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• Internet Explorer randomly drops sessions between pages in cakePHP

  - by Emerson Taymor

  Hello everyone, I've come across an extremely unusual bug that my team has literally no idea how to solve. Doing some research, I found some similar solutions that I thought would work, but alas did not. Here is my situation, let me know if I can provide additional insight to help solve the problem. The first step is that someone chooses a country via a flash map. Flash passes this region name (as well as a date) through the URL, which we then convert to a session. The next page contains no Flash and doesn't display the selected region, but it does hold on to it for further down the process. Everything works perfectly in Safari and Firefox; however, in IE sometimes unexpected results occur. Frequently (but not always), the session is dropped completely and no sessions are stored between the first and 2nd pages. Here are the steps that I have taken thus far, unsuccessfully: 1. Changed Security from Medium - Low 2. Changed CheckUserAgent from True - False 3. Changed storing of sessions from PHP - Database Some additional information that may be useful: I have tried printing out the session data in Debug (debug($_SESSION) on my view file and debug set to 2 in config). In Internet Explorer everything prints out as expected EXCEPT when the region and date don't get set. For example: If the region and date don't get set NOTHING is printed out for debug. I don't get the session details at the top, and I don't get the normal dump of calls at the bottom of the page either. I am not using redirection on these pages. Please let me know if you have ANY idea of what is causing this or any solutions. I am beyond frustrated and have tried as much as I can to solve this. Thanks!

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• Search engine recommendation for 100 sites of about 4000 pages

  - by fwkb

  I am looking for a search engine that can regularly (daily-ish) scan about 100 pages for changes and index an associated site if changes since the last scan are found. It should be able to handle about 100 sites, each averaging 4000 pages of about 5k average size, each on a different server (but only the one centralized search engine). Each of these sites will have a search form that gets submitted to this search engine. The results that are returned must be specific to the site that submitted them. I create the templates for the external sites, so I can give the search form a hidden field that specifies which site the form is submitted from. What would you recommend I look into? I would love to use a Python-based system for this, if feasible. I am currently using something called iSearch2. It doesn't seem very stable at this scale, the description of the product states it is not really intended to do multiple sites, is in PHP (which is less comfortable to me than Python), and has a few other shortcomings for my specific situation.

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• Drupal administration theme doesn't apply to Blocks pages (admin/build/block)

  - by hfidgen

  A site I'm creating for a customer in D6 has various images overlaying parts of the main content area. It looks very pretty and they have to be there for the general effect. The problem is, if you use this theme in the administration pages, the images get in the way of everything. My solution was to create a custom admin theme, based on the default one, which has these image areas disabled in the output template files - page.tpl.php The problem is that when you try and edit the blocks page, it uses the default theme and half the blocks admin settings are unclickable behind the images. I KNOW this is by design in Drupal, but it's annoying the hell out of me and is edging towards "bug" rather than "feature" in my mind. It also appears that there is no way of getting around it. You can edit /modules/blocks/block.admin.inc to force Drupal to show the blocks page in the chosen admin theme. BUT whichever changes you then make will not be transferred to the default theme, as Drupal treats each theme separately and each theme can have different block layouts. :x function block_admin_display($theme = NULL) { global $custom_theme; // If non-default theme configuration has been selected, set the custom theme. // $custom_theme = isset($theme) ? $theme : variable_get('theme_default', 'garland'); // Display admin theme $custom_theme = variable_get('admin_theme', '0'); // Fetch and sort blocks $blocks = _block_rehash(); usort($blocks, '_block_compare'); return drupal_get_form('block_admin_display_form', $blocks, $theme); } Can anyone help? the only thing I can think of is to push the $content area well below the areas where the image appear and use blocks only for content display. Thanks!

