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• SQL Azure Reporting Limited CTP Arrived

  - by Shaun

  It’s about 3 months later when I registered the SQL Azure Reporting CTP on the Microsoft Connect after TechED 2010 China. Today when I checked my mailbox I found that the SQL Azure team had just accepted my request and sent the activation code over to me. So let’s have a look on the new SQL Azure Reporting.   Concept The SQL Azure Reporting provides cloud-based reporting as a service, built on SQL Server Reporting Services and SQL Azure technologies. Cloud-based reporting solutions such as SQL Azure Reporting provide many benefits, including rapid provisioning, cost-effective scalability, high availability, and reduced management overhead for report servers; and secure access, viewing, and management of reports. By using the SQL Azure Reporting service, we can do: Embed the Visual Studio Report Viewer ADO.NET Ajax control or Windows Form control to view the reports deployed on SQL Azure Reporting Service in our web or desktop application. Leverage the SQL Azure Reporting SOAP API to manage and retrieve the report content from any kinds of application. Use the SQL Azure Reporting Service Portal to navigate and view the reports deployed on the cloud. Since the SQL Azure Reporting was built based on the SQL Server 2008 R2 Reporting Service, we can use any tools we are familiar with, such as the SQL Server Integration Studio, Visual Studio Report Viewer. The SQL Azure Reporting Service runs as a remote SQL Server Reporting Service just on the cloud rather than on a server besides us.   Establish a New SQL Azure Reporting Let’s move to the windows azure deveploer portal and click the Reporting item from the left side navigation bar. If you don’t have the activation code you can click the Sign Up button to send a requirement to the Microsoft Connect. Since I already recieved the received code mail I clicked the Provision button. Then after agree the terms of the service I will select the subscription for where my SQL Azure Reporting CTP should be provisioned. In this case I selected my free Windows Azure Pass subscription. Then the final step, paste the activation code and enter the password of our SQL Azure Reporting Service. The user name of the SQL Azure Reporting will be generated by SQL Azure automatically. After a while the new SQL Azure Reporting Server will be shown on our developer portal. The Reporting Service URL and the user name will be shown as well. We can reset the password from the toolbar button.   Deploy Report to SQL Azure Reporting If you are familiar with SQL Server Reporting Service you will find this part will be very similar with what you know and what you did before. Firstly we open the SQL Server Business Intelligence Development Studio and create a new Report Server Project. Then we will create a shared data source where the report data will be retrieved from. This data source can be SQL Azure but we can use local SQL Server or other database if it opens the port up. In this case we use a SQL Azure database located in the same data center of our reporting service. In the Credentials tab page we entered the user name and password to this SQL Azure database. The SQL Azure Reporting CTP only available at the North US Data Center now so that the related SQL Server and hosted service might be better to select the same data center to avoid the external data transfer fee. Then we create a very simple report, just retrieve all records from a table named Members and have a table in the report to list them. In the data source selection step we choose the shared data source we created before, then enter the T-SQL to select all records from the Member table, then put all fields into the table columns. The report will be like this as following In order to deploy the report onto the SQL Azure Reporting Service we need to update the project property. Right click the project node from the solution explorer and select the property item. In the Target Server URL item we will specify the reporting server URL of our SQL Azure Reporting. We can go back to the developer portal and select the reporting node from the left side, then copy the Web Service URL and paste here. But notice that we need to append “/reportserver” after pasted. Then just click the Deploy menu item in the context menu of the project, the Visual Studio will compile the report and then upload to the reporting service accordingly. In this step we will be prompted to input the user name and password of our SQL Azure Reporting Service. We can get the user name from the developer portal, just next to the Web Service URL in the SQL Azure Reporting page. And the password is the one we specified when created the reporting service. After about one minute the report will be deployed succeed.   View the Report in Browser SQL Azure Reporting allows us to view the reports which deployed on the cloud from a standard browser. We copied the Web Service URL from the reporting service main page and appended “/reportserver” in HTTPS protocol then we will have the SQL Azure Reporting Service login page. After entered the user name and password of the SQL Azure Reporting Service we can see the directories and reports listed. Click the report will launch the Report Viewer to render the report.   View Report in a Web Role with the Report Viewer The ASP.NET and Windows Form Report Viewer works well with the SQL Azure Reporting Service as well. We can create a ASP.NET Web Role and added the Report Viewer control in the default page. What we need to change to the report viewer are Change the Processing Mode to Remote. Specify the Report Server URL under the Server Remote category to the URL of the SQL Azure Reporting Web Service URL with “/reportserver” appended. Specify the Report Path to the report which we want to display. The report name should NOT include the extension name. For example my report was in the SqlAzureReportingTest project and named MemberList.rdl then the report path should be /SqlAzureReportingTest/MemberList. And the next one is to specify the SQL Azure Reporting Credentials. We can use the following class to wrap the report server credential. 1: private class ReportServerCredentials : IReportServerCredentials 2: { 3: private string _userName; 4: private string _password; 5: private string _domain; 6:  7: public ReportServerCredentials(string userName, string password, string domain) 8: { 9: _userName = userName; 10: _password = password; 11: _domain = domain; 12: } 13:  14: public WindowsIdentity ImpersonationUser 15: { 16: get 17: { 18: return null; 19: } 20: } 21:  22: public ICredentials NetworkCredentials 23: { 24: get 25: { 26: return null; 27: } 28: } 29:  30: public bool GetFormsCredentials(out Cookie authCookie, out string user, out string password, out string authority) 31: { 32: authCookie = null; 33: user = _userName; 34: password = _password; 35: authority = _domain; 36: return true; 37: } 38: } And then in the Page_Load method, pass it to the report viewer. 1: protected void Page_Load(object sender, EventArgs e) 2: { 3: ReportViewer1.ServerReport.ReportServerCredentials = new ReportServerCredentials( 4: "<user name>", 5: "<password>", 6: "<sql azure reporting web service url>"); 7: } Finally deploy it to Windows Azure and enjoy the report.   Summary In this post I introduced the SQL Azure Reporting CTP which had just available. Likes other features in Windows Azure, the SQL Azure Reporting is very similar with the SQL Server Reporting. As you can see in this post we can use the existing and familiar tools to build and deploy the reports and display them on a website. But the SQL Azure Reporting is just in the CTP stage which means It is free. There’s no support for it. Only available at the North US Data Center. You can get more information about the SQL Azure Reporting CTP from the links following SQL Azure Reporting Limited CTP at MSDN SQL Azure Reporting Samples at TechNet Wiki You can download the solutions and the projects used in this post here.   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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• How can I get penetration depth from Minkowski Portal Refinement / Xenocollide?

  - by Raven Dreamer

  I recently got an implementation of Minkowski Portal Refinement (MPR) successfully detecting collision. Even better, my implementation returns a good estimate (local minimum) direction for the minimum penetration depth. So I took a stab at adjusting the algorithm to return the penetration depth in an arbitrary direction, and was modestly successful - my altered method works splendidly for face-edge collision resolution! What it doesn't currently do, is correctly provide the minimum penetration depth for edge-edge scenarios, such as the case on the right: What I perceive to be happening, is that my current method returns the minimum penetration depth to the nearest vertex - which works fine when the collision is actually occurring on the plane of that vertex, but not when the collision happens along an edge. Is there a way I can alter my method to return the penetration depth to the point of collision, rather than the nearest vertex? Here's the method that's supposed to return the minimum penetration distance along a specific direction: public static Vector3 CalcMinDistance(List<Vector3> shape1, List<Vector3> shape2, Vector3 dir) { //holding variables Vector3 n = Vector3.zero; Vector3 swap = Vector3.zero; // v0 = center of Minkowski sum v0 = Vector3.zero; // Avoid case where centers overlap -- any direction is fine in this case //if (v0 == Vector3.zero) return Vector3.zero; //always pass in a valid direction. // v1 = support in direction of origin n = -dir; //get the differnce of the minkowski sum Vector3 v11 = GetSupport(shape1, -n); Vector3 v12 = GetSupport(shape2, n); v1 = v12 - v11; //if the support point is not in the direction of the origin if (v1.Dot(n) <= 0) { //Debug.Log("Could find no points this direction"); return Vector3.zero; } // v2 - support perpendicular to v1,v0 n = v1.Cross(v0); if (n == Vector3.zero) { //v1 and v0 are parallel, which means //the direction leads directly to an endpoint n = v1 - v0; //shortest distance is just n //Debug.Log("2 point return"); return n; } //get the new support point Vector3 v21 = GetSupport(shape1, -n); Vector3 v22 = GetSupport(shape2, n); v2 = v22 - v21; if (v2.Dot(n) <= 0) { //can't reach the origin in this direction, ergo, no collision //Debug.Log("Could not reach edge?"); return Vector2.zero; } // Determine whether origin is on + or - side of plane (v1,v0,v2) //tests linesegments v0v1 and v0v2 n = (v1 - v0).Cross(v2 - v0); float dist = n.Dot(v0); // If the origin is on the - side of the plane, reverse the direction of the plane if (dist > 0) { //swap the winding order of v1 and v2 swap = v1; v1 = v2; v2 = swap; //swap the winding order of v11 and v12 swap = v12; v12 = v11; v11 = swap; //swap the winding order of v11 and v12 swap = v22; v22 = v21; v21 = swap; //and swap the plane normal n = -n; } /// // Phase One: Identify a portal while (true) { // Obtain the support point in a direction perpendicular to the existing plane // Note: This point is guaranteed to lie off the plane Vector3 v31 = GetSupport(shape1, -n); Vector3 v32 = GetSupport(shape2, n); v3 = v32 - v31; if (v3.Dot(n) <= 0) { //can't enclose the origin within our tetrahedron //Debug.Log("Could not reach edge after portal?"); return Vector3.zero; } // If origin is outside (v1,v0,v3), then eliminate v2 and loop if (v1.Cross(v3).Dot(v0) < 0) { //failed to enclose the origin, adjust points; v2 = v3; v21 = v31; v22 = v32; n = (v1 - v0).Cross(v3 - v0); continue; } // If origin is outside (v3,v0,v2), then eliminate v1 and loop if (v3.Cross(v2).Dot(v0) < 0) { //failed to enclose the origin, adjust points; v1 = v3; v11 = v31; v12 = v32; n = (v3 - v0).Cross(v2 - v0); continue; } bool hit = false; /// // Phase Two: Refine the portal int phase2 = 0; // We are now inside of a wedge... while (phase2 < 20) { phase2++; // Compute normal of the wedge face n = (v2 - v1).Cross(v3 - v1); n.Normalize(); // Compute distance from origin to wedge face float d = n.Dot(v1); // If the origin is inside the wedge, we have a hit if (d > 0 ) { //Debug.Log("Do plane test here"); float T = n.Dot(v2) / n.Dot(dir); Vector3 pointInPlane = (dir * T); return pointInPlane; } // Find the support point in the direction of the wedge face Vector3 v41 = GetSupport(shape1, -n); Vector3 v42 = GetSupport(shape2, n); v4 = v42 - v41; float delta = (v4 - v3).Dot(n); float separation = -(v4.Dot(n)); if (delta <= kCollideEpsilon || separation >= 0) { //Debug.Log("Non-convergance detected"); //Debug.Log("Do plane test here"); return Vector3.zero; } // Compute the tetrahedron dividing face (v4,v0,v1) float d1 = v4.Cross(v1).Dot(v0); // Compute the tetrahedron dividing face (v4,v0,v2) float d2 = v4.Cross(v2).Dot(v0); // Compute the tetrahedron dividing face (v4,v0,v3) float d3 = v4.Cross(v3).Dot(v0); if (d1 < 0) { if (d2 < 0) { // Inside d1 & inside d2 ==> eliminate v1 v1 = v4; v11 = v41; v12 = v42; } else { // Inside d1 & outside d2 ==> eliminate v3 v3 = v4; v31 = v41; v32 = v42; } } else { if (d3 < 0) { // Outside d1 & inside d3 ==> eliminate v2 v2 = v4; v21 = v41; v22 = v42; } else { // Outside d1 & outside d3 ==> eliminate v1 v1 = v4; v11 = v41; v12 = v42; } } } return Vector3.zero; } }

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• Using CMS for App Configuration - Part 1, Deploying Umbraco

  - by Elton Stoneman

  Originally posted on: http://geekswithblogs.net/EltonStoneman/archive/2014/06/04/using-cms-for-app-configurationndashpart-1-deploy-umbraco.aspxSince my last post on using CMS for semi-static API content, How about a new platform for your next API… a CMS?, I’ve been using the idea for centralized app configuration, and this post is the first in a series that will walk through how to do that, step-by-step. The approach gives you a platform-independent, easily configurable way to specify your application configuration for different environments, with a built-in approval workflow, change auditing and the ability to easily rollback to previous settings. It’s like Azure Web and Worker Roles where you can specify settings that change at runtime, but it's not specific to Azure - you can use it for any app that needs changeable config, provided it can access the Internet. The series breaks down into four posts: Deploying Umbraco – the CMS that will store your configurable settings and the current values; Publishing your config – create a document type that encapsulates your settings and a template to expose them as JSON; Consuming your config – in .NET, a simple client that uses dynamic objects to access settings; Config lifecycle management – how to publish, audit, and rollback settings. Let’s get started. Deploying Umbraco There’s an Umbraco package on Azure Websites, so deploying your own instance is easy – but there are a couple of things to watch out for, so this step-by-step will put you in a good place. Create From Gallery The easiest way to get started is with an Azure subscription, navigate to add a new Website and then Create From Gallery. Under CMS, you’ll see an Umbraco package (currently at version 7.1.3): Configure Your App For high availability and scale, you’ll want your CMS on separate kit from anything else you have in Azure, so in the configuration of Umbraco I’d create a new SQL Azure database – which Umbraco will use to store all its content: You can use the free 20mb database option if you don’t have demanding NFRs, or if you’re just experimenting. You’ll need to specify a password for a SQL Server account which the Umbraco service will use, and changing from the default username umbracouser is probably wise. Specify Database Settings You can create a new database on an existing server if you have one, or create new. If you create a new server *do not* use the same username for the database server login as you used for the Umbraco account. If you do, the deployment will fail later. Think of this as the SQL Admin account that you can use for managing the db, the previous account was the service account Umbraco uses to connect. Make Tea If you have a fast kettle. It takes about two minutes for Azure to create and provision the website and the database. Install Umbraco So far we’ve deployed an empty instance of Umbraco using the Azure package, and now we need to browse to the site and complete installation. My Website was called my-app-config, so to complete installation I browse to http://my-app-config.azurewebsites.net:   Enter the credentials you want to use to login – this account will have full admin rights to the Umbraco instance. Note that between deploying your new Umbraco instance and completing installation in this step, anyone can browse to your website and complete the installation themselves with their own credentials, if they know the URL. Remote possibility, but it’s there. From this page *do not* click the big green Install button. If you do, Umbraco will configure itself with a local SQL Server CE database (.sdf file on the Web server), and ignore the SQL Azure database you’ve carefully provisioned and may be paying for. Instead, click on the Customize link and: Configure Your Database You need to enter your SQL Azure database details here, so you’ll have to get the server name from the Azure Management Console. You don’t need to explicitly grant access to your Umbraco website for the database though. Click Continue and you’ll be offered a “starter” website to install: If you don’t know Umbraco at all (but you are familiar with ASP.NET MVC) then a starter website is worthwhile to see how it all hangs together. But after a while you’ll have a bunch of artifacts in your CMS that you don’t want and you’ll have to work out which you can safely delete. So I’d click “No thanks, I do not want to install a starter website” and give yourself a clean Umbraco install. When it completes, the installation will log you in to the welcome screen for managing Umbraco – which you can access from http://my-app-config.azurewebsites.net/umbraco: That’s It Easy. Umbraco is installed, using a dedicated SQL Azure instance that you can separately scale, sync and backup, and ready for your content. In the next post, we’ll define what our app config looks like, and publish some settings for the dev environment.

