// recvResponse receives and parses an RPC response.
// On error, it returns the error and indicates whether the call should be retried.
//
// TODO(zhaoq): Check whether the received message sequence is valid.
func recvResponse(dopts dialOptions, t transport.ClientTransport, c *callInfo, stream *transport.Stream, reply interface{}) error {
// Try to acquire header metadata from the server if there is any.
var err error
defer func() {
if err != nil {
if _, ok := err.(transport.ConnectionError); !ok {
t.CloseStream(stream, err)
}
}
}()
c.headerMD, err = stream.Header()
if err != nil {
return err
}
p := &parser{r: stream}
for {
if err = recv(p, dopts.codec, stream, dopts.dc, reply, math.MaxInt32); err != nil {
if err == io.EOF {
break
}
return err
}
}
c.trailerMD = stream.Trailer()
return nil
}
// recvResponse receives and parses an RPC response.
// On error, it returns the error and indicates whether the call should be retried.
//
// TODO(zhaoq): Check whether the received message sequence is valid.
func recvResponse(dopts dialOptions, t transport.ClientTransport, c *callInfo, stream *transport.Stream, reply interface{}) error {
// Try to acquire header metadata from the server if there is any.
// 如何接受请求呢?
// 1. 和处理的Http请求类似, 首先是: 处理Header
var err error
c.headerMD, err = stream.Header()
if err != nil {
return err
}
// 2. 然后处理stream
p := &parser{r: stream}
for {
// stream --> (parser) --> msg --> decompress --> unmarshal --> reply
// Iter 1: 读取到Reply
// Iter 2: 读取失败，碰到EOF
if err = recv(p, dopts.codec, stream, dopts.dc, reply); err != nil {
// 似乎需要等待stream的EOF
if err == io.EOF {
break
}
return err
}
}
// 3. 获取Trailer?
c.trailerMD = stream.Trailer()
return nil
}
// recvResponse receives and parses an RPC response.
// On error, it returns the error and indicates whether the call should be retried.
//
// TODO(zhaoq): Check whether the received message sequence is valid.
func recvResponse(dopts dialOptions, t transport.ClientTransport, c *callInfo, stream *transport.Stream, reply interface{}) error {
// Try to acquire header metadata from the server if there is any.
var err error
c.headerMD, err = stream.Header()
if err != nil {
return err
}
p := &parser{r: stream}
for {
if err = recv(p, dopts.codec, stream, dopts.dc, reply); err != nil {
if err == io.EOF {
break
}
return err
}
}
c.trailerMD = stream.Trailer()
return nil
}
// recv receives and parses an RPC response.
// On error, it returns the error and indicates whether the call should be retried.
//
// TODO(zhaoq): Check whether the received message sequence is valid.
func recv(t transport.ClientTransport, c *callInfo, stream *transport.Stream, reply proto.Message) error {
// Try to acquire header metadata from the server if there is any.
var err error
c.headerMD, err = stream.Header()
if err != nil {
return err
}
p := &parser{s: stream}
for {
if err = recvProto(p, reply); err != nil {
if err == io.EOF {
break
}
return err
}
}
c.trailerMD = stream.Trailer()
return nil
}
// recvResponse receives and parses an RPC response.
// On error, it returns the error and indicates whether the call should be retried.
//
// TODO(zhaoq): Check whether the received message sequence is valid.
// TODO ctx is used for stats collection and processing. It is the context passed from the application.
func recvResponse(ctx context.Context, dopts dialOptions, t transport.ClientTransport, c *callInfo, stream *transport.Stream, reply interface{}) (err error) {
// Try to acquire header metadata from the server if there is any.
defer func() {
if err != nil {
if _, ok := err.(transport.ConnectionError); !ok {
t.CloseStream(stream, err)
}
}
}()
c.headerMD, err = stream.Header()
if err != nil {
return
}
p := &parser{r: stream}
var inPayload *stats.InPayload
if stats.On() {
inPayload = &stats.InPayload{
Client: true,
}
}
for {
if err = recv(p, dopts.codec, stream, dopts.dc, reply, math.MaxInt32, inPayload); err != nil {
if err == io.EOF {
break
}
return
}
}
if inPayload != nil && err == io.EOF && stream.StatusCode() == codes.OK {
// TODO in the current implementation, inTrailer may be handled before inPayload in some cases.
// Fix the order if necessary.
stats.Handle(ctx, inPayload)
}
c.trailerMD = stream.Trailer()
return nil
}