IHttpContextAccessor.HttpContext returns null when executing within an odata batch call.

[UmairB]

IHttpContextAccessor.HttpContext returns null when executing within an odata batch call.

Assemblies affected

Microsoft.AspNetCore.OData 7.5.0

Reproduce steps

Simply setup a simple odata batch pipeline

var defaultBatchHandler = new DefaultODataBatchHandler();
defaultBatchHandler.MessageQuotas.MaxNestingDepth = 2;
defaultBatchHandler.MessageQuotas.MaxOperationsPerChangeset = 10;

and create an action that uses the http context accessor:

[ODataRoutePrefix("me")]
public class MeController : ODataController
{
    private readonly IHttpContextAccessor httpContextAccessor;

    public MeController(IHttpContextAccessor httpContextAccessor)
    {
        this.httpContextAccessor = httpContextAccessor;
    }

    [EnableQuery]
    [HttpGet]
    public User Get()
    { 
        var user = this.httpContextAccessor.HttpContext.User;
        // this.HttpContext is fine
        return new User { Name = user.Identity.Name };
    }
}

the following request

POST /$batch
Content-Type: application/json
{
    "requests": [
        {
            "id": "1",
            "method": "GET",
            "url": "/me"
        }
    ]
}

Produces the error

Expected result

In the example above HttpContextAccessor.HttpContext should be equal to this.HttpContext - the http context of the controller/action.

Actual result

HttpContextAccessor.HttpContext is null.

Additional detail

I realize from the simple example above I can simply use this.HttpContext but I need to access the httpcontext in a more deeper part of my code.

[newclaus]

The same issue is reproduced on 7.4.1

[xuzhg]

do we need to add the new httpContext for the sub request at https://github.com/OData/WebApi/blob/master/src/Microsoft.AspNetCore.OData/Batch/ODataBatchReaderExtensions.cs#L251 into the IHttpContextAccessor?

[UmairB]

do we need to add the new httpContext for the sub request at https://github.com/OData/WebApi/blob/master/src/Microsoft.AspNetCore.OData/Batch/ODataBatchReaderExtensions.cs#L251 into the IHttpContextAccessor?

Under which circumstances is IHttpContextFactory not available? Even if IHttpContextFactory was available (which sets the context on default implementation of IHttpContextAccessor as far as I remember), the same problem would occur due to AsyncLocal usage in the context accessor... (we are already deep in an async method chain)

?

[ThomasWendrock]

We have faced the same issue and working with a workaround like this:

[ODataRoutePrefix("me")]
    public class MeController : ODataController
    {
        private readonly ClaimsPrincipal user;

        public MeController(IHttpContextAccessor httpContextAccessor, IActionContextAccessor actionContextAccessor)
        {
            var httpContext = httpContextAccessor.HttpContext;
            if (httpContext == null)
            {
                // this occurs since .NET 3.1, when a batch request is running
                httpContext = actionContextAccessor.ActionContext?.HttpContext;
            }
            this.user = httpContext?.User;
        }
        [EnableQuery]
        [HttpGet]
        public User Get()
        {
            return new User { Name = user.Identity.Name };
        }
    }

See also this thread on stackoverflow.

The ActionContextAccessor needn't to be put to DI manually. Maybe this works for you too.

[NicholasNoise]

@ThomasWendrock
Your tip is quite useful to provide context for changesets, but does not cover every case, f.e. batch post-processing.
I've investigated deep down and found out the reason:
https://github.com/dotnet/aspnetcore/blob/master/src/Hosting/Hosting/src/Http/DefaultHttpContextFactory.cs#L73
We should not ever use factory for sub-requests.

[GuillaumeBONHOMMEAU]

Hi, any news on that subject ? :)
We faced that issue too and used a similar workaround like Thomas mentionned.
Still, it would be awesome to have this fix :)

[NicholasNoise]

I've made a fix long ago, but it still has not been merged or no comments on how to rework it.