Merge pull request #375 from micro/codec

further codec changes

client/rpc_client.go

@@ -97,7 +97,7 @@ func (r *rpcClient) call(ctx context.Context, address string, req Request, resp
 		request: req,
 		closed:  make(chan bool),
 		codec:   newRpcCodec(msg, c, cf),
-		seq:     seq,
+		seq:     fmt.Sprintf("%v", seq),
 	}
 	defer stream.Close()
 

client/rpc_codec.go

@@ -4,7 +4,6 @@ import (
 	"bytes"
 	errs "errors"
 	"fmt"
-	"strconv"
 
 	"github.com/micro/go-micro/codec"
 	raw "github.com/micro/go-micro/codec/bytes"
@@ -55,13 +54,13 @@ type clientCodec interface {
 type request struct {
 	Service       string
 	ServiceMethod string   // format: "Service.Method"
-	Seq           uint64   // sequence number chosen by client
+	Seq           string   // sequence number chosen by client
 	next          *request // for free list in Server
 }
 
 type response struct {
 	ServiceMethod string    // echoes that of the Request
-	Seq           uint64    // echoes that of the request
+	Seq           string    // echoes that of the request
 	Error         string    // error, if any.
 	next          *response // for free list in Server
 }
@@ -115,7 +114,7 @@ func (c *rpcCodec) Write(req *request, body interface{}) error {
 		Method: req.ServiceMethod,
 		Type:   codec.Request,
 		Header: map[string]string{
-			"X-Micro-Id":      fmt.Sprintf("%d", req.Seq),
+			"X-Micro-Id":      fmt.Sprintf("%v", req.Seq),
 			"X-Micro-Service": req.Service,
 			"X-Micro-Method":  req.ServiceMethod,
 		},
@@ -161,9 +160,8 @@ func (c *rpcCodec) Read(r *response, b interface{}) error {
 		r.ServiceMethod = me.Header["X-Micro-Method"]
 	}
 
-	if me.Id == 0 && len(me.Header["X-Micro-Id"]) > 0 {
+	if len(me.Id) == 0 {
-		id, _ := strconv.ParseInt(me.Header["X-Micro-Id"], 10, 64)
+		r.Seq = me.Header["X-Micro-Id"]
-		r.Seq = uint64(id)
 	}
 
 	if err != nil {

client/rpc_stream.go

@@ -9,7 +9,7 @@ import (
 // Implements the streamer interface
 type rpcStream struct {
 	sync.RWMutex
-	seq     uint64
+	seq     string
 	closed  chan bool
 	err     error
 	request Request

codec/codec.go

@@ -34,7 +34,7 @@ type Codec interface {
 // the communication, likely followed by the body.
 // In the case of an error, body may be nil.
 type Message struct {
-	Id     uint64
+	Id     string
 	Type   MessageType
 	Target string
 	Method string

codec/jsonrpc/client.go

@@ -19,17 +19,17 @@ type clientCodec struct {
 	resp clientResponse
 
 	sync.Mutex
-	pending map[uint64]string
+	pending map[interface{}]string
 }
 
 type clientRequest struct {
 	Method string         `json:"method"`
 	Params [1]interface{} `json:"params"`
-	ID     uint64         `json:"id"`
+	ID     interface{}    `json:"id"`
 }
 
 type clientResponse struct {
-	ID     uint64           `json:"id"`
+	ID     interface{}      `json:"id"`
 	Result *json.RawMessage `json:"result"`
 	Error  interface{}      `json:"error"`
 }
@@ -39,7 +39,7 @@ func newClientCodec(conn io.ReadWriteCloser) *clientCodec {
 		dec:     json.NewDecoder(conn),
 		enc:     json.NewEncoder(conn),
 		c:       conn,
-		pending: make(map[uint64]string),
+		pending: make(map[interface{}]string),
 	}
 }
 
@@ -71,7 +71,7 @@ func (c *clientCodec) ReadHeader(m *codec.Message) error {
 	c.Unlock()
 
 	m.Error = ""
-	m.Id = c.resp.ID
+	m.Id = fmt.Sprintf("%v", c.resp.ID)
 	if c.resp.Error != nil {
 		x, ok := c.resp.Error.(string)
 		if !ok {

codec/jsonrpc/server.go

@@ -2,9 +2,8 @@ package jsonrpc
 
 import (
 	"encoding/json"
-	"errors"
+	"fmt"
 	"io"
-	"sync"
 