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• How someone using my Facebook website app can post to their pages timeline

  - by user1334414

  I have a website where businesses create content through a PHP backend system. Each time they create a new piece of content, I want it to publish to their Facebook pages timeline (not the users timeline). I have created the authenticate code: <div id="fb-root"></div> <script> window.fbAsyncInit = function() { FB.init({ appId : 'XXXXXXXXXX', status : true, cookie : true, xfbml : true, oauth : true, }); }; (function(d){ var js, id = 'facebook-jssdk'; if (d.getElementById(id)) {return;} js = d.createElement('script'); js.id = id; js.async = true; js.src = "//connect.facebook.net/en_US/all.js"; d.getElementsByTagName('head')[0].appendChild(js); }(document)); </script> <div class="fb-login-button" scope="manage_pages"> Login with Facebook </div> With manage_pages as a scope. I need to know how they can select which page they want the post to go to (if they have more than 1 page), and also how to automatically post to that pages wall when they submit the content (which is done via a PHP form). Thanks

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• How to control access to third party HTML pages

  - by Wylie

  Hello, We have a Learning Management System (LMS) that runs on its own server (IIS/Server 2003). Students must login with Forms authentication to gain access to the content. We want to offer access to third party flash and audio that is embedded in HTML pages hosted on the third party server (IIS/Server 2003). Currently we use a frame in a pop-up window that is populated via a simple URL to the third party HTML pages. How can the third party control access to their content, so that only students who launch the pop-up windows from our site can access their content? Since the content is mostly video and flash, we would prefer not to stream all of their content through our server to the Student. We have a programming staff, so we could maybe... - either post or get for our HTTP request to the third party server - we could use SSL - we could programmatically assign a global NT user account to all of our users and then do some kind of Active Directory login from the LMS server to the third party server - could the third party content be hosted at Amazon S3? Would this allow for secure access/download? These are just ideas. We really have no idea. Any suggestions would be greatly appreciated. TIA, Wylie

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• Stop Rewrite htaccess create random pages

  - by Vistol

  Recently I saw in my Webmaster tools that some random sites are linking to my site. Actually this is not an big issue. The issue comes when the pages that are linked are not real pages because of my httaccess file. This is the htaccess code that Im running: <pre> #Options +FollowSymLinks RewriteEngine on RewriteRule ^([^/\.]+)/?$ index.php?id=$1 [L] RewriteRule ^([0-9]+)/(.*)$ index.php?id=$1 [L] </pre> So the real URLs would be: mysite.com/folder/999/TITLE-OR-NAME But cecause I only check the 1st folder ($1) which is an I numberD, this htaccess file is allowing hackers linking to my site with random URLs like: mysite.com/folder/999/TITLE-OR-NAME1 mysite.com/folder/999/TITLE-OR-NAME2 mysite.com/folder/999/TITLE-OR-NAME3 mysite.com/folder/999/TITLE-OR-NAME4 mysite.com/folder/999/TITLE-OR-NAME5 The worst part comes when google tells me that I am duplicating content!!! Actually I am not duplicating content, the htaccess is duplicating it for me. And yes I know, Im a bad newbie programmer but Id really appreciate your help with this cause Im struggling to find a solution but it never. Thank you very much for all your support to this newbie :)

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• Sharepoint page menu items gone?

  - by Richard

  I'm running MOSS 2007 and have created a new site under an existing one using sitemanager.aspx. I've done this on two machines. on one of those everything works correctly, while on the other some of the menu items for pages in the site seem to be gone. Also on the faulty site I get "Access denied" when I click "Version history". The permissions on both sites should be the same. I attach a screenshot of how the menus differ from each other. The one to the right (the faulty one) is unfortunately not in English but the items appearing on it are "Open link in a new window", "Copy", "Edit page settings" and "Version history". "View properties" and some more items are missing! What could have caused this? Screenshot: I'm running MOSS 2007 and have created a new site under an existing one using sitemanager.aspx. I've done this on two machines. on one of those everything works correctly, while on the other some of the menu items for pages in the site seem to be gone. Also on the faulty site I get "Access denied" when I click "Version history". The permissions on both sites should be the same. I attach a screenshot of how the menus differ from each other. The one to the right (the faulty one) is unfortunately not in English but the items appearing on it are "Open link in a new window", "Copy", "Edit page settings" and "Version history". "View properties" and some more items are missing! What could have caused this? Screenshot: hxxp://i40.tinypic.com/302naxx.jpg

