Question

I’ve set up a WCF web service to be called from my web site. It’s working great, but if I request a large amount of data (not sure on the size, but it’s easily 3-4 times larger than the “standard” data I’m returning), Cassini (Visual Studio Web Server) just closes the response without sending anything– no error or anything. Nothing in event log. Just nada.

I’m a newbie to WCF, but I know there must be some configuration option I’m missing here (like a message/response max size/limit) that solves my problem. Here’s what my web.config section looks like:

<system.serviceModel>   
  <serviceHostingEnvironment aspNetCompatibilityEnabled="true" />   
   <behaviors>
   <endpointBehaviors>
    <behavior name="securetmhAspNetAjaxBehavior">
     <enableWebScript />
    </behavior>
   </endpointBehaviors>
   <serviceBehaviors>
    <behavior name="tmhsecureBehavior">
     <serviceMetadata httpGetEnabled="false" />
     <serviceDebug includeExceptionDetailInFaults="false" />
    </behavior>
   </serviceBehaviors>
  </behaviors>
  <services>
   <service name="securetmh">
    <endpoint address="" behaviorConfiguration="securetmhAspNetAjaxBehavior" binding="webHttpBinding" contract="securetmh" />
   </service>
  </services>
 </system.serviceModel>

Any help would be appreciated.

Answer 1

For security reasons, WCF limits the data returned by a service call to 64 K by default.

You can obviously change that – there’s a gazillion of entries to tweak. See this sample config here:

  <system.serviceModel>
    <bindings>
      <webHttpBinding>
        <binding name="customWebHttp"
                 maxBufferPoolSize="256000"
                 maxReceivedMessageSize="256000"
                 maxBufferSize="256000">
          <readerQuotas 
            maxArrayLength="256000"
            maxStringContentLength="256000"/>
        </binding>
      </webHttpBinding>
    </bindings>
    <services>
      <service name="YourService">
        <endpoint name="test"
                  address="....."
                  binding="webHttpBinding"
                  bindingConfiguration="customWebHttp"
                  contract="IYourService" />
      </service>
    </services>
  </system.serviceModel>

You need to define a custom binding configuration based on the webHttpBinding, and you can tweak all those various settings – I set them all to 256K (instead of 64K).

Hope this helps!