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• Overwriting TFS Web Services

  - by javarg

  In this blog I will share a technique I used to intercept TFS Web Services calls. This technique is a very invasive one and requires you to overwrite default TFS Web Services behavior. I only recommend taking such an approach when other means of TFS extensibility fail to provide the same functionality (this is not a supported TFS extensibility point). For instance, intercepting and aborting a Work Item change operation could be implemented using this approach (consider TFS Subscribers functionality before taking this approach, check Martin’s post about subscribers). So let’s get started. The technique consists in versioning TFS Web Services .asmx service classes. If you look into TFS’s ASMX services you will notice that versioning is supported by creating a class hierarchy between different product versions. For instance, let’s take the Work Item management service .asmx. Check the following .asmx file located at: %Program Files%\Microsoft Team Foundation Server 2010\Application Tier\Web Services\_tfs_resources\WorkItemTracking\v3.0\ClientService.asmx The .asmx references the class Microsoft.TeamFoundation.WorkItemTracking.Server.ClientService3: <%-- Copyright (c) Microsoft Corporation. All rights reserved. --%> <%@ webservice language="C#" Class="Microsoft.TeamFoundation.WorkItemTracking.Server.ClientService3" %> .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; } The inheritance hierarchy for this service class follows: Note the naming convention used for service versioning (ClientService3, ClientService2, ClientService). We will need to overwrite the latest service version provided by the product (in this case ClientService3 for TFS 2010). The following example intercepts and analyzes WorkItem fields. Suppose we need to validate state changes with more advanced logic other than the provided validations/constraints of the process template. Important: Backup the original .asmx file and create one of your own. Create a Visual Studio Web App Project and include a new ASMX Web Service in the project Add the following references to the project (check the folder %Program Files%\Microsoft Team Foundation Server 2010\Application Tier\Web Services\bin\): Microsoft.TeamFoundation.Framework.Server.dll Microsoft.TeamFoundation.Server.dll Microsoft.TeamFoundation.Server.dll Microsoft.TeamFoundation.WorkItemTracking.Client.QueryLanguage.dll Microsoft.TeamFoundation.WorkItemTracking.Server.DataAccessLayer.dll Microsoft.TeamFoundation.WorkItemTracking.Server.DataServices.dll Replace the default service implementation with the something similar to the following code: Code Snippet /// <summary> /// Inherit from ClientService3 to overwrite default Implementation /// </summary> [WebService(Namespace = "http://schemas.microsoft.com/TeamFoundation/2005/06/WorkItemTracking/ClientServices/03", Description = "Custom Team Foundation WorkItemTracking ClientService Web Service")] public class CustomTfsClientService : ClientService3 {     [WebMethod, SoapHeader("requestHeader", Direction = SoapHeaderDirection.In)]     public override bool BulkUpdate(         XmlElement package,         out XmlElement result,         MetadataTableHaveEntry[] metadataHave,         out string dbStamp,         out Payload metadata)     {         var xe = XElement.Parse(package.OuterXml);         // We only intercept WorkItems Updates (we can easily extend this sample to capture any operation).         var wit = xe.Element("UpdateWorkItem");         if (wit != null)         {             if (wit.Attribute("WorkItemID") != null)             {                 int witId = (int)wit.Attribute("WorkItemID");                 // With this Id. I can query TFS for more detailed information, using TFS Client API (assuming the WIT already exists).                 var stateChanged =                     wit.Element("Columns").Elements("Column").FirstOrDefault(c => (string)c.Attribute("Column") == "System.State");                 if (stateChanged != null)                 {                     var newStateName = stateChanged.Element("Value").Value;                     if (newStateName == "Resolved")                     {                         throw new Exception("Cannot change state to Resolved!");                     }                 }             }         }         // Finally, we call base method implementation         return base.BulkUpdate(package, out result, metadataHave, out dbStamp, out metadata);     } } .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; } 4. Build your solution and overwrite the original .asmx with the new implementation referencing our new service version (don’t forget to backup it up first). 5. Copy your project’s .dll into the following path: %Program Files%\Microsoft Team Foundation Server 2010\Application Tier\Web Services\bin 6. Try saving a WorkItem into the Resolved state. Enjoy!

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• ParallelWork: Feature rich multithreaded fluent task execution library for WPF

  - by oazabir

  ParallelWork is an open source free helper class that lets you run multiple work in parallel threads, get success, failure and progress update on the WPF UI thread, wait for work to complete, abort all work (in case of shutdown), queue work to run after certain time, chain parallel work one after another. It’s more convenient than using .NET’s BackgroundWorker because you don’t have to declare one component per work, nor do you need to declare event handlers to receive notification and carry additional data through private variables. You can safely pass objects produced from different thread to the success callback. Moreover, you can wait for work to complete before you do certain operation and you can abort all parallel work while they are in-flight. If you are building highly responsive WPF UI where you have to carry out multiple job in parallel yet want full control over those parallel jobs completion and cancellation, then the ParallelWork library is the right solution for you. I am using the ParallelWork library in my PlantUmlEditor project, which is a free open source UML editor built on WPF. You can see some realistic use of the ParallelWork library there. Moreover, the test project comes with 400 lines of Behavior Driven Development flavored tests, that confirms it really does what it says it does. The source code of the library is part of the “Utilities” project in PlantUmlEditor source code hosted at Google Code. The library comes in two flavors, one is the ParallelWork static class, which has a collection of static methods that you can call. Another is the Start class, which is a fluent wrapper over the ParallelWork class to make it more readable and aesthetically pleasing code. ParallelWork allows you to start work immediately on separate thread or you can queue a work to start after some duration. You can start an immediate work in a new thread using the following methods: void StartNow(Action doWork, Action onComplete) void StartNow(Action doWork, Action onComplete, Action<Exception> failed) For example, ParallelWork.StartNow(() => { workStartedAt = DateTime.Now; Thread.Sleep(howLongWorkTakes); }, () => { workEndedAt = DateTime.Now; }); Or you can use the fluent way Start.Work: Start.Work(() => { workStartedAt = DateTime.Now; Thread.Sleep(howLongWorkTakes); }) .OnComplete(() => { workCompletedAt = DateTime.Now; }) .Run(); Besides simple execution of work on a parallel thread, you can have the parallel thread produce some object and then pass it to the success callback by using these overloads: void StartNow<T>(Func<T> doWork, Action<T> onComplete) void StartNow<T>(Func<T> doWork, Action<T> onComplete, Action<Exception> fail) For example, ParallelWork.StartNow<Dictionary<string, string>>( () => { test = new Dictionary<string,string>(); test.Add("test", "test"); return test; }, (result) => { Assert.True(result.ContainsKey("test")); }); Or, the fluent way: Start<Dictionary<string, string>>.Work(() => { test = new Dictionary<string, string>(); test.Add("test", "test"); return test; }) .OnComplete((result) => { Assert.True(result.ContainsKey("test")); }) .Run(); You can also start a work to happen after some time using these methods: DispatcherTimer StartAfter(Action onComplete, TimeSpan duration) DispatcherTimer StartAfter(Action doWork,Action onComplete,TimeSpan duration) You can use this to perform some timed operation on the UI thread, as well as perform some operation in separate thread after some time. ParallelWork.StartAfter( () => { workStartedAt = DateTime.Now; Thread.Sleep(howLongWorkTakes); }, () => { workCompletedAt = DateTime.Now; }, waitDuration); Or, the fluent way: Start.Work(() => { workStartedAt = DateTime.Now; Thread.Sleep(howLongWorkTakes); }) .OnComplete(() => { workCompletedAt = DateTime.Now; }) .RunAfter(waitDuration);   There are several overloads of these functions to have a exception callback for handling exceptions or get progress update from background thread while work is in progress. For example, I use it in my PlantUmlEditor to perform background update of the application. // Check if there's a newer version of the app Start<bool>.Work(() => { return UpdateChecker.HasUpdate(Settings.Default.DownloadUrl); }) .OnComplete((hasUpdate) => { if (hasUpdate) { if (MessageBox.Show(Window.GetWindow(me), "There's a newer version available. Do you want to download and install?", "New version available", MessageBoxButton.YesNo, MessageBoxImage.Information) == MessageBoxResult.Yes) { ParallelWork.StartNow(() => { var tempPath = System.IO.Path.Combine( Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData), Settings.Default.SetupExeName); UpdateChecker.DownloadLatestUpdate(Settings.Default.DownloadUrl, tempPath); }, () => { }, (x) => { MessageBox.Show(Window.GetWindow(me), "Download failed. When you run next time, it will try downloading again.", "Download failed", MessageBoxButton.OK, MessageBoxImage.Warning); }); } } }) .OnException((x) => { MessageBox.Show(Window.GetWindow(me), x.Message, "Download failed", MessageBoxButton.OK, MessageBoxImage.Exclamation); }); The above code shows you how to get exception callbacks on the UI thread so that you can take necessary actions on the UI. Moreover, it shows how you can chain two parallel works to happen one after another. Sometimes you want to do some parallel work when user does some activity on the UI. For example, you might want to save file in an editor while user is typing every 10 second. In such case, you need to make sure you don’t start another parallel work every 10 seconds while a work is already queued. You need to make sure you start a new work only when there’s no other background work going on. Here’s how you can do it: private void ContentEditor_TextChanged(object sender, EventArgs e) { if (!ParallelWork.IsAnyWorkRunning()) { ParallelWork.StartAfter(SaveAndRefreshDiagram, TimeSpan.FromSeconds(10)); } } If you want to shutdown your application and want to make sure no parallel work is going on, then you can call the StopAll() method. ParallelWork.StopAll(); If you want to wait for parallel works to complete without a timeout, then you can call the WaitForAllWork(TimeSpan timeout). It will block the current thread until the all parallel work completes or the timeout period elapses. result = ParallelWork.WaitForAllWork(TimeSpan.FromSeconds(1)); The result is true, if all parallel work completed. If it’s false, then the timeout period elapsed and all parallel work did not complete. For details how this library is built and how it works, please read the following codeproject article: ParallelWork: Feature rich multithreaded fluent task execution library for WPF http://www.codeproject.com/KB/WPF/parallelwork.aspx If you like the article, please vote for me.

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• Preserving Permalinks

  - by Daniel Moth

  One of the things that gets me on a rant is websites that break permalinks. If you have posted something somewhere and there is a public URL pointing to it, that URL should never ever return a 404. You are breaking all websites that ever linked to you and you are breaking all search engine links to your content (that others will try and follow). It is a pet peeve of mine. So when I had to move my blog, obviously I would preserve the root URL (www.danielmoth.com/Blog/), but I also wanted to preserve every URL my blog has generated over the years. To be clear, our focus here is on the URL formatting, not the content migration which I'll talk about in my next post. In this post, I'll describe my solution first and then what it solves. 1. The IIS7 Rewrite Module and web.config There are a few ways you can map an old URL to a new one (so when requests to the old URL come in, they get redirected to the new one). The new blog engine I use (dasBlog) has built-in functionality to do that (Scott refers to it here). Instead, the way I chose to address the issue was to use the IIS7 rewrite module. The IIS7 rewrite module allows redirecting URLs based on pattern matching, regular expressions and, of course, hardcoded full URLs for things that don't fall into any pattern. You can configure it visually from IIS Manager using a handy dialog that allows testing patterns against input URLs. Here is what mine looked like after configuring a few rules: To learn more about this technology check out this video, the reference page and this overview blog post; all 3 pages have a collection of related resources at the bottom worth checking out too. All the visual configuration ends up in a web.config file at the root folder of your website. If you are on a shared hosting service, probably the only way you can use the Rewrite Module is by directly editing the web.config file. Next, I'll describe the URLs I had to map and how that manifested itself in the web.config file. What I did was create the rules locally using the GUI, and then took the generated web.config file and uploaded it to my live site. You can view my web.config here. 2. Monthly Archives Observe the difference between the way the two blog engines generate this type of URL Blogger: /Blog/2004_07_01_mothblog_archive.html dasBlog: /Blog/default,month,2004-07.aspx In my web.config file, the rule that deals with this is the one named "monthlyarchive_redirect". 3. Categories Observe the difference between the way the two blog engines generate this type of URL Blogger: /Blog/labels/Personal.html dasBlog: /Blog/CategoryView,category,Personal.aspx In my web.config file the rule that deals with this is the one named "category_redirect". 4. Posts Observe the difference between the way the two blog engines generate this type of URL Blogger: /Blog/2004/07/hello-world.html dasBlog: /Blog/Hello-World.aspx In my web.config file the rule that deals with this is the one named "post_redirect". Note: The decision is taken to use dasBlog URLs that do not include the date info (see the description of my Appearance settings). If we included the date info then it would have to include the day part, which blogger did not generate. This makes it impossible to redirect correctly and to have a single permalink for blog posts moving forward. An implication of this decision, is that no two blog posts can have the same title. The tool I will describe in my next post (inelegantly) deals with duplicates, but not with triplicates or higher. 5. Unhandled by a generic rule Unfortunately, the two blog engines use different rules for generating URLs for blog posts. Most of the time the conversion is as simple as the example of the previous section where a post titled "Hello World" generates a URL with the words separated by a hyphen. Some times that is not the case, for example: /Blog/2006/05/medc-wrap-up.html /Blog/MEDC-Wrapup.aspx or /Blog/2005/01/best-of-moth-2004.html /Blog/Best-Of-The-Moth-2004.aspx or /Blog/2004/11/more-windows-mobile-2005-details.html /Blog/More-Windows-Mobile-2005-Details-Emerge.aspx In short, blogger does not add words to the title beyond ~39 characters, it drops some words from the title generation (e.g. a, an, on, the), and it preserve hyphens that appear in the title. For this reason, we need to detect these and explicitly list them for redirects (no regular expression can help here because the full set of rules is not listed anywhere). In my web.config file the rule that deals with this is the one named "Redirect rule1 for FullRedirects" combined with the rewriteMap named "StaticRedirects". Note: The tool I describe in my next post will detect all the URLs that need to be explicitly redirected and will list them in a file ready for you to copy them to your web.config rewriteMap. 6. C# code doing the same as the web.config I wrote some naive code that does the same thing as the web.config: given a string it will return a new string converted according to the 3 rules above. It does not take into account the 4th case where an explicit hard-coded conversion is needed (the tool I present in the next post does take that into account). static string REGEX_post_redirect = "[0-9]{4}/[0-9]{2}/([0-9a-z-]+).html"; static string REGEX_category_redirect = "labels/([_0-9a-z-% ]+).html"; static string REGEX_monthlyarchive_redirect = "([0-9]{4})_([0-9]{2})_[0-9]{2}_mothblog_archive.html"; static string Redirect(string oldUrl) { GroupCollection g; if (RunRegExOnIt(oldUrl, REGEX_post_redirect, 2, out g)) return string.Concat(g[1].Value, ".aspx"); if (RunRegExOnIt(oldUrl, REGEX_category_redirect, 2, out g)) return string.Concat("CategoryView,category,", g[1].Value, ".aspx"); if (RunRegExOnIt(oldUrl, REGEX_monthlyarchive_redirect, 3, out g)) return string.Concat("default,month,", g[1].Value, "-", g[2], ".aspx"); return string.Empty; } static bool RunRegExOnIt(string toRegEx, string pattern, int groupCount, out GroupCollection g) { if (pattern.Length == 0) { g = null; return false; } g = new Regex(pattern, RegexOptions.IgnoreCase | RegexOptions.Compiled).Match(toRegEx).Groups; return (g.Count == groupCount); } Comments about this post welcome at the original blog.

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• CQRS &ndash; Questions and Concerns

  - by Dylan Smith

  I’ve been doing a lot of learning on CQRS and Event Sourcing over the last little while and I have a number of questions that I haven’t been able to answer. 1. What is the benefit of CQRS when compared to a typical DDD architecture that uses Event Sourcing and properly captures intent and behavior via verb-based commands? (other than Scalability) 2. When using CQRS what do you do with complex query-based logic? I’m going to elaborate on #1 in this blog post and I’ll do a follow-up post on #2. I watched through Greg Young’s video on the business benefits of CQRS + Event Sourcing and first let me say that I thought it was an excellent presentation that really drives home a lot of the benefits to this approach to architecture (I watched it twice in a row I enjoyed it so much!). But it didn’t answer some of my questions fully (I wish I had been there to ask these of Greg in person!). So let me pick apart some of the points he makes and how they relate to my first question above. I’m completely sold on the idea of event sourcing and have a clear understanding of the benefits that it brings to the table, so I’m not going to question that. But you can use event sourcing without going to a CQRS architecture, so my main question is around the benefits of CQRS + Event Sourcing vs Event Sourcing + Typical DDD architecture Architecture with Event Sourcing + Commands on Left, CQRS on Right Greg talks about how the stereotypical architecture doesn’t support DDD, but is that only because his diagram shows DTO’s coming up from the client. If we use the same diagram but allow the client to send commands doesn’t that remove a lot of the arguments that Greg makes against the stereotypical architecture? We can now introduce verbs into the system. We can capture intent now (storing it still requires event sourcing, but you can implement event sourcing without doing CQRS) We can create a rich domain model (as opposed to an anemic domain model) Scalability is obviously a benefit that CQRS brings to the table, but like Greg says, very few of the systems we create truly need significant scalability Greg talks about the ability to scale your development efforts. He says CQRS allows you to split the system into 3 parts (Client, Domain/Commands, Reads) and assign 3 teams of developers to work on them in parallel; letting you scale your development efforts by 3x with nearly linear gains. But in the stereotypical architecture don’t you already have 2 separate modules that you can split your dev efforts between: The client that sends commands/queries and receives DTO’s, and the Domain which accepts commands/queries, and generates events/DTO’s. If this is true it’s not really a 3x scaling you achieve with CQRS but merely a 1.5x scaling which while great doesn’t sound nearly as dramatic (“I can do it with 10 devs in 12 months – let me hire 5 more and we can have it done in 8 months”). Making the Query side “stupid simple” such that you can assign junior developers (or even outsource it) sounds like a valid benefit, but I have some concerns over what you do with complex query-based logic/behavior. I’m going to go into more detail on this in a follow-up blog post shortly. He also seemed to focus on how “stupid-simple” it is doing queries against the de-normalized data store, but I imagine there is still significant complexity in the event handlers that interpret the events and apply them to the de-normalized tables. It sounds like Greg suggests that because we’re doing CQRS that allows us to apply Event Sourcing when we otherwise wouldn’t be able to (~33:30 in the video). I don’t believe this is true. I don’t see why you wouldn’t be able to apply Event Sourcing without separating out the Commands and Queries. The queries would just operate against the domain model instead of the database. But you’d still get the benefits of Event Sourcing. Without CQRS the queries would only be able to operate against the current state rather than the event history, but even in CQRS the domain behaviors can only operate against the current state and I don’t see that being a big limiting factor. If some query needs to operate against something that is not captured by the current state you would just have to update the domain model to capture that information (no different than if that statement were made about a Command under CQRS). Some of the benefits I do see being applicable are that your domain model might end up being simpler/smaller since it only needs to represent the state needed to process commands and not worry about the reads (like the Deactivate Inventory Item and associated comment example that Greg provides). And also commands that can be handled in a Transaction Script style manner by the command handler simply generating events and not touching the domain model. It also makes it easier for your senior developers to focus on the command behavior and ignore the queries, which is usually going to be a better use of their time. And of course scalability. If anybody out there has any thoughts on this and can help educate me further, please either leave a comment or feel free to get in touch with me via email:

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• System locking up with suspicious messages about hard disk

  - by Chris Conway

  My system has started behaving strangely, intermittently locking up. I see messages like the following in syslog: Nov 18 22:22:00 claypool kernel: [ 3428.078156] ata3.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0 Nov 18 22:22:00 claypool kernel: [ 3428.078163] ata3.00: irq_stat 0x40000000 Nov 18 22:22:00 claypool kernel: [ 3428.078167] sr 2:0:0:0: CDB: Test Unit Ready: 00 00 00 00 00 00 Nov 18 22:22:00 claypool kernel: [ 3428.078182] ata3.00: cmd a0/00:00:00:00:00/00:00:00:00:00/a0 tag 0 Nov 18 22:22:00 claypool kernel: [ 3428.078184] res 50/00:03:00:00:00/00:00:00:00:00/a0 Emask 0x1 (device error) Nov 18 22:22:00 claypool kernel: [ 3428.078188] ata3.00: status: { DRDY } Nov 18 22:22:00 claypool kernel: [ 3428.080887] ata3.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0 Nov 18 22:22:00 claypool kernel: [ 3428.080890] ata3.00: irq_stat 0x40000000 Nov 18 22:22:00 claypool kernel: [ 3428.080893] sr 2:0:0:0: CDB: Test Unit Ready: 00 00 00 00 00 00 Nov 18 22:22:00 claypool kernel: [ 3428.080905] ata3.00: cmd a0/00:00:00:00:00/00:00:00:00:00/a0 tag 0 Nov 18 22:22:00 claypool kernel: [ 3428.080906] res 50/00:03:00:00:00/00:00:00:00:00/a0 Emask 0x1 (device error) Nov 18 22:22:00 claypool kernel: [ 3428.080910] ata3.00: status: { DRDY } And then this: Nov 18 23:13:56 claypool kernel: [ 6544.000798] ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x6 frozen Nov 18 23:13:56 claypool kernel: [ 6544.000804] ata1.00: failed command: FLUSH CACHE EXT Nov 18 23:13:56 claypool kernel: [ 6544.000814] ata1.00: cmd ea/00:00:00:00:00/00:00:00:00:00/a0 tag 0 Nov 18 23:13:56 claypool kernel: [ 6544.000815] res 40/00:00:00:4f:c2/00:00:00:00:00/40 Emask 0x4 (timeout) Nov 18 23:13:56 claypool kernel: [ 6544.000819] ata1.00: status: { DRDY } Nov 18 23:13:56 claypool kernel: [ 6544.000825] ata1: hard resetting link Nov 18 23:14:01 claypool kernel: [ 6549.360324] ata1: link is slow to respond, please be patient (ready=0) Nov 18 23:14:06 claypool kernel: [ 6554.008091] ata1: COMRESET failed (errno=-16) Nov 18 23:14:06 claypool kernel: [ 6554.008103] ata1: hard resetting link Nov 18 23:14:11 claypool kernel: [ 6559.372246] ata1: link is slow to respond, please be patient (ready=0) Nov 18 23:14:16 claypool kernel: [ 6564.020228] ata1: COMRESET failed (errno=-16) Nov 18 23:14:16 claypool kernel: [ 6564.020235] ata1: hard resetting link Nov 18 23:14:21 claypool kernel: [ 6569.380109] ata1: link is slow to respond, please be patient (ready=0) Nov 18 23:14:31 claypool kernel: [ 6579.460243] ata1: SATA link up 3.0 Gbps (SStatus 123 SControl 300) Nov 18 23:14:31 claypool kernel: [ 6579.486595] ata1.00: configured for UDMA/133 Nov 18 23:14:31 claypool kernel: [ 6579.486601] ata1.00: retrying FLUSH 0xea Emask 0x4 Nov 18 23:14:31 claypool kernel: [ 6579.486939] ata1.00: device reported invalid CHS sector 0 Nov 18 23:14:31 claypool kernel: [ 6579.486952] ata1: EH complete Nov 18 23:17:01 claypool CRON[3910]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly) Nov 18 23:17:01 claypool CRON[3908]: (CRON) error (grandchild #3910 failed with exit status 1) Nov 18 23:17:01 claypool postfix/sendmail[3925]: fatal: open /etc/postfix/main.cf: No such file or directory Nov 18 23:17:01 claypool CRON[3908]: (root) MAIL (mailed 1 byte of output; but got status 0x004b, #012) Nov 18 23:39:01 claypool CRON[4200]: (root) CMD ( [ -x /usr/lib/php5/maxlifetime ] && [ -d /var/lib/php5 ] && find /var/lib/php5/ -type f -cmin +$(/usr/lib/php5/maxlifetime) -print0 | xargs -n 200 -r -0 rm) There are no messages marked after 23:39. When I next tried to use the machine, it would not return from the screensaver (blank screen), nor switch to another terminal, and I had to hard reboot it. [UPDATE] The output of smartctl is here. I had trouble getting this, because / is being mounted read-only (?!), which prevents most applications from running. Also, it may not be related, but I have the following worrying messages in dmesg: [ 10.084596] k8temp 0000:00:18.3: Temperature readouts might be wrong - check erratum #141 [ 10.098477] i2c i2c-0: nForce2 SMBus adapter at 0x600 [ 10.098483] ACPI: resource nForce2_smbus [io 0x0700-0x073f] conflicts with ACPI region SM00 [??? 0x00000700-0x0000073f flags 0x30] [ 10.098486] ACPI: This conflict may cause random problems and system instability [ 10.098487] ACPI: If an ACPI driver is available for this device, you should use it instead of the native driver [ 10.098509] i2c i2c-1: nForce2 SMBus adapter at 0x700 [ 10.112570] Linux agpgart interface v0.103 [ 10.155329] atk: Resources not safely usable due to acpi_enforce_resources kernel parameter [ 10.161506] it87: Found IT8712F chip at 0x290, revision 8 [ 10.161517] it87: VID is disabled (pins used for GPIO) [ 10.161527] it87: in3 is VCC (+5V) [ 10.161528] it87: in7 is VCCH (+5V Stand-By) [ 10.161560] ACPI: resource it87 [io 0x0295-0x0296] conflicts with ACPI region ECRE [??? 0x00000290-0x000002af flags 0x45] [ 10.161562] ACPI: This conflict may cause random problems and system instability [ 10.161564] ACPI: If an ACPI driver is available for this device, you should use it instead of the native driver [UPDATE 2] I swapped in a new SATA cable, per Phil's suggestion. The current output of smartctl is here, if it helps. [UPDATE 3] I don't think the cable fixed it. The system hasn't locked up yet, but my media player crashed a few minutes ago and I have the following in the syslog: Nov 20 16:07:17 claypool kernel: [ 2294.400033] ata1: link is slow to respond, please be patient (ready=0) Nov 20 16:07:47 claypool kernel: [ 2324.084581] ata1: COMRESET failed (errno=-16) Nov 20 16:07:47 claypool kernel: [ 2324.084588] ata1: limiting SATA link speed to 1.5 Gbps Nov 20 16:07:47 claypool kernel: [ 2324.084592] ata1: hard resetting link I get the following response from smartctl: $ sudo smartctl -a /dev/sda [sudo] password for chris: sudo: Can't open /var/lib/sudo/chris/0: Read-only file system smartctl 5.40 2010-03-16 r3077 [i686-pc-linux-gnu] (local build) Copyright (C) 2002-10 by Bruce Allen, http://smartmontools.sourceforge.net Device: /0:0:0:0 Version: scsiModePageOffset: response length too short, resp_len=47 offset=50 bd_len=46 >> Terminate command early due to bad response to IEC mode page A mandatory SMART command failed: exiting. To continue, add one or more '-T permissive' options.

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• Agile Testing Days 2012 – Day 1 – The birth of the #unicorn…

  - by Chris George

  Still riding the high from the tutorial day, I arrived at the conference venue eager to get cracking with the days talks. The opening Keynote was “Disciplined Agile Delivery: The Foundation for Scaling Agile” presented by Scott Ambler. The general ideas behind the methodology such as not re-inventing the wheel, and being goal driven, not prescriptive in how you work certainly struck chords with how we are trying to work in my team. Scott made some interesting observations about how scrum is quite prescriptive and is this really agile? I agreed with quite a few of his points on how what works for one team may not work for another. How a team works should be driven by context and reflection, not process and prescription. However was somewhat dubious about some of the statistics he rolled out towards the end. However, out of this keynote was born something that was to transcend this one presentation. During the talk, Scott mentioned on more than one occasion “In the real world”, and at one point made reference to people living in the land of unicorns and rainbows. The challenge was then laid down on twitter for all speakers to include a unicorn in their presentations… and for the most part this happened! It became an identity for this years conference, and I’m sure something that any attendee will always associate with Agile Testing Days 2012! Following this keynote, I attended “Going agile with Automated GUI Testing – Some personal insights” by Jan Zdunek from codecentric on the vendor track. My speciality is test automation, and in particular GUI testing, so this drew me to this talk more than the others. Thankfully, it was made clear from the very start that this was not peddling any particular product (even though it was on the vendor track), and Jan faithfully stuck to that. Most of the content was not new to me, but it was really comforting to hear someone else with very similar experiences to my own. In particular, things like how GUI testing is hard and is not a silver bullet; how record & replay is NOT a good thing to do (which drew a somewhat inflammatory tweet from an automation company when I tweeted that!). Something that I have started hearing around the place, and has certainly been murmuring at work is to push more of the automation coding onto the developers. After all they are the coding experts. I agree with this to a degree, but I personally enjoy coding and find it very rewarding doing so, therefore I’d be reluctant to give it up. I think there are some better alternatives such as pairing with a developer. Lastly, Jan mentioned, almost in passing, that we should consider virtualisation for gui testing for covering configuration combinations. On my project we’ve been running our win32/.NET GUI tests in cloud virtualisation for a couple of years now… I really should write about that! After lunch the second keynote of the day was by Lisa Crispin and Janet Gregory,”Myths about Agile Testing, De-Bunked”. It started off well… with the two ladies donning Medusa style head bands whilst they disbanding several myths about agile testing! I got the impression that it was perhaps not as slick as they would have liked, but then Janet was suffering with a very sore throat so kept losing her voice. Nevertheless, the presentation was captivating, and they debunked several myths such as : “Testing is dead”, “Testers must write code”, “Agile teams always deliver faster”. I didn’t take many notes for this because it was being recorded, but unfortunately the recordings have not been posted yet so I’ll write more about this when they are. The TestLab was held during a somewhat free for all time during most of the afternoon. It looked intriguing and proved to be one of the surprising experiences of the conference for me. Run by James Lyndsay and Bart Knaack, it consisted of a number of ‘stations’ that offered different testing problems. I opted for testing a mathematical drawing app call Geogebra, the task being to pair up and exploratory test it. After an allotted time, we discussed issues we’d found and decided if we wanted to continue ‘playing’ to which we all agreed! It was fun! The last track talk of the day was “Developers Exploratory Testing – Raising the bar” by Sigge Birgisson. One of the teams at Red Gate have tried Dev or Team exploratory testing a couple of times, and I was really interested to go to the presentation that prompted that. I was not disappointed! Sigge gave a first class presentation, and not only explained what DET was all about, but also how to go about implementing it. Little tips like calling it a ‘workshop’ rather than ‘testing’ I can really see working! Monday evening saw the presentation of the award for the Most Influential Agile Testing Professional Person go to a much deserved Lisa Crispin. The evening was great, with acrobatics, magic and music. My Takeaway Triple from Day 1:  Some of the cool stuff that was suggested in the GUI Testing talk, we are already doing. I should write about that! Testing is not dead! Perhaps testing will become more of a skill than a specific role, but it is certainly not dead. Team/Developer exploratory testing… seems like a no-brainer assuming you have a team who is willing.  Day 2 – Coming soon…

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• RequestValidation Changes in ASP.NET 4.0

  - by Rick Strahl

  There’s been a change in the way the ValidateRequest attribute on WebForms works in ASP.NET 4.0. I noticed this today while updating a post on my WebLog all of which contain raw HTML and so all pretty much trigger request validation. I recently upgraded this app from ASP.NET 2.0 to 4.0 and it’s now failing to update posts. At first this was difficult to track down because of custom error handling in my app – the custom error handler traps the exception and logs it with only basic error information so the full detail of the error was initially hidden. After some more experimentation in development mode the error that occurs is the typical ASP.NET validate request error (‘A potentially dangerous Request.Form value was detetected…’) which looks like this in ASP.NET 4.0: At first when I got this I was real perplexed as I didn’t read the entire error message and because my page does have: <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="NewEntry.aspx.cs" Inherits="Westwind.WebLog.NewEntry" MasterPageFile="~/App_Templates/Standard/AdminMaster.master" ValidateRequest="false" EnableEventValidation="false" EnableViewState="false" %> WTF? ValidateRequest would seem like it should be enough, but alas in ASP.NET 4.0 apparently that setting alone is no longer enough. Reading the fine print in the error explains that you need to explicitly set the requestValidationMode for the application back to V2.0 in web.config: <httpRuntime executionTimeout="300" requestValidationMode="2.0" /> Kudos for the ASP.NET team for putting up a nice error message that tells me how to fix this problem, but excuse me why the heck would you change this behavior to require an explicit override to an optional and by default disabled page level switch? You’ve just made a relatively simple fix to a solution a nasty morass of hard to discover configuration settings??? The original way this worked was perfectly discoverable via attributes in the page. Now you can set this setting in the page and get completely unexpected behavior and you are required to set what effectively amounts to a backwards compatibility flag in the configuration file. It turns out the real reason for the .config flag is that the request validation behavior has moved from WebForms pipeline down into the entire ASP.NET/IIS request pipeline and is now applied against all requests. Here’s what the breaking changes page from Microsoft says about it: The request validation feature in ASP.NET provides a certain level of default protection against cross-site scripting (XSS) attacks. In previous versions of ASP.NET, request validation was enabled by default. However, it applied only to ASP.NET pages (.aspx files and their class files) and only when those pages were executing. In ASP.NET 4, by default, request validation is enabled for all requests, because it is enabled before the BeginRequest phase of an HTTP request. As a result, request validation applies to requests for all ASP.NET resources, not just .aspx page requests. This includes requests such as Web service calls and custom HTTP handlers. Request validation is also active when custom HTTP modules are reading the contents of an HTTP request. As a result, request validation errors might now occur for requests that previously did not trigger errors. To revert to the behavior of the ASP.NET 2.0 request validation feature, add the following setting in the Web.config file: <httpRuntime requestValidationMode="2.0" /> However, we recommend that you analyze any request validation errors to determine whether existing handlers, modules, or other custom code accesses potentially unsafe HTTP inputs that could be XSS attack vectors. Ok, so ValidateRequest of the form still works as it always has but it’s actually the ASP.NET Event Pipeline, not WebForms that’s throwing the above exception as request validation is applied to every request that hits the pipeline. Creating the runtime override removes the HttpRuntime checking and restores the WebForms only behavior. That fixes my immediate problem but still leaves me wondering especially given the vague wording of the above explanation. One thing that’s missing in the description is above is one important detail: The request validation is applied only to application/x-www-form-urlencoded POST content not to all inbound POST data. When I first read this this freaked me out because it sounds like literally ANY request hitting the pipeline is affected. To make sure this is not really so I created a quick handler: public class Handler1 : IHttpHandler { public void ProcessRequest(HttpContext context) { context.Response.ContentType = "text/plain"; context.Response.Write("Hello World <hr>" + context.Request.Form.ToString()); } public bool IsReusable { get { return false; } } } and called it with Fiddler by posting some XML to the handler using a default form-urlencoded POST content type: and sure enough – hitting the handler also causes the request validation error and 500 server response. Changing the content type to text/xml effectively fixes the problem however, bypassing the request validation filter so Web Services/AJAX handlers and custom modules/handlers that implement custom protocols aren’t affected as long as they work with special input content types. It also looks that multipart encoding does not trigger event validation of the runtime either so this request also works fine: POST http://rasnote/weblog/handler1.ashx HTTP/1.1 Content-Type: multipart/form-data; boundary=------7cf2a327f01ae User-Agent: West Wind Internet Protocols 5.53 Host: rasnote Content-Length: 40 Pragma: no-cache <xml>asdasd</xml>--------7cf2a327f01ae *That* probably should trigger event validation – since it is a potential HTML form submission, but it doesn’t. New Runtime Feature, Global Scope Only? Ok, so request validation is now a runtime feature but sadly it’s a feature that’s scoped to the ASP.NET Runtime – effective scope to the entire running application/app domain. You can still manually force validation using Request.ValidateInput() which gives you the option to do this in code, but that realistically will only work with the requestValidationMode set to V2.0 as well since the 4.0 mode auto-fires before code ever gets a chance to intercept the call. Given all that, the new setting in ASP.NET 4.0 seems to limit options and makes things more difficult and less flexible. Of course Microsoft gets to say ASP.NET is more secure by default because of it but what good is that if you have to turn off this flag the very first time you need to allow one single request that bypasses request validation??? This is really shortsighted design… <sigh>© Rick Strahl, West Wind Technologies, 2005-2010Posted in ASP.NET  