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• Wordpress nav not visible in pages like articles, blog & search

  - by kwek-kwek

  My wordpress*(a custom template)* nav is all working on all of the pages but now I found out that the Main nav doesn't show on this pages All pages e.g. search.php, single.php, index.php, page.php all has <?php get_header(); ?> I really don't know whats wrong. Here is the code for my header.php <?php /** * @package WordPress * @subpackage Default_Theme */ ?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" <?php language_attributes() ?>> <head> <meta http-equiv="Content-Type" content="<?php bloginfo('html_type'); ?>; charset=<?php bloginfo('charset'); ?>" /> <title><?php bloginfo('name'); ?> <?php wp_title(); ?></title> <link rel="stylesheet" href="<?php bloginfo('stylesheet_url'); ?>" type="text/css" media="screen,projection" /> <link rel="stylesheet" href="<?php bloginfo('template_url'); ?>/css/sifr.css" type="text/css" /> <script src="<?php bloginfo('template_url'); ?>/js/sifr.js" type="text/javascript"></script> <script src="<?php bloginfo('template_url'); ?>/js/sifr-config.js" type="text/javascript"></script> <script src="http://cdn.jquerytools.org/1.1.2/jquery.tools.min.js"></script> <?php wp_head(); ?> </head> <?php $current_page = $post->ID; $parent = 1; while($parent) { $page_query = $wpdb->get_row("SELECT post_name, post_parent FROM $wpdb->posts WHERE ID = '$current_page'"); $parent = $current_page = $page_query->post_parent; if(!$parent) $parent_name = $page_query->post_name; } ?> <body id="<?php echo (is_page()) ? "$parent_name" : ((is_home()) ? "blog" : ((is_search()) ? "other" : ((is_single()) ? "blog" : "blog"))); ?>"> <div id="BGtie"> <!--HEAD WRAPPER--> <div id="headwrapper"> <!--HEADER--> <div id="headContainer"> <div id="nameTag"> <a href="<?php echo get_option('home'); ?>/"><?php bloginfo('name'); ?></a> </div> <!--TOP NAV--> <div id="topNav"> <ul> <li><a href="<?php bloginfo('url'); ?>home">Home</a></li> <li><a href="#">Request info</a></li> <li><a href="#">Contact us</a></li> <?php do_action('icl_language_selector'); ?> </ul> </div> <!--END TOP NAV--> <!--MAIN NAV--> <?php if ( is_page() AND (strtolower(ICL_LANGUAGE_CODE) == 'fr') ) {include("main-nav-fr.php");} ?> <?php if (is_page() AND (strtolower(ICL_LANGUAGE_CODE) == 'en')) include("main-nav-en.php") ?> <!--END MAIN NAV--> </div> <!--END HEADER--> </div> <!--END HEAD WRAPPER--> </div>

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• Trying to run a codeigniter app on custom php

  - by hamstar

  I have a CodeIgniter app that I deployed to a server with php 5.2 and my dev box has 5.3, and some stuff doesn't work anymore. I didn't want to upgrade php and risk the other app on the server having issues. Anyway I compiled a custom PHP and added the following to a single .conf file in /etc/httpd/conf.d/zcid.conf with all the other conf files. <VirtualHost *:80> DocumentRoot /var/www/cid/app ServerName sub.example.co.nz </VirtualHost> <Directory "/var/www/cid/app"> authtype Basic authname "oh dear how did this get here i am no good with computer" authuserfile /path/to/auth require valid-user RewriteEngine on RewriteCond $1 !^(index\.php|robots\.txt|createEvent\.php|/cgi-bin) RewriteRule ^(.*)$ /index.php/$1 [L] AddHandler custom-php .php Action custom-php /cgi-bin/php53.cgi </Directory> In /var/www/cid/app I have the cgi-bin folder and the php53.cgi that I copied from /usr/local/php53/bin/php-cgi But now when I navigate to the subdomain it says: The requested URL /cgi-bin/php53.cgi/index.php/ was not found on this server. And if I try to browse to /cgi-bin it says (what it is supposed to?): You don't have permission to access /cgi-bin/ on this server. Quite confused now. Anyone know what to do here? Thanks :)