 	"github.com/micro/go-micro/codec"
 )
@@ -17,20 +16,16 @@ type serverCodec struct {
 	// temporary work space
 	req  serverRequest
 	resp serverResponse
-
-	sync.Mutex
-	seq     uint64
-	pending map[uint64]*json.RawMessage
 }
 
 type serverRequest struct {
 	Method string           `json:"method"`
 	Params *json.RawMessage `json:"params"`
-	ID     *json.RawMessage `json:"id"`
+	ID     interface{}      `json:"id"`
 }
 
 type serverResponse struct {
-	ID     *json.RawMessage `json:"id"`
+	ID     interface{} `json:"id"`
 	Result interface{} `json:"result"`
 	Error  interface{} `json:"error"`
 }
@@ -40,7 +35,6 @@ func newServerCodec(conn io.ReadWriteCloser) *serverCodec {
 		dec: json.NewDecoder(conn),
 		enc: json.NewEncoder(conn),
 		c:   conn,
-		pending: make(map[uint64]*json.RawMessage),
 	}
 }
 
@@ -50,7 +44,7 @@ func (r *serverRequest) reset() {
 		*r.Params = (*r.Params)[0:0]
 	}
 	if r.ID != nil {
-		*r.ID = (*r.ID)[0:0]
+		r.ID = nil
 	}
 }
 
@@ -60,14 +54,8 @@ func (c *serverCodec) ReadHeader(m *codec.Message) error {
 		return err
 	}
 	m.Method = c.req.Method
-
+	m.Id = fmt.Sprintf("%v", c.req.ID)
-	c.Lock()
-	c.seq++
-	c.pending[c.seq] = c.req.ID
 	c.req.ID = nil
-	m.Id = c.seq
-	c.Unlock()
-
 	return nil
 }
 
@@ -84,19 +72,7 @@ var null = json.RawMessage([]byte("null"))
 
 func (c *serverCodec) Write(m *codec.Message, x interface{}) error {
 	var resp serverResponse
-	c.Lock()
+	resp.ID = m.Id
-	b, ok := c.pending[m.Id]
-	if !ok {
-		c.Unlock()
-		return errors.New("invalid sequence number in response")
-	}
-	c.Unlock()
-
-	if b == nil {
-		// Invalid request so no id.  Use JSON null.
-		b = &null
-	}
-	resp.ID = b
 	resp.Result = x
 	if m.Error == "" {
 		resp.Error = nil

codec/proto/proto.go

@@ -22,11 +22,18 @@ func (c *Codec) ReadBody(b interface{}) error {
 	if err != nil {
 		return err
 	}
+	if b == nil {
+		return nil
+	}
 	return proto.Unmarshal(buf, b.(proto.Message))
 }
 
 func (c *Codec) Write(m *codec.Message, b interface{}) error {
-	buf, err := proto.Marshal(b.(proto.Message))
+	p, ok := b.(proto.Message)
+	if !ok {
+		return nil
+	}
+	buf, err := proto.Marshal(p)
 	if err != nil {
 		return err
 	}

codec/protorpc/protorpc.go

@@ -5,6 +5,7 @@ import (
 	"bytes"
 	"fmt"
 	"io"
+	"strconv"
 	"sync"
 
 	"github.com/golang/protobuf/proto"
@@ -31,13 +32,22 @@ func (c *protoCodec) String() string {
 	return "proto-rpc"
 }
 
+func id(id string) *uint64 {
+	p, err := strconv.ParseInt(id, 10, 64)
+	if err != nil {
+		p = 0
+	}
+	i := uint64(p)
+	return &i
+}
+
 func (c *protoCodec) Write(m *codec.Message, b interface{}) error {
 	switch m.Type {
 	case codec.Request:
 		c.Lock()
 		defer c.Unlock()
 		// This is protobuf, of course we copy it.
-		pbr := &Request{ServiceMethod: &m.Method, Seq: &m.Id}
+		pbr := &Request{ServiceMethod: &m.Method, Seq: id(m.Id)}
 		data, err := proto.Marshal(pbr)
 		if err != nil {
 			return err
@@ -63,7 +73,7 @@ func (c *protoCodec) Write(m *codec.Message, b interface{}) error {
 	case codec.Response:
 		c.Lock()
 		defer c.Unlock()
-		rtmp := &Response{ServiceMethod: &m.Method, Seq: &m.Id, Error: &m.Error}
+		rtmp := &Response{ServiceMethod: &m.Method, Seq: id(m.Id), Error: &m.Error}
 		data, err := proto.Marshal(rtmp)
 		if err != nil {
 			return err
@@ -117,7 +127,7 @@ func (c *protoCodec) ReadHeader(m *codec.Message, mt codec.MessageType) error {
 			return err
 		}
 		m.Method = rtmp.GetServiceMethod()
-		m.Id = rtmp.GetSeq()
+		m.Id = fmt.Sprintf("%d", rtmp.GetSeq())
 	case codec.Response:
 		data, err := ReadNetString(c.rwc)
 		if err != nil {
@@ -129,7 +139,7 @@ func (c *protoCodec) ReadHeader(m *codec.Message, mt codec.MessageType) error {
 			return err
 		}
 		m.Method = rtmp.GetServiceMethod()
-		m.Id = rtmp.GetSeq()
+		m.Id = fmt.Sprintf("%d", rtmp.GetSeq())
 		m.Error = rtmp.GetError()
 	case codec.Publication:
 		_, err := io.Copy(c.buf, c.rwc)

