From 0da8256426e865ebd4e31088ebcb535c18b47ece Mon Sep 17 00:00:00 2001
From: Asim Aslam <asim@aslam.me>
Date: Wed, 26 Jun 2019 20:51:13 +0100
Subject: [PATCH] Accept a range of addresses

---
 client/grpc/grpc.go  |  4 ++--
 client/options.go    |  8 ++++----
 client/rpc_client.go | 29 ++++++++++++++++++-----------
 3 files changed, 24 insertions(+), 17 deletions(-)

diff --git a/client/grpc/grpc.go b/client/grpc/grpc.go
index 3430fbfc..df4163c7 100644
--- a/client/grpc/grpc.go
+++ b/client/grpc/grpc.go
@@ -59,14 +59,14 @@ func (g *grpcClient) next(request client.Request, opts client.CallOptions) (sele
 
 	// get proxy address
 	if prx := os.Getenv("MICRO_PROXY_ADDRESS"); len(prx) > 0 {
-		opts.Address = prx
+		opts.Address = []string{prx}
 	}
 
 	// return remote address
 	if len(opts.Address) > 0 {
 		return func() (*registry.Node, error) {
 			return &registry.Node{
-				Address: opts.Address,
+				Address: opts.Address[0],
 			}, nil
 		}, nil
 	}
diff --git a/client/options.go b/client/options.go
index 5a0f4100..9f363d74 100644
--- a/client/options.go
+++ b/client/options.go
@@ -43,8 +43,8 @@ type Options struct {
 type CallOptions struct {
 	SelectOptions []selector.SelectOption
 
-	// Address of remote host
-	Address string
+	// Address of remote hosts
+	Address []string
 	// Backoff func
 	Backoff BackoffFunc
 	// Check if retriable func
@@ -245,8 +245,8 @@ func WithExchange(e string) PublishOption {
 	}
 }
 
-// WithAddress sets the remote address to use rather than using service discovery
-func WithAddress(a string) CallOption {
+// WithAddress sets the remote addresses to use rather than using service discovery
+func WithAddress(a ...string) CallOption {
 	return func(o *CallOptions) {
 		o.Address = a
 	}
diff --git a/client/rpc_client.go b/client/rpc_client.go
index 36b3dcf7..c724435a 100644
--- a/client/rpc_client.go
+++ b/client/rpc_client.go
@@ -283,29 +283,36 @@ func (r *rpcClient) next(request Request, opts CallOptions) (selector.Next, erro
 
 	// get proxy address
 	if prx := os.Getenv("MICRO_PROXY_ADDRESS"); len(prx) > 0 {
-		opts.Address = prx
+		opts.Address = []string{prx}
 	}
 
 	// return remote address
 	if len(opts.Address) > 0 {
-		address := opts.Address
-		port := 0
+		var nodes []*registry.Node
 
-		host, sport, err := net.SplitHostPort(opts.Address)
-		if err == nil {
-			address = host
-			port, _ = strconv.Atoi(sport)
-		}
+		for _, addr := range opts.Address {
+			address := addr
+			port := 0
 
-		return func() (*registry.Node, error) {
-			return &registry.Node{
+			host, sport, err := net.SplitHostPort(addr)
+			if err == nil {
+				address = host
+				port, _ = strconv.Atoi(sport)
+			}
+
+			nodes = append(nodes, &registry.Node{
 				Address: address,
 				Port:    port,
 				// Set the protocol
 				Metadata: map[string]string{
 					"protocol": "mucp",
 				},
-			}, nil
+			})
+		}
+
+		// crude return method
+		return func() (*registry.Node, error) {
+			return nodes[time.Now().Unix()%int64(len(nodes))], nil
 		}, nil
 	}