (see the image above). Once printed they disappear and even viewing the code on a screen with the white lines, my phone app is still able to read and interpret the contents no problem. I have zipped up my encoder wrapper class as a JDeveloper 11.1.1.6 project here. Just dig into the src directories to find the BarcodeUtil.java file if you just want the code. I have put comments into the file to hopefully help the novice java programmer out. Happy QR'ing!

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  • Get XML from Server for Use on Windows Phone

    - by psheriff
    When working with mobile devices you always need to take into account bandwidth usage and power consumption. If you are constantly connecting to a server to retrieve data for an input screen, then you might think about moving some of that data down to the phone and cache the data on the phone. An example would be a static list of US State Codes that you are asking the user to select from. Since this is data that does not change very often, this is one set of data that would be great to cache on the phone. Since the Windows Phone does not have an embedded database, you can just use an XML string stored in Isolated Storage. Of course, then you need to figure out how to get data down to the phone. You can either ship it with the application, or connect and retrieve the data from your server one time and thereafter cache it and retrieve it from the cache. In this blog post you will see how to create a WCF service to retrieve data from a Product table in a database and send that data as XML to the phone and store it in Isolated Storage. You will then read that data from Isolated Storage using LINQ to XML and display it in a ListBox. Step 1: Create a Windows Phone Application The first step is to create a Windows Phone application called WP_GetXmlFromDataSet (or whatever you want to call it). On the MainPage.xaml add the following XAML within the “ContentPanel” grid: <StackPanel>  <Button Name="btnGetXml"          Content="Get XML"          Click="btnGetXml_Click" />  <Button Name="btnRead"          Content="Read XML"          IsEnabled="False"          Click="btnRead_Click" />  <ListBox Name="lstData"            Height="430"            ItemsSource="{Binding}"            DisplayMemberPath="ProductName" /></StackPanel> Now it is time to create the WCF Service Application that you will call to get the XML from a table in a SQL Server database. Step 2: Create a WCF Service Application Add a new project to your solution called WP_GetXmlFromDataSet.Services. Delete the IService1.* and Service1.* files and the App_Data folder, as you don’t generally need these items. Add a new WCF Service class called ProductService. In the IProductService class modify the void DoWork() method with the following code: [OperationContract]string GetProductXml(); Open the code behind in the ProductService.svc and create the GetProductXml() method. This method (shown below) will connect up to a database and retrieve data from a Product table. public string GetProductXml(){  string ret = string.Empty;  string sql = string.Empty;  SqlDataAdapter da;  DataSet ds = new DataSet();   sql = "SELECT ProductId, ProductName,";  sql += " IntroductionDate, Price";  sql += " FROM Product";   da = new SqlDataAdapter(sql,    ConfigurationManager.ConnectionStrings["Sandbox"].ConnectionString);   da.Fill(ds);   // Create Attribute based XML  foreach (DataColumn col in ds.Tables[0].Columns)  {    col.ColumnMapping = MappingType.Attribute;  }   ds.DataSetName = "Products";  ds.Tables[0].TableName = "Product";  ret = ds.GetXml();   return ret;} After retrieving the data from the Product table using a DataSet, you will want to set each column’s ColumnMapping property to Attribute. Using attribute based XML will make the data transferred across the wire a little smaller. You then set the DataSetName property to the top-level element name you want to assign to the XML. You then set the TableName property on the DataTable to the name you want each element to be in your XML. The last thing you need to do is to call the GetXml() method on the DataSet object which will return an XML string of the data in your DataSet object. This is the value that you will return from the service call. The XML that is returned from the above call looks like the following: <Products>  <Product ProductId="1"           ProductName="PDSA .NET Productivity Framework"           IntroductionDate="9/3/2010"           Price="5000" />  <Product ProductId="3"           ProductName="Haystack Code Generator for .NET"           IntroductionDate="7/1/2010"           Price="599.00" />  ...  ...  ... </Products> The GetProductXml() method uses a connection string from the Web.Config file, so add a <connectionStrings> element to the Web.Config file in your WCF Service application. Modify the settings shown below as needed for your server and database name. <connectionStrings>  <add name="Sandbox"        connectionString="Server=Localhost;Database=Sandbox;                         Integrated Security=Yes"/></connectionStrings> The Product Table You will need a Product table that you can read data from. I used the following structure for my product table. Add any data you want to this table after you create it in your database. CREATE TABLE Product(  ProductId int PRIMARY KEY IDENTITY(1,1) NOT NULL,  ProductName varchar(50) NOT NULL,  IntroductionDate datetime NULL,  Price money NULL) Step 3: Connect to WCF Service from Windows Phone Application Back in your Windows Phone application you will now need to add a Service Reference to the WCF Service application you just created. Right-mouse click on the Windows Phone Project and choose Add Service Reference… from the context menu. Click on the Discover button. In the Namespace text box enter “ProductServiceRefrence”, then click the OK button. If you entered everything correctly, Visual Studio will generate some code that allows you to connect to your Product service. On the MainPage.xaml designer window double click on the Get XML button to generate the Click event procedure for this button. In the Click event procedure make a call to a GetXmlFromServer() method. This method will also need a “Completed” event procedure to be written since all communication with a WCF Service from Windows Phone must be asynchronous.  Write these two methods as follows: private const string KEY_NAME = "ProductData"; private void GetXmlFromServer(){  ProductServiceClient client = new ProductServiceClient();   client.GetProductXmlCompleted += new     EventHandler<GetProductXmlCompletedEventArgs>      (client_GetProductXmlCompleted);   client.GetProductXmlAsync();  client.CloseAsync();} void client_GetProductXmlCompleted(object sender,                                   GetProductXmlCompletedEventArgs e){  // Store XML data in Isolated Storage  IsolatedStorageSettings.ApplicationSettings[KEY_NAME] = e.Result;   btnRead.IsEnabled = true;} As you can see, this is a fairly standard call to a WCF Service. In the Completed event you get the Result from the event argument, which is the XML, and store it into Isolated Storage using the IsolatedStorageSettings.ApplicationSettings class. Notice the constant that I added to specify the name of the key. You will use this constant later to read the data from Isolated Storage. Step 4: Create a Product Class Even though you stored XML data into Isolated Storage when you read that data out you will want to convert each element in the XML file into an actual Product object. This means that you need to create a Product class in your Windows Phone application. Add a Product class to your project that looks like the code below: public class Product{  public string ProductName{ get; set; }  public int ProductId{ get; set; }  public DateTime IntroductionDate{ get; set; }  public decimal Price{ get; set; }} Step 5: Read Settings from Isolated Storage Now that you have the XML data stored in Isolated Storage, it is time to use it. Go back to the MainPage.xaml design view and double click on the Read XML button to generate the Click event procedure. From the Click event procedure call a method named ReadProductXml().Create this method as shown below: private void ReadProductXml(){  XElement xElem = null;   if (IsolatedStorageSettings.ApplicationSettings.Contains(KEY_NAME))  {    xElem = XElement.Parse(     IsolatedStorageSettings.ApplicationSettings[KEY_NAME].ToString());     // Create a list of Product objects    var products =         from prod in xElem.Descendants("Product")        orderby prod.Attribute("ProductName").Value        select new Product        {          ProductId = Convert.ToInt32(prod.Attribute("ProductId").Value),          ProductName = prod.Attribute("ProductName").Value,          IntroductionDate =             Convert.ToDateTime(prod.Attribute("IntroductionDate").Value),          Price = Convert.ToDecimal(prod.Attribute("Price").Value)        };     lstData.DataContext = products;  }} The ReadProductXml() method checks to make sure that the key name that you saved your XML as exists in Isolated Storage prior to trying to open it. If the key name exists, then you retrieve the value as a string. Use the XElement’s Parse method to convert the XML string to a XElement object. LINQ to XML is used to iterate over each element in the XElement object and create a new Product object from each attribute in your XML file. The LINQ to XML code also orders the XML data by the ProductName. After the LINQ to XML code runs you end up with an IEnumerable collection of Product objects in the variable named “products”. You assign this collection of product data to the DataContext of the ListBox you created in XAML. The DisplayMemberPath property of the ListBox is set to “ProductName” so it will now display the product name for each row in your products collection. Summary In this article you learned how to retrieve an XML string from a table in a database, return that string across a WCF Service and store it into Isolated Storage on your Windows Phone. You then used LINQ to XML to create a collection of Product objects from the data stored and display that data in a Windows Phone list box. This same technique can be used in Silverlight or WPF applications too. NOTE: You can download the complete sample code at my website. http://www.pdsa.com/downloads. Choose Tips & Tricks, then "Get XML From Server for Use on Windows Phone" from the drop-down. Good Luck with your Coding,Paul Sheriff ** SPECIAL OFFER FOR MY BLOG READERS **Visit http://www.pdsa.com/Event/Blog for a free video on Silverlight entitled Silverlight XAML for the Complete Novice - Part 1.  

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  • Why should main() be short?

