Enterprise Apps in Windows Azure - Calling the Internet Service Bus (.NET Services from Azure)

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In the last days I implemented a typical enterprise cloud app on Windows Azure.

WARNING: Beyond this step no Hello World scenarios! Watch your step!

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The scenario is based on the famous TimeTracker SL3 Sample which you can find in the Expression Gallery. It is a vendor management system where I can track my vendors time and i can approve the tasks and then have them send over to SAP to create a Purchase Order.

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The Data Model is quite simple, too and done with Entity Framework over SQL Azure.

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In 2010 it is nice that you can generate DDL from the Diagram using a right click and select generate database from model. I used that and modified a bit of the code to work in SQL Azure.

With help of the SQL Azure Data Explorer you can actually see the data from within
VS2010

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Based on the time-tracker sample it was quite easy to adjust the connection string to point to SQL Azure and add a .xap mapping for SL to the web.config. Then the Time-Tracker already runs smoothly on Windows Azure. Also I added support for SSL and SSO on Windows Azure

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Now the reason why i am blogging: I found it quite easy to use the Echoing Sample from the .NET Services SDK as a basis to add communication from my WebRole to my ERP system. However this seemed to work only on my machine and in the simulator.

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After quite some time I found what was going wrong when accessing the Service Bus from within a WebRole in Azure (when deployed) using NetTcpBinding. I got Configuration Binding Extension not found.

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I then asked the .NET Services Team what is wrong and it turns out that:

To use the config elements in Azure you need to move the extensions into your web.config. To find them, take a look at your machine.config file. You’ll have to replicate the system.serviceModel extensions that reference the Microsoft.ServiceBus assembly into your web.config that you deploy into Azure. We haven’t made a cut & paste snippet for that yet, but we really should.

If this Problem did not occur i might not have blogged about the whole story. So it seems also to have its good side. ;-).

Now all works fine also in the Cloud ;-)

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Happy Cloud Computing!

Tim