I recently worked on a POC which had me spinning up an EDIFACT/AS2 exchange based on both BizTalk Server and MABS (Microsoft Azure BizTalk Server) and comparing the experiences.  Seeing as this was my first time dealing with AS2 (EDIFACT was already an old friend) the very first thing I worked on was finding a means of sending messages to the AS2 onramps.

I found a few open source programs that would let me submit AS2 messages but I decided I wanted to do this programmatically instead via BizUnit 4.0 so I had easily repeatable scenarios, which I could easily re-test across BizTalk Server and MABS.  Matt Frear has written a good post on how to send messages via AS2 using .NET, and I decided I was going to convert this into a BizUnit test step (with his blessing).

You can find the source code for the AS2SendTestStep here, or if you just want to download the assembly then you can do so here.

The test step support the below features.

  • Supports BizTalk Server and MABS (and theoretically other AS2 server products, but I haven’t tested any others).
  • Supports BizUnit data loaders which means that if you have many tests which require only slight variations to input messages then you don’t need to keep multiple copies of input files. You can just have a single base file and use a relevant DataLoader class to manipulate the stream as it is being read.
  • Supports signing and encrypting outbound messages.
  • Supports optional synchronous MDNs and allows you to validate them.
  • Logs decrypted MDN messages to the test execution report.

Usage tips are below.

  • You will need to reference the BizUnit.AS2TestSteps.dll assembly and the BizUnit.dll assembly provided by the BizUnit 4.0 framework.
  • Select an input file directly by supplying the file name into the InputFileLocation property or supply a BizUnit DataLoader (which allows you to manipulate the file as you read it in) in the InputFileLoader property.
  • Encrypt the outbound message – you will need a copy of the public key certificate and will need to supply the file path to it in the EncryptionCertificateFileLocation property.
  • Sign the outbound message – you will need a copy of the private key certificate and will need to know the password.  You will need to supply the path to the certificate to the SigningCertificateFileLocation property and the password to the SigningCertificatePassword property.
  • Supports setting AS2From and AS2To headers via the As2From and As2To properties.
  • Supports the use of a proxy server by setting appropriate values to the Ps property which allows you to supply the proxy server URL, and if required credentials as well.
  • Allows you to set the subject HTTP header by setting the As2FileName property.
  • Allows you to set the URL to post the request to by setting the Url property.
  • Allows you to override the default timeout of 20 seconds by setting the TimeoutMilliseconds property.
  • Allows you to run BizUnit substeps against the decrypted response message in case you want to validate it by suppying substeps into the SubSteps property.

An example test which sends an EDIFACT message to BizTalk Server (using a proxy server) and runs some regular expressions against the synchronous MDN response is below.  Note that the RegexValidationStep in use here is not part of the BizUnit framework and is proprietary so sorry I can’t share that.

var testCase = new BizUnit.Xaml.TestCase();

var as2TestStep = new AS2SendTestStep();

as2TestStep.As2From = "FABRIKAM";

as2TestStep.As2To = "CONTOSO";

as2TestStep.EncryptionCertificateFileLocation = @"c:\host.cer";

as2TestStep.As2FileName = "EFACT_D95B_CODECO_output.txt";

as2TestStep.InputFileLocation = @"c:\temp\EFACT_D95B_CODECO_output.txt";

as2TestStep.SigningCertificateFileLocation = @"c:\fab.pfx";

as2TestStep.SigningCertificatePassword = "test";

as2TestStep.TimeoutMilliseconds = 20000;

as2TestStep.Url = "http://localhost/AS2Receive/BTSHTTPReceive.dll";

WebTestPlugins.AS2Helpers.ProxySettings ps = new WebTestPlugins.AS2Helpers.ProxySettings();

ps.Name = "http://proxyserver.test.co.nz";

as2TestStep.Ps = ps;

var regexValidationStep = new RegexValidationStep();

regexValidationStep._RegexDefintion.Add(new RegexDefinition("Content-Type: message/disposition-notification"));

regexValidationStep._RegexDefintion.Add(new RegexDefinition("Disposition: automatic-action/MDN-sent-automatically; processed"));

regexValidationStep._RegexDefintion.Add(new RegexDefinition("Final-Recipient: rfc822; CONTOSO"));



var bizUnitTest = new BizUnit.BizUnit(testCase);


And below is a screenshot of the test execution results.  Note that the MDN text is logged here, and you can see the regular expressions being evaluated against the MDN as well.


You can of course take your own test steps much further by validating that BizTalk/MABS has consumed the file and written the message to its target destination, be it a SQL database or a file system folder etc… using the out of the box BizUnit test steps or your own custom ones.

The test step doesn’t currently support compression.  If anyone can point me towards any good documentation on compressing AS2 messages in C# then I might try to include that.

Any other suggestions are welcome.