// ZmqRecvMulti Receives a multi-part message and return it as a slice of strings
func ZmqRecvMulti(s *zmq.Socket) []string {
var msg []string
more := true
for more {
part, _ := s.Recv(0)
msg = append(msg, part)
more, _ = s.GetRcvmore()
}
return msg
}
func RecieveClientRequest(receiver *zmq.Socket, myservices map[string]ProcessRequest) (service_required ProcessRequest, message string, err error) {
for count := 0; ; count++ {
var request string
request, err = receiver.Recv(0)
if err != nil {
err = errors.New(fmt.Sprintf("Error:Receive:%s", err))
return
}
fmt.Println("\tCurrent: ", request)
// Retrieve message parts from the envelope
// The first part is either:
// a. A heartbeat request
// b. The service's SID
// The second part: the message
if count == 0 {
var isPresent bool
service_required, isPresent = myservices[request]
fmt.Printf("%s is present? %s", request, isPresent)
if !isPresent {
err = errors.New("Error:InvalidService")
return
}
}
if count == 1 {
message = request
}
// Check if there are more in envelope and deal with any errors
var more bool
more, err = receiver.GetRcvmore()
if err != nil {
err = errors.New(fmt.Sprintf("Error:Receive:%s", err))
return
}
if !more {
return
}
}
}
func dump(soc *zmq.Socket) {
fmt.Println("----------------------------------------")
for {
// Process all parts of the message
message, _ := soc.Recv(0)
// Dump the message as text or binary
fmt.Printf("[%03d] ", len(message))
if all_char.MatchString(message) {
fmt.Print(message)
} else {
for i := 0; i < len(message); i++ {
fmt.Printf("%02X ", message[i])
}
}
fmt.Println()
more, _ := soc.GetRcvmore()
if !more {
break
}
}
}
func TestDisconnectInproc(t *testing.T) {
var pubSocket, subSocket *zmq.Socket
defer func() {
for _, s := range []*zmq.Socket{pubSocket, subSocket} {
if s != nil {
s.SetLinger(0)
s.Close()
}
}
}()
publicationsReceived := 0
isSubscribed := false
pubSocket, err := zmq.NewSocket(zmq.XPUB)
if err != nil {
t.Fatal("NewSocket XPUB:", err)
}
subSocket, err = zmq.NewSocket(zmq.SUB)
if err != nil {
t.Fatal("NewSocket SUB:", err)
}
err = subSocket.SetSubscribe("foo")
if err != nil {
t.Fatal("subSocket.SetSubscribe:", err)
}
err = pubSocket.Bind("inproc://someInProcDescriptor")
if err != nil {
t.Fatal("pubSocket.Bind:", err)
}
iteration := 0
poller := zmq.NewPoller()
poller.Add(subSocket, zmq.POLLIN) // read publications
poller.Add(pubSocket, zmq.POLLIN) // read subscriptions
for {
sockets, err := poller.Poll(100 * time.Millisecond)
if err != nil {
t.Error("Poll:", err)
break // Interrupted
}
for _, socket := range sockets {
if socket.Socket == pubSocket {
for {
buffer, err := pubSocket.Recv(0)
if err != nil {
t.Fatal("pubSocket.Recv", err)
}
exp := "\x01foo"
if isSubscribed {
exp = "\x00foo"
}
if buffer != exp {
t.Errorf("pubSocket.Recv: expected %q, got %q", exp, buffer)
}
if buffer[0] == 0 {
if isSubscribed != true {
t.Errorf("Poller: expected subscribed")
}
isSubscribed = false
} else {
if isSubscribed != false {
t.Errorf("Poller: expected not subscribed")
}
isSubscribed = true
}
more, err := pubSocket.GetRcvmore()
if err != nil {
t.Fatal("pubSocket.GetRcvmore:", err)
}
if !more {
break // Last message part
}
}
break
}
}
for _, socket := range sockets {
