Versioning and Continuous Integration with project settings files

by | May 22, 2010 | BizTalk Community Blogs via Syndication

I came across something which was a bit of a pain in the bottom the other week.

Our scenario was that we had implemented a helper style assembly which had some custom configuration implemented through the project settings. I’m sure most of you are familiar with this where you end up with a settings file which is viewable through the C# project file and you can configure some basic settings.

The settings are embedded in the assembly during compilation to be part of a DefaultValue attribute. You have the ability to override the settings by adding information to your app.config and if the app.config doesn’t override the settings then the embedded default is used.

All normal C# stuff so far

Where our pain started was when we implement Continuous Integration and we wanted to version all of this from our build. What I was finding was that the assembly was versioned fine but the embedded default value was maintaining the non CI build version number.

I ended up getting this to work by using a build task to change the version numbers in the following files:

  • App.config
  • Settings.settings
  • Settings.designer.cs

I think I probably could have got away with just the settings.designer.cs, but wanted to keep them all consistent incase we had to look at the code on the build server for some reason.

I think the reason this was painful was because the settings.designer.cs is only updated through Visual Studio and it writes out the code to this file including the DefaultValue attribute when the project is saved rather than as part of the compilation process. The compile just compiles the already existing C# file.

As I said we got it working, and it was a bit of a pain. If anyone has a better solution for this I’d love to hear it

Testing Reference Data Mappings

by | May 22, 2010 | BizTalk Community Blogs via Syndication

Background

Mapping reference data is one of the common scenarios in BizTalk development and its usually a bit of a pain when you need to manage a lot of reference data whether it be through the BizTalk Cross Referencing features or some kind of custom solution.

I have seen many cases where only a couple of the mapping conditions are ever tested.

Approach

As usual I like to see these things tested in isolation before you start using them in your BizTalk maps so you know your mapping functions are working as expected.

This approach can be used for almost all of your reference data type mapping functions where you can take advantage of MSTests data driven tests to test lots of conditions without having to write millions of tests.

Walk Through

Rather than go into the details of this here, I’m going to call out to one of my colleagues who wrote a nice little walk through about using data driven tests a while back.

Check out Callum’s blog: http://callumhibbert.blogspot.com/2009/07/data-driven-tests-with-mstest.html

May 20th Links: ASP.NET MVC, ASP.NET, .NET 4, VS 2010, Silverlight

by | May 21, 2010 | BizTalk Community Blogs via Syndication

Here is the latest in my link-listing series.  Also check out my VS 2010 and .NET 4 series and ASP.NET MVC 2 series for other on-going blog series I’m working on.

[In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu]

ASP.NET MVC

  • How to Localize an ASP.NET MVC Application: Michael Ceranski has a good blog post that describes how to localize ASP.NET MVC 2 applications.

  • ASP.NET MVC with jTemplates Part 1 and Part 2: Steve Gentile has a nice two-part set of blog posts that demonstrate how to use the jTemplate and DataTable jQuery libraries to implement client-side data binding with ASP.NET MVC.

  • How to Configure VS 2010 Code Coverage for ASP.NET MVC Unit Tests: Visual Studio enables you to calculate the “code coverage” of your unit tests.  This measures the percentage of code within your application that is exercised by your tests – and can give you a sense of how much test coverage you have.  Gunnar Peipman demonstrates how to configure this for ASP.NET MVC projects.

  • Shrinkr URL Shortening Service Sample: A nice open source application and code sample built by Kazi Manzur that demonstrates how to implement a URL Shortening Services (like bit.ly) using ASP.NET MVC 2 and EF4.  More details here.

  • Creating RSS Feeds in ASP.NET MVC: Damien Guard has a nice post that describes a cool new “FeedResult” class he created that makes it easy to publish and expose RSS feeds from within ASP.NET MVC sites.

  • Using the FCKEditor with ASP.NET MVC: Quick blog post that describes how to use FCKEditor – an open source HTML Text Editor – with ASP.NET MVC.

ASP.NET

  • Integrating Twitter into an ASP.NET Website using OAuth: Scott Mitchell has a nice article that describes how to take advantage of Twiter within an ASP.NET Website using the OAuth protocol – which is a simple, secure protocol for granting API access.

.NET 4

  • Entity Framework 4 Video Series: Julie Lerman has a nice, free, 7-part video series on MSDN that walks through how to use the new EF4 capabilities with VS 2010 and .NET 4.  I’ll be covering EF4 in a blog series that I’m going to start shortly as well.

  • Getting Lazy with System.Lazy: System.Lazy and System.Lazy<T> are new features in .NET 4 that provide a way to create objects that may need to perform time consuming operations and defer the execution of the operation until it is needed.  Derik Whittaker has a nice write-up that describes how to use it.

  • LINQ to Twitter: Nifty open source library on Codeplex that enables you to use LINQ syntax to query Twitter.

Visual Studio 2010

  • Using Intellitrace in VS 2010: Chris Koenig has a nice 10 minute video that demonstrates how to use the new Intellitrace features of VS 2010 to enable DVR playback of your debug sessions.

