对ServiceStack的PUT / POST请求挂起

Question

When I make POST and PUT requests to my ServiceStack services (running standalone with an HTTP listener at the moment) I sometimes find that the request will work, and sometimes my client (HTTPie) will hang. After a while I'll see some info in the Output window in Visual Studio:-

A first chance exception of type 'System.Net.HttpListenerException' occurred in System.dll
A first chance exception of type 'System.Runtime.Serialization.SerializationException' occurred in ServiceStack.dll
A first chance exception of type 'System.Net.HttpListenerException' occurred in System.dll
A first chance exception of type 'System.Net.HttpListenerException' occurred in ServiceStack.dll
A first chance exception of type 'System.Net.HttpListenerException' occurred in ServiceStack.dll
A first chance exception of type 'System.Runtime.Serialization.SerializationException' occurred in ServiceStack.dll
A first chance exception of type 'System.ObjectDisposedException' occurred in System.dll

I managed to enable the built-in logging in ServiceStack and it gave more details:-

ERROR: Error occured while Processing Request: Could not deserialize 'application/json; charset=utf-8' 
   request using WebServices.Dto.Country'
Error: System.Net.HttpListenerException (0x80004005): The I/O operation has been aborted because of either
    a thread exit or an application request
  at System.Net.HttpRequestStream.Read(Byte[] buffer, Int32 offset, Int32 size)
  at System.IO.StreamReader.ReadBuffer()
  at System.IO.StreamReader.ReadToEnd()
  at ServiceStack.Text.JsonSerializer.DeserializeFromStream(Type type, Stream stream) in C:\src\ServiceStack.Text\
   src\ServiceStack.Text\JsonSerializer.cs:line 164
  at ServiceStack.ServiceModel.Serialization.JsonDataContractDeserializer.DeserializeFromStream(Type type, Stream 
   stream) in C:\src\ServiceStack\src\ServiceStack.Common\ServiceModel\Serialization\JsonDataContractDeserializer.cs:line 86
  at ServiceStack.WebHost.Endpoints.Support.EndpointHandlerBase.CreateContentTypeRequest(IHttpRequest httpReq, 
   Type requestType, String contentType) in C:\src\ServiceStack\src\ServiceStack\WebHost.Endpoints\Support\
   EndpointHandlerBase.cs:line 100, 
Exception: Could not deserialize 'application/json; charset=utf-8' request using WebServices.Dto.Country'
Error: System.Net.HttpListenerException (0x80004005): The I/O operation has been aborted because of either a thread
   exit or an application request
  at System.Net.HttpRequestStream.Read(Byte[] buffer, Int32 offset, Int32 size)
  at System.IO.StreamReader.ReadBuffer()
  at System.IO.StreamReader.ReadToEnd()
  at ServiceStack.Text.JsonSerializer.DeserializeFromStream(Type type, Stream stream) in C:\src\ServiceStack.Text\src\
   ServiceStack.Text\JsonSerializer.cs:line 164
  at ServiceStack.ServiceModel.Serialization.JsonDataContractDeserializer.DeserializeFromStream(Type type, Stream 
   stream) in C:\src\ServiceStack\src\ServiceStack.Common\ServiceModel\Serialization\JsonDataContractDeserializer.cs:line 86
  at ServiceStack.WebHost.Endpoints.Support.EndpointHandlerBase.CreateContentTypeRequest(IHttpRequest httpReq, 
   Type requestType, String contentType) in C:\src\ServiceStack\src\ServiceStack\WebHost.Endpoints\Support\EndpointHandlerBase.cs:line 100
ERROR: Could not WriteTextToResponse: An operation was attempted on a nonexistent network connection, Exception: 
   An operation was attempted on a nonexistent network connection
ERROR: Could not WriteTextToResponse: An operation was attempted on a nonexistent network connection, Exception: 
   An operation was attempted on a nonexistent network connection
INFO: Failed to write error to response: {0}, Exception: An operation was attempted on a nonexistent network connection

I am making my test requests like this:-

http --json post "http://localhost:1337/countries/" DefaultHouse_Id=2 Name=Denmark

This exact attempt works some time and fails others. I'm using the latest ServiceStack from NuGet with .NET4 and VS 2010. It appears that the request does not reach my own code at all.

Does anyone know what could cause this, or how I can debug it?

Edit: Not sure if it's related or not, but sometimes I also get this:-

{

"ResponseStatus":{

 "ErrorCode":"TypeLoadException",
 "Message":"Could not load type 'ServiceStack.ServiceInterface.HttpRequestApplyToExtensions' from assembly 'ServiceStack.ServiceInterface, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'.",
"StackTrace":"   at RulesLayer.AuditFilterAttribute.Execute(IHttpRequest req, IHttpResponse res, Object requestDto)\n   at     ServiceStack.ServiceInterface.RequestFilterAttribute.RequestFilter(IHttpRequest req, IHttpResponse res, Object requestDto) in C:\\src\\ServiceStack\\src\\ServiceStack.ServiceInterface\\RequestFilterAttribute.cs:line 41\n   at ServiceStack.WebHost.Endpoints.EndpointHost.ApplyRequestFilters(IHttpRequest httpReq, IHttpResponse httpRes, Object requestDto) in C:\\src\\ServiceStack\\src\\ServiceStack\\WebHost.Endpoints\\EndpointHost.cs:line 303\n   at ServiceStack.WebHost.Endpoints.RestHandler.ProcessRequest(IHttpRequest httpReq, IHttpResponse httpRes, String operationName) in C:\\src\\ServiceStack\\src\\ServiceStack\\WebHost.Endpoints\\RestHandler.cs:line 63"
}

}

Answer 1

It appears AVG Anti-Virus Business was the culprit. I knew I hated anti-virus software for a reason!

I discovered that the code worked fine on another machine, which told me that it was something specific to my dev box setup. I tried stripping the machine back to bare minimum, removing unused software, VS extensions, plugins etc. I tried both IIS Express and self-hosted modes for ServiceStack. I tried moving my code out of Dropbox. Nothing made any difference.

When I finally disabled AVG, the problem just vanished and several hours later it's still working perfectly.

Answer 2

To debug, nothing beats downloading the project source code and debugging the framework source code itself. I recommend trying to replicate this behavior in an integration test so we can find out what's causing it. See ServiceStack's http listener integration tests for examples on how to do this.

To enable logging in ServiceStack you just need set the log factory to be the provider of your choice before you start/initialize the AppHost.

LogManager.LogFactory = new ConsoleLogFactory(typeof(Program));