$Metadata with WebAPi OData Attribute Routing Not Working

Question

I'm using OData Attribute Routing for an OData endpoint. Here is an example of what I have:

[ODataRoutePrefix("Profile")]
public class ProfileODataController : ODataController
{
    [ODataRoute]
    [EnableQuery]
    public IHttpActionResult Get()
    {
        var repo = new Repositories.ProfileRepository();

        return Ok(repo.GetProfiles());
    }

    [ODataRoute("({key})")]
    [EnableQuery]
    public IHttpActionResult Get([FromODataUri] string key)
    {
        var repo = new Repositories.ProfileRepository();

        var result = repo.GetProfiles().SingleOrDefault(x => x.Id== key);
        if (result == null) return NotFound();

        return Ok(result);
    }
}

Here is my set up:

config.MapODataServiceRoute("odata", "odata", ModelGenerator.GetEdmModel());

Here is my EdmModel Generation:

public static IEdmModel GenerateEdmModel()
{
    var builder = new ODataConventionModelBuilder();

    builder.EntitySet<Profile>("Profile").EntityType.HasKey(x => x.Id);

    return builder.GetEdmModel();
}

The urls /odata/Profile and /odata/Profile('someid') both work, but when I try to access the $metadata endpoint (/odata/$metadata#Profile), I get the following error:

{"Message":"No HTTP resource was found that matches the request URI 'http://****/odata/$metadata'.","MessageDetail":"No type was found that matches the controller named 'Metadata'."}

Do I need to create a controller/action for serving the metadata? If so, how is that action implemented?

Nothing special found in your code. There is no need for additional action to serve metadata. You should be able to view metadata using .../odata/?$metadata and .../odata/$metadata. — Blaise
@Blaise As I expect as well, but it's not. I get the same error using either url. — Nathan A

Nathan A Nathan A · Accepted Answer · 2014-09-17T15:36:06

Turns out it had to do with my replacement of the IAssembliesResolver.

I had implemented a custom version to provide only the component assemblies that I had implemented controllers in. However, as the error said, it couldn't find a controller named MetadataController. Turns out, OData implements one: System.Web.OData.MetadataController, which provides for the $metadata keyword.

Since I had implemented my own IAssembliesResolver, the System.Web.OData assembly wasn't being included, and $metadata failed. Once I discovered this, and updated my assembly resolver to explicitly include the OData assembly, it now works as it should.

$Metadata with WebAPi OData Attribute Routing Not Working

1 Answers