Asp.net: 'application/grpc-web' is not supported

Question

I had Asp.net core and gRPC working on the browser...but now I get:

info: Grpc.AspNetCore.Server.ServerCallHandler[2]
  Request content-type of 'application/grpc-web' is not supported.

Any ideas on how to track this down?

user_10177987 · Answer

Likely an issue in your Startup.cs

My guess is that you are missing app.UseGrpcWeb() or the EnabledGrpc() on the EndpointConventionBuilder

user_1939630 · Answer

I ran across this issue. I had my app.UseGrpcWeb(); before app.UseRouting();

It had to be after.

So correct order is:

    app.UseRouting();
    app.UseGrpcWeb();