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• CloudFront with Custom Origin and ELB

  - by kmfk

  We are using CloudFront for our static assets but also wanted to allow for Gzip. We set up a new distribution with a custom origin pointing back to our application servers which are behind a elastic load balancer. We manually keep the files in sync across the cluster and update them when we publish. However, with this set up, we get nothing but Miss and RefreshHits from CloudFront, which so far has defeated the purpose. Is there any additional settings in order to use an ELB as your custom origin? In the docs, it references this as a viable solution. It appears when we point the distribution to a single server in our production cluster, cloudfront properly caches our assets. Is it possible that the sticky sessions cookie and the subsequent header that gets added by it could be an issue? Cache-Control: no-cache="set-cookie" //Added by load balancer Any ideas? FYI - currently, we have our custom origin pointing to a single EC2 instance, so caching is working correctly - in case you try to curl the file below. Example headers: curl -I http://static.quick-cdn.com/css/9850999.css HTTP/1.0 200 OK Accept-Ranges: bytes Cache-Control: max-age=3700 Cache-Control: no-cache="set-cookie" Content-Length: 23038 Content-Type: text/css Date: Thu, 12 Apr 2012 23:03:52 GMT Last-Modified: Thu, 12 Apr 2012 23:00:14 GMT Server: Apache/2.2.17 (Ubuntu) Vary: Accept-Encoding X-Cache: RefreshHit from cloudfront X-Amz-Cf-Id: K_q7Zy3_jdzlEJ85ukELVtdx1GmuXqApAbZZ7G0fPt0mxRMqPKX5pQ==,RzJmPku-rEIO9WlvuSoKa8hiAaR3dLk5KC4cQMWWrf_MDhmjWe8n6A== Via: 1.0 28c34f9fbf559a21ee16594849e4fc9c.cloudfront.net (CloudFront) Connection: close

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• MS Word custom dictionary making spellcheck slow - ideas?

  - by ezuk

  I have a user who edits technical materials. She uses MS Word's Custom Dictionary all the time for spelling; it has grown very large, and is now making spell check very slow. All of the advice I've read online says to disable the custom dictionary. This is an easy solution, but is not workable for the user, because she actually needs this dictionary. So, is there any way to optimize the custom dictionary and/or Word itself, so that a large dictionary file doesn't slow things down quite so badly? Many thanks. Update after suggestions: I ran contig on the file, and it reports just 1 frag, so that's not the issue I think. The file is 9.95KB -- 1,117 lines, each consisting of just a single word. I viewed the file using Notepad and none of the lines seems corrupted, strange, or overly long (no line seems to be over 10 chars or so). Both of your suggestions were helpful so I will upvote both; any further tips would be most welcome.

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• How to make quicksilver remember custom trigger

  - by corroded

  I am trying to make a custom trigger for my shell/apple script file to run so I can just launch my dev environment at the push of a button. So basically: I have a shell script(and some apple script included) in ~ named start_server.sh which does 3 things: start up solr server start up memcached start up script/server I have a saved quicksilver command(.qs) that opens up start_server.sh(so start_server.sh, then the action is "Run in Terminal") I created a custom trigger that calls this saved qs command. I did that then tested it and it works. I then tried to double check it so I quit quicksilver and when I checked the triggers it just said: "Open (null)" as the action. I set the trigger again and when i restarted QS the same thing happened again. I don't know why but my old custom trigger to open terminal has worked since forever so why doesn't this one work? Here's a screenie of the triggers after I restart QS: http://grab.by/4XWW If you have any other suggestion on how to make a "push button" start for my server then please do so :) Thanks! As an added note, I have already tried the steps on this thread but to no avail: http://groups.google.com/group/blacktree-quicksilver/browse_thread/thread/7b65ecf6625f8989

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• how to ajax your confluence pages so slow macros dont slow down page load

  - by oo

  some pages that use macros like: topusers or popularlabels are really slow to load. Is there any way to have this load asynchronously through ajax instead of having this block the initial page load ?