  • How to maintain control of your code using Layer Diagrams: Another great blog post by Jennifer Marsman that demonstrates how to setup a “layer diagram” within VS 2010 to enforce clean layering within your applications.  This enables you to enforce a compiler error if someone inadvertently violates a layer design rule.

  • Collapse Selection in Solution Explorer Extension: Useful VS 2010 extension that enables you to quickly collapse “child nodes” within the Visual Studio Solution Explorer.  If you have deeply nested project structures this extension is useful.

Silverlight and Windows Phone 7

Hope this helps,

Scott

P.S. If you haven’t already, check out this month’s "Find a Hoster” page on the www.asp.net website to learn about great (and very inexpensive) ASP.NET hosting offers.

Using NServiceBus behind a custom web service

by | May 20, 2010 | BizTalk Community Blogs via Syndication

In this post I’d like to talk about an architecture scenario we had recently and how we were able to utilise NServiceBus to help us address this problem.

Scenario

Cognos is a reporting system used by one of my clients. A while back we developed a web service fa%u00e7ade to allow line of business applications to be able to access reports from Cognos to support their various functions.

The service was intended to provide access to reports which were quick running reports or pre-generated reports which could be accessed real-time on demand. One of the key aims of the web service was to provide a simple generic interface to allow applications to get any report without needing to worry about the complex .net SDK for Cognos.

The web service also supported multi-hop kerberos delegation so that report data could be accesses under the context of the end user.

This service was working well for a period of time.

The Problem

The problem we encountered was that reports were now also required to be available to batch processes. The original design was optimised for low latency so users would enjoy a positive experience, however when the batch processes started to request 250+ concurrent reports over an extended period of time you can begin to imagine the sorts of problems that come into play. The key problems this new scenario caused are:

  1. Users may be affected and the latency of on demand reports was significantly slower
  2. The Cognos infrastructure was not scaled sufficiently to be able to cope with these long peaks of load

From a cost perspective it just isn’t feasible to scale the Cognos infrastructure to be able to handle the load when it is only for a couple of hour window each night. We really needed to introduce a second pattern for accessing this service which would support high through-put scenarios.

We also had little control over the batch process in terms of being able to throttle its load. We could however make some changes to the way it accessed the reports.

The Approach

My idea was to introduce a throttling mechanism between the Web Service Fa%u00e7ade and Cognos. This would allow the batch processes to push reports requests hard at the web service which we were confident the web service can handle. The web service would then queue these requests and process them behind the scenes and make a call back to the batch application to provide the report once it had been accessed.

In terms of technology we had some limitations because we were not able to use WCF or IIS7 where the MSMQ-Activated WCF services could have helped, but we did have MSMQ as an option and I thought NServiceBus could do just the job to help us here.

The flow of how this would work was as follows:

  1. The batch applications would send a request for a report to the web service
  2. The web service uses NServiceBus to send the message to a Queue
  3. The NServiceBus Generic Host is running as a windows service with a message handler which subscribes to these messages
  4. The message handler gets the message, accesses the report from Cognos
  5. The message handler calls back to the original batch application, this is decoupled because the calling application provides a call back url
  6. The report gets into the batch application and is processed as normal

This approach looks something like the below diagram:

The key points are an application wanting to take advantage of the batch driven reports needs to do the following:

  • Implement our call back contract
  • Make a call to the service providing a call back url
  • Provide a correlation ID so it knows how to tie each response back to its request

What does NServiceBus offer in this solution

So this scenario is not the typical messaging service bus type of solution people implement with NServiceBus, but it did offer the following:

  • Simplified interaction with MSMQ
  • Offered the ability to configure the number of processes working through the queue so we could find a balance between load on Cognos versus the applications end to end processing time
  • NServiceBus offers retries and a way to manage failed messages
  • NServiceBus offers a high availability setup

The simple thing is that NServiceBus gave us the platform to build the solution on. We just implemented a message handler which functionally processed a message and we could rely on NServiceBus to do all of the hard work around managing the queues and all of the lower level things that would have took ages to write to any kind of robust level.

Conclusion

With this approach we were able to deal with a fairly significant performance issue with out too much rework. Hopefully this write up gives people some insight into ideas on how to leverage the excellent NServiceBus framework to help solve integration and high through-put scenarios.

BizTalk Server 2010 Public Beta and Windows Server AppFabric RC now available

by | May 20, 2010 | BizTalk Community Blogs via Syndication

In case you missed the Application Infrastructure Virtual launch today (you can go watch it on demand), Microsoft has made available:

  • BizTalk Server 2010 beta, get it here (note that the ESB Toolkit 2.1 beta is on that page also)
  • The Windows Server AppFabric release candidate, get it here

You can read the official announcement on the BizTalk team blog, and also here at the Endpoint blog.

Make sure you check out the new mapper functionality in the BizTalk, it ROCKS! What seems like a simple problem quick deteriorates into some very complex UI issues, and the team has really done a great job in providing a UI that nicely addresses those challenges, and more.

One of the coolest features of the mapper is the new “indicate match” capability. In the screen shot below, I right-clicked the “PO403” node, the mapper thought “PONumber” was the best match, but that the other “PONumber”  and “PODate” were also possible matches. Very very nice!!

 

 

Happy downloading!!