    - by Stargazer712
    I've been programming for over 9 years, and according to the advice of my first programming teacher, I always keep my main() function extremely short. At first I had no idea why. I just obeyed without understanding, much to the delight of my professors. After gaining experience, I realized that if I designed my code correctly, having a short main() function just sortof happened. Writing modularized code and following the single responsibility principle allowed my code to be designed in "bunches", and main() served as nothing more than a catalyst to get the program running. Fast forward to a few weeks ago, I was looking at Python's souce code, and I found the main() function: /* Minimal main program -- everything is loaded from the library */ ... int main(int argc, char **argv) { ... return Py_Main(argc, argv); } Yay Python. Short main() function == Good code. Programming teachers were right. Wanting to look deeper, I took a look at Py_Main. In its entirety, it is defined as follows: /* Main program */ int Py_Main(int argc, char **argv) { int c; int sts; char *command = NULL; char *filename = NULL; char *module = NULL; FILE *fp = stdin; char *p; int unbuffered = 0; int skipfirstline = 0; int stdin_is_interactive = 0; int help = 0; int version = 0; int saw_unbuffered_flag = 0; PyCompilerFlags cf; cf.cf_flags = 0; orig_argc = argc; /* For Py_GetArgcArgv() */ orig_argv = argv; #ifdef RISCOS Py_RISCOSWimpFlag = 0; #endif PySys_ResetWarnOptions(); while ((c = _PyOS_GetOpt(argc, argv, PROGRAM_OPTS)) != EOF) { if (c == 'c') { /* -c is the last option; following arguments that look like options are left for the command to interpret. */ command = (char *)malloc(strlen(_PyOS_optarg) + 2); if (command == NULL) Py_FatalError( "not enough memory to copy -c argument"); strcpy(command, _PyOS_optarg); strcat(command, "\n"); break; } if (c == 'm') { /* -m is the last option; following arguments that look like options are left for the module to interpret. */ module = (char *)malloc(strlen(_PyOS_optarg) + 2); if (module == NULL) Py_FatalError( "not enough memory to copy -m argument"); strcpy(module, _PyOS_optarg); break; } switch (c) { case 'b': Py_BytesWarningFlag++; break; case 'd': Py_DebugFlag++; break; case '3': Py_Py3kWarningFlag++; if (!Py_DivisionWarningFlag) Py_DivisionWarningFlag = 1; break; case 'Q': if (strcmp(_PyOS_optarg, "old") == 0) { Py_DivisionWarningFlag = 0; break; } if (strcmp(_PyOS_optarg, "warn") == 0) { Py_DivisionWarningFlag = 1; break; } if (strcmp(_PyOS_optarg, "warnall") == 0) { Py_DivisionWarningFlag = 2; break; } if (strcmp(_PyOS_optarg, "new") == 0) { /* This only affects __main__ */ cf.cf_flags |= CO_FUTURE_DIVISION; /* And this tells the eval loop to treat BINARY_DIVIDE as BINARY_TRUE_DIVIDE */ _Py_QnewFlag = 1; break; } fprintf(stderr, "-Q option should be `-Qold', " "`-Qwarn', `-Qwarnall', or `-Qnew' only\n"); return usage(2, argv[0]); /* NOTREACHED */ case 'i': Py_InspectFlag++; Py_InteractiveFlag++; break; /* case 'J': reserved for Jython */ case 'O': Py_OptimizeFlag++; break; case 'B': Py_DontWriteBytecodeFlag++; break; case 's': Py_NoUserSiteDirectory++; break; case 'S': Py_NoSiteFlag++; break; case 'E': Py_IgnoreEnvironmentFlag++; break; case 't': Py_TabcheckFlag++; break; case 'u': unbuffered++; saw_unbuffered_flag = 1; break; case 'v': Py_VerboseFlag++; break; #ifdef RISCOS case 'w': Py_RISCOSWimpFlag = 1; break; #endif case 'x': skipfirstline = 1; break; /* case 'X': reserved for implementation-specific arguments */ case 'U': Py_UnicodeFlag++; break; case 'h': case '?': help++; break; case 'V': version++; break; case 'W': PySys_AddWarnOption(_PyOS_optarg); break; /* This space reserved for other options */ default: return usage(2, argv[0]); /*NOTREACHED*/ } } if (help) return usage(0, argv[0]); if (version) { fprintf(stderr, "Python %s\n", PY_VERSION); return 0; } if (Py_Py3kWarningFlag && !Py_TabcheckFlag) /* -3 implies -t (but not -tt) */ Py_TabcheckFlag = 1; if (!Py_InspectFlag && (p = Py_GETENV("PYTHONINSPECT")) && *p != '\0') Py_InspectFlag = 1; if (!saw_unbuffered_flag && (p = Py_GETENV("PYTHONUNBUFFERED")) && *p != '\0') unbuffered = 1; if (!Py_NoUserSiteDirectory && (p = Py_GETENV("PYTHONNOUSERSITE")) && *p != '\0') Py_NoUserSiteDirectory = 1; if ((p = Py_GETENV("PYTHONWARNINGS")) && *p != '\0') { char *buf, *warning; buf = (char *)malloc(strlen(p) + 1); if (buf == NULL) Py_FatalError( "not enough memory to copy PYTHONWARNINGS"); strcpy(buf, p); for (warning = strtok(buf, ","); warning != NULL; warning = strtok(NULL, ",")) PySys_AddWarnOption(warning); free(buf); } if (command == NULL && module == NULL && _PyOS_optind < argc && strcmp(argv[_PyOS_optind], "-") != 0) { #ifdef __VMS filename = decc$translate_vms(argv[_PyOS_optind]); if (filename == (char *)0 || filename == (char *)-1) filename = argv[_PyOS_optind]; #else filename = argv[_PyOS_optind]; #endif } stdin_is_interactive = Py_FdIsInteractive(stdin, (char *)0); if (unbuffered) { #if defined(MS_WINDOWS) || defined(__CYGWIN__) _setmode(fileno(stdin), O_BINARY); _setmode(fileno(stdout), O_BINARY); #endif #ifdef HAVE_SETVBUF setvbuf(stdin, (char *)NULL, _IONBF, BUFSIZ); setvbuf(stdout, (char *)NULL, _IONBF, BUFSIZ); setvbuf(stderr, (char *)NULL, _IONBF, BUFSIZ); #else /* !HAVE_SETVBUF */ setbuf(stdin, (char *)NULL); setbuf(stdout, (char *)NULL); setbuf(stderr, (char *)NULL); #endif /* !HAVE_SETVBUF */ } else if (Py_InteractiveFlag) { #ifdef MS_WINDOWS /* Doesn't have to have line-buffered -- use unbuffered */ /* Any set[v]buf(stdin, ...) screws up Tkinter :-( */ setvbuf(stdout, (char *)NULL, _IONBF, BUFSIZ); #else /* !MS_WINDOWS */ #ifdef HAVE_SETVBUF setvbuf(stdin, (char *)NULL, _IOLBF, BUFSIZ); setvbuf(stdout, (char *)NULL, _IOLBF, BUFSIZ); #endif /* HAVE_SETVBUF */ #endif /* !MS_WINDOWS */ /* Leave stderr alone - it should be unbuffered anyway. */ } #ifdef __VMS else { setvbuf (stdout, (char *)NULL, _IOLBF, BUFSIZ); } #endif /* __VMS */ #ifdef __APPLE__ /* On MacOS X, when the Python interpreter is embedded in an application bundle, it gets executed by a bootstrapping script that does os.execve() with an argv[0] that's different from the actual Python executable. This is needed to keep the Finder happy, or rather, to work around Apple's overly strict requirements of the process name. However, we still need a usable sys.executable, so the actual executable path is passed in an environment variable. See Lib/plat-mac/bundlebuiler.py for details about the bootstrap script. */ if ((p = Py_GETENV("PYTHONEXECUTABLE")) && *p != '\0') Py_SetProgramName(p); else Py_SetProgramName(argv[0]); #else Py_SetProgramName(argv[0]); #endif Py_Initialize(); if (Py_VerboseFlag || (command == NULL && filename == NULL && module == NULL && stdin_is_interactive)) { fprintf(stderr, "Python %s on %s\n", Py_GetVersion(), Py_GetPlatform()); if (!Py_NoSiteFlag) fprintf(stderr, "%s\n", COPYRIGHT); } if (command != NULL) { /* Backup _PyOS_optind and force sys.argv[0] = '-c' */ _PyOS_optind--; argv[_PyOS_optind] = "-c"; } if (module != NULL) { /* Backup _PyOS_optind and force sys.argv[0] = '-c' so that PySys_SetArgv correctly sets sys.path[0] to '' rather than looking for a file called "-m". See tracker issue #8202 for details. */ _PyOS_optind--; argv[_PyOS_optind] = "-c"; } PySys_SetArgv(argc-_PyOS_optind, argv+_PyOS_optind); if ((Py_InspectFlag || (command == NULL && filename == NULL && module == NULL)) && isatty(fileno(stdin))) { PyObject *v; v = PyImport_ImportModule("readline"); if (v == NULL) PyErr_Clear(); else Py_DECREF(v); } if (command) { sts = PyRun_SimpleStringFlags(command, &cf) != 0; free(command); } else if (module) { sts = RunModule(module, 1); free(module); } else { if (filename == NULL && stdin_is_interactive) { Py_InspectFlag = 0; /* do exit on SystemExit */ RunStartupFile(&cf); } /* XXX */ sts = -1; /* keep track of whether we've already run __main__ */ if (filename != NULL) { sts = RunMainFromImporter(filename); } if (sts==-1 && filename!=NULL) { if ((fp = fopen(filename, "r")) == NULL) { fprintf(stderr, "%s: can't open file '%s': [Errno %d] %s\n", argv[0], filename, errno, strerror(errno)); return 2; } else if (skipfirstline) { int ch; /* Push back first newline so line numbers remain the same */ while ((ch = getc(fp)) != EOF) { if (ch == '\n') { (void)ungetc(ch, fp); break; } } } { /* XXX: does this work on Win/Win64? (see posix_fstat) */ struct stat sb; if (fstat(fileno(fp), &sb) == 0 && S_ISDIR(sb.st_mode)) { fprintf(stderr, "%s: '%s' is a directory, cannot continue\n", argv[0], filename); fclose(fp); return 1; } } } if (sts==-1) { /* call pending calls like signal handlers (SIGINT) */ if (Py_MakePendingCalls() == -1) { PyErr_Print(); sts = 1; } else { sts = PyRun_AnyFileExFlags( fp, filename == NULL ? "<stdin>" : filename, filename != NULL, &cf) != 