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• Using the Static Code Analysis feature of Visual Studio (Premium/Ultimate) to find memory leakage problems

  - by terje

  Memory for managed code is handled by the garbage collector, but if you use any kind of unmanaged code, like native resources of any kind, open files, streams and window handles, your application may leak memory if these are not properly handled.  To handle such resources the classes that own these in your application should implement the IDisposable interface, and preferably implement it according to the pattern described for that interface. When you suspect a memory leak, the immediate impulse would be to start up a memory profiler and start digging into that.   However, before you follow that impulse, do a Static Code Analysis run with a ruleset tuned to finding possible memory leaks in your code.  If you get any warnings from this, fix them before you go on with the profiling. How to use a ruleset In Visual Studio 2010 (Premium and Ultimate editions) you can define your own rulesets containing a list of Static Code Analysis checks.   I have defined the memory checks as shown in the lists below as ruleset files, which can be downloaded – see bottom of this post.  When you get them, you can easily attach them to every project in your solution using the Solution Properties dialog. Right click the solution, and choose Properties at the bottom, or use the Analyze menu and choose “Configure Code Analysis for Solution”: In this dialog you can now choose the Memorycheck ruleset for every project you want to investigate.  Pressing Apply or Ok opens every project file and changes the projects code analysis ruleset to the one we have specified here. How to define your own ruleset  (skip this if you just download my predefined rulesets) If you want to define the ruleset yourself, open the properties on any project, choose Code Analysis tab near the bottom, choose any ruleset in the drop box and press Open Clear out all the rules by selecting “Source Rule Sets” in the Group By box, and unselect the box Change the Group By box to ID, and select the checks you want to include from the lists below. Note that you can change the action for each check to either warning, error or none, none being the same as unchecking the check.   Now go to the properties window and set a new name and description for your ruleset. Then save (File/Save as) the ruleset using the new name as its name, and use it for your projects as detailed above. It can also be wise to add the ruleset to your solution as a solution item. That way it’s there if you want to enable Code Analysis in some of your TFS builds.   Running the code analysis In Visual Studio 2010 you can either do your code analysis project by project using the context menu in the solution explorer and choose “Run Code Analysis”, you can define a new solution configuration, call it for example Debug (Code Analysis), in for each project here enable the Enable Code Analysis on Build   In Visual Studio Dev-11 it is all much simpler, just go to the Solution root in the Solution explorer, right click and choose “Run code analysis on solution”.     The ruleset checks The following list is the essential and critical memory checks.  CheckID Message Can be ignored ? Link to description with fix suggestions CA1001 Types that own disposable fields should be disposable No  http://msdn.microsoft.com/en-us/library/ms182172.aspx CA1049 Types that own native resources should be disposable Only if the pointers assumed to point to unmanaged resources point to something else  http://msdn.microsoft.com/en-us/library/ms182173.aspx CA1063 Implement IDisposable correctly No  http://msdn.microsoft.com/en-us/library/ms244737.aspx CA2000 Dispose objects before losing scope No  http://msdn.microsoft.com/en-us/library/ms182289.aspx CA2115 1 Call GC.KeepAlive when using native resources See description  http://msdn.microsoft.com/en-us/library/ms182300.aspx CA2213 Disposable fields should be disposed If you are not responsible for release, of if Dispose occurs at deeper level  http://msdn.microsoft.com/en-us/library/ms182328.aspx CA2215 Dispose methods should call base class dispose Only if call to base happens at deeper calling level  http://msdn.microsoft.com/en-us/library/ms182330.aspx CA2216 Disposable types should declare a finalizer Only if type does not implement IDisposable for the purpose of releasing unmanaged resources  http://msdn.microsoft.com/en-us/library/ms182329.aspx CA2220 Finalizers should call base class finalizers No  http://msdn.microsoft.com/en-us/library/ms182341.aspx Notes: 1) Does not result in memory leak, but may cause the application to crash   The list below is a set of optional checks that may be enabled for your ruleset, because the issues these points too often happen as a result of attempting to fix up the warnings from the first set.   ID Message Type of fault Can be ignored ? Link to description with fix suggestions CA1060 Move P/invokes to NativeMethods class Security No http://msdn.microsoft.com/en-us/library/ms182161.aspx CA1816 Call GC.SuppressFinalize correctly Performance Sometimes, see description http://msdn.microsoft.com/en-us/library/ms182269.aspx CA1821 Remove empty finalizers Performance No http://msdn.microsoft.com/en-us/library/bb264476.aspx CA2004 Remove calls to GC.KeepAlive Performance and maintainability Only if not technically correct to convert to SafeHandle http://msdn.microsoft.com/en-us/library/ms182293.aspx CA2006 Use SafeHandle to encapsulate native resources Security No http://msdn.microsoft.com/en-us/library/ms182294.aspx CA2202 Do not dispose of objects multiple times Exception (System.ObjectDisposedException) No http://msdn.microsoft.com/en-us/library/ms182334.aspx CA2205 Use managed equivalents of Win32 API Maintainability and complexity Only if the replace doesn’t provide needed functionality http://msdn.microsoft.com/en-us/library/ms182365.aspx CA2221 Finalizers should be protected Incorrect implementation, only possible in MSIL coding No http://msdn.microsoft.com/en-us/library/ms182340.aspx   Downloadable ruleset definitions I have defined three rulesets, one called Inmeta.Memorycheck with the rules in the first list above, and Inmeta.Memorycheck.Optionals containing the rules in the second list, and the last one called Inmeta.Memorycheck.All containing the sum of the two first ones.  All three rulesets can be found in the  zip archive  “Inmeta.Memorycheck” downloadable from here.   Links to some other resources relevant to Static Code Analysis MSDN Magazine Article by Mickey Gousset on Static Code Analysis in VS2010 MSDN :  Analyzing Managed Code Quality by Using Code Analysis, root of the documentation for this Preventing generated code from being analyzed using attributes Online training course on Using Code Analysis with VS2010 Blogpost by Tatham Oddie on custom code analysis rules How to write custom rules, from Microsoft Code Analysis Team Blog Microsoft Code Analysis Team Blog

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• Do You Develop Your PL/SQL Directly in the Database?

  - by thatjeffsmith

  I know this sounds like a REALLY weird question for many of you. Let me make one thing clear right away though, I am NOT talking about creating and replacing PLSQL objects directly into a production environment. Do we really need to talk about developers in production again? No, what I am talking about is a developer doing their work from start to finish in a development database. These are generally available to a development team for building the next and greatest version of your databases and database applications. And of course you are using a third party source control system, right? Last week I was in Tampa, FL presenting at the monthly Suncoast Oracle User’s Group meeting. Had a wonderful time, great questions and back-and-forth. My favorite heckler was there, @oraclenered, AKA Chet Justice.  I was in the middle of talking about how it’s better to do your PLSQL work in the Procedure Editor when Chet pipes up - Don’t do it that way, that’s wrong Just press play to edit the PLSQL directly in the database Or something along those lines. I didn’t get what the heck he was talking about. I had been showing how the Procedure Editor gives you much better feedback and support when working with PLSQL. After a few back-and-forths I got to what Chet’s main objection was, and again I’m going to paraphrase: You should develop offline in your SQL worksheet. Don’t do anything in the database until it’s done. I didn’t understand. Were developers expected to be able to internalize and mentally model the PL/SQL engine, see where their errors were, etc in these offline scripts? No, please give Chet more credit than that. What is the ideal Oracle Development Environment? If I were back in the ‘real world’ of database development, I would do all of my development outside of the ‘dev’ instance. My development process looks a little something like this: Do I have a program that already does something like this – copy and paste Has some smart person already written something like this – copy and paste Start typing in the white-screen-of-panic and bungle along until I get something that half-works Tweek, debug, test until I have fooled my subconscious into thinking that it’s ‘good’ As you might understand, I don’t want my co-workers to see the evolution of my code. It would seriously freak them out and I probably wouldn’t have a job anymore (don’t remind me that I already worked myself out of development.) So here’s what I like to do: Run a Local Instance of Oracle on my Machine and Develop My Code Privately I take a copy of development – that’s what source control is for afterall – and run it where no one else can see it. I now get to be my own DBA. If I need a trace – no problem. If I want to run an ASH report, no worries. If I need to create a directory or run some DataPump jobs, that’s all on me. Now when I get my code ‘up to snuff,’ then I will check it into source control and compile it into the official development instance. So my teammates suddenly go from seeing no program, to a mostly complete program. Is this right? If not, it doesn’t seem wrong to me. And after talking to Chet in the car on the way to the local cigar bar, it seems that he’s of the same opinion. So what’s so wrong with coding directly into a development instance? I think ‘wrong’ is a bit strong here. But there are a few pitfalls that you might want to look out for. A few come to mind – and I’m sure Chet could add many more as my memory fails me at the moment. But here goes: Development instance isn’t properly backed up – would hate to lose that work Development is wiped once a week and copied over from Prod – don’t laugh Someone clobbers your code You accidentally on purpose clobber someone else’s code The more developers you have in a single fish pond, the greater chance something ‘bad’ will happen This Isn’t One of Those Posts Where I Tell You What You Should Be Doing I realize many shops won’t be open to allowing developers to stage their own local copies of Oracle. But I would at least be aware that many of your developers are probably doing this anyway – with or without your tacit approval. SQL Developer can do local file tracking, but you should be using Source Control too! I will say that I think it’s imperative that you control your source code outside the database, even if your development team is comprised of a single developer. Store your source code in a file, and control that file in something like Subversion. You would be shocked at the number of teams that do not use a source control system. I know I continue to be shocked no matter how many times I meet another team running by the seat-of-their-pants. I’d love to hear how your development process works. And of course I want to know how SQL Developer and the rest of our tools can better support your processes. And one last thing, if you want a fun and interactive presentation experience, be sure to have Chet in the room

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• Cannot SSH to ubuntu server - openssh server owner changed

  - by Kshitiz Shankar

  I am using suPHP with Apache for virtual hosting but somewhere down the line my root ssh access is getting screwed up. I haven't been able to figure out why it is happening but eventually, my root user is not able to ssh to the server. I get this error: *** invalid open call: O_CREAT without mode ***: sshd: root@pts/3 terminated ======= Backtrace: ========= /lib/x86_64-linux-gnu/libc.so.6(__fortify_fail+0x37)[0x7f12fe871817] /lib/x86_64-linux-gnu/libc.so.6(+0xeb7e1)[0x7f12fe8527e1] sshd: root@pts/3[0x41a542] sshd: root@pts/3[0x41a9eb] sshd: root@pts/3[0x41aeb8] sshd: root@pts/3[0x409630] sshd: root@pts/3[0x40f9ed] sshd: root@pts/3[0x410dd6] sshd: root@pts/3[0x411994] sshd: root@pts/3[0x411f16] sshd: root@pts/3[0x40b253] sshd: root@pts/3[0x42be24] sshd: root@pts/3[0x40c9cb] sshd: root@pts/3[0x412199] sshd: root@pts/3[0x4061a2] /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xed)[0x7f12fe78876d] sshd: root@pts/3[0x407635] ======= Memory map: ======== 00400000-00448000 r-xp 00000000 ca:02 4554758 /usr/sbin/sshd 00647000-00648000 r--p 00047000 ca:02 4554758 /usr/sbin/sshd 00648000-00649000 rw-p 00048000 ca:02 4554758 /usr/sbin/sshd 00649000-00750000 rw-p 00000000 00:00 0 01794000-017b5000 rw-p 00000000 00:00 0 [heap] 7f12fd5ad000-7f12fd5c2000 r-xp 00000000 ca:02 3489844 /lib/x86_64-linux-gnu/libgcc_s.so.1 7f12fd5c2000-7f12fd7c1000 ---p 00015000 ca:02 3489844 /lib/x86_64-linux-gnu/libgcc_s.so.1 7f12fd7c1000-7f12fd7c2000 r--p 00014000 ca:02 3489844 /lib/x86_64-linux-gnu/libgcc_s.so.1 7f12fd7c2000-7f12fd7c3000 rw-p 00015000 ca:02 3489844 /lib/x86_64-linux-gnu/libgcc_s.so.1 7f12fd7c3000-7f12fd7db000 r-xp 00000000 ca:02 3489977 /lib/x86_64-linux-gnu/libresolv-2.15.so 7f12fd7db000-7f12fd9db000 ---p 00018000 ca:02 3489977 /lib/x86_64-linux-gnu/libresolv-2.15.so 7f12fd9db000-7f12fd9dc000 r--p 00018000 ca:02 3489977 /lib/x86_64-linux-gnu/libresolv-2.15.so 7f12fd9dc000-7f12fd9dd000 rw-p 00019000 ca:02 3489977 /lib/x86_64-linux-gnu/libresolv-2.15.so 7f12fd9dd000-7f12fd9df000 rw-p 00000000 00:00 0 7f12fd9df000-7f12fd9e6000 r-xp 00000000 ca:02 3489994 /lib/x86_64-linux-gnu/libnss_dns-2.15.so 7f12fd9e6000-7f12fdbe5000 ---p 00007000 ca:02 3489994 /lib/x86_64-linux-gnu/libnss_dns-2.15.so 7f12fdbe5000-7f12fdbe6000 r--p 00006000 ca:02 3489994 /lib/x86_64-linux-gnu/libnss_dns-2.15.so 7f12fdbe6000-7f12fdbe7000 rw-p 00007000 ca:02 3489994 /lib/x86_64-linux-gnu/libnss_dns-2.15.so 7f12fdbe7000-7f12fdd27000 rw-s 00000000 00:04 6167294 /dev/zero (deleted) 7f12fdd27000-7f12fdd33000 r-xp 00000000 ca:02 3489984 /lib/x86_64-linux-gnu/libnss_files-2.15.so 7f12fdd33000-7f12fdf32000 ---p 0000c000 ca:02 3489984 /lib/x86_64-linux-gnu/libnss_files-2.15.so 7f12fdf32000-7f12fdf33000 r--p 0000b000 ca:02 3489984 /lib/x86_64-linux-gnu/libnss_files-2.15.so 7f12fdf33000-7f12fdf34000 rw-p 0000c000 ca:02 3489984 /lib/x86_64-linux-gnu/libnss_files-2.15.so 7f12fdf34000-7f12fdf3e000 r-xp 00000000 ca:02 3489979 /lib/x86_64-linux-gnu/libnss_nis-2.15.so 7f12fdf3e000-7f12fe13e000 ---p 0000a000 ca:02 3489979 /lib/x86_64-linux-gnu/libnss_nis-2.15.so 7f12fe13e000-7f12fe13f000 r--p 0000a000 ca:02 3489979 /lib/x86_64-linux-gnu/libnss_nis-2.15.so 7f12fe13f000-7f12fe140000 rw-p 0000b000 ca:02 3489979 /lib/x86_64-linux-gnu/libnss_nis-2.15.so 7f12fe140000-7f12fe157000 r-xp 00000000 ca:02 3489996 /lib/x86_64-linux-gnu/libnsl-2.15.so 7f12fe157000-7f12fe356000 ---p 00017000 ca:02 3489996 /lib/x86_64-linux-gnu/libnsl-2.15.so 7f12fe356000-7f12fe357000 r--p 00016000 ca:02 3489996 /lib/x86_64-linux-gnu/libnsl-2.15.so 7f12fe357000-7f12fe358000 rw-p 00017000 ca:02 3489996 /lib/x86_64-linux-gnu/libnsl-2.15.so 7f12fe358000-7f12fe35a000 rw-p 00000000 00:00 0 7f12fe35a000-7f12fe362000 r-xp 00000000 ca:02 3489985 /lib/x86_64-linux-gnu/libnss_compat-2.15.so 7f12fe362000-7f12fe561000 ---p 00008000 ca:02 3489985 /lib/x86_64-linux-gnu/libnss_compat-2.15.so 7f12fe561000-7f12fe562000 r--p 00007000 ca:02 3489985 /lib/x86_64-linux-gnu/libnss_compat-2.15.so 7f12fe562000-7f12fe563000 rw-p 00008000 ca:02 3489985 /lib/x86_64-linux-gnu/libnss_compat-2.15.so 7f12fe563000-7f12fe565000 r-xp 00000000 ca:02 3489886 /lib/x86_64-linux-gnu/libdl-2.15.so 7f12fe565000-7f12fe765000 ---p 00002000 ca:02 3489886 /lib/x86_64-linux-gnu/libdl-2.15.so 7f12fe765000-7f12fe766000 r--p 00002000 ca:02 3489886 /lib/x86_64-linux-gnu/libdl-2.15.so 7f12fe766000-7f12fe767000 rw-p 00003000 ca:02 3489886 /lib/x86_64-linux-gnu/libdl-2.15.so 7f12fe767000-7f12fe91c000 r-xp 00000000 ca:02 3489888 /lib/x86_64-linux-gnu/libc-2.15.so 7f12fe91c000-7f12feb1b000 ---p 001b5000 ca:02 3489888 /lib/x86_64-linux-gnu/libc-2.15.so 7f12feb1b000-7f12feb1f000 r--p 001b4000 ca:02 3489888 /lib/x86_64-linux-gnu/libc-2.15.so 7f12feb1f000-7f12feb21000 rw-p 001b8000 ca:02 3489888 /lib/x86_64-linux-gnu/libc-2.15.so 7f12feb21000-7f12feb26000 rw-p 00000000 00:00 0 7f12feb26000-7f12feb2f000 r-xp 00000000 ca:02 3489983 /lib/x86_64-linux-gnu/libcrypt-2.15.so 7f12feb2f000-7f12fed2f000 ---p 00009000 ca:02 3489983 /lib/x86_64-linux-gnu/libcrypt-2.15.so 7f12fed2f000-7f12fed30000 r--p 00009000 ca:02 3489983 /lib/x86_64-linux-gnu/libcrypt-2.15.so 7f12fed30000-7f12fed31000 rw-p 0000a000 ca:02 3489983 /lib/x86_64-linux-gnu/libcrypt-2.15.so 7f12fed31000-7f12fed5f000 rw-p 00000000 00:00 0 7f12fed5f000-7f12fef10000 r-xp 00000000 ca:02 3489831 /lib/x86_64-linux-gnu/libcrypto.so.1.0.0 7f12fef10000-7f12ff110000 ---p 001b1000 ca:02 3489831 /lib/x86_64-linux-gnu/libcrypto.so.1.0.0 7f12ff110000-7f12ff12b000 r--p 001b1000 ca:02 3489831 /lib/x86_64-linux-gnu/libcrypto.so.1.0.0 7f12ff12b000-7f12ff136000 rw-p 001cc000 ca:02 3489831 /lib/x86_64-linux-gnu/libcrypto.so.1.0.0 7f12ff136000-7f12ff13a000 rw-p 00000000 00:00 0 7f12ff13a000-7f12ff150000 r-xp 00000000 ca:02 3490020 /lib/x86_64-linux-gnu/libz.so.1.2.3.4 7f12ff150000-7f12ff34f000 ---p 00016000 ca:02 3490020 /lib/x86_64-linux-gnu/libz.so.1.2.3.4 7f12ff34f000-7f12ff350000 r--p 00015000 ca:02 3490020 /lib/x86_64-linux-gnu/libz.so.1.2.3.4Connection to stageserver.dockphp.com closed. After some debugging, I was able to narrow it down to a few things. For some reason the sshd daemon is running as root:www-data (apache user) instead of root. My ftp connection works but ssh over terminal fails. I have no idea whether it is getting caused due to suPHP or not (because that is the only place where user permission's etc. change). I really need to narrow it down and fix it asap. Thanks a lot!

