Identity Server 4 error "keyset is missing"

Question

After I config EntityFramework the code not working, I just did like the doc int this page identity server 4 official doc

Just like the doc say at the last of page "You should now be able to run any of the existing client applications and sign-in, get tokens, and call the API – all based upon the database configuration.". But when I run the console application i see the following error ,no matter that the server info looks OK, this is the discovery document.I'm sure that I start the Server before Client. I can't find out reason or something related on the google and Stack Overflow. I want to know what is the meaning of "key set missing", and how to fix it.

Answer 1

Did you add the following?

public void ConfigureServices(IServiceCollection services)
{
    services.AddIdentityServer()
            .AddDeveloperSigningCredential()....
}

I got the following Error when this is not added.

System.InvalidOperationException: Policy error while contacting the discovery endpoint http://localhost:5050/.well-known/openid-configuration: Keyset is missing
       at IdentityModel.AspNetCore.OAuth2Introspection.PostConfigureOAuth2IntrospectionOptions.<GetIntrospectionEndpointFromDiscoveryDocument>d__3.MoveNext() 

Very annoying that this is never documented.

P.S. you have to restart your Client before testing it. The client call's the discovery only once.