106 lines
2.5 KiB
Go
106 lines
2.5 KiB
Go
package bchain
|
|
|
|
import (
|
|
"encoding/binary"
|
|
"time"
|
|
|
|
"github.com/golang/glog"
|
|
zmq "github.com/pebbe/zmq4"
|
|
)
|
|
|
|
// MQ is message queue listener handle
|
|
type MQ struct {
|
|
context *zmq.Context
|
|
socket *zmq.Socket
|
|
isRunning bool
|
|
finished chan bool
|
|
}
|
|
|
|
// MQMessage contains data received from Bitcoind message queue
|
|
type MQMessage struct {
|
|
Topic string
|
|
Sequence uint32
|
|
Body []byte
|
|
}
|
|
|
|
// NewMQ creates new Bitcoind ZeroMQ listener
|
|
// callback function receives messages
|
|
func NewMQ(binding string, callback func(*MQMessage)) (*MQ, error) {
|
|
context, err := zmq.NewContext()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
socket, err := context.NewSocket(zmq.SUB)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
err = socket.SetSubscribe("hashblock")
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
err = socket.SetSubscribe("hashtx")
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
// for now do not use raw subscriptions - we would have to handle skipped/lost notifications from zeromq
|
|
// on each notification we do sync or syncmempool respectively
|
|
// socket.SetSubscribe("rawblock")
|
|
// socket.SetSubscribe("rawtx")
|
|
err = socket.Connect(binding)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
glog.Info("MQ listening to ", binding)
|
|
mq := &MQ{context, socket, true, make(chan bool)}
|
|
go mq.run(callback)
|
|
return mq, nil
|
|
}
|
|
|
|
func (mq *MQ) run(callback func(*MQMessage)) {
|
|
mq.isRunning = true
|
|
for {
|
|
msg, err := mq.socket.RecvMessageBytes(0)
|
|
if err != nil {
|
|
if zmq.AsErrno(err) == zmq.Errno(zmq.ETERM) || err.Error() == "Socket is closed" {
|
|
close(mq.finished)
|
|
glog.Info("MQ loop terminated")
|
|
break
|
|
}
|
|
glog.Error("MQ RecvMessageBytes error ", err, ", ", zmq.AsErrno(err))
|
|
time.Sleep(100 * time.Millisecond)
|
|
}
|
|
if msg != nil && len(msg) >= 3 {
|
|
sequence := uint32(0)
|
|
if len(msg[len(msg)-1]) == 4 {
|
|
sequence = binary.LittleEndian.Uint32(msg[len(msg)-1])
|
|
}
|
|
m := &MQMessage{
|
|
Topic: string(msg[0]),
|
|
Sequence: sequence,
|
|
Body: msg[1],
|
|
}
|
|
callback(m)
|
|
}
|
|
}
|
|
mq.isRunning = false
|
|
}
|
|
|
|
// Shutdown stops listening to the ZeroMQ and closes the connection
|
|
func (mq *MQ) Shutdown() error {
|
|
glog.Info("MQ server shutdown")
|
|
if mq.isRunning {
|
|
mq.socket.SetUnsubscribe("hashtx")
|
|
mq.socket.SetUnsubscribe("hashblock")
|
|
// if errors in socket.Close or context.Term, let it close ungracefully
|
|
if err := mq.socket.Close(); err != nil {
|
|
return err
|
|
}
|
|
if err := mq.context.Term(); err != nil {
|
|
return err
|
|
}
|
|
_, _ = <-mq.finished
|
|
glog.Info("MQ server shutdown finished")
|
|
}
|
|
return nil
|
|
}
|