Dependency exception when not using Subscriptions

With version 9.1.0-preview.35 the application that is not using subscriptions will see a dependency exception that reads like the following

Unable to resolve service for type ‘HotChocolate.AspNetCore.Subscriptions.IMessagePipeline’ while attempting to activate ‘HotChocolate.AspNetCore.Subscriptions.SubscriptionMiddleware’.

This is because ApplicationBuilderExtensions.UseGraphQL always registers SubscriptionMiddleware but it’s dependencies aren’t registered unless SubscriptionServiceCollectionExtensions.AddGraphQLSubscriptions is also called.

[michaelstaib]

It is quite easy to do that … I can borrow you some code for that. We will I think have this feature also in with V12. But I can give you some snippets for a basic rest middleware and the it is very easy to stitch rest in or OData. Can you join our slack channel? The invitation link is on our readme… the we can discuss things further.

[michaelstaib]

hi @okosodovictor,

this is a bug that we introduced in version 10. The stitching layer is basically missing the message pipeline. You can either add it.

services.AddGraphQLSubscriptions();

or you choose to remove the subscription middleware by specifying which transport middleware you want to use:

app
    .UseGraphQLHttpPost()
    .UseGraphQLHttpGet()
    .UseGraphQLHttpGetSchema();

regarding the UseGraphQLHttpGetSchema() middleware. This is kind of optional and also this particular middleware has an issue with .NET Core 3. We are currently working on a fix for 10.3.0.