0; } } } /* Check this environment variable at the end, to give programs the * opportunity to set it from Python. */ if (!Py_InspectFlag && (p = Py_GETENV("PYTHONINSPECT")) && *p != '\0') { Py_InspectFlag = 1; } if (Py_InspectFlag && stdin_is_interactive && (filename != NULL || command != NULL || module != NULL)) { Py_InspectFlag = 0; /* XXX */ sts = PyRun_AnyFileFlags(stdin, "<stdin>", &cf) != 0; } Py_Finalize(); #ifdef RISCOS if (Py_RISCOSWimpFlag) fprintf(stderr, "\x0cq\x0c"); /* make frontend quit */ #endif #ifdef __INSURE__ /* Insure++ is a memory analysis tool that aids in discovering * memory leaks and other memory problems. On Python exit, the * interned string dictionary is flagged as being in use at exit * (which it is). Under normal circumstances, this is fine because * the memory will be automatically reclaimed by the system. Under * memory debugging, it's a huge source of useless noise, so we * trade off slower shutdown for less distraction in the memory * reports. -baw */ _Py_ReleaseInternedStrings(); #endif /* __INSURE__ */ return sts; } Good God Almighty...it is big enough to sink the Titanic. It seems as though Python did the "Intro to Programming 101" trick and just moved all of main()'s code to a different function called it something very similar to "main". Here's my question: Is this code terribly written, or are there other reasons reasons to have a short main function? As it stands right now, I see absolutely no difference between doing this and just moving the code in Py_Main() back into main(). Am I wrong in thinking this?

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  • Silverlight Cream for December 07, 2010 -- #1004

    - by Dave Campbell
    In this Issue: András Velvárt, Kunal Chowdhury(-2-), AvraShow, Gill Cleeren, Ian T. Lackey, Richard Waddell, Joe McBride, Michael Crump, Xpert360, keyboardP, and Pete Vickers(-2-). Above the Fold: Silverlight: "Grouping Records in Silverlight DataGrid using PagedCollectionView" Kunal Chowdhury WP7: "Phone 7 Back Button and the ListPicker control" Ian T. Lackey Shoutouts: Colin Eberhardt has some Silverlight 5 Adoption Predictions you may want to check out. Michael Crump has a post up showing lots of the goodness of Silverlight 5 from the Firestarter... screenshots, code snippets, etc: Silverlight 5 – What’s New? (Including Screenshots & Code Snippets) Kunal Chowdhury has a pretty complete Silverlight 5 feature set from the Firestarter and an embedded copy of Scott Guthrie's kenote running on the page: New Features Announced for Silverlight 5 Beta From SilverlightCream.com: Just how productive is WP7 development compared to iOS, Android and mobile Web? András Velvárt blogged about a contest he took part in to build a WP7 app in 1-1/2 hours without any prior knowledge of it's funtion. He and his team-mate were pitted against other teams on Android, IOS, and mobile Web... guess who got (almost) their entire app running? ... just too cool Andras! ... Grouping Records in Silverlight DataGrid using PagedCollectionView Kunal Chowdhury has a couple good posts up, this first one is on using the PagedCollectionView to group the records in a DataGrid... code included. Filtering Records in Silverlight DataGrid using PagedCollectionView Kunal Chowdhury then continues with another post on the PagedCollectionView only this time is showing how to do some filtering. DeepZoom Tips and Techniques AvraShow has a post up discussing using DeepZoom to explore, in his case, a Printed Circuit Board, with information about how he proceeded in doing that, and some tips and techniques along the way. The validation story in Silverlight (Part 2) Gill Cleeren has Part 2 of his Silverlight Validation series up at SilverlightShow. This post gets into IDataErrorInfo and INotifyDataErrorInfo. Lots of code and the example is available for download. Phone 7 Back Button and the ListPicker control Ian T. Lackey has a post up about the WP7 backbutton and what can get a failure from the Marketplace in that area, and how that applies to the ListPicker as well. Very Simple Example of ICommand CanExecute Method and CanExecuteChanged Event Richard Waddell has a nice detailed tutorial on ICommand and dealing with CanExecute... lots of Blend love in this post. Providing an Alternating Background Color for an ItemsControl Joe McBride has a post up discussing putting an alternating background color on an