Question

I am using WCF Data Service’s processing pipeline do some message notification set-up prior to processing the change sets. I am using batch mode to submit my changes. I am testing a scenario where the notification service is not running, and therefore we throw a specific message prior to the change set processing.

Here’s how my code is set up

ProcessingPipeline.ProcessingChangeset += ProcessingChangeset;

You can easily mimic my error as follows:

private void ProcessingChangeset(object sender, EventArgs e)
{
    throw new Exception("Some Specific Messsage");
}

When I run my test, I do not get the “Some Specific Message” exception that I expect. Instead I receive:

System.Data.Services.Client.DataServiceRequestException: An error
occurred while processing this request. —>
System.InvalidOperationException: Missing change set boundary
delimiter. Please make sure that change set boundary delimiter is
specified to mark the end of a change set.

I inspected the test response using Fiddler to see the contents.

--batchresponse_f158ae30-03c4-479e-8dda-a9129d2a1036
Content-Type: multipart/mixed; boundary=changesetresponse_92c24e82-47ad-43a2-b3e2-79d9e5ada261

--batchresponse_f158ae30-03c4-479e-8dda-a9129d2a1036
Content-Type: application/http
Content-Transfer-Encoding: binary

HTTP/1.1 500 Internal Server Error
DataServiceVersion: 1.0;
Content-Type: application/xml

<?xml version="1.0" encoding="utf-8" standalone="yes"?>
<error xmlns="http://schemas.microsoft.com/ado/2007/08/dataservices/metadata">
  <code></code>
  <message xml:lang="en-US">An error occurred while processing this request.</message>
  <innererror>
    <message>Some Specific Message</message>
    <type>System.Exception</type>
    <stacktrace>   at SM.Service.BaseService`1.ProcessingChangeset(Object sender, EventArgs e) in C:\svn\gr-core\ServiceManager\trunk\SM.Service\BaseService.cs:line 71&#xD;
   at System.Data.Services.DataServiceProcessingPipeline.InvokeProcessingChangeset(Object sender, EventArgs e)&#xD;
   at System.Data.Services.DataService`1.BatchDataService.HandleBatchContent(Stream responseStream)</stacktrace>
  </innererror>
</error>
--changesetresponse_92c24e82-47ad-43a2-b3e2-79d9e5ada261
Content-Type: application/http
Content-Transfer-Encoding: binary

HTTP/1.1 204 No Content
Content-ID: 2
Cache-Control: no-cache
DataServiceVersion: 1.0;


--changesetresponse_92c24e82-47ad-43a2-b3e2-79d9e5ada261--
--batchresponse_f158ae30-03c4-479e-8dda-a9129d2a1036--

It looks like the duplicate batchresponse entries may be the issue. Has anyone encountered this or found a work around so the appropriate message can be returned?

Our other functional tests that have errors in the change set processing (not prior) all return the expected messages.

Answer 1

This does indeed look like a bug. I checked on our recent builds and the behavior is definitely better (no duplicate boundaries, but a correct error response as far as I can tell).
You could try the latest CTP which might have this fixed here: http://blogs.msdn.com/b/astoriateam/archive/2011/10/13/announcing-wcf-data-services-oct-2011-ctp-for-net-4-and-silverlight-4.aspx