server/options.go

@@ -25,8 +25,12 @@ type Options struct {
 	HdlrWrappers []HandlerWrapper
 	SubWrappers  []SubscriberWrapper
 
+	// The register expiry time
 	RegisterTTL time.Duration
 
+	// The router for requests
+	Router Router
+
 	// Debug Handler which can be set by a user
 	DebugHandler debug.DebugHandler
 
@@ -164,6 +168,13 @@ func RegisterTTL(t time.Duration) Option {
 	}
 }
 
+// WithRouter sets the request router
+func WithRouter(r Router) Option {
+	return func(o *Options) {
+		o.Router = r
+	}
+}
+
 // Wait tells the server to wait for requests to finish before exiting
 func Wait(b bool) Option {
 	return func(o *Options) {

server/rpc_codec.go

@@ -2,8 +2,6 @@ package server
 
 import (
 	"bytes"
-	"fmt"
-	"strconv"
 
 	"github.com/micro/go-micro/codec"
 	raw "github.com/micro/go-micro/codec/bytes"
@@ -19,6 +17,7 @@ import (
 type rpcCodec struct {
 	socket transport.Socket
 	codec  codec.Codec
+	first  bool
 
 	req *transport.Message
 	buf *readWriteCloser
@@ -65,12 +64,13 @@ func (rwc *readWriteCloser) Close() error {
 	return nil
 }
 
-func newRpcCodec(req *transport.Message, socket transport.Socket, c codec.NewCodec) serverCodec {
+func newRpcCodec(req *transport.Message, socket transport.Socket, c codec.NewCodec) codec.Codec {
 	rwc := &readWriteCloser{
 		rbuf: bytes.NewBuffer(req.Body),
 		wbuf: bytes.NewBuffer(nil),
 	}
 	r := &rpcCodec{
+		first:  true,
 		buf:    rwc,
 		codec:  c(rwc),
 		req:    req,
@@ -79,36 +79,43 @@ func newRpcCodec(req *transport.Message, socket transport.Socket, c codec.NewCod
 	return r
 }
 
-func (c *rpcCodec) ReadHeader(r *request, first bool) error {
+func (c *rpcCodec) ReadHeader(r *codec.Message, t codec.MessageType) error {
 	m := codec.Message{Header: c.req.Header}
 
-	if !first {
+	// if its a follow on request read it
+	if !c.first {
 		var tm transport.Message
+
+		// read off the socket
 		if err := c.socket.Recv(&tm); err != nil {
 			return err
 		}
+		// reset the read buffer
 		c.buf.rbuf.Reset()
+
+		// write the body to the buffer
 		if _, err := c.buf.rbuf.Write(tm.Body); err != nil {
 			return err
 		}
 
+		// set the message header
 		m.Header = tm.Header
 	}
 
+	// no longer first read
+	c.first = false
+
 	// set some internal things
 	m.Target = m.Header["X-Micro-Service"]
 	m.Method = m.Header["X-Micro-Method"]
-
+	m.Id = m.Header["X-Micro-Id"]
-	// set id
-	if len(m.Header["X-Micro-Id"]) > 0 {
-		id, _ := strconv.ParseInt(m.Header["X-Micro-Id"], 10, 64)
-		m.Id = uint64(id)
-	}
 