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• Can google “see” this custom javascript code which displays links from an external site to mine

  - by webmasters

  I have a javascript code on my site who displays links from another site. This is what I have on my source before: <script language="JavaScript" type="text/javascript">showLink(1);</script> This is what I have copied from my source after the page has loaded: <script language="JavaScript" type="text/javascript">showLink(1);</script><a rel="nofollow" target="_blank" class="anc" href="http://x5.external_site.net/sc/out.php?s=5483&amp;o=http%3A%2F%2Fwww.bluetooth.com">Bluetooth Devices</a> Can google see this link?

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• shtml pages are not working in iis7

  - by Vivek Chandraprakash

  shtml pages are not displayed in iis7. i get the following error when tried to access shtm file The page you are requesting cannot be served because of the extension configuration. If the page is a script, add a handler. If the file should be downloaded, add a MIME map. pls help -Vivek

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• how to ajax your confluence pages so slow macros dont slow down page load

  - by oo

  some pages that use macros like: topusers or popularlabels are really slow to load. Is there any way to have this load asynchronously through ajax instead of having this block the initial page load ?

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• jQuery Ajax Error Handling – How To Show Custom Error Messages

  - by schnieds

  So you want to make your error feedback nice for your users…Kind of an ironic statement isn’t it? We obviously want to avoid errors if at all possible in our applications, but when errors do occur then we want to provide some nice feedback to our users. The worst thing that can happen is to blow up a huge server exception page when something goes wrong or equally bad is not providing any feedback at all and leaving the user in the dark. Although I do not recommend displaying actual .NET Framework exception messages or stack traces to the user in most instances; they are usually not helpful to the user and can be a security concern.... [Read More]Aaron Schniederhttp://www.churchofficeonline.com

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• Access UIButton's titleLabel with custom background image

  - by Meltemi

  Quick one: I have a custom button image that I want to use but I still want to change the text of the button with setTitle:forState:. When I use a "custom" button in IB I lose the Title view. When I use Rounded Rect in IB the custom image appears scrunched w/in the Rounded Rect button. Why is this so difficult?

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• Prevent Custom Entity being deleted from Entity Framework during Update Model Wizard

  - by rbg

  In Entity Framework v1 If you create a Custom Entity to map it to a Stored Procedure during FunctionImport and then Select "Update Model from Database" the Update Model Wizard removes the Custom Entity (as added Manually in the SSDL XML prior to functionImport) from the SSDL. Does anyone know if this limitation has been dealt with Entity Framework v4? I mean is there a way to prevent the Wizard from removing the Custom Entity from the Storage Schema (SSDL) during Model Update from Database????

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• Knockoutjs - stringify to handling observables and custom events

