// NewClientStream creates a new Stream for the client side. This is called
// by generated code.
func NewClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, method string, opts ...CallOption) (ClientStream, error) {
var (
t transport.ClientTransport
err error
)
t, err = cc.dopts.picker.Pick(ctx)
if err != nil {
return nil, toRPCErr(err)
}
// TODO(zhaoq): CallOption is omitted. Add support when it is needed.
callHdr := &transport.CallHdr{
Host: cc.authority,
Method: method,
}
cs := &clientStream{
desc: desc,
codec: cc.dopts.codec,
tracing: EnableTracing,
}
if cs.tracing {
cs.trInfo.tr = trace.New("grpc.Sent."+methodFamily(method), method)
cs.trInfo.firstLine.client = true
if deadline, ok := ctx.Deadline(); ok {
cs.trInfo.firstLine.deadline = deadline.Sub(time.Now())
}
cs.trInfo.tr.LazyLog(&cs.trInfo.firstLine, false)
ctx = trace.NewContext(ctx, cs.trInfo.tr)
}
s, err := t.NewStream(ctx, callHdr)
if err != nil {
return nil, toRPCErr(err)
}
cs.t = t
cs.s = s
cs.p = &parser{s: s}
// Listen on ctx.Done() to detect cancellation when there is no pending
// I/O operations on this stream.
go func() {
<-s.Context().Done()
cs.closeTransportStream(transport.ContextErr(s.Context().Err()))
}()
return cs, nil
}
// Invoke is called by the generated code. It sends the RPC request on the
// wire and returns after response is received.
func Invoke(ctx context.Context, method string, args, reply interface{}, cc *ClientConn, opts ...CallOption) (err error) {
var c callInfo
for _, o := range opts {
if err := o.before(&c); err != nil {
return toRPCErr(err)
}
}
defer func() {
for _, o := range opts {
o.after(&c)
}
}()
if EnableTracing {
c.traceInfo.tr = trace.New("grpc.Sent."+methodFamily(method), method)
defer c.traceInfo.tr.Finish()
c.traceInfo.firstLine.client = true
if deadline, ok := ctx.Deadline(); ok {
c.traceInfo.firstLine.deadline = deadline.Sub(time.Now())
}
c.traceInfo.tr.LazyLog(&c.traceInfo.firstLine, false)
// TODO(dsymonds): Arrange for c.traceInfo.firstLine.remoteAddr to be set.
defer func() {
if err != nil {
c.traceInfo.tr.LazyLog(&fmtStringer{"%v", []interface{}{err}}, true)
c.traceInfo.tr.SetError()
}
}()
}
topts := &transport.Options{
Last: true,
Delay: false,
}
var (
lastErr error // record the error that happened
)
for {
var (
err error
t transport.ClientTransport
stream *transport.Stream
)
// TODO(zhaoq): Need a formal spec of retry strategy for non-failfast rpcs.
if lastErr != nil && c.failFast {
return toRPCErr(lastErr)
}
callHdr := &transport.CallHdr{
Host: cc.authority,
Method: method,
}
t, err = cc.dopts.picker.Pick(ctx)
if err != nil {
if lastErr != nil {
// This was a retry; return the error from the last attempt.
return toRPCErr(lastErr)
}
return toRPCErr(err)
}
if c.traceInfo.tr != nil {
c.traceInfo.tr.LazyLog(&payload{sent: true, msg: args}, true)
}
stream, err = sendRequest(ctx, cc.dopts.codec, callHdr, t, args, topts)
if err != nil {
if _, ok := err.(transport.ConnectionError); ok {
lastErr = err
continue
}
if lastErr != nil {
return toRPCErr(lastErr)
}
return toRPCErr(err)
}
// Receive the response
lastErr = recvResponse(cc.dopts.codec, t, &c, stream, reply)
if _, ok := lastErr.(transport.ConnectionError); ok {
continue
}
if c.traceInfo.tr != nil {
c.traceInfo.tr.LazyLog(&payload{sent: false, msg: reply}, true)
}
t.CloseStream(stream, lastErr)
if lastErr != nil {
return toRPCErr(lastErr)
}
return Errorf(stream.StatusCode(), stream.StatusDesc())
}
}
// Serve accepts incoming connections on the listener lis, creating a new
// ServerTransport and service goroutine for each. The service goroutines
// read gRPC request and then call the registered handlers to reply to them.
// Service returns when lis.Accept fails.
func (s *Server) Serve(lis net.Listener) error {
s.mu.Lock()
s.printf("serving")
if s.lis == nil {
s.mu.Unlock()
return ErrServerStopped
}
s.lis[lis] = true
s.mu.Unlock()
defer func() {
lis.Close()
s.mu.Lock()
delete(s.lis, lis)
s.mu.Unlock()
}()
for {
c, err := lis.Accept()
if err != nil {
s.mu.Lock()
s.printf("done serving; Accept = %v", err)
s.mu.Unlock()
return err
}
var authInfo credentials.AuthInfo
if creds, ok := s.opts.creds.(credentials.TransportAuthenticator); ok {
var conn net.Conn
conn, authInfo, err = creds.ServerHandshake(c)
if err != nil {
s.mu.Lock()
s.errorf("ServerHandshake(%q) failed: %v", c.RemoteAddr(), err)
s.mu.Unlock()
grpclog.Println("grpc: Server.Serve failed to complete security handshake.")
continue
}
c = conn
}
s.mu.Lock()
if s.conns == nil {
s.mu.Unlock()
c.Close()
return nil
}
st, err := transport.NewServerTransport("http2", c, s.opts.maxConcurrentStreams, authInfo)
if err != nil {
s.errorf("NewServerTransport(%q) failed: %v", c.RemoteAddr(), err)
s.mu.Unlock()
c.Close()
grpclog.Println("grpc: Server.Serve failed to create ServerTransport: ", err)
continue
}
s.conns[st] = true
s.mu.Unlock()
go func() {
var wg sync.WaitGroup
st.HandleStreams(func(stream *transport.Stream) {
var trInfo *traceInfo
if EnableTracing {
trInfo = &traceInfo{
tr: trace.New("grpc.Recv."+methodFamily(stream.Method()), stream.Method()),
}
trInfo.firstLine.client = false
trInfo.firstLine.remoteAddr = st.RemoteAddr()
stream.TraceContext(trInfo.tr)
if dl, ok := stream.Context().Deadline(); ok {
trInfo.firstLine.deadline = dl.Sub(time.Now())
}
}
wg.Add(1)
go func() {
s.handleStream(st, stream, trInfo)
wg.Done()
}()
})
wg.Wait()
s.mu.Lock()
delete(s.conns, st)
s.mu.Unlock()
}()
}
}