micro/client/rpc_stream.go

125 lines
2.1 KiB
Go

package client
import (
"errors"
"io"
"log"
"sync"
"golang.org/x/net/context"
)
// Implements the streamer interface
type rpcStream struct {
sync.RWMutex
seq uint64
once sync.Once
closed chan bool
err error
request Request
codec clientCodec
context context.Context
}
func (r *rpcStream) isClosed() bool {
select {
case _, ok := <-r.closed:
if !ok {
return true
}
default:
}
return false
}
func (r *rpcStream) Context() context.Context {
return r.context
}
func (r *rpcStream) Request() Request {
return r.request
}
func (r *rpcStream) Send(msg interface{}) error {
r.Lock()
defer r.Unlock()
if r.isClosed() {
r.err = errShutdown
return errShutdown
}
seq := r.seq
r.seq++
req := request{
Service: r.request.Service(),
Seq: seq,
ServiceMethod: r.request.Method(),
}
if err := r.codec.WriteRequest(&req, msg); err != nil {
r.err = err
return err
}
return nil
}
func (r *rpcStream) Recv(msg interface{}) error {
r.Lock()
defer r.Unlock()
if r.isClosed() {
r.err = errShutdown
return errShutdown
}
var resp response
if err := r.codec.ReadResponseHeader(&resp); err != nil {
if err == io.EOF && !r.isClosed() {
r.err = io.ErrUnexpectedEOF
return io.ErrUnexpectedEOF
}
r.err = err
return err
}
switch {
case len(resp.Error) > 0:
// We've got an error response. Give this to the request;
// any subsequent requests will get the ReadResponseBody
// error if there is one.
if resp.Error != lastStreamResponseError {
r.err = serverError(resp.Error)
} else {
r.err = io.EOF
}
if err := r.codec.ReadResponseBody(nil); err != nil {
r.err = errors.New("reading error payload: " + err.Error())
}
default:
if err := r.codec.ReadResponseBody(msg); err != nil {
r.err = errors.New("reading body " + err.Error())
}
}
if r.err != nil && r.err != io.EOF && !r.isClosed() {
log.Println("rpc: client protocol error:", r.err)
}
return r.err
}
func (r *rpcStream) Error() error {
r.RLock()
defer r.RUnlock()
return r.err
}
func (r *rpcStream) Close() error {
r.once.Do(func() {
close(r.closed)
})
return r.codec.Close()
}