  - by Renso

  Goal: Once you viewmodel has been built and populated with data, at some point it goal of it all is to persist the data to the database (or some other media). Regardless of where you want to save it, your client-side viewmodel needs to be converted to a JSON string and sent back to the server. Environment considerations: jQuery 1.4.3+ Knockoutjs version 1.1.2   How to: So let’s set the stage, you are using Knockoutjs and you have a viewmodel with some Knockout dependencies. You want to make sure it is in the proper JSON format and via ajax post it to the server for persistence.   First order of business is to deal with the viewmodel (JSON) object. To most the JSON stringifier sounds familiar. The JSON stringifier converts JavaScript data structures into JSON text. JSON does not support cyclic data structures, so be careful to not give cyclical structures to the JSON stringifier. You may ask, is this the best way to do it? What about those observables and other Knockout properties that I don’t want to persist or want their actual value persisted and not their function, etc. Not sure if you were aware, but KO already has a method; ko.utils.stringifyJson() - it's mostly just a wrapper around JSON.stringify. (which is native in some browsers, and can be made available by referencing json2.js in others). What does it do that the regular stringify does not is that it automatically converts observable, dependentObservable, or observableArray to their underlying value to JSON. Hold on! There is a new feature in this version of Knockout, the ko.toJSON. It is part of the core library and it will clone the view model’s object graph, so you don’t mess it up after you have stringified  it and unwrap all its observables. It's smart enough to avoid reference cycles. Since you are using the MVVM pattern it would assume you are not trying to reference DOM nodes from your view. Wait a minute. I can already see this info on the http://knockoutjs.com/examples/contactsEditor.html website, why mention it all here? First of this is a much nicer blog, no orange ? At this time, you may want to have a look at the blog and see what I am talking about. See the save event, how they stringify the view model’s contacts only? That’s cool but what if your view model is a representation of your object you want to persist, meaning it has no property that represents the json object you want to persist, it is the view model itself. The example in http://knockoutjs.com/examples/contactsEditor.html assumes you have a list of contacts you may want to persist. In the example here, you want to persist the view model itself. The viewmodel here looks something like this:     var myViewmodel = {         accountName: ko.observable(""),         accountType: ko.observable("Active")     };     myViewmodel.isItActive = ko.dependentObservable(function () {         return myViewmodel.accountType() == "Active";     });     myViewmodel.clickToSaveMe = function() {         SaveTheAccount();     }; Here is the function in charge of saving the account: Function SaveTheAccount() {     $.ajax({         data: ko.toJSON(viewmodel),         url: $('#ajaxSaveAccountUrl').val(),         type: "POST",         dataType: "json",         async: false,         success: function (result) {             if (result && result.Success == true) {                 $('#accountMessage').html('<span class="fadeMyContainerSlowly">The account has been saved</span>').show();                 FadeContainerAwaySlowly();             }         },         error: function (xmlHttpRequest, textStatus, errorThrown) {             alert('An error occurred: ' + errorThrown);         }     }); //ajax }; Try run this and your browser will eventually freeze up or crash. Firebug will tell you that you have a repetitive call to the first function call in your model that keeps firing infinitely.  What is happening is that Knockout serializes the view model to a JSON string by traversing the object graph and firing off the functions, again-and-again. Not sure why it does that, but it does. So what is the work around: Nullify your function calls and then post it:         var lightweightModel = viewmodel.clickToSaveMe = null;         data: ko.toJSON(lightweightModel), So then I traced the JSON string on the server and found it having issues with primitive types. C#, by the way. So I changed ko.toJSON(model) to ko.toJS(model), and that solved my problem. Of course you could just create a property on the viewmodel for the account itself, so you only have to serialize the property and not the entire viewmodel. If that is an option then that would be the way to go. If your view model contains other properties in the view model that you also want to post then that would not be an option and then you’ll know what to watch out for. Hope this helps.

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• Professional Custom Logo Design vs. Mr. Right

  John is an ex-marine and ex-employee of general motors. He recently lost his job working as a welder on the assembly lines of one of GM manufacturing plants. John has traveled a lot and knows a lot a... [Author: Emily Matthew - Web Design and Development - March 31, 2010]

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• How to use Blazeds with a custom classloader?

  - by festerwim

  Hi, has anybody tried using a custom classloader with BlazeDS? We have a web application using BlazeDS and we can convert Java objects in to ActionScript object and back without problems in the main application. However, we also have a plug-in mechanism based on a custom classloader. BlazeDS cannot map the types contained in jar files of that custom classloader since I don't know how to tell it to BlazeDS. Has anybody already done this? The livedocs of TypeMarshallingcontext show a setClassloader() method, but since the context seems to be a singleton, I assume this will not work if you have multiple custom classloaders (we have 1 for each plugin that is deployed) regards, Wim

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• Custom UIView built with Interface Builder accessible/positionable via Interface Builder

  - by Nader

  This shouldn't be this confusing. I have a custom UIView with a bunch on controls on it. UILabels, buttons, etc. I've created this Nib using Interface Builder. I want to be able to position this custom uiview on another UIView using the interface builder. How do I link my UIView custom class, to the nib? initWithCoder gets called, but I want this class to get loaded from the nib. Thanks

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• A couple of questions on exceptions/flow control and the application of custom exceptions

