Further consolidate the libraries

proxy/router/grpc/options.go

@@ -0,0 +1,32 @@
+package grpc
+
+import (
+	"github.com/micro/go-micro"
+	"github.com/micro/go-micro/server"
+)
+
+// WithBackend provides an option to set the proxy backend url
+func WithBackend(url string) micro.Option {
+	return func(o *micro.Options) {
+		// get the router
+		r := o.Server.Options().Router
+
+		// not set
+		if r == nil {
+			r = DefaultRouter
+			o.Server.Init(server.WithRouter(r))
+		}
+
+		// check its a proxy router
+		if proxyRouter, ok := r.(*Router); ok {
+			proxyRouter.Backend = url
+		}
+	}
+}
+
+// WithRouter provides an option to set the proxy router
+func WithRouter(r server.Router) micro.Option {
+	return func(o *micro.Options) {
+		o.Server.Init(server.WithRouter(r))
+	}
+}