Problem with AppDbContext derived from IdentityDbContext

[milosloub]

Hello,
after update from 2.1.11 to 2.2, there si error in Startup.cs inicialization:
services.AddJsonApi<AppDbContext>

Type does not implement 'IIdentifiable'\r\nParameter name: resourceType

Stack trace:

at JsonApiDotNetCore.Builders.ContextGraphBuilder.GetIdType(Type resourceType)
at JsonApiDotNetCore.Builders.ContextGraphBuilder.AddDbContextT
at JsonApiDotNetCore.Extensions.IServiceCollectionExtensions.<>c__21.<AddJsonApi>b__2_0(IContextGraphBuilder builder) at JsonApiDotNetCore.Configuration.JsonApiOptions.BuildContextGraph(Action1 builder)
at JsonApiDotNetCore.Extensions.IServiceCollectionExtensions.AddJsonApi[TContext](IServiceCollection services, Action`1 options, IMvcBuilder mvcBuilder)

If AppDbContext derived from DbContext, everything is ok, but my AppDbContext derived from IdentityDbContext<User,Role,int>.

Can you make some investigation? Thank you.

[jaredcnance]

So, this is the problem area:

JsonApiDotNetCore/src/JsonApiDotNetCore/Builders/ContextGraphBuilder.cs

Lines 136 to 146 in e30f911

	private Type GetIdType(Type resourceType)
	{
	var interfaces = resourceType.GetInterfaces();
	foreach (var type in interfaces)
	{
	if (type.GetTypeInfo().IsGenericType && type.GetGenericTypeDefinition() == typeof(IIdentifiable<>))
	return type.GetGenericArguments()[0];
	}
	throw new ArgumentException("Type does not implement 'IIdentifiable<TId>'", nameof(resourceType));
	}

I'm not sure right now why this was ever working. The correct behavior would be to log a warning rather than throw the exception. The reason it fails with the IdentityDbContext is because the Identity models do not implement IIdentifiable which should be handled. And we shouldn't require all models on a context to be JsonAPI resources. Depending on the size of your context you could temporarily manually construct the context graph:

services.AddJsonApi(options => {
        options.BuildContextGraph((builder) => {
            builder.AddResource<MyModel>("my-models");
        });
    }, mvcBuilder);

https://json-api-dotnet.github.io/#/context-graph

I will work on having a fix in v2.2.1 as soon as possible.

[milosloub]

For me this temporary solution is ok until it is fixed.
Btw thank you for this library. It's total masterpiece

[jaredcnance]

@milosloub please upgrade to 2.2.1 and let me know if that solves your problem.

[milosloub]

@jaredcnance Wow, that was fast. After upgrade it works perfectly. Thank you