Server.cs

Server.cs

using System;
using System.Threading.Tasks;
using Grpc.Core;

using Coprocess;

class DispatcherImpl : Dispatcher.DispatcherBase
{
    public DispatcherImpl()
    {
        Console.WriteLine("Instantiating DispatcherImpl");
    }


    // The Dispatch method will be called by Tyk for every configured hook, we'll implement a very simple dispatcher here:
    public override Task<Coprocess.Object> Dispatch(Coprocess.Object thisObject, ServerCallContext context)
    {
        // thisObject is the request object:
        Console.WriteLine("Receiving object: " + thisObject.ToString());

        // hook contains the hook name, this will be defined in our plugin bundle and the implementation will be a method in this class (DispatcherImpl), we'll look it up:
        var hook = this.GetType().GetMethod(thisObject.HookName);

        // If hook is null then a handler method for this hook isn't implemented, we'll log this anyway:
        if (hook == null)
        {
            Console.WriteLine("Hook name: " + thisObject.HookName + " (not implemented!)");
            // We return the unmodified request object, so that Tyk can proxy this in the normal way.
            return Task.FromResult(thisObject);
        };

        // If there's a handler method, let's log it and proceed with our dispatch work:
        Console.WriteLine("Hook name: " + thisObject.HookName + " (implemented)");

        // This will dynamically invoke our hook method, and cast the returned object to the required Protocol Buffers data structure:
        var output = hook.Invoke(this, new object[] { thisObject, context });
        return (Task<Coprocess.Object>)output;
    }

    // MyPreMiddleware implements a PRE hook, it will be called before the request is proxied upstream and before the authentication step:
    public Task<Coprocess.Object> MyPreMiddleware(Coprocess.Object thisObject, ServerCallContext context)
    {
        Console.WriteLine("Calling MyPreMiddleware.");
        // We'll inject a header in this request:
        thisObject.Request.SetHeaders["my-header"] = "my-value";
        return Task.FromResult(thisObject);
    }

    // MyAuthCheck implements a custom authentication mechanism, it will initialize a session object if the token matches a certain value:
    public Task<Coprocess.Object> MyAuthCheck(Coprocess.Object thisObject, ServerCallContext context)
    {
        // Request.Headers contains all the request headers, we retrieve the authorization token:
        var token = thisObject.Request.Headers["Authorization"];
        Console.WriteLine("Calling MyAuthCheck with token = " + token);

        // We initialize a session object if the token matches "abc123":
        if (token == "abc123")
        {
            Console.WriteLine("Successful auth!");
            var session = new Coprocess.SessionState();
            session.Rate = 1000;
            session.Per = 10;
            session.QuotaMax = 60;
            session.QuotaRenews = 1479033599;
            session.QuotaRemaining = 0;
            session.QuotaRenewalRate = 120;
            session.Expires = 1479033599;

            session.LastUpdated = 1478033599.ToString();

            thisObject.Metadata["token"] = token;
            thisObject.Session = session;
            return Task.FromResult(thisObject);

        }

        // If the token isn't "abc123", we return the request object in the original state, without a session object, Tyk will reject this request:
        Console.WriteLine("Rejecting auth!");
        return Task.FromResult(thisObject);
    }
}