How to get project endpoint addresses to configure other projects

[Paulo Morgado (paulomorgado)]

In my Aspire playground I have a very simple identity provider that is used by the other projects.

ASP.NET Core 8.0 JWT bearer infrastructure does not use service discovery and I don't want to force it into the projects, so I'm setting it in Aspire:

var idp = builder.AddProject<Projects.Identitty>("Identity")
    .WithLaunchProfile("aspire")
    ;

var webService = builder.AddProject<Projects.WebService>("WebService")
    .WithLaunchProfile("aspire")
    .WithEnvironment("Security__Authentication__JwtBearerOptions__Authority", $"http://localhost:5501")
    .WithEnvironment("Security__Authentication__JwtBearerOptions__MetadataAddress", $"http://localhost:5501/.well-known/openid-configuration")
    ;

How can I get the endpoint for idp to set in webService?

[Paulo Morgado (paulomorgado)]

David Fowler (@davidfowl) answer on another question hints on a solution for the simple case of Security__Authentication__JwtBearerOptions__Authority, but doesn't solve for Security__Authentication__JwtBearerOptions__MetadataAddress-

[David Fowler (davidfowl)]

idp.GetEndpoint("http") ?

https://github.com/dotnet/eShop/blob/63e82c9e75b1a50cd28499240fcbc2942bdc6939/src/eShop.AppHost/Program.cs#L62

[Paulo Morgado (paulomorgado)]

It doesn't work if I have to compose it, like in the example above.

[Paulo Morgado (paulomorgado)]

How can I use service discovery on a project where I know I have components that are not yet ready for that?

[Damian Edwards (DamianEdwards)]

Service Discovery should work for any component where the HttpClient is exposed. If the HttpClient is internal to the component, then you'd need to manually resolve the address using the Service Discovery APIs at application startup and then configure the component to use the resolved address, but of course then you won't get any on-demand features of Service Discovery (e.g. client-side load balancing, etc.).

[Paulo Morgado (paulomorgado)]

That's the case of authentication and authorization.

For now, I would be happy with just getting the first address from service discovery to override the values in configuration.

Are there any docs or samples on how to do that?

[Paulo Morgado (paulomorgado)]

For JwtBearer I'm doing this:

services
    .AddAuthentication()
    .AddJwtBearer();

services.ConfigureOptions<JwtBearerPostConfigureOptions>();

// ...

private sealed class JwtBearerPostConfigureOptions : IPostConfigureOptions<JwtBearerOptions>
{
    private readonly IHttpClientFactory _httpClientFactory;

    public JwtBearerPostConfigureOptions(IHttpClientFactory httpClientFactory)
    {
        _httpClientFactory = httpClientFactory;
    }
    public void PostConfigure(string? name, JwtBearerOptions options)
    {
        options.Backchannel = string.IsNullOrEmpty(name) ? _httpClientFactory.CreateClient() : _httpClientFactory.CreateClient(name);
    }
}

This way, JwtBearer not only can use service discovery, but can also use resilience.