// Internal goroutine that reads from the socket and writes events to
// the channel
func (mc *Client) runFeed(ch chan TapEvent, feed *TapFeed) {
defer close(ch)
var headerBuf [gomemcached.HDR_LEN]byte
loop:
for {
// Read the next request from the server.
//
// (Can't call mc.Receive() because it reads a
// _response_ not a request.)
var pkt gomemcached.MCRequest
err := pkt.Receive(mc.conn, headerBuf[:])
if err != nil {
if err != io.EOF {
feed.Error = err
}
break loop
}
//log.Printf("** TapFeed received %#v : %q", pkt, pkt.Body)
if pkt.Opcode == gomemcached.TAP_CONNECT {
// This is not an event from the server; it's
// an error response to my connect request.
feed.Error = fmt.Errorf("Tap connection failed: %s", pkt.Body)
break loop
}
event := makeTapEvent(pkt)
if event != nil {
if event.Opcode == tapEndStream {
break loop
}
select {
case ch <- *event:
case <-feed.closer:
break loop
}
}
if len(pkt.Extras) >= 4 {
reqFlags := binary.BigEndian.Uint16(pkt.Extras[2:])
if reqFlags&gomemcached.TAP_ACK != 0 {
mc.sendAck(&pkt)
}
}
}
mc.Close()
}
func TestTransmitReq(t *testing.T) {
b := bytes.NewBuffer([]byte{})
buf := bufio.NewWriter(b)
req := gomemcached.MCRequest{
Opcode: gomemcached.SET,
Cas: 938424885,
Opaque: 7242,
VBucket: 824,
Extras: []byte{},
Key: []byte("somekey"),
Body: []byte("somevalue"),
}
// Verify nil transmit is OK
err := transmitRequest(nil, &req)
if err != noConn {
t.Errorf("Expected noConn with no conn, got %v", err)
}
err = transmitRequest(buf, &req)
if err != nil {
t.Fatalf("Error transmitting request: %v", err)
}
buf.Flush()
expected := []byte{
gomemcached.REQ_MAGIC, byte(gomemcached.SET),
0x0, 0x7, // length of key
0x0, // extra length
0x0, // reserved
0x3, 0x38, // vbucket
0x0, 0x0, 0x0, 0x10, // Length of value
0x0, 0x0, 0x1c, 0x4a, // opaque
0x0, 0x0, 0x0, 0x0, 0x37, 0xef, 0x3a, 0x35, // CAS
's', 'o', 'm', 'e', 'k', 'e', 'y',
's', 'o', 'm', 'e', 'v', 'a', 'l', 'u', 'e'}
if len(b.Bytes()) != req.Size() {
t.Fatalf("Expected %v bytes, got %v", req.Size(),
len(b.Bytes()))
}
if !reflect.DeepEqual(b.Bytes(), expected) {
t.Fatalf("Expected:\n%#v\n -- got -- \n%#v",
expected, b.Bytes())
}
}
func BenchmarkTransmitReqNull(b *testing.B) {
req := gomemcached.MCRequest{
Opcode: gomemcached.SET,
Cas: 938424885,
Opaque: 7242,
VBucket: 824,
Extras: []byte{},
Key: []byte("somekey"),
Body: []byte("somevalue"),
}
b.SetBytes(int64(req.Size()))
for i := 0; i < b.N; i++ {
err := transmitRequest(ioutil.Discard, &req)
if err != nil {
b.Fatalf("Error transmitting request: %v", err)
}
}
}
func BenchmarkTransmitReqLarge(b *testing.B) {
bout := bytes.NewBuffer([]byte{})
req := gomemcached.MCRequest{
Opcode: gomemcached.SET,
Cas: 938424885,
Opaque: 7242,
VBucket: 824,
Extras: []byte{},
Key: []byte("somekey"),
Body: make([]byte, 24*1024),
}
b.SetBytes(int64(req.Size()))
for i := 0; i < b.N; i++ {
bout.Reset()
buf := bufio.NewWriterSize(bout, req.Size()*2)
err := transmitRequest(buf, &req)
if err != nil {
b.Fatalf("Error transmitting request: %v", err)
}
}
}
func transmitRequest(o io.Writer, req *gomemcached.MCRequest) (err error) {
if o == nil {
return noConn
}
return req.Transmit(o)
}