From 8245390b5a4872330a98d1ce5e3681dfb8dd9a18 Mon Sep 17 00:00:00 2001
From: Asim <asim@chuhnk.me>
Date: Thu, 26 May 2016 18:01:02 +0100
Subject: [PATCH] Support endpoint metadata

---
 server/handler.go     |  9 +++++++++
 server/rpc_handler.go | 10 +++++++++-
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/server/handler.go b/server/handler.go
index b944efeb..d3a25d86 100644
--- a/server/handler.go
+++ b/server/handler.go
@@ -34,6 +34,7 @@ type Subscriber interface {
 
 type HandlerOptions struct {
 	Internal bool
+	Metadata map[string]map[string]string
 }
 
 type SubscriberOptions struct {
@@ -50,6 +51,14 @@ func InternalHandler(b bool) HandlerOption {
 	}
 }
 
+// EndpointMetadata is a Handler option that allows metadata to be added to
+// individual endpoints.
+func EndpointMetadata(endpoint string, metadata map[string]string) HandlerOption {
+	return func(o *HandlerOptions) {
+		o.Metadata[endpoint] = metadata
+	}
+}
+
 // Internal Subscriber options specifies that a subscriber is not advertised
 // to the discovery system.
 func InternalSubscriber(b bool) SubscriberOption {
diff --git a/server/rpc_handler.go b/server/rpc_handler.go
index e01b4b25..42ec7f0f 100644
--- a/server/rpc_handler.go
+++ b/server/rpc_handler.go
@@ -14,7 +14,10 @@ type rpcHandler struct {
 }
 
 func newRpcHandler(handler interface{}, opts ...HandlerOption) Handler {
-	var options HandlerOptions
+	options := HandlerOptions{
+		Metadata: make(map[string]map[string]string),
+	}
+
 	for _, o := range opts {
 		o(&options)
 	}
@@ -28,6 +31,11 @@ func newRpcHandler(handler interface{}, opts ...HandlerOption) Handler {
 	for m := 0; m < typ.NumMethod(); m++ {
 		if e := extractEndpoint(typ.Method(m)); e != nil {
 			e.Name = name + "." + e.Name
+
+			for k, v := range options.Metadata[e.Name] {
+				e.Metadata[k] = v
+			}
+
 			endpoints = append(endpoints, e)
 		}
 	}