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• Parallel LINQ - PLINQ

  - by nmarun

  Turns out now with .net 4.0 we can run a query like a multi-threaded application. Say you want to query a collection of objects and return only those that meet certain conditions. Until now, we basically had one ‘control’ that iterated over all the objects in the collection, checked the condition on each object and returned if it passed. We obviously agree that if we can ‘break’ this task into smaller ones, assign each task to a different ‘control’ and ask all the controls to do their job - in-parallel, the time taken the finish the entire task will be much lower. Welcome to PLINQ. Let’s take some examples. I have the following method that uses our good ol’ LINQ. 1: private static void Linq(int lowerLimit, int upperLimit) 2: { 3: // populate an array with int values from lowerLimit to the upperLimit 4: var source = Enumerable.Range(lowerLimit, upperLimit); 5:  6: // Start a timer 7: Stopwatch stopwatch = new Stopwatch(); 8: stopwatch.Start(); 9:  10: // set the expectation => build the expression tree 11: var evenNumbers =   from num in source 12: where IsDivisibleBy(num, 2) 13: select num; 14: 15: // iterate over and print the returned items 16: foreach (var number in evenNumbers) 17: { 18: Console.WriteLine(string.Format("** {0}", number)); 19: } 20:  21: stopwatch.Stop(); 22:  23: // check the metrics 24: Console.WriteLine(String.Format("Elapsed {0}ms", stopwatch.ElapsedMilliseconds)); 25: } I’ve added comments for the major steps, but the only thing I want to talk about here is the IsDivisibleBy() method. I know I could have just included the logic directly in the where clause. I called a method to add ‘delay’ to the execution of the query - to simulate a loooooooooong operation (will be easier to compare the results). 1: private static bool IsDivisibleBy(int number, int divisor) 2: { 3: // iterate over some database query 4: // to add time to the execution of this method; 5: // the TableB has around 10 records 6: for (int i = 0; i < 10; i++) 7: { 8: DataClasses1DataContext dataContext = new DataClasses1DataContext(); 9: var query = from b in dataContext.TableBs select b; 10: 11: foreach (var row in query) 12: { 13: // Do NOTHING (wish my job was like this) 14: } 15: } 16:  17: return number % divisor == 0; 18: } Now, let’s look at how to modify this to PLINQ. 1: private static void Plinq(int lowerLimit, int upperLimit) 2: { 3: // populate an array with int values from lowerLimit to the upperLimit 4: var source = Enumerable.Range(lowerLimit, upperLimit); 5:  6: // Start a timer 7: Stopwatch stopwatch = new Stopwatch(); 8: stopwatch.Start(); 9:  10: // set the expectation => build the expression tree 11: var evenNumbers = from num in source.AsParallel() 12: where IsDivisibleBy(num, 2) 13: select num; 14:  15: // iterate over and print the returned items 16: foreach (var number in evenNumbers) 17: { 18: Console.WriteLine(string.Format("** {0}", number)); 19: } 20:  21: stopwatch.Stop(); 22:  23: // check the metrics 24: Console.WriteLine(String.Format("Elapsed {0}ms", stopwatch.ElapsedMilliseconds)); 25: } That’s it, this is now in PLINQ format. Oh and if you haven’t found the difference, look line 11 a little more closely. You’ll see an extension method ‘AsParallel()’ added to the ‘source’ variable. Couldn’t be more simpler right? So this is going to improve the performance for us. Let’s test it. So in my Main method of the Console application that I’m working on, I make a call to both. 1: static void Main(string[] args) 2: { 3: // set lower and upper limits 4: int lowerLimit = 1; 5: int upperLimit = 20; 6: // call the methods 7: Console.WriteLine("Calling Linq() method"); 8: Linq(lowerLimit, upperLimit); 9: 10: Console.WriteLine(); 11: Console.WriteLine("Calling Plinq() method"); 12: Plinq(lowerLimit, upperLimit); 13:  14: Console.ReadLine(); // just so I get enough time to read the output 15: } YMMV, but here are the results that I got:    It’s quite obvious from the above results that the Plinq() method is taking considerably less time than the Linq() version. I’m sure you’ve already noticed that the output of the Plinq() method is not in order. That’s because, each of the ‘control’s we sent to fetch the results, reported with values as and when they obtained them. This is something about parallel LINQ that one needs to remember – the collection cannot be guaranteed to be undisturbed. This could be counted as a negative about PLINQ (emphasize ‘could’). Nevertheless, if we want the collection to be sorted, we can use a SortedSet (.net 4.0) or build our own custom ‘sorter’. Either way we go, there’s a good chance we’ll end up with a better performance using PLINQ. And there’s another negative of PLINQ (depending on how you see it). This is regarding the CPU cycles. See the usage for Linq() method (used ResourceMonitor): I have dual CPU’s and see the height of the peak in the bottom two blocks and now compare to what happens when I run the Plinq() method. The difference is obvious. Higher usage, but for a shorter duration (width of the peak). Both these points make sense in both cases. Linq() runs for a longer time, but uses less resources whereas Plinq() runs for a shorter time and consumes more resources. Even after knowing all these, I’m still inclined towards PLINQ. PLINQ rocks! (no hard feelings LINQ)

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• Slow boot on Ubuntu 12.04

  - by Hailwood

  My Ubuntu is booting really slow (Windows is booting faster...). I am using Ubuntu a Dell Inspiron 1545 Pentium(R) Dual-Core CPU T4300 @ 2.10GHz, 4GB Ram, 500GB HDD running Ubuntu 12.04 with gnome-shell 3.4.1. After running dmesg the culprit seems to be this section, in particular the last three lines: [26.557659] ADDRCONF(NETDEV_UP): eth0: link is not ready [26.565414] ADDRCONF(NETDEV_UP): eth0: link is not ready [27.355355] Console: switching to colour frame buffer device 170x48 [27.362346] fb0: radeondrmfb frame buffer device [27.362347] drm: registered panic notifier [27.362357] [drm] Initialized radeon 2.12.0 20080528 for 0000:01:00.0 on minor 0 [27.617435] init: udev-fallback-graphics main process (1049) terminated with status 1 [30.064481] init: plymouth-stop pre-start process (1500) terminated with status 1 [51.708241] CE: hpet increased min_delta_ns to 20113 nsec [59.448029] eth2: no IPv6 routers present But I have no idea how to start debugging this. sudo lshw -C video $ sudo lshw -C video *-display description: VGA compatible controller product: RV710 [Mobility Radeon HD 4300 Series] vendor: Hynix Semiconductor (Hyundai Electronics) physical id: 0 bus info: pci@0000:01:00.0 version: 00 width: 32 bits clock: 33MHz capabilities: pm pciexpress msi vga_controller bus_master cap_list rom configuration: driver=fglrx_pci latency=0 resources: irq:48 memory:e0000000-efffffff ioport:de00(size=256) memory:f6df0000-f6dfffff memory:f6d00000-f6d1ffff After loading the propriety driver my new dmesg log is below (starting from the first major time gap): [2.983741] EXT4-fs (sda6): mounted filesystem with ordered data mode. Opts: (null) [25.094327] ADDRCONF(NETDEV_UP): eth0: link is not ready [25.119737] udevd[520]: starting version 175 [25.167086] lp: driver loaded but no devices found [25.215341] fglrx: module license 'Proprietary. (C) 2002 - ATI Technologies, Starnberg, GERMANY' taints kernel. [25.215345] Disabling lock debugging due to kernel taint [25.231924] wmi: Mapper loaded [25.318414] lib80211: common routines for IEEE802.11 drivers [25.318418] lib80211_crypt: registered algorithm 'NULL' [25.331631] [fglrx] Maximum main memory to use for locked dma buffers: 3789 MBytes. [25.332095] [fglrx] vendor: 1002 device: 9552 count: 1 [25.334206] [fglrx] ioport: bar 1, base 0xde00, size: 0x100 [25.334229] pci 0000:01:00.0: PCI INT A -> GSI 16 (level, low) -> IRQ 16 [25.334235] pci 0000:01:00.0: setting latency timer to 64 [25.337109] [fglrx] Kernel PAT support is enabled [25.337140] [fglrx] module loaded - fglrx 8.96.4 [Mar 12 2012] with 1 minors [25.342803] Adding 4189180k swap on /dev/sda7. Priority:-1 extents:1 across:4189180k [25.364031] type=1400 audit(1338241723.027:2): apparmor="STATUS" operation="profile_load" name="/sbin/dhclient" pid=606 comm="apparmor_parser" [25.364491] type=1400 audit(1338241723.031:3): apparmor="STATUS" operation="profile_load" name="/usr/lib/NetworkManager/nm-dhcp-client.action" pid=606 comm="apparmor_parser" [25.364760] type=1400 audit(1338241723.031:4): apparmor="STATUS" operation="profile_load" name="/usr/lib/connman/scripts/dhclient-script" pid=606 comm="apparmor_parser" [25.394328] wl 0000:0c:00.0: PCI INT A -> GSI 17 (level, low) -> IRQ 17 [25.394343] wl 0000:0c:00.0: setting latency timer to 64 [25.415531] acpi device:36: registered as cooling_device2 [25.416688] input: Video Bus as /devices/LNXSYSTM:00/device:00/PNP0A03:00/device:34/LNXVIDEO:00/input/input6 [25.416795] ACPI: Video Device [VID] (multi-head: yes rom: no post: no) [25.416865] [Firmware Bug]: Duplicate ACPI video bus devices for the same VGA controller, please try module parameter "video.allow_duplicates=1"if the current driver doesn't work. [25.425133] lib80211_crypt: registered algorithm 'TKIP' [25.448058] snd_hda_intel 0000:00:1b.0: PCI INT A -> GSI 21 (level, low) -> IRQ 21 [25.448321] snd_hda_intel 0000:00:1b.0: irq 47 for MSI/MSI-X [25.448353] snd_hda_intel 0000:00:1b.0: setting latency timer to 64 [25.738867] eth1: Broadcom BCM4315 802.11 Hybrid Wireless Controller 5.100.82.38 [25.761213] input: HDA Intel Mic as /devices/pci0000:00/0000:00:1b.0/sound/card0/input7 [25.761406] input: HDA Intel Headphone as /devices/pci0000:00/0000:00:1b.0/sound/card0/input8 [25.783432] dcdbas dcdbas: Dell Systems Management Base Driver (version 5.6.0-3.2) [25.908318] EXT4-fs (sda6): re-mounted. Opts: errors=remount-ro [25.928155] input: Dell WMI hotkeys as /devices/virtual/input/input9 [25.960561] udevd[543]: renamed network interface eth1 to eth2 [26.285688] init: failsafe main process (835) killed by TERM signal [26.396426] input: PS/2 Mouse as /devices/platform/i8042/serio2/input/input10 [26.423108] input: AlpsPS/2 ALPS GlidePoint as /devices/platform/i8042/serio2/input/input11 [26.511297] Bluetooth: Core ver 2.16 [26.511383] NET: Registered protocol family 31 [26.511385] Bluetooth: HCI device and connection manager initialized [26.511388] Bluetooth: HCI socket layer initialized [26.511391] Bluetooth: L2CAP socket layer initialized [26.512079] Bluetooth: SCO socket layer initialized [26.530164] Bluetooth: BNEP (Ethernet Emulation) ver 1.3 [26.530168] Bluetooth: BNEP filters: protocol multicast [26.553893] type=1400 audit(1338241724.219:5): apparmor="STATUS" operation="profile_replace" name="/sbin/dhclient" pid=928 comm="apparmor_parser" [26.554860] Bluetooth: RFCOMM TTY layer initialized [26.554866] Bluetooth: RFCOMM socket layer initialized [26.554868] Bluetooth: RFCOMM ver 1.11 [26.557910] type=1400 audit(1338241724.223:6): apparmor="STATUS" operation="profile_load" name="/usr/lib/lightdm/lightdm/lightdm-guest-session-wrapper" pid=927 comm="apparmor_parser" [26.559166] type=1400 audit(1338241724.223:7): apparmor="STATUS" operation="profile_replace" name="/usr/lib/NetworkManager/nm-dhcp-client.action" pid=928 comm="apparmor_parser" [26.559574] type=1400 audit(1338241724.223:8): apparmor="STATUS" operation="profile_replace" name="/usr/lib/connman/scripts/dhclient-script" pid=928 comm="apparmor_parser" [26.575519] type=1400 audit(1338241724.239:9): apparmor="STATUS" operation="profile_load" name="/usr/lib/telepathy/mission-control-5" pid=931 comm="apparmor_parser" [26.581100] type=1400 audit(1338241724.247:10): apparmor="STATUS" operation="profile_load" name="/usr/lib/telepathy/telepathy-*" pid=931 comm="apparmor_parser" [26.582794] type=1400 audit(1338241724.247:11): apparmor="STATUS" operation="profile_load" name="/usr/bin/evince" pid=929 comm="apparmor_parser" [26.605672] ppdev: user-space parallel port driver [27.592475] sky2 0000:09:00.0: eth0: enabling interface [27.604329] ADDRCONF(NETDEV_UP): eth0: link is not ready [27.606962] ADDRCONF(NETDEV_UP): eth0: link is not ready [27.852509] vesafb: mode is 1024x768x32, linelength=4096, pages=0 [27.852513] vesafb: scrolling: redraw [27.852515] vesafb: Truecolor: size=0:8:8:8, shift=0:16:8:0 [27.852523] mtrr: type mismatch for e0000000,400000 old: write-back new: write-combining [27.852527] mtrr: type mismatch for e0000000,200000 old: write-back new: write-combining [27.852531] mtrr: type mismatch for e0000000,100000 old: write-back new: write-combining [27.852534] mtrr: type mismatch for e0000000,80000 old: write-back new: write-combining [27.852538] mtrr: type mismatch for e0000000,40000 old: write-back new: write-combining [27.852541] mtrr: type mismatch for e0000000,20000 old: write-back new: write-combining [27.852544] mtrr: type mismatch for e0000000,10000 old: write-back new: write-combining [27.852548] mtrr: type mismatch for e0000000,8000 old: write-back new: write-combining [27.852551] mtrr: type mismatch for e0000000,4000 old: write-back new: write-combining [27.852554] mtrr: type mismatch for e0000000,2000 old: write-back new: write-combining [27.852558] mtrr: type mismatch for e0000000,1000 old: write-back new: write-combining [27.853154] vesafb: framebuffer at 0xe0000000, mapped to 0xffffc90005580000, using 3072k, total 3072k [27.853405] Console: switching to colour frame buffer device 128x48 [27.853426] fb0: VESA VGA frame buffer device [28.539800] fglrx_pci 0000:01:00.0: irq 48 for MSI/MSI-X [28.540552] [fglrx] Firegl kernel thread PID: 1168 [28.540679] [fglrx] Firegl kernel thread PID: 1169 [28.540789] [fglrx] Firegl kernel thread PID: 1170 [28.540932] [fglrx] IRQ 48 Enabled [29.845620] [fglrx] Gart USWC size:1236 M. [29.845624] [fglrx] Gart cacheable size:489 M. [29.845629] [fglrx] Reserved FB block: Shared offset:0, size:1000000 [29.845632] [fglrx] Reserved FB block: Unshared offset:fc21000, size:3df000 [29.845635] [fglrx] Reserved FB block: Unshared offset:1fffb000, size:5000 [59.700023] eth2: no IPv6 routers present