ItemsControl... you know, how you do on a grid... interesting idea, and all the code... Pimp my Silverlight Firestarter Michael Crump has a great Firestarter post up ... where and how to get the videos, the labs... a good Firestarter resource for sure. Adventures with PivotViewer Part 7: Slider control Xpert360 has part 7 of the PivotViewer series they're doing up. This time they're demonstrating taking programmatic control of the Zoom slider. Creating Transparent Lockscreen Wallpapers for WP7 I don't know keyboardP's name, but he's got a cool post up about getting an image up for the WP7 lock screen that has transparent regions on it... pretty cool actually. Windows Phone 7 Linq to XML 'strangeness' Pete Vickers has a post up describing a problem he found with Linq to XML on WP7. He even has a demo app that has the problem, and the fix... and it's all downloadable. Windows Phone 7 multi-line radio buttons Pete Vickers has another quick post up on radio buttons with so much text that it needs wrapping ... this is for WP7, but applies to Silverlight in general. Stay in the 'Light! Twitter SilverlightNews | Twitter WynApse | WynApse.com | Tagged Posts | SilverlightCream Join me @ SilverlightCream | Phoenix Silverlight User Group Technorati Tags: Silverlight    Silverlight 3    Silverlight 4    Windows Phone MIX10

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  • How do you educate your teammates without seeming condescending or superior?

    - by Dan Tao
    I work with three other guys; I'll call them Adam, Brian, and Chris. Adam and Brian are bright guys. Give them a problem; they will figure out a way to solve it. When it comes to OOP, though, they know very little about it and aren't particularly interested in learning. Pure procedural code is their MO. Chris, on the other hand, is an OOP guy all the way -- and a cocky, condescending one at that. He is constantly criticizing the work Adam and Brian do and talking to me as if I must share his disdain for the two of them. When I say that Adam and Brian aren't interested in learning about OOP, I suspect Chris is the primary reason. This hasn't bothered me too much for the most part, but there have been times when, looking at some code Adam or Brian wrote, it has pained me to think about how a problem could have been solved so simply using inheritance or some other OOP concept instead of the unmaintainable mess of 1,000 lines of code that ended up being written instead. And now that the company is starting a rather ambitious new project, with Adam assigned to the task of getting the core functionality in place, I fear the result. Really, I just want to help these guys out. But I know that if I come across as just another holier-than-thou developer like Chris, it's going to be massively counterproductive. I've considered: Team code reviews -- everybody reviews everybody's code. This way no one person is really in a position to look down on anyone else; besides, I know I could learn plenty from the other members on the team as well. But this would be time-consuming, and with such a small team, I have trouble picturing it gaining much traction as a team practice. Periodic e-mails to the team -- this would entail me sending out an e-mail every now and then discussing some concept that, based on my observation, at least one team member would benefit from learning about. The downside to this approach is I do think it could easily make me come across as a self-appointed expert. Keeping a blog -- I already do this, actually; but so far my blog has been more about esoteric little programming tidbits than straightforward practical advice. And anyway, I suspect it would get old pretty fast if I were constantly telling my coworkers, "Hey guys, remember to check out my new blog post!" This question doesn't need to be specifically about OOP or any particular programming paradigm or technology. I just want to know: how have you found success in teaching new concepts to your coworkers without seeming like a condescending know-it-all? It's pretty clear to me there isn't going to be a sure-fire answer, but any helpful advice (including methods that have worked as well as those that have proved ineffective or even backfired) would be greatly appreciated. UPDATE: I am not the Team Lead on this team. Chris is. UPDATE 2: Made community wiki to accord with the general sentiment of the community (fancy that).

