If HttpResponseMessage is disposed next request fails

[hecsalazar]

It would be nice to have an option to make it return a new HttpResponseMessage on every call.
I have a code that disposes the message after extracting the contents and unit tests broke because the response instance gets disposed inside the mock.

System.ObjectDisposedException occurred
Message: Exception thrown: 'System.ObjectDisposedException' in System.Net.Http.dll
Additional information: Cannot access a disposed object.

[richardszalay]

Can you provide a reproducible example? The following succeeds for me:

var mockHttp = new MockHttpMessageHandler();
            
var mockedRequest = mockHttp.When("/path");
mockedRequest.Respond(req => new StringContent("test", Encoding.UTF8, "text/plain"));

var request = new HttpRequestMessage(HttpMethod.Post, "http://www.tempuri.org/path?apple=red&pear=green")
{
    Content = new StringContent("testing")
};

string contentA;
using (var responseA = mockedRequest.SendAsync(request, CancellationToken.None).Result)
{
    contentA = responseA.Content.ReadAsStringAsync().Result;
}

string contentB;
using (var responseB = mockedRequest.SendAsync(request, CancellationToken.None).Result)
{
    contentB = responseB.Content.ReadAsStringAsync().Result;
}

[richardszalay]

Hi there, I haven't heard back from you on this issue for a while so I'm going to close it. Please feel free to create a new issue if you manage to create a reproducible example.

[hecsalazar]

Sorry for the delay, I've been in a big rush the past weeks I'll try to send you a code to reproduce by the end of the week

…

On Tue, Jun 6, 2017 at 7:58 PM Richard Szalay ***@***.***> wrote: Hi there, I haven't heard back from you on this issue for a while so I'm going to close it. Please feel free to create a new issue if you manage to create a reproducible example. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#33 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AKQTjWFiN4q9eAc-2wrKl8Ult2BYtGDQks5sBeeQgaJpZM4Nczsx> .

[richardszalay]

I'm going to close this issue due to lack of activity. If you're able to create a "MCV" example, I'm more than happy to dive deeper and fix the underlying issue.

[chengbo]

Hello, I have a reproducible example below

using System.Net.Http;
using RichardSzalay.MockHttp;

namespace MockHttpClient
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Hello World!");

            var mockHandler = new MockHttpMessageHandler();
            mockHandler.When("*").Respond("text/html", "");

            var regularHandler = new HttpClientHandler();
            var repository = new Repository(mockHandler);
            // Use below handler works fine.
            // var repository = new Repository(regularHandler);
            Console.WriteLine(repository.Get1());
            Console.WriteLine(repository.Get2());
        }
    }

    class Repository
    {
        private readonly HttpMessageHandler handler;

        public Repository(HttpMessageHandler handler)
        {
            this.handler = handler;
        }

        public string Get1()
        {
            HttpClient client = new HttpClient(handler, false);
            return client.GetStringAsync("https://www.google.com").Result;
        }

        public string Get2()
        {
            HttpClient client = new HttpClient(handler, false);
            return client.GetStringAsync("https://github.com").Result;
        }
    }
}

Below is the output.

/tmp/MockHttpClient » dotnet run .                                                                                           chengbo@Bo-MBP
Hello World!


Unhandled Exception: System.AggregateException: One or more errors occurred. (Cannot access a disposed object.
Object name: 'System.Net.Http.HttpResponseMessage'.) ---> System.ObjectDisposedException: Cannot access a disposed object.
Object name: 'System.Net.Http.HttpResponseMessage'.
   at System.Net.Http.HttpResponseMessage.CheckDisposed()
   at System.Net.Http.HttpResponseMessage.set_RequestMessage(HttpRequestMessage value)
   at RichardSzalay.MockHttp.MockHttpMessageHandler.<>c__DisplayClass13_0.<SendAsync>b__1(Task`1 resp)
   at System.Threading.Tasks.ContinuationResultTaskFromResultTask`2.InnerInvoke()
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.Tasks.Task.ExecuteWithThreadLocal(Task& currentTaskSlot)
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1.ConfiguredTaskAwaiter.GetResult()
   at System.Net.Http.HttpClient.<FinishSendAsyncUnbuffered>d__59.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1.ConfiguredTaskAwaiter.GetResult()
   at System.Net.Http.HttpClient.<GetStringAsyncCore>d__27.MoveNext()
   --- End of inner exception stack trace ---
   at System.Threading.Tasks.Task`1.GetResultCore(Boolean waitCompletionNotification)
   at MockHttpClient.Repository.Get2() in /private/tmp/MockHttpClient/Program.cs:line 42
   at MockHttpClient.Program.Main(String[] args) in /private/tmp/MockHttpClient/Program.cs:line 20

MacOS 10.12.6
Dotnet Core 2.0

[richardszalay]

Oddly I still can't reproduce the problem. I'm on Windows, but it works against both .NET and .NET Core.

Am I correct in assuming you're using MockHttp 1.5.0? It sounds like something that would have been a problem before 1.3.1

[chengbo]

Thanks for pointing out this, I've just checked my .csproj file, there was

<PackageReference Include="RichardSzalay.MockHttp" Version="3.0.0" />

in there.

Then I used below command to force install 1.5.0, everything works fine.

dotnet add package RichardSzalay.MockHttp --version 1.5.0

I don't know why 3.0.0 is installed without version parameter.

[richardszalay]

That's very strange. 3.0.0 was published in error in place of 1.3.0 but was unlisted so it shouldn't have been accepted unless explicitly requested.

[chengbo]

Yes, and it would be great if you could add a note for this in README file to prevent others from installing a wrong version without specifying version parameter.

[richardszalay]

Done, and I've also logged a bug with the dotnet cli team: https://github.com/dotnet/cli/issues/7492

[hecsalazar]

Hi Richard,

I confirm I have version 1.5.0, my code is a bit different, since I do an explicit dispose on the HttpResponseMessage after extracting the content:

public async Task HttpSendAsync(HttpRequestMessage requestMessage, X509Certificate2 sslCertificate = null)
{
var httpClient = GetHttpClient(sslCertificate);

        return await CallWithCircuitBreakerAsync(requestMessage.RequestUri.AbsoluteUri, async () =>
        {

            HttpResponseMessage httpResponse = null;
            try
            {
                httpResponse = await httpClient.SendAsync(requestMessage);
                var responseContent = await GetContentAsync(httpResponse);

                return responseContent;
            }
            catch (Exception e)
            {
                logger.Warn($"httpClient.HttpSendAsync failed. Method: {requestMessage.Method} Url: {requestMessage.RequestUri.AbsoluteUri} Error: {e.Message}",e);
                throw;
            }
            finally
            {
                // Dispose response object to avoid memory leak
                httpResponse?.Dispose();
            }

        });

    }

[richardszalay]

I can now reproduce the issue, and I'll look at patching it. FYI there's no need to dispose the response unless you are keeping a reference to it somewhere.

var handler = new MockHttpMessageHandler();

handler.When("*").Respond(HttpStatusCode.OK);

var client = handler.ToHttpClient();

var responseA = client.GetAsync("https://localhost/").GetAwaiter().GetResult();
responseA.Dispose();

var responseB = client.GetAsync("https://localhost/").GetAwaiter().GetResult();

[richardszalay]

This is fixed in 1.5.1 (just released)