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• ASP.NET MVC–How to show asterisk after required field label

  - by DigiMortal

  Usually we have some required fields on our forms and it would be nice if ASP.NET MVC views can detect those fields automatically and display nice red asterisk after field label. As this functionality is not built in I built my own solution based on data annotations. In this posting I will show you how to show red asterisk after label of required fields. Here are the main information sources I used when working out my own solution: How can I modify LabelFor to display an asterisk on required fields? (stackoverflow) ASP.NET MVC – Display visual hints for the required fields in your model (Radu Enuca) Although my code was first written for completely different situation I needed it later and I modified it to work with models that use data annotations. If data member of model has Required attribute set then asterisk is rendered after field. If Required attribute is missing then there will be no asterisk. Here’s my code. You can take just LabelForRequired() methods and paste them to your own HTML extension class. public static class HtmlExtensions {     [SuppressMessage("Microsoft.Design", "CA1006:DoNotNestGenericTypesInMemberSignatures", Justification = "This is an appropriate nesting of generic types")]     public static MvcHtmlString LabelForRequired<TModel, TValue>(this HtmlHelper<TModel> html, Expression<Func<TModel, TValue>> expression, string labelText = "")     {         return LabelHelper(html,             ModelMetadata.FromLambdaExpression(expression, html.ViewData),             ExpressionHelper.GetExpressionText(expression), labelText);     }       private static MvcHtmlString LabelHelper(HtmlHelper html,         ModelMetadata metadata, string htmlFieldName, string labelText)     {         if (string.IsNullOrEmpty(labelText))         {             labelText = metadata.DisplayName ?? metadata.PropertyName ?? htmlFieldName.Split('.').Last();         }           if (string.IsNullOrEmpty(labelText))         {             return MvcHtmlString.Empty;         }           bool isRequired = false;           if (metadata.ContainerType != null)         {             isRequired = metadata.ContainerType.GetProperty(metadata.PropertyName)                             .GetCustomAttributes(typeof(RequiredAttribute), false)                             .Length == 1;         }           TagBuilder tag = new TagBuilder("label");         tag.Attributes.Add(             "for",             TagBuilder.CreateSanitizedId(                 html.ViewContext.ViewData.TemplateInfo.GetFullHtmlFieldName(htmlFieldName)             )         );           if (isRequired)             tag.Attributes.Add("class", "label-required");           tag.SetInnerText(labelText);           var output = tag.ToString(TagRenderMode.Normal);             if (isRequired)         {             var asteriskTag = new TagBuilder("span");             asteriskTag.Attributes.Add("class", "required");             asteriskTag.SetInnerText("*");             output += asteriskTag.ToString(TagRenderMode.Normal);         }         return MvcHtmlString.Create(output);     } } And here’s how to use LabelForRequired extension method in your view: <div class="field">     @Html.LabelForRequired(m => m.Name)     @Html.TextBoxFor(m => m.Name)     @Html.ValidationMessageFor(m => m.Name) </div> After playing with CSS style called .required my example form looks like this: These red asterisks are not part of original view mark-up. LabelForRequired method detected that these properties have Required attribute set and rendered out asterisks after field names. NB! By default asterisks are not red. You have to define CSS class called “required” to modify how asterisk looks like and how it is positioned.

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• My Code Kata–A Solution Kata

  - by Glav

  There are many developers and coders out there who like to do code Kata’s to keep their coding ability up to scratch and to practice their skills. I think it is a good idea. While I like the concept, I find them dead boring and of minimal purpose. Yes, they serve to hone your skills but that’s about it. They are often quite abstract, in that they usually focus on a small problem set requiring specific solutions. It is fair enough as that is how they are designed but again, I find them quite boring. What I personally like to do is go for something a little larger and a little more fun. It takes a little more time and is not as easily executed as a kata though, but it services the same purposes from a practice perspective and allows me to continue to solve some problems that are not directly part of the initial goal. This means I can cover a broader learning range and have a bit more fun. If I am lucky, sometimes they even end up being useful tools. With that in mind, I thought I’d share my current ‘kata’. It is not really a code kata as it is too big. I prefer to think of it as a ‘solution kata’. The code is on bitbucket here. What I wanted to do was create a kind of simplistic virtual world where I can create a player, or a class, stuff it into the world, and see if it survives, and can navigate its way to the exit. Requirements were pretty simple: Must be able to define a map to describe the world using simple X,Y co-ordinates. Z co-ordinates as well if you feel like getting clever. Should have the concept of entrances, exists, solid blocks, and potentially other materials (again if you want to get clever). A coder should be able to easily write a class which will act as an inhabitant of the world. An inhabitant will receive stimulus from the world in the form of surrounding environment and be able to make a decision on action which it passes back to the ‘world’ for processing. At a minimum, an inhabitant will have sight and speed characteristics which determine how far they can ‘see’ in the world, and how fast they can move. Coders who write a really bad ‘inhabitant’ should not adversely affect the rest of world. Should allow multiple inhabitants in the world. So that was the solution I set out to act as a practice solution and a little bit of fun. It had some interesting problems to solve and I figured, if it turned out ok, I could potentially use this as a ‘developer test’ for interviews. Ask a potential coder to write a class for an inhabitant. Show the coder the map they will navigate, but also mention that we will use their code to navigate a map they have not yet seen and a little more complex. I have been playing with solution for a short time now and have it working in basic concepts. Below is a screen shot using a very basic console visualiser that shows the map, boundaries, blocks, entrance, exit and players/inhabitants. The yellow asterisks ‘*’ are the players, green ‘O’ the entrance, purple ‘^’ the exit, maroon/browny ‘#’ are solid blocks. The players can move around at different speeds, knock into each others, and make directional movement decisions based on what they see and who is around them. It has been quite fun to write and it is also quite fun to develop different players to inject into the world. The code below shows a really simple implementation of an inhabitant that can work out what to do based on stimulus from the world. It is pretty simple and just tries to move in some direction if there is nothing blocking the path. public class TestPlayer:LivingEntity { public TestPlayer() { Name = "Beta Boy"; LifeKey = Guid.NewGuid(); } public override ActionResult DecideActionToPerform(EcoDev.Core.Common.Actions.ActionContext actionContext) { try { var action = new MovementAction(); // move forward if we can if (actionContext.Position.ForwardFacingPositions.Length > 0) { if (CheckAccessibilityOfMapBlock(actionContext.Position.ForwardFacingPositions[0])) { action.DirectionToMove = MovementDirection.Forward; return action; } } if (actionContext.Position.LeftFacingPositions.Length > 0) { if (CheckAccessibilityOfMapBlock(actionContext.Position.LeftFacingPositions[0])) { action.DirectionToMove = MovementDirection.Left; return action; } } if (actionContext.Position.RearFacingPositions.Length > 0) { if (CheckAccessibilityOfMapBlock(actionContext.Position.RearFacingPositions[0])) { action.DirectionToMove = MovementDirection.Back; return action; } } if (actionContext.Position.RightFacingPositions.Length > 0) { if (CheckAccessibilityOfMapBlock(actionContext.Position.RightFacingPositions[0])) { action.DirectionToMove = MovementDirection.Right; return action; } } return action; } catch (Exception ex) { World.WriteDebugInformation("Player: "+ Name, string.Format("Player Generated exception: {0}",ex.Message)); throw ex; } } private bool CheckAccessibilityOfMapBlock(MapBlock block) { if (block == null || block.Accessibility == MapBlockAccessibility.AllowEntry || block.Accessibility == MapBlockAccessibility.AllowExit || block.Accessibility == MapBlockAccessibility.AllowPotentialEntry) { return true; } return false; } } It is simple and it seems to work well. The world implementation itself decides the stimulus context that is passed to he inhabitant to make an action decision. All movement is carried out on separate threads and timed appropriately to be as fair as possible and to cater for additional skills such as speed, and eventually maybe stamina, strength, with actions like fighting. It is pretty fun to make up random maps and see how your inhabitant does. You can download the code from here. Along the way I have played with parallel extensions to make the compute intensive stuff spread across all cores, had to heavily factor in visibility of methods and properties so design of classes was paramount, work out movement algorithms that play fairly in the world and properly favour the players with higher abilities, as well as a host of other issues. So that is my ‘solution kata’. If I keep going with it, I may develop a web interface for it where people can upload assemblies and watch their player within a web browser visualiser and maybe even a map designer. What do you do to keep the fires burning?

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• The Shift: how Orchard painlessly shifted to document storage, and how it’ll affect you

  - by Bertrand Le Roy

  We’ve known it all along. The storage for Orchard content items would be much more efficient using a document database than a relational one. Orchard content items are composed of parts that serialize naturally into infoset kinds of documents. Storing them as relational data like we’ve done so far was unnatural and requires the data for a single item to span multiple tables, related through 1-1 relationships. This means lots of joins in queries, and a great potential for Select N+1 problems. Document databases, unfortunately, are still a tough sell in many places that prefer the more familiar relational model. Being able to x-copy Orchard to hosters has also been a basic constraint in the design of Orchard. Combine those with the necessity at the time to run in medium trust, and with license compatibility issues, and you’ll find yourself with very few reasonable choices. So we went, a little reluctantly, for relational SQL stores, with the dream of one day transitioning to document storage. We have played for a while with the idea of building our own document storage on top of SQL databases, and Sébastien implemented something more than decent along those lines, but we had a better way all along that we didn’t notice until recently… In Orchard, there are fields, which are named properties that you can add dynamically to a content part. Because they are so dynamic, we have been storing them as XML into a column on the main content item table. This infoset storage and its associated API are fairly generic, but were only used for fields. The breakthrough was when Sébastien realized how this existing storage could give us the advantages of document storage with minimal changes, while continuing to use relational databases as the substrate. public bool CommercialPrices { get { return this.Retrieve(p => p.CommercialPrices); } set { this.Store(p => p.CommercialPrices, value); } } This code is very compact and efficient because the API can infer from the expression what the type and name of the property are. It is then able to do the proper conversions for you. For this code to work in a content part, there is no need for a record at all. This is particularly nice for site settings: one query on one table and you get everything you need. This shows how the existing infoset solves the data storage problem, but you still need to query. Well, for those properties that need to be filtered and sorted on, you can still use the current record-based relational system. This of course continues to work. We do however provide APIs that make it trivial to store into both record properties and the infoset storage in one operation: public double Price { get { return Retrieve(r => r.Price); } set { Store(r => r.Price, value); } } This code looks strikingly similar to the non-record case above. The difference is that it will manage both the infoset and the record-based storages. The call to the Store method will send the data in both places, keeping them in sync. The call to the Retrieve method does something even cooler: if the property you’re looking for exists in the infoset, it will return it, but if it doesn’t, it will automatically look into the record for it. And if that wasn’t cool enough, it will take that value from the record and store it into the infoset for the next time it’s required. This means that your data will start automagically migrating to infoset storage just by virtue of using the code above instead of the usual: public double Price { get { return Record.Price; } set { Record.Price = value; } } As your users browse the site, it will get faster and faster as Select N+1 issues will optimize themselves away. If you preferred, you could still have explicit migration code, but it really shouldn’t be necessary most of the time. If you do already have code using QueryHints to mitigate Select N+1 issues, you might want to reconsider those, as with the new system, you’ll want to avoid joins that you don’t need for filtering or sorting, further optimizing your queries. There are some rare cases where the storage of the property must be handled differently. Check out this string[] property on SearchSettingsPart for example: public string[] SearchedFields { get { return (Retrieve<string>("SearchedFields") ?? "") .Split(new[] {',', ' '}, StringSplitOptions.RemoveEmptyEntries); } set { Store("SearchedFields", String.Join(", ", value)); } } The array of strings is transformed by the property accessors into and from a comma-separated list stored in a string. The Retrieve and Store overloads used in this case are lower-level versions that explicitly specify the type and name of the attribute to retrieve or store. You may be wondering what this means for code or operations that look directly at the database tables instead of going through the new infoset APIs. Even if there is a record, the infoset version of the property will win if it exists, so it is necessary to keep the infoset up-to-date. It’s not very complicated, but definitely something to keep in mind. Here is what a product record looks like in Nwazet.Commerce for example: And here is the same data in the infoset: The infoset is stored in Orchard_Framework_ContentItemRecord or Orchard_Framework_ContentItemVersionRecord, depending on whether the content type is versionable or not. A good way to find what you’re looking for is to inspect the record table first, as it’s usually easier to read, and then get the item record of the same id. Here is the detailed XML document for this product: <Data> <ProductPart Inventory="40" Price="18" Sku="pi-camera-box" OutOfStockMessage="" AllowBackOrder="false" Weight="0.2" Size="" ShippingCost="null" IsDigital="false" /> <ProductAttributesPart Attributes="" /> <AutoroutePart DisplayAlias="camera-box" /> <TitlePart Title="Nwazet Pi Camera Box" /> <BodyPart Text="[...]" /> <CommonPart CreatedUtc="2013-09-10T00:39:00Z" PublishedUtc="2013-09-14T01:07:47Z" /> </Data> The data is neatly organized under each part. It is easy to see how that document is all you need to know about that content item, all in one table. If you want to modify that data directly in the database, you should be careful to do it in both the record table and the infoset in the content item record. In this configuration, the record is now nothing more than an index, and will only be used for sorting and filtering. Of course, it’s perfectly fine to mix record-backed properties and record-less properties on the same part. It really depends what you think must be sorted and filtered on. In turn, this potentially simplifies migrations considerably. So here it is, the great shift of Orchard to document storage, something that Orchard has been designed for all along, and that we were able to implement with a satisfying and surprising economy of resources. Expect this code to make its way into the 1.8 version of Orchard when that’s available.

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• C# Extension Methods - To Extend or Not To Extend...