  - by dotnetdev

  1) Custom exceptions can help make your intentions clear. How can this be? The intention is to handle or log the exception, regardless of whether the type is built-in or custom. The main reason I use custom exceptions is to not use one exception type to cover the same problem in different contexts (eg parameter is null in system code which may be effect by an external factor and an empty shopping basket). However, the partition between system and business-domain code and using different exception types seems very obvious and not making the most of custom exceptions. Related to this, if custom exceptions cover the business exceptions, I could also get all the places which are sources for exceptions at the business domain level using "Find all references". Is it worth adding exceptions if you check the arguments in a method for being null, use them a few times, and then add the catch? Is it a realistic risk that an external factor or some other freak cause could cause the argument to be null after being checked anyway? 2) What does it mean when exceptions should not be used to control the flow of programs and why not? I assume this is like: if (exceptionVariable != null) { } Is it generally good practise to fill every variable in an exception object? As a developer, do you expect every possible variable to be filled by another coder?

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• Using NServiceBus behind a custom web service

  - by Michael Stephenson

  In this post I'd like to talk about an architecture scenario we had recently and how we were able to utilise NServiceBus to help us address this problem. Scenario Cognos is a reporting system used by one of my clients. A while back we developed a web service façade to allow line of business applications to be able to access reports from Cognos to support their various functions. The service was intended to provide access to reports which were quick running reports or pre-generated reports which could be accessed real-time on demand. One of the key aims of the web service was to provide a simple generic interface to allow applications to get any report without needing to worry about the complex .net SDK for Cognos. The web service also supported multi-hop kerberos delegation so that report data could be accesses under the context of the end user. This service was working well for a period of time. The Problem The problem we encountered was that reports were now also required to be available to batch processes. The original design was optimised for low latency so users would enjoy a positive experience, however when the batch processes started to request 250+ concurrent reports over an extended period of time you can begin to imagine the sorts of problems that come into play. The key problems this new scenario caused are: Users may be affected and the latency of on demand reports was significantly slower The Cognos infrastructure was not scaled sufficiently to be able to cope with these long peaks of load From a cost perspective it just isn't feasible to scale the Cognos infrastructure to be able to handle the load when it is only for a couple of hour window each night. We really needed to introduce a second pattern for accessing this service which would support high through-put scenarios. We also had little control over the batch process in terms of being able to throttle its load. We could however make some changes to the way it accessed the reports. The Approach My idea was to introduce a throttling mechanism between the Web Service Façade and Cognos. This would allow the batch processes to push reports requests hard at the web service which we were confident the web service can handle. The web service would then queue these requests and process them behind the scenes and make a call back to the batch application to provide the report once it had been accessed. In terms of technology we had some limitations because we were not able to use WCF or IIS7 where the MSMQ-Activated WCF services could have helped, but we did have MSMQ as an option and I thought NServiceBus could do just the job to help us here. The flow of how this would work was as follows: The batch applications would send a request for a report to the web service The web service uses NServiceBus to send the message to a Queue The NServiceBus Generic Host is running as a windows service with a message handler which subscribes to these messages The message handler gets the message, accesses the report from Cognos The message handler calls back to the original batch application, this is decoupled because the calling application provides a call back url The report gets into the batch application and is processed as normal This approach looks something like the below diagram: The key points are an application wanting to take advantage of the batch driven reports needs to do the following: Implement our call back contract Make a call to the service providing a call back url Provide a correlation ID so it knows how to tie each response back to its request What does NServiceBus offer in this solution So this scenario is not the typical messaging service bus type of solution people implement with NServiceBus, but it did offer the following: Simplified interaction with MSMQ Offered the ability to configure the number of processes working through the queue so we could find a balance between load on Cognos versus the applications end to end processing time NServiceBus offers retries and a way to manage failed messages NServiceBus offers a high availability setup The simple thing is that NServiceBus gave us the platform to build the solution on. We just implemented a message handler which functionally processed a message and we could rely on NServiceBus to do all of the hard work around managing the queues and all of the lower level things that would have took ages to write to any kind of robust level. Conclusion With this approach we were able to deal with a fairly significant performance issue with out too much rework. Hopefully this write up gives people some insight into ideas on how to leverage the excellent NServiceBus framework to help solve integration and high through-put scenarios.

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