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  • Detecting HTML5/CSS3 Features using Modernizr

    - by dwahlin
    HTML5, CSS3, and related technologies such as canvas and web sockets bring a lot of useful new features to the table that can take Web applications to the next level. These new technologies allow applications to be built using only HTML, CSS, and JavaScript allowing them to be viewed on a variety of form factors including tablets and phones. Although HTML5 features offer a lot of promise, it’s not realistic to develop applications using the latest technologies without worrying about supporting older browsers in the process. If history has taught us anything it’s that old browsers stick around for years and years which means developers have to deal with backward compatibility issues. This is especially true when deploying applications to the Internet that target the general public. This begs the question, “How do you move forward with HTML5 and CSS3 technologies while gracefully handling unsupported features in older browsers?” Although you can write code by hand to detect different HTML5 and CSS3 features, it’s not always straightforward. For example, to check for canvas support you need to write code similar to the following:   <script> window.onload = function () { if (canvasSupported()) { alert('canvas supported'); } }; function canvasSupported() { var canvas = document.createElement('canvas'); return (canvas.getContext && canvas.getContext('2d')); } </script> If you want to check for local storage support the following check can be made. It’s more involved than it should be due to a bug in older versions of Firefox. <script> window.onload = function () { if (localStorageSupported()) { alert('local storage supported'); } }; function localStorageSupported() { try { return ('localStorage' in window && window['localStorage'] != null); } catch(e) {} return false; } </script> Looking through the previous examples you can see that there’s more than meets the eye when it comes to checking browsers for HTML5 and CSS3 features. It takes a lot of work to test every possible scenario and every version of a given browser. Fortunately, you don’t have to resort to writing custom code to test what HTML5/CSS3 features a given browser supports. By using a script library called Modernizr you can add checks for different HTML5/CSS3 features into your pages with a minimal amount of code on your part. Let’s take a look at some of the key features Modernizr offers.   Getting Started with Modernizr The first time I heard the name “Modernizr” I thought it “modernized” older browsers by added missing functionality. In reality, Modernizr doesn’t actually handle adding missing features or “modernizing” older browsers. The Modernizr website states, “The name Modernizr actually stems from the goal of modernizing our development practices (and ourselves)”. Because it relies on feature detection rather than browser sniffing (a common technique used in the past – that never worked that great), Modernizr definitely provides a more modern way to test features that a browser supports and can even handle loading additional scripts called shims or polyfills that fill in holes that older browsers may have. It’s a great tool to have in your arsenal if you’re a web developer. Modernizr is available at http://modernizr.com. Two different types of scripts are available including a development script and custom production script. To generate a production script, the site provides a custom script generation tool rather than providing a single script that has everything under the sun for HTML5/CSS3 feature detection. Using the script generation tool you can pick the specific test functionality that you need and ignore everything that you don’t need. That way the script is kept as small as possible. An example of the custom script download screen is shown next. Notice that specific CSS3, HTML5, and related feature tests can be selected. Once you’ve downloaded your custom script you can add it into your web page using the standard <script> element and you’re ready to start using Modernizr. <script src="Scripts/Modernizr.js" type="text/javascript"></script>   Modernizr and the HTML Element Once you’ve add a script reference to Modernizr in a page it’ll go to work for you immediately. In fact, by adding the script several different CSS classes will be added to the page’s <html> element at runtime. These classes define what features the browser supports and what features it doesn’t support. Features that aren’t supported get a class name of “no-FeatureName”, for example “no-flexbox”. Features that are supported get a CSS class name based on the feature such as “canvas” or “websockets”. An example of classes added when running a page in Chrome is shown next:   <html class=" js flexbox canvas canvastext webgl no-touch geolocation postmessage websqldatabase indexeddb hashchange history draganddrop websockets rgba hsla multiplebgs backgroundsize borderimage borderradius boxshadow textshadow opacity cssanimations csscolumns cssgradients cssreflections csstransforms csstransforms3d csstransitions fontface generatedcontent video audio localstorage sessionstorage webworkers applicationcache svg inlinesvg smil svgclippaths"> Here’s an example of what the <html> element looks like at runtime with Internet Explorer 9:   <html class=" js no-flexbox canvas canvastext no-webgl no-touch geolocation postmessage no-websqldatabase no-indexeddb hashchange no-history draganddrop no-websockets rgba hsla multiplebgs backgroundsize no-borderimage borderradius boxshadow no-textshadow opacity no-cssanimations no-csscolumns no-cssgradients no-cssreflections csstransforms no-csstransforms3d no-csstransitions fontface generatedcontent video audio localstorage sessionstorage no-webworkers no-applicationcache svg inlinesvg smil svgclippaths">   When using Modernizr it’s a common practice to define an <html> element in your page with a no-js class added as shown next:   <html class="no-js">   You’ll see starter projects such as HTML5 Boilerplate (http://html5boilerplate.com) or Initializr (http://initializr.com) follow this approach (see my previous post for more