  - by James Michael Hare

  I've been thinking a lot about extension methods lately, and I must admit I both love them and hate them. They are a lot like sugar, they taste so nice and sweet, but they'll rot your teeth if you eat them too much.   I can't deny that they aren't useful and very handy. One of the major components of the Shared Component library where I work is a set of useful extension methods. But, I also can't deny that they tend to be overused and abused to willy-nilly extend every living type.   So what constitutes a good extension method? Obviously, you can write an extension method for nearly anything whether it is a good idea or not. Many times, in fact, an idea seems like a good extension method but in retrospect really doesn't fit.   So what's the litmus test? To me, an extension method should be like in the movies when a person runs into their twin, separated at birth. You just know you're related. Obviously, that's hard to quantify, so let's try to put a few rules-of-thumb around them.   A good extension method should:     Apply to any possible instance of the type it extends.     Simplify logic and improve readability/maintainability.     Apply to the most specific type or interface applicable.     Be isolated in a namespace so that it does not pollute IntelliSense.     So let's look at a few examples in relation to these rules.   The first rule, to me, is the most important of all. Once again, it bears repeating, a good extension method should apply to all possible instances of the type it extends. It should feel like the long lost relative that should have been included in the original class but somehow was missing from the family tree.    Take this nifty little int extension, I saw this once in a blog and at first I really thought it was pretty cool, but then I started noticing a code smell I couldn't quite put my finger on. So let's look:       public static class IntExtensinos     {         public static int Seconds(int num)         {             return num * 1000;         }           public static int Minutes(int num)         {             return num * 60000;         }     }     This is so you could do things like:       ...     Thread.Sleep(5.Seconds());     ...     proxy.Timeout = 1.Minutes();     ...     Awww, you say, that's cute! Well, that's the problem, it's kitschy and it doesn't always apply (and incidentally you could achieve the same thing with TimeStamp.FromSeconds(5)). It's syntactical candy that looks cool, but tends to rot and pollute the code. It would allow things like:       total += numberOfTodaysOrders.Seconds();     which makes no sense and should never be allowed. The problem is you're applying an extension method to a logical domain, not a type domain. That is, the extension method Seconds() doesn't really apply to ALL ints, it applies to ints that are representative of time that you want to convert to milliseconds.    Do you see what I mean? The two problems, in a nutshell, are that a) Seconds() called off a non-time value makes no sense and b) calling Seconds() off something to pass to something that does not take milliseconds will be off by a factor of 1000 or worse.   Thus, in my mind, you should only ever have an extension method that applies to the whole domain of that type.   For example, this is one of my personal favorites:       public static bool IsBetween<T>(this T value, T low, T high)         where T : IComparable<T>     {         return value.CompareTo(low) >= 0 && value.CompareTo(high) <= 0;     }   This allows you to check if any IComparable<T> is within an upper and lower bound. Think of how many times you type something like:       if (response.Employee.Address.YearsAt >= 2         && response.Employee.Address.YearsAt <= 10)     {     ...     }     Now, you can instead type:       if(response.Employee.Address.YearsAt.IsBetween(2, 10))     {     ...     }     Note that this applies to all IComparable<T> -- that's ints, chars, strings, DateTime, etc -- and does not depend on any logical domain. In addition, it satisfies the second point and actually makes the code more readable and maintainable.   Let's look at the third point. In it we said that an extension method should fit the most specific interface or type possible. Now, I'm not saying if you have something that applies to enumerables, you create an extension for List, Array, Dictionary, etc (though you may have reasons for doing so), but that you should beware of making things TOO general.   For example, let's say we had an extension method like this:       public static T ConvertTo<T>(this object value)     {         return (T)Convert.ChangeType(value, typeof(T));     }         This lets you do more fluent conversions like:       double d = "5.0".ConvertTo<double>();     However, if you dig into Reflector (LOVE that tool) you will see that if the type you are calling on does not implement IConvertible, what you convert to MUST be the exact type or it will throw an InvalidCastException. Now this may or may not be what you want in this situation, and I leave that up to you. Things like this would fail:       object value = new Employee();     ...     // class cast exception because typeof(IEmployee) != typeof(Employee)     IEmployee emp = value.ConvertTo<IEmployee>();       Yes, that's a downfall of working with Convertible in general, but if you wanted your fluent interface to be more type-safe so that ConvertTo were only callable on IConvertibles (and let casting be a manual task), you could easily make it:         public static T ConvertTo<T>(this IConvertible value)     {         return (T)Convert.ChangeType(value, typeof(T));     }         This is what I mean by choosing the best type to extend. Consider that if we used the previous (object) version, every time we typed a dot ('.') on an instance we'd pull up ConvertTo() whether it was applicable or not. By filtering our extension method down to only valid types (those that implement IConvertible) we greatly reduce our IntelliSense pollution and apply a good level of compile-time correctness.   Now my fourth rule is just my general rule-of-thumb. Obviously, you can make extension methods as in-your-face as you want. I included all mine in my work libraries in its own sub-namespace, something akin to:       namespace Shared.Core.Extensions { ... }     This is in a library called Shared.Core, so just referencing the Core library doesn't pollute your IntelliSense, you have to actually do a using on Shared.Core.Extensions to bring the methods in. This is very similar to the way Microsoft puts its extension methods in System.Linq. This way, if you want 'em, you use the appropriate namespace. If you don't want 'em, they won't pollute your namespace.   To really make this work, however, that namespace should only include extension methods and subordinate types those extensions themselves may use. If you plant other useful classes in those namespaces, once a user includes it, they get all the extensions too.   Also, just as a personal preference, extension methods that aren't simply syntactical shortcuts, I like to put in a static utility class and then have extension methods for syntactical candy. For instance, I think it imaginable that any object could be converted to XML:       namespace Shared.Core     {         // A collection of XML Utility classes         public static class XmlUtility         {             ...             // Serialize an object into an xml string             public static string ToXml(object input)             {                 var xs = new XmlSerializer(input.GetType());                   // use new UTF8Encoding here, not Encoding.UTF8. The later includes                 // the BOM which screws up subsequent reads, the former does not.                 using (var memoryStream = new MemoryStream())                 using (var xmlTextWriter = new XmlTextWriter(memoryStream, new UTF8Encoding()))                 {                     xs.Serialize(xmlTextWriter, input);                     return Encoding.UTF8.GetString(memoryStream.ToArray());                 }             }             ...         }     }   I also wanted to be able to call this from an object like:       value.ToXml();     But here's the problem, if i made this an extension method from the start with that one little keyword "this", it would pop into IntelliSense for all objects which could be very polluting. Instead, I put the logic into a utility class so that users have the choice of whether or not they want to use it as just a class and not pollute IntelliSense, then in my extensions namespace, I add the syntactical candy:       namespace Shared.Core.Extensions     {         public static class XmlExtensions         {             public static string ToXml(this object value)             {                 return XmlUtility.ToXml(value);             }         }     }   So now it's the best of both worlds. On one hand, they can use the utility class if they don't want to pollute IntelliSense, and on the other hand they can include the Extensions namespace and use as an extension if they want. The neat thing is it also adheres to the Single Responsibility Principle. The XmlUtility is responsible for converting objects to XML, and the XmlExtensions is responsible for extending object's interface for ToXml().

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• Applications: How to create a custom dialog box for Windows Mobile 6 (native)

  - by TechTwaddle

  Ashraf, on the MSDN forum, asks, “Is there a way to make a default choice for the messagebox that happens after a period of time if the user doesn't choose (Clicked ) Yes or No buttons.” To elaborate, the requirement is to show a message box to the user with certain options to select, and if the user does not respond within a predefined time limit (say 8 seconds) then the message box must dismiss itself and select a default option. Now such a functionality is not available with the MessageBox() api, you will have to write your own custom dialog box. Surely, creating a dialog box is quite a simple task using the DialogBox() api, and we have been creating full screen dialog boxes all the while. So how will this custom message box be any different? It’s not much different from a regular dialog box except for a few changes in its properties. First, it has a title bar but no buttons on the title bar (no ‘x’ or ‘ok’ button on the title bar), it doesn’t occupy full screen and it contains the controls that you put into it, thus justifying the title ‘custom’. So in this post we create a custom dialog box with two buttons, ‘Black’ and ‘White’. The user is given 8 seconds to select one of those colours, if the user doesn’t make a selection in 8 seconds, the default option ‘Black’ is selected. Before going into the implementation here is a video of how the dialog box works; Custom dialog box To start off, add a new dialog resource into your application, size it appropriately and add whatever controls you need to the dialog. In my case, I added two static text labels and two buttons, as below; Now we need to write up the window procedure for this dialog, here is the complete function; BOOL CALLBACK CustomDialogProc(HWND hDlg, UINT uMessage, WPARAM wParam, LPARAM lParam) {     int wmID, wmEvent;     PAINTSTRUCT ps;     HDC hdc;     static int timeCount = 0;     switch(uMessage)     {         case WM_INITDIALOG:             {                 SHINITDLGINFO shidi;                 memset(&shidi, 0, sizeof(shidi));                 shidi.dwMask = SHIDIM_FLAGS;                 //shidi.dwFlags = SHIDIF_DONEBUTTON | SHIDIF_SIPDOWN | SHIDIF_SIZEDLGFULLSCREEN | SHIDIF_EMPTYMENU;                 shidi.dwFlags = SHIDIF_SIPDOWN | SHIDIF_EMPTYMENU;                 shidi.hDlg = hDlg;                 SHInitDialog(&shidi);                 SHDoneButton(hDlg, SHDB_HIDE);                 timeCount = 0;                 SetWindowText(GetDlgItem(hDlg, IDC_STATIC_TIME_REMAINING), L"Time remaining: 8 second(s)");                 SetTimer(hDlg, MY_TIMER, 1000, NULL);             }             return TRUE;         case WM_COMMAND:             {                 wmID = LOWORD(wParam);                 wmEvent = HIWORD(wParam);                 switch(wmID)                 {                     case IDC_BUTTON_BLACK:                         KillTimer(hDlg, MY_TIMER);                         EndDialog(hDlg, IDC_BUTTON_BLACK);                         break;                     case IDC_BUTTON_WHITE:                         KillTimer(hDlg, MY_TIMER);                         EndDialog(hDlg, IDC_BUTTON_WHITE);                         break;                 }             }             break;         case WM_TIMER:             {                 if (wParam == MY_TIMER)                 {                     WCHAR wszText[128];                     memset(&wszText, 0, sizeof(wszText));                     timeCount++;                     //8 seconds are over, dismiss the dialog, select def value                     if (timeCount >= 8)                     {                         KillTimer(hDlg, MY_TIMER);                         EndDialog(hDlg, IDC_BUTTON_BLACK_DEF);                     }                     wsprintf(wszText, L"Time remaining: %d second(s)", 8-timeCount);                     SetWindowText(GetDlgItem(hDlg, IDC_STATIC_TIME_REMAINING), wszText);                     UpdateWindow(GetDlgItem(hDlg, IDC_STATIC_TIME_REMAINING));                 }             }             break;         case WM_PAINT:             {                 hdc = BeginPaint(hDlg, &ps);                 EndPaint(hDlg, &ps);             }             break;     }     return FALSE; } The MSDN documentation mentions that you need to specify the flag WS_NONAVDONEBUTTON, but I got an error saying that the value could not be found, so we can ignore this for now. Next up, while calling SHInitDialog() for your custom dialog, make sure that you don’t specify SHDIF_DONEBUTTON in the dwFlags member of the SHINITDIALOG structure, this member makes the ‘ok’ button appear on the dialog title bar. Finally, we need to call SHDoneButton() with SHDB_HIDE flag to, well, hide the Done button. The ‘Done’ button is the same as the ‘ok’ button, so this step might seem redundant, and the dialog works fine without calling SHDoneButton() too, but it’s better to stick with the documentation (; So you can see that we have followed all these steps above, under WM_INITDIALOG. We also setup a few things like a variable to keep track of the time, and setting off a one second timer. Every time the timer fires, we receive a WM_TIMER message. We then update the static label displaying the amount of time left to the user. If 8 seconds go by without the user selecting any option, we kill the timer and end the dialog with IDC_BUTTON_BLACK_DEF. This is just a #define’d integer value, make sure it’s unique. You’ll see why this is important. If the user makes a selection, either Black or White, we kill the timer and end the dialog with corresponding selection the user made, that is, either IDC_BUTTON_BLACK or IDC_BUTTON_WHITE. Ok, so now our custom dialog is ready to be used. I invoke the custom dialog from a menu entry in the main windows as below, case IDM_MENU_CUSTOMDLG:     {         int ret = DialogBox(g_hInst, MAKEINTRESOURCE(IDD_CUSTOM_DIALOG), hWnd, CustomDialogProc);         switch(ret)         {             case IDC_BUTTON_BLACK_DEF:                 SetWindowText(g_hStaticSelection, L"You Selected: Black (default)");                 break;             case IDC_BUTTON_BLACK:                 SetWindowText(g_hStaticSelection, L"You Selected: Black");                 break;             case IDC_BUTTON_WHITE:                 SetWindowText(g_hStaticSelection, L"You Selected: White");                 break;         }         UpdateWindow(g_hStaticSelection);     }     break; So you see why ending the dialog with the corresponding value was important, that’s what the DialogBox() api returns with. And in the main window I update a static text label to show which option was selected. I cranked this out in about an hour, and unfortunately don’t have time for a managed C# version. That will have to be another post, if I manage to get it working that is (;

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• Memory Efficient Windows SOA Server

  - by Antony Reynolds

  Installing a Memory Efficient SOA Suite 11.1.1.6 on Windows Server Well 11.1.1.6 is now available for download so I thought I would build a Windows Server environment to run it.  I will minimize the memory footprint of the installation by putting all functionality into the Admin Server of the SOA Suite domain. Required Software 64-bit JDK SOA Suite If you want 64-bit then choose “Generic” rather than “Microsoft Windows 32bit JVM” or “Linux 32bit JVM” This has links to all the required software. If you choose “Generic” then the Repository Creation Utility link does not show, you still need this so change the platform to “Microsoft Windows 32bit JVM” or “Linux 32bit JVM” to get the software. Similarly if you need a database then you need to change the platform to get the link to XE for Windows or Linux. If possible I recommend installing a 64-bit JDK as this allows you to assign more memory to individual JVMs. Windows XE will work, but it is better if you can use a full Oracle database because of the limitations on XE that sometimes cause it to run out of space with large or multiple SOA deployments. Installation Steps The following flow chart outlines the steps required in installing and configuring SOA Suite. The steps in the diagram are explained below. 64-bit? Is a 64-bit installation required?  The Windows & Linux installers will install 32-bit versions of the Sun JDK and JRockit.  A separate JDK must be installed for 64-bit. Install 64-bit JDK The 64-bit JDK can be either Hotspot or JRockit.  You can choose either JDK 1.7 or 1.6. Install WebLogic If you are using 64-bit then install WebLogic using “java –jar wls1036_generic.jar”.  Make sure you include Coherence in the installation, the easiest way to do this is to accept the “Typical” installation. SOA Suite Required? If you are not installing SOA Suite then you can jump straight ahead and create a WebLogic domain. Install SOA Suite Run the SOA Suite installer and point it at the existing Middleware Home created for WebLogic.  Note to run the SOA installer on Windows the user must have admin privileges.  I also found that on Windows Server 2008R2 I had to start the installer from a command prompt with administrative privileges, granting it privileges when it ran caused it to ignore the jreLoc parameter. Database Available? Do you have access to a database into which you can install the SOA schema.  SOA Suite requires access to an Oracle database (it is supported on other databases but I would always use an oracle database). Install Database I use an 11gR2 Oracle database to avoid XE limitations.  Make sure that you set the database character set to be unicode (AL32UTF8).  I also disabled the new security settings because they get in the way for a developer database.  Don’t forget to check that number of processes is at least 150 and number of sessions is not set, or is set to at least 200 (in the DB init parameters). Run RCU The SOA Suite database schemas are created by running the Repository Creation Utility.  Install the “SOA and BPM Infrastructure” component to support SOA Suite.  If you keep the schema prefix as “DEV” then the config wizard is easier to complete. Run Config Wizard The Config wizard creates the domain which hosts the WebLogic server instances.  To get a minimum footprint SOA installation choose the “Oracle Enterprise Manager” and “Oracle SOA Suite for developers” products.  All other required products will be automatically selected. The “for developers” installs target the appropriate components at the AdminServer rather than creating a separate managed server to house them.  This reduces the number of JVMs required to run the system and hence the amount of memory required.  This is not suitable for anything other than a developer environment as it mixes the admin and runtime functions together in a single server.  It also takes a long time to load all the required modules, making start up a slow process. If it exists I would recommend running the config wizard found in the “oracle_common/common/bin” directory under the middleware home.  This should have access to all the templates, including SOA. If you also want to run BAM in the same JVM as everything else then you need to “Select Optional Configuration” for “Managed Servers, Clusters and Machines”. To target BAM at the AdminServer delete the “bam_server1” managed server that is created by default.  This will result in BAM being targeted at the AdminServer. Installation Issues I had a few problems when I came to test everything in my mega-JVM. Following applications were not targeted and so I needed to target them at the AdminServer: b2bui composer Healthcare UI FMW Welcome Page Application (11.1.0.0.0) How Memory Efficient is It? On a Windows 2008R2 Server running under VirtualBox I was able to bring up both the 11gR2 database and SOA/BPM/BAM in 3G memory.  I allocated a minimum 512M to the PermGen and a minimum of 1.5G for the heap.  The setting from setSOADomainEnv are shown below: set DEFAULT_MEM_ARGS=-Xms1536m -Xmx2048m set PORT_MEM_ARGS=-Xms1536m -Xmx2048m set DEFAULT_MEM_ARGS=%DEFAULT_MEM_ARGS% -XX:PermSize=512m -XX:MaxPermSize=768m set PORT_MEM_ARGS=%PORT_MEM_ARGS% -XX:PermSize=512m -XX:MaxPermSize=768m I arrived at these numbers by monitoring JVM memory usage in JConsole. Task Manager showed total system memory usage at 2.9G – just below the 3G I allocated to the VM. Performance is not stellar but it runs and I could run JDeveloper alongside it on my 8G laptop, so in that sense it was a result!

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• How do I prove or disprove "god" objects are wrong?

