Set Rate limiter schema for Routes

[Kahbazi]

What should we add or change to make your life better?

The new RateLimiter middleware per endpoint is currently in draft and it is worth being able to set different policy for YARP routes for it when it's merged.

public sealed record RouteConfig
{
+     public string? RateLimiterPolicy { get; init; }
}

  "ReverseProxy": {
    "Routes": {
      "route1" : {
        "ClusterId": "cluster1",
+      "RateLimiterPolicy": "customPolicy",
        "Match": {
          "Hosts": [ "localhost" ]
        },
      }
    },
    "Clusters": {
      "cluster1": {
        "Destinations": {
          "cluster1/destination1": {
            "Address": "https://localhost:10001/"
          }
        }
      }
    }
  }
}

Why is this important to you?

[Tratcher]

Also tracked by dotnet/aspnetcore#37387

[karelz]

Triage: We need to light up .NET 7.0 feature like this one.

[Tratcher]

Unblocked by https://github.com/dotnet/aspnetcore/blob/a633e8821026868f180be736112f35e6f63159e8/src/Middleware/RateLimiting/src/EnableRateLimitingAttribute.cs.

We'll need to update the runtime/sdk in global.json to consume this.

[Tratcher]

@Kahbazi want to try this now? It should be almost a copy of the auth feature.

[Kahbazi]

@Tratcher Yes I will take this one.

[Kahbazi]

Ok! I started to implement this and I hit some design issues. RateLimitingMiddleware is not in the ASP.Net Core framework. It has its own nuget package. What is the approach here?

1. Add reference to Microsoft.AspNetCore.RateLimiting in YARP. This is an easy but maybe not so good solution.
2. Create a new package Microsoft.ReverseProxy.RateLimiting. This would have reference to the middleware but then extending RouteInfo (Design: Richer Extensibility for routes and clusters #1796) might be challenging.

[Tratcher]

It should be in the framework for rc1. You'll need a current runtime/SDK dependency to try that.
dotnet/aspnetcore@9d4537c

[mburumaxwell]

Are contributions still being accepted for this or has it already been implemented?

[Tratcher]

@mburumaxwell It's still available, go ahead.