information on HTML5 Boilerplate). By adding the no-js class it’s easy to tell if a browser has JavaScript enabled or not. If JavaScript is disabled then no-js will stay on the <html> element. If JavaScript is enabled, no-js will be removed by Modernizr and a js class will be added along with other classes that define supported/unsupported features. Working with HTML5 and CSS3 Features You can use the CSS classes added to the <html> element directly in your CSS files to determine what style properties to use based upon the features supported by a given browser. For example, the following CSS can be used to render a box shadow for browsers that support that feature and a simple border for browsers that don’t support the feature: .boxshadow #MyContainer { border: none; -webkit-box-shadow: #666 1px 1px 1px; -moz-box-shadow: #666 1px 1px 1px; } .no-boxshadow #MyContainer { border: 2px solid black; }   If a browser supports box-shadows the boxshadow CSS class will be added to the <html> element by Modernizr. It can then be associated with a given element. This example associates the boxshadow class with a div with an id of MyContainer. If the browser doesn’t support box shadows then the no-boxshadow class will be added to the <html> element and it can be used to render a standard border around the div. This provides a great way to leverage new CSS3 features in supported browsers while providing a graceful fallback for older browsers. In addition to using the CSS classes that Modernizr provides on the <html> element, you also use a global Modernizr object that’s created. This object exposes different properties that can be used to detect the availability of specific HTML5 or CSS3 features. For example, the following code can be used to detect canvas and local storage support. You can see that the code is much simpler than the code shown at the beginning of this post. It also has the added benefit of being tested by a large community of web developers around the world running a variety of browsers.   $(document).ready(function () { if (Modernizr.canvas) { //Add canvas code } if (Modernizr.localstorage) { //Add local storage code } }); The global Modernizr object can also be used to test for the presence of CSS3 features. The following code shows how to test support for border-radius and CSS transforms:   $(document).ready(function () { if (Modernizr.borderradius) { $('#MyDiv').addClass('borderRadiusStyle'); } if (Modernizr.csstransforms) { $('#MyDiv').addClass('transformsStyle'); } });   Several other CSS3 feature tests can be performed such as support for opacity, rgba, text-shadow, CSS animations, CSS transitions, multiple backgrounds, and more. A complete list of supported HTML5 and CSS3 tests that Modernizr supports can be found at http://www.modernizr.com/docs.   Loading Scripts using Modernizr In cases where a browser doesn’t support a specific feature you can either provide a graceful fallback or load a shim/polyfill script to fill in missing functionality where appropriate (more information about shims/polyfills can be found at https://github.com/Modernizr/Modernizr/wiki/HTML5-Cross-Browser-Polyfills). Modernizr has a built-in script loader that can be used to test for a feature and then load a script if the feature isn’t available. The script loader is built-into Modernizr and is also available as a standalone yepnope script (http://yepnopejs.com). It’s extremely easy to get started using the script loader and it can really simplify the process of loading scripts based on the availability of a particular browser feature. To load scripts dynamically you can use Modernizr’s load() function which accepts properties defining the feature to test (test property), the script to load if the test succeeds (yep property), the script to load if the test fails (nope property), and a script to load regardless of if the test succeeds or fails (both property). An example of using load() with these properties is show next: Modernizr.load({ test: Modernizr.canvas, yep: 'html5CanvasAvailable.js’, nope: 'excanvas.js’, both: 'myCustomScript.js' }); In this example Modernizr is used to not only load scripts but also to test for the presence of the canvas feature. If the target browser supports the HTML5 canvas then the html5CanvasAvailable.js script will be loaded along with the myCustomScript.js script (use of the yep property in this example is a bit contrived – it was added simply to demonstrate how the property can be used in the load() function). Otherwise, a polyfill script named excanvas.js will be loaded to add missing canvas functionality for Internet Explorer versions prior to 9. Once excanvas.js is loaded the myCustomScript.js script will be loaded. Because Modernizr handles loading scripts, you can also use it in creative ways. For example, you can use it to load local scripts when a 3rd party Content Delivery Network (CDN) such as one provided by Google or Microsoft is unavailable for whatever reason. The Modernizr documentation provides the following example that demonstrates the process for providing a local fallback for jQuery when a CDN is down:   Modernizr.load([ { load: '//ajax.googleapis.com/ajax/libs/jquery/1.6.4/jquery.js', complete: function () { if (!window.jQuery) { Modernizr.load('js/libs/jquery-1.6.4.min.js'); } } }, { // This will wait for the fallback to load and // execute if it needs to. load: 'needs-jQuery.js' } ]); This code attempts to load jQuery from the Google CDN first. Once the script is downloaded (or if it fails) the function associated with complete will be called. The function checks to make sure that the jQuery object is available and if it’s not Modernizr is used to load a local jQuery script. After all of that occurs a script named needs-jQuery.js will be loaded. Conclusion If you’re building applications that use some of the latest and greatest features available in HTML5 and CSS3 then Modernizr is an essential tool. By using it you can reduce the amount of custom code required to test for browser features and provide graceful fallbacks or even load shim/polyfill scripts for older browsers to help fill in missing functionality. 

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