Add grpc client and example

client/rpc_client.go

@@ -14,6 +14,8 @@ import (
 	rpc "github.com/youtube/vitess/go/rpcplus"
 	js "github.com/youtube/vitess/go/rpcplus/jsonrpc"
 	pb "github.com/youtube/vitess/go/rpcplus/pbrpc"
+	ctx "golang.org/x/net/context"
+	"google.golang.org/grpc"
 )
 
 type headerRoundTripper struct {
@@ -32,6 +34,18 @@ func (t *headerRoundTripper) RoundTrip(r *http.Request) (*http.Response, error)
 }
 
 func (r *RpcClient) call(address, path string, request Request, response interface{}) error {
+	switch request.ContentType() {
+	case "application/grpc":
+		cc, err := grpc.Dial(address)
+		if err != nil {
+			return errors.InternalServerError("go.micro.client", fmt.Sprintf("Error connecting to server: %v", err))
+		}
+		if err := grpc.Invoke(ctx.Background(), path, request.Request(), response, cc); err != nil {
+			return errors.InternalServerError("go.micro.client", fmt.Sprintf("Error sending request: %v", err))
+		}
+		return nil
+	}
+
 	pReq := &rpc.Request{
 		ServiceMethod: request.Method(),
 	}

examples/grpc_client.go

@@ -0,0 +1,23 @@
+package main
+
+import (
+	"fmt"
+
+	h "github.com/grpc/grpc-common/go/helloworld"
+	"github.com/myodc/go-micro/client"
+)
+
+// run github.com/grpc/grpc-common/go/greeter_server/main.go
+func main() {
+	req := client.NewRpcRequest("helloworld.Greeter", "SayHello", &h.HelloRequest{
+		Name: "John",
+	}, "application/grpc")
+
+	rsp := &h.HelloReply{}
+	err := client.CallRemote("localhost:50051", "helloworld.Greeter/SayHello", req, rsp)
+	if err != nil {
+		fmt.Println(err)
+	}
+
+	fmt.Println(rsp.Message)
+}