 	// read header via codec
 	err := c.codec.ReadHeader(&m, codec.Request)
-	r.ServiceMethod = m.Method
+
-	r.Seq = m.Id
+	// set the method/id
+	r.Method = m.Method
+	r.Id = m.Id
 
 	return err
 }
@@ -117,21 +124,28 @@ func (c *rpcCodec) ReadBody(b interface{}) error {
 	return c.codec.ReadBody(b)
 }
 
-func (c *rpcCodec) Write(r *response, body interface{}, last bool) error {
+func (c *rpcCodec) Write(r *codec.Message, body interface{}) error {
 	c.buf.wbuf.Reset()
+
+	// create a new message
 	m := &codec.Message{
-		Method: r.ServiceMethod,
+		Method: r.Method,
-		Id:     r.Seq,
+		Id:     r.Id,
 		Error:  r.Error,
-		Type:   codec.Response,
+		Type:   r.Type,
 		Header: map[string]string{
-			"X-Micro-Id":     fmt.Sprintf("%d", r.Seq),
+			"X-Micro-Id":     r.Id,
-			"X-Micro-Method": r.ServiceMethod,
+			"X-Micro-Method": r.Method,
 			"X-Micro-Error":  r.Error,
+			"Content-Type":   c.req.Header["Content-Type"],
 		},
 	}
+
+	// write to the body
 	if err := c.codec.Write(m, body); err != nil {
 		c.buf.wbuf.Reset()
+
+		// write an error if it failed
 		m.Error = errors.Wrapf(err, "Unable to encode body").Error()
 		m.Header["X-Micro-Error"] = m.Error
 		if err := c.codec.Write(m, nil); err != nil {
@@ -139,7 +153,7 @@ func (c *rpcCodec) Write(r *response, body interface{}, last bool) error {
 		}
 	}
 
-	m.Header["Content-Type"] = c.req.Header["Content-Type"]
+	// send on the socket
 	return c.socket.Send(&transport.Message{
 		Header: m.Header,
 		Body:   c.buf.wbuf.Bytes(),
@@ -151,3 +165,7 @@ func (c *rpcCodec) Close() error {
 	c.codec.Close()
 	return c.socket.Close()
 }
+
+func (c *rpcCodec) String() string {
+	return "rpc"
+}

server/rpc_codec_test.go

@@ -47,12 +47,11 @@ func TestCodecWriteError(t *testing.T) {
 		socket: socket,
 	}
 
-	err := c.Write(&response{
+	err := c.Write(&codec.Message{
-		ServiceMethod: "Service.Method",
+		Method: "Service.Method",
-		Seq:           0,
+		Id:     "0",
 		Error:  "",
-		next:          nil,
+	}, "body")
-	}, "body", false)
 
 	if err != nil {
 		t.Fatalf(`Expected Write to fail; got "%+v" instead`, err)

server/rpc_router.go

@@ -17,6 +17,7 @@ import (
 	"unicode/utf8"
 
 	"github.com/micro/go-log"
+	"github.com/micro/go-micro/codec"
 )
 
 var (
@@ -48,15 +49,12 @@ type service struct {
 }
 
 type request struct {
-	ServiceMethod string   // format: "Service.Method"
+	msg  *codec.Message
-	Seq           uint64   // sequence number chosen by client
 	next *request // for free list in Server
 }
 
 type response struct {
-	ServiceMethod string    // echoes that of the Request
+	msg  *codec.Message
-	Seq           uint64    // echoes that of the request
-	Error         string    // error, if any.
 	next *response // for free list in Server
 }
 
@@ -215,30 +213,34 @@ func (router *router) Handle(h Handler) error {
 	return nil
 }
 
-func (router *router) sendResponse(sending sync.Locker, req *request, reply interface{}, codec serverCodec, errmsg string, last bool) (err error) {
+func (router *router) sendResponse(sending sync.Locker, req *request, reply interface{}, cc codec.Codec, errmsg string, last bool) (err error) {
+	msg := new(codec.Message)
+	msg.Type = codec.Response
 	resp := router.getResponse()
+	resp.msg = msg
+
 	// Encode the response header
-	resp.ServiceMethod = req.ServiceMethod
+	resp.msg.Method = req.msg.Method
 	if errmsg != "" {
-		resp.Error = errmsg
+		resp.msg.Error = errmsg
 		reply = invalidRequest
 	}
-	resp.Seq = req.Seq
+	resp.msg.Id = req.msg.Id
 	sending.Lock()
-	err = codec.Write(resp, reply, last)
+	err = cc.Write(resp.msg, reply)
 	sending.Unlock()
 	router.freeResponse(resp)
 	return err
 }
 