  - by honestduane

  Problem Summary: Long story short, I inherited a code base and an development team I am not allowed to replace and the use of God Objects is a big issue. Going forward, I want to have us re-factor things but I am getting push-back from the teams who want to do everything with God Objects "because its easier" and this means I would not be allowed to re-factor. I pushed back citing my years of dev experience, that I'm the new boss who was hired to know these things, etc, and so did the third party offshore companies account sales rep, and this is now at the executive level and my meeting is tomorrow and I want to go in with a lot of technical ammo to advocate best practices because I feel it will be cheaper in the long run (And I personally feel that is what the third party is worried about) for the company. My issue is from a technical level, I know its good long term but I'm having trouble with the ultra short term and 6 months term, and while its something I "know" I cant prove it with references and cited resources outside of one person (Robert C. Martin, aka Uncle Bob), as that is what I am being asked to do as I have been told having data from one person and only one person (Robert C Martin) is not good enough of an argument. Question: What are some resources I can cite directly (Title, year published, page number, quote) by well known experts in the field that explicitly say this use of "God" Objects/Classes/Systems is bad (or good, since we are looking for the most technically valid solution)? Research I have already done: I have a number of books here and I have searched their indexes for the use of the words "god object" and "god class". I found that oddly its almost never used and the copy of the GoF book I have for example, never uses it (At least according to the index in front of me) but I have found it in 2 books per the below, but I want more I can use. I checked the Wikipedia page for "God Object" and its currently a stub with little reference links so although I personally agree with that it says, It doesn't have much I can use in an environment where personal experience is not considered valid. The book cited is also considered too old to be valid by the people I am debating these technical points with as the argument they are making is that "it was once thought to be bad but nobody could prove it, and now modern software says "god" objects are good to use". I personally believe that this statement is incorrect, but I want to prove the truth, whatever it is. In Robert C Martin's "Agile Principles, Patterns, and Practices in C#" (ISBN: 0-13-185725-8, hardcover) where on page 266 it states "Everybody knows that god classes are a bad idea. We don't want to concentrate all the intelligence of a system into a single object or a single function. One of the goals of OOD is the partitioning and distribution of behavior into many classes and many function." -- And then goes on to say sometimes its better to use God Classes anyway sometimes (Citing micro-controllers as an example). In Robert C Martin's "Clean Code: A Handbook of Agile Software Craftsmanship" page 136 (And only this page) talks about the "God class" and calls it out as a prime example of a violation of the "classes should be small" rule he uses to promote the Single Responsibility Principle" starting on on page 138. The problem I have is all my references and citations come from the same person (Robert C. Martin), and am from the same single person/source. I am being told that because he is just one guy, my desire to not use "God Classes" is invalid and not accepted as a standard best practice in the software industry. Is this true? Am I doing things wrong from a technical perspective by trying to keep to the teaching of Uncle Bob? God Objects and Object Oriented Programming and Design: The more I think of this the more I think this is more something you learn when you study OOP and its never explicitly called out; Its implicit to good design is my thinking (Feel free to correct me, please, as I want to learn), The problem is I "know" this, but but not everybody does, so in this case its not considered a valid argument because I am effectively calling it out as universal truth when in fact most people are statistically ignorant of it since statistically most people are not programmers. Conclusion: I am at a loss on what to search for to get the best additional results to cite, since they are making a technical claim and I want to know the truth and be able to prove it with citations like a real engineer/scientist, even if I am biased against god objects due to my personal experience with code that used them. Any assistance or citations would be deeply appreciated.

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• using isight camera in macbookpro(8,2) on ubuntu 12.04 virtualbox VM

  - by Kurt Spindler

  I'm having a lot of trouble using the built-in isight camera on my macbookpro8,2 (early 2011) from an ubuntu 12.04 virtual machine, run inside VirtualBox. The following is the log I get when I try to run guvcview ubuntu@ubuntu:~$ guvcview guvcview 1.5.3 ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.rear ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.center_lfe ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.side ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.surround71 ALSA lib setup.c:565:(add_elem) Cannot obtain info for CTL elem (MIXER,'IEC958 Playback Default',0,0,0): No such file or directory ALSA lib setup.c:565:(add_elem) Cannot obtain info for CTL elem (MIXER,'IEC958 Playback Default',0,0,0): No such file or directory ALSA lib setup.c:565:(add_elem) Cannot obtain info for CTL elem (MIXER,'IEC958 Playback Default',0,0,0): No such file or directory ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.hdmi ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.hdmi ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.modem ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.modem ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.phoneline ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.phoneline ALSA lib audio/pcm_bluetooth.c:1614:(audioservice_expect) BT_GET_CAPABILITIES failed : Input/output error(5) ALSA lib audio/pcm_bluetooth.c:1614:(audioservice_expect) BT_GET_CAPABILITIES failed : Input/output error(5) ALSA lib audio/pcm_bluetooth.c:1614:(audioservice_expect) BT_GET_CAPABILITIES failed : Input/output error(5) ALSA lib audio/pcm_bluetooth.c:1614:(audioservice_expect) BT_GET_CAPABILITIES failed : Input/output error(5) ALSA lib pcm_dmix.c:957:(snd_pcm_dmix_open) The dmix plugin supports only playback stream Cannot connect to server socket err = No such file or directory Cannot connect to server socket jack server is not running or cannot be started video device: /dev/video0 Init. FaceTime HD Camera (Built-in) (location: usb-0000:00:0b.0-1) { pixelformat = 'YUYV', description = 'YUV 4:2:2 (YUYV)' } { discrete: width = 160, height = 120 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 176, height = 144 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 320, height = 240 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 352, height = 288 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 640, height = 480 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 1280, height = 720 } Time interval between frame: 1/10, { pixelformat = 'MJPG', description = 'MJPEG' } { discrete: width = 960, height = 540 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 1024, height = 576 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 1280, height = 720 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { pixelformat = 'RGB3', description = 'RGB3' } { discrete: width = 160, height = 120 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 176, height = 144 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 320, height = 240 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 352, height = 288 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 640, height = 480 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 1280, height = 720 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 960, height = 540 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 1024, height = 576 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { pixelformat = 'BGR3', description = 'BGR3' } { discrete: width = 160, height = 120 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 176, height = 144 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 320, height = 240 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 352, height = 288 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 640, height = 480 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 1280, height = 720 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 960, height = 540 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 1024, height = 576 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { pixelformat = 'YU12', description = 'YU12' } { discrete: width = 160, height = 120 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 176, height = 144 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 320, height = 240 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 352, height = 288 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 640, height = 480 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 1280, height = 720 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 960, height = 540 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 1024, height = 576 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { pixelformat = 'YV12', description = 'YV12' } { discrete: width = 160, height = 120 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 176, height = 144 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 320, height = 240 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 352, height = 288 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 640, height = 480 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 1280, height = 720 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 960, height = 540 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, { discrete: width = 1024, height = 576 } Time interval between frame: 100/2997, 1/25, 1/24, 1/15, vid:05ac pid:8509 driver:uvcvideo checking format: 1196444237 VIDIOC_G_COMP:: Invalid argument compression control not supported fps is set to 1/25 drawing controls no codec detected for H264 no codec detected for MP3 - (lavc) Checking video mode 960x540@32bpp : OK Could not grab image (select timeout): Resource temporarily unavailable Could not grab image (select timeout): Resource temporarily unavailable Could not grab image (select timeout): Resource temporarily unavailable Could not grab image (select timeout): Resource temporarily unavailable Could not grab image (select timeout): Resource temporarily unavailable Could not grab image (select timeout): Resource temporarily unavailable Could not grab image (select timeout): Resource temporarily unavailable Could not grab image (select timeout): Resource temporarily unavailable Could not grab image (select timeout): Resource temporarily unavailable write /home/ubuntu/.guvcviewrc OK free controls cleaned allocations - 100% Closing portaudio ...OK Closing GTK... OK ubuntu@ubuntu:~$ Any help would be greatly appreciated. Only clue I have is that I initially was having problems, tried using the old method of fixing isights (involving installing isight-firmware-tools) before realizing that I just hadn't turned on the VM setting to allow the VM to access the webcam. :) Anyway, I wonder if installing that messed something up. However, I think this is a red herring because I've: shut down and turned back on the Mac, restarted the VM, tried a different VM (for which I never installed isight-firmware-tools, and created an entirely new ubuntu vm. All instances have had this problem. Similarly, other viewers, such as cheese, avplay, avconv have had all various kinds of errors.

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• xml file save/read error (making a highscore system for XNA game)

  - by Eddy

  i get an error after i write player name to the file for second or third time (An unhandled exception of type 'System.InvalidOperationException' occurred in System.Xml.dll Additional information: There is an error in XML document (18, 17).) (in highscores load method In data = (HighScoreData)serializer.Deserialize(stream); it stops) the problem is that some how it adds additional "" at the end of my .dat file could anyone tell me how to fix this? the file before save looks: <?xml version="1.0"?> <HighScoreData xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"> <PlayerName> <string>neil</string> <string>shawn</string> <string>mark</string> <string>cindy</string> <string>sam</string> </PlayerName> <Score> <int>200</int> <int>180</int> <int>150</int> <int>100</int> <int>50</int> </Score> <Count>5</Count> </HighScoreData> the file after save looks: <?xml version="1.0"?> <HighScoreData xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"> <PlayerName> <string>Nick</string> <string>Nick</string> <string>neil</string> <string>shawn</string> <string>mark</string> </PlayerName> <Score> <int>210</int> <int>210</int> <int>200</int> <int>180</int> <int>150</int> </Score> <Count>5</Count> </HighScoreData>> the part of my code that does all of save load to xml is: DECLARATIONS PART [Serializable] public struct HighScoreData { public string[] PlayerName; public int[] Score; public int Count; public HighScoreData(int count) { PlayerName = new string[count]; Score = new int[count]; Count = count; } } IAsyncResult result = null; bool inputName; HighScoreData data; int Score = 0; public string NAME; public string HighScoresFilename = "highscores.dat"; Game1 constructor public Game1() { graphics = new GraphicsDeviceManager(this); Content.RootDirectory = "Content"; Width = graphics.PreferredBackBufferWidth = 960; Height = graphics.PreferredBackBufferHeight =640; GamerServicesComponent GSC = new GamerServicesComponent(this); Components.Add(GSC); } Inicialize function (end of it) protected override void Initialize() { //other game code base.Initialize(); string fullpath =Path.Combine(HighScoresFilename); if (!File.Exists(fullpath)) { //If the file doesn't exist, make a fake one... // Create the data to save data = new HighScoreData(5); data.PlayerName[0] = "neil"; data.Score[0] = 200; data.PlayerName[1] = "shawn"; data.Score[1] = 180; data.PlayerName[2] = "mark"; data.Score[2] = 150; data.PlayerName[3] = "cindy"; data.Score[3] = 100; data.PlayerName[4] = "sam"; data.Score[4] = 50; SaveHighScores(data, HighScoresFilename); } } all methods for loading saving and output public static void SaveHighScores(HighScoreData data, string filename) { // Get the path of the save game string fullpath = Path.Combine("highscores.dat"); // Open the file, creating it if necessary FileStream stream = File.Open(fullpath, FileMode.OpenOrCreate); try { // Convert the object to XML data and put it in the stream XmlSerializer serializer = new XmlSerializer(typeof(HighScoreData)); serializer.Serialize(stream, data); } finally { // Close the file stream.Close(); } } /* Load highscores */ public static HighScoreData LoadHighScores(string filename) { HighScoreData data; // Get the path of the save game string fullpath = Path.Combine("highscores.dat"); // Open the file FileStream stream = File.Open(fullpath, FileMode.OpenOrCreate, FileAccess.Read); try { // Read the data from the file XmlSerializer serializer = new XmlSerializer(typeof(HighScoreData)); data = (HighScoreData)serializer.Deserialize(stream);//this is the line // where program gives an error } finally { // Close the file stream.Close(); } return (data); } /* Save player highscore when game ends */ private void SaveHighScore() { // Create the data to saved HighScoreData data = LoadHighScores(HighScoresFilename); int scoreIndex = -1; for (int i = 0; i < data.Count ; i++) { if (Score > data.Score[i]) { scoreIndex = i; break; } } if (scoreIndex > -1) { //New high score found ... do swaps for (int i = data.Count - 1; i > scoreIndex; i--) { data.PlayerName[i] = data.PlayerName[i - 1]; data.Score[i] = data.Score[i - 1]; } data.PlayerName[scoreIndex] = NAME; //Retrieve User Name Here data.Score[scoreIndex] = Score; // Retrieve score here SaveHighScores(data, HighScoresFilename); } } /* Iterate through data if highscore is called and make the string to be saved*/ public string makeHighScoreString() { // Create the data to save HighScoreData data2 = LoadHighScores(HighScoresFilename); // Create scoreBoardString string scoreBoardString = "Highscores:\n\n"; for (int i = 0; i<5;i++) { scoreBoardString = scoreBoardString + data2.PlayerName[i] + "-" + data2.Score[i] + "\n"; } return scoreBoardString; } when ill make this work i will start this code when i call game over (now i start it when i press some buttons, so i could test it faster) public void InputYourName() { if (result == null && !Guide.IsVisible) { string title = "Name"; string description = "Write your name in order to save your Score"; string defaultText = "Nick"; PlayerIndex playerIndex = new PlayerIndex(); result= Guide.BeginShowKeyboardInput(playerIndex, title, description, defaultText, null, null); // NAME = result.ToString(); } if (result != null && result.IsCompleted) { NAME = Guide.EndShowKeyboardInput(result); result = null; inputName = false; SaveHighScore(); } } this where i call output to the screen (ill call this in highscores meniu section when i am done with debugging) spriteBatch.DrawString(Font1, "" + makeHighScoreString(),new Vector2(500,200), Color.White); }

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• BIP and Mapviewer Mash Up I

  - by Tim Dexter

  I was out in Yellowstone last week soaking up various wildlife and a bit too much rain ... good to be back until the 95F heat yesterday. Taking a little break from the Excel templates; the dev folks are planing an Excel patch in the next week or so that will add a mass of new functionality. At the risk of completely mis leading you I'm going to hang back a while. What I have written so far holds true and will continue to do so. This week, I have been mostly eating 'mapviewer' ... answers on a post card please, TV show and character. I had a request to show how BIP can call mapviewer and render a dynamic map in an output. So I hit the books and colleagues for some answers. Mapviewer is Oracle's geographic information system, hereby known as GIS. I use it a lot in our BIEE demos where the interaction with the maps is very impressive. Need a map of California and its congressional districts? I have contacts; Jerry and David with their little black box of maps. Once in my possession I can build highly interactive, clickable maps that allow the user to drill into more information using a very friendly interface driving BIEE content and navigation. But what about maps in BIP output? Bryan Wise, who has written some articles on this blog did some work a while back with the PL/SQL API interface. The extract for the report called a function that in turn called the mapviewer server, passing a set of mapping requirements, it then returned a URL to a cached copy of that map. Easy to then have BIP render that image. Thats still very doable. You need to install a couple of packages and then load the mapviewer java APIs into the database. Then you can write your function to the APIs. A little involved? Maybe, but the database is doing all the heavy lifting for you. I thought I would investigate another method for getting the maps back into BIP. There is a URL interface you can call, this involves building an XML message to be passed to the mapviewer server. It's pretty straightforward to use on the mapviewer side. On the BIP side things are little more tricksy. After some unexpected messing about I finally got the ubiquitous Hello World map to render using the URL method. Not the most exciting map in the world, lots of ocean and a rather long URL to get it to render. http://127.0.0.1:9704/mapviewer/omserver?xml_request=%3Cmap_request%20title=%22Hello%20World%22%20datasource=%22cagis%22%20format=%22GIF_STREAM%22/%3E Notice all of the encoding in the URL string to handle the spaces, quotes, etc. All necessary to get BIP to make the call to the mapviewer server correctly without truncating the URL if it hits a real space rather than a %20. With that in mind constructing the URL was pretty simple. I'm not going to get into the content of the URL too much, for that you need to bone up on the mapviewer XML API. Check out the home page here and the documentation here. To make the template portable I used the standard CURRENT_SERVER_URL parameter from the BIP server and declared that in my template. <?param@begin:CURRENT_SERVER_URL;'myserver'?> Ignore the 'myserver', that was just a dummy value for testing at runtime it will resolve to: 'http://yourserver:port/xmlpserver' Not quite what we need as mapviewer has its own server path, in my case I needed 'mapviewer/omserver?xml_request=' as the fixed path to the mapviewer request URL. A little concatenation and substringing later I came up with <?param@begin:mURL;concat(substring($CURRENT_SERVER_URL,1,22),'mapviewer/omserver?xml_request=')?> Thats the basic URL that I can then build on. To get the Hello World map I need to add the following: <map_request title="Hello World" datasource="cagis" format="GIF_STREAM"/> Those angle brackets were the source of my headache, BIPs XSLT engine was attempting to process them rather than just pass them. Hok Min to the rescue ... again. I owe him lunch when I get out to HQ again! To solve the problem, I needed to escape all the characters and white space and then use native XSL to assign the string to a parameter. <xsl:param xdofo:ctx="begin"name="pXML">%3Cmap_request%20title=%22Hello%20World%22 %20datasource=%22cagis%22%20format=%22GIF_STREAM%22/%3E</xsl:param> I did not need to assign it to a parameter but I felt that if I were going to do anything more serious than Hello World like plotting points of interest on the map. I would need to dynamically build the URL, so using a set of parameters or variables that I then concatenated would be easier. Now I had the initial server string and the request all I then did was combine the two using a concat: concat($mURL,$pXML) Embedding that into an image tag: <fo:external-graphic src="url({concat($mURL,$pXML)})"/> and I was done. Notice the curly braces to get the concat evaluated prior to the image call. As you will see next time, building the XML message to go onto the URL can get quite complex but I have used it with some data. Ultimately, it would be easier to build an extension to BIP to handle the data to be plotted, it would then build the XML message, call mapviewer and return a URL to the map image for BIP to render. More on that next time ...

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