-func (s *service) call(ctx context.Context, router *router, sending *sync.Mutex, mtype *methodType, req *request, argv, replyv reflect.Value, codec serverCodec, ct string) {
+func (s *service) call(ctx context.Context, router *router, sending *sync.Mutex, mtype *methodType, req *request, argv, replyv reflect.Value, codec codec.Codec) {
 	function := mtype.method.Func
 	var returnValues []reflect.Value
 
 	r := &rpcRequest{
 		service:     router.name,
-		contentType: ct,
+		contentType: req.msg.Header["Content-Type"],
-		method:      req.ServiceMethod,
+		method:      req.msg.Method,
 	}
 
 	if !mtype.stream {
@@ -282,7 +284,7 @@ func (s *service) call(ctx context.Context, router *router, sending *sync.Mutex,
 		context: ctx,
 		codec:   codec,
 		request: r,
-		seq:     req.Seq,
+		id:      req.msg.Id,
 	}
 
 	// Invoke the method, providing a new value for the reply.
@@ -326,21 +328,21 @@ func (m *methodType) prepareContext(ctx context.Context) reflect.Value {
 	return reflect.Zero(m.ContextType)
 }
 
-func (router *router) ServeRequest(ctx context.Context, codec serverCodec, ct string) error {
+func (router *router) ServeRequest(ctx context.Context, cc codec.Codec) error {
 	sending := new(sync.Mutex)
-	service, mtype, req, argv, replyv, keepReading, err := router.readRequest(codec)
+	service, mtype, req, argv, replyv, keepReading, err := router.readRequest(cc)
 	if err != nil {
 		if !keepReading {
 			return err
 		}
 		// send a response if we actually managed to read a header.
 		if req != nil {
-			router.sendResponse(sending, req, invalidRequest, codec, err.Error(), true)
+			router.sendResponse(sending, req, invalidRequest, cc, err.Error(), true)
 			router.freeRequest(req)
 		}
 		return err
 	}
-	service.call(ctx, router, sending, mtype, req, argv, replyv, codec, ct)
+	service.call(ctx, router, sending, mtype, req, argv, replyv, cc)
 	return nil
 }
 
@@ -384,19 +386,19 @@ func (router *router) freeResponse(resp *response) {
 	router.respLock.Unlock()
 }
 
-func (router *router) readRequest(codec serverCodec) (service *service, mtype *methodType, req *request, argv, replyv reflect.Value, keepReading bool, err error) {
+func (router *router) readRequest(cc codec.Codec) (service *service, mtype *methodType, req *request, argv, replyv reflect.Value, keepReading bool, err error) {
-	service, mtype, req, keepReading, err = router.readHeader(codec)
+	service, mtype, req, keepReading, err = router.readHeader(cc)
 	if err != nil {
 		if !keepReading {
 			return
 		}
 		// discard body
-		codec.ReadBody(nil)
+		cc.ReadBody(nil)
 		return
 	}
 	// is it a streaming request? then we don't read the body
 	if mtype.stream {
-		codec.ReadBody(nil)
+		cc.ReadBody(nil)
 		return
 	}
 
@@ -409,7 +411,7 @@ func (router *router) readRequest(codec serverCodec) (service *service, mtype *m
 		argIsValue = true
 	}
 	// argv guaranteed to be a pointer now.
-	if err = codec.ReadBody(argv.Interface()); err != nil {
+	if err = cc.ReadBody(argv.Interface()); err != nil {
 		return
 	}
 	if argIsValue {
@@ -422,10 +424,14 @@ func (router *router) readRequest(codec serverCodec) (service *service, mtype *m
 	return
 }
 
-func (router *router) readHeader(codec serverCodec) (service *service, mtype *methodType, req *request, keepReading bool, err error) {
+func (router *router) readHeader(cc codec.Codec) (service *service, mtype *methodType, req *request, keepReading bool, err error) {
 	// Grab the request header.
+	msg := new(codec.Message)
+	msg.Type = codec.Request
 	req = router.getRequest()
-	err = codec.ReadHeader(req, true)
+	req.msg = msg
+
+	err = cc.ReadHeader(msg, msg.Type)
 	if err != nil {
 		req = nil
 		if err == io.EOF || err == io.ErrUnexpectedEOF {
@@ -439,9 +445,9 @@ func (router *router) readHeader(codec serverCodec) (service *service, mtype *me
 	// we can still recover and move on to the next request.
 	keepReading = true
 
-	serviceMethod := strings.Split(req.ServiceMethod, ".")
+	serviceMethod := strings.Split(req.msg.Method, ".")
 	if len(serviceMethod) != 2 {
-		err = errors.New("rpc: service/method request ill-formed: " + req.ServiceMethod)
+		err = errors.New("rpc: service/method request ill-formed: " + req.msg.Method)
 		return
 	}
 	// Look up the request.
@@ -449,12 +455,12 @@ func (router *router) readHeader(codec serverCodec) (service *service, mtype *me
 	service = router.serviceMap[serviceMethod[0]]
 	router.mu.Unlock()
 	if service == nil {
-		err = errors.New("rpc: can't find service " + req.ServiceMethod)
+		err = errors.New("rpc: can't find service " + req.msg.Method)
 		return
 	}
 	mtype = service.method[serviceMethod[1]]
 	if mtype == nil {
-		err = errors.New("rpc: can't find method " + req.ServiceMethod)
+		err = errors.New("rpc: can't find method " + req.msg.Method)
 	}
 	return
 }

server/rpc_server.go

@@ -45,7 +45,8 @@ func newRpcServer(opts ...Option) Server {
 	}
 }
 
-func (s *rpcServer) accept(sock transport.Socket) {
+// ServeConn serves a single connection
+func (s *rpcServer) ServeConn(sock transport.Socket) {
 	defer func() {
 		// close socket
 		sock.Close()
@@ -92,6 +93,7 @@ func (s *rpcServer) accept(sock transport.Socket) {
 
 		// no content type
 		if len(ct) == 0 {
+			msg.Header["Content-Type"] = DefaultContentType
 			ct = DefaultContentType
 		}
 
@@ -111,8 +113,16 @@ func (s *rpcServer) accept(sock transport.Socket) {
 		// create the internal server codec
 		codec := newRpcCodec(&msg, sock, cf)
 
+		// set router
+		var r Router
+		r = s.router
+
+		if s.opts.Router != nil {
+			r = s.opts.Router
+		}
+
 		// TODO: needs better error handling
-		if err := s.router.ServeRequest(ctx, codec, ct); err != nil {
+		if err := r.ServeRequest(ctx, codec); err != nil {
 			s.wg.Done()
 			log.Logf("Unexpected error serving request, closing socket: %v", err)
 			return
@@ -402,7 +412,7 @@ func (s *rpcServer) Start() error {
 
 	go func() {
 		for {
-			err := ts.Accept(s.accept)
+			err := ts.Accept(s.ServeConn)
 
 			// check if we're supposed to exit
 			select {

server/rpc_stream.go

@@ -3,16 +3,18 @@ package server
 import (
 	"context"
 	"sync"
+
+	"github.com/micro/go-micro/codec"
 )
 
 // Implements the Streamer interface
 type rpcStream struct {
 	sync.RWMutex
-	seq     uint64
+	id      string
 	closed  bool
 	err     error
 	request Request
-	codec   serverCodec
+	codec   codec.Codec
 	context context.Context
 }
 
@@ -28,28 +30,30 @@ func (r *rpcStream) Send(msg interface{}) error {
 	r.Lock()
 	defer r.Unlock()
 
-	resp := response{
+	resp := codec.Message{
-		ServiceMethod: r.request.Method(),
+		Method: r.request.Method(),
-		Seq:           r.seq,
+		Id:     r.id,
+		Type:   codec.Response,
 	}
 
-	return r.codec.Write(&resp, msg, false)
+	return r.codec.Write(&resp, msg)
 }
 
 func (r *rpcStream) Recv(msg interface{}) error {
 	r.Lock()
 	defer r.Unlock()
 
-	req := request{}
+	req := new(codec.Message)
+	req.Type = codec.Request
 
-	if err := r.codec.ReadHeader(&req, false); err != nil {
+	if err := r.codec.ReadHeader(req, req.Type); err != nil {
 		// discard body
 		r.codec.ReadBody(nil)
 		return err
 	}
 
 	// we need to stay up to date with sequence numbers
-	r.seq = req.Seq
+	r.id = req.Id
 	return r.codec.ReadBody(msg)
 }
 

server/server.go

@@ -30,7 +30,7 @@ type Server interface {
 
 // Router handle serving messages
 type Router interface {
-	ServeCodec(context.Context, codec.Codec) error
+	ServeRequest(context.Context, codec.Codec) error
 }
 
 // Message is an async message interface