if socket.Socket == subSocket {
for _, exp := range []string{"foo", "this is foo!", "", ""} {
msg, err := subSocket.Recv(0)
if err != nil {
t.Fatal("subSocket.Recv:", err)
}
if msg != exp {
t.Errorf("subSocket.Recv: expected %q, got %q", exp, msg)
}
more, err := subSocket.GetRcvmore()
if err != nil {
t.Fatal("subSocket.GetRcvmore:", err)
}
if !more {
publicationsReceived++
break // Last message part
}
}
break
}
}
if iteration == 1 {
err := subSocket.Connect("inproc://someInProcDescriptor")
if err != nil {
t.Fatal("subSocket.Connect", err)
}
}
if iteration == 4 {
err := subSocket.Disconnect("inproc://someInProcDescriptor")
if err != nil {
t.Fatal("subSocket.Disconnect", err)
}
}
if iteration > 4 && len(sockets) == 0 {
break
}
_, err = pubSocket.Send("foo", zmq.SNDMORE)
if err != nil {
t.Fatal("pubSocket.Send 1", err)
}
_, err = pubSocket.Send("this is foo!", 0)
if err != nil {
t.Fatal("pubSocket.Send 2", err)
}
iteration++
}
if publicationsReceived != 3 {
t.Error("publicationsReceived != 3 ")
}
if isSubscribed {
t.Error("isSubscribed")
}
err = pubSocket.Close()
pubSocket = nil
if err != nil {
t.Error("pubSocket.Close:", err)
}
err = subSocket.Close()
subSocket = nil
if err != nil {
t.Error("subSocket.Close:", err)
}
}
func bounce(server, client *zmq.Socket) (msg string, err error) {
content := "12345678ABCDEFGH12345678abcdefgh"
// Send message from client to server
rc, err := client.Send(content, zmq.SNDMORE|zmq.DONTWAIT)
if err != nil {
return "client.Send SNDMORE|DONTWAIT:", err
}
if rc != 32 {
return "client.Send SNDMORE|DONTWAIT:", err32
}
rc, err = client.Send(content, zmq.DONTWAIT)
if err != nil {
return "client.Send DONTWAIT:", err
}
if rc != 32 {
return "client.Send DONTWAIT:", err32
}
// Receive message at server side
msg, err = server.Recv(0)
if err != nil {
return "server.Recv 1:", err
}
// Check that message is still the same
if msg != content {
return "server.Recv 1:", errors.New(fmt.Sprintf("%q != %q", msg, content))
}
rcvmore, err := server.GetRcvmore()
if err != nil {
return "server.GetRcvmore 1:", err
}
if !rcvmore {
return "server.GetRcvmore 1:", errors.New(fmt.Sprint("rcvmore ==", rcvmore))
}
// Receive message at server side
msg, err = server.Recv(0)
if err != nil {
return "server.Recv 2:", err
}
// Check that message is still the same
if msg != content {
return "server.Recv 2:", errors.New(fmt.Sprintf("%q != %q", msg, content))
}
rcvmore, err = server.GetRcvmore()
if err != nil {
return "server.GetRcvmore 2:", err
}
if rcvmore {
return "server.GetRcvmore 2:", errors.New(fmt.Sprint("rcvmore == ", rcvmore))
}
// The same, from server back to client
// Send message from server to client
rc, err = server.Send(content, zmq.SNDMORE)
if err != nil {
return "server.Send SNDMORE:", err
}
if rc != 32 {
return "server.Send SNDMORE:", err32
}
rc, err = server.Send(content, 0)
if err != nil {
return "server.Send 0:", err
}
if rc != 32 {
return "server.Send 0:", err32
}
// Receive message at client side
msg, err = client.Recv(0)
if err != nil {
return "client.Recv 1:", err
}
// Check that message is still the same
if msg != content {
return "client.Recv 1:", errors.New(fmt.Sprintf("%q != %q", msg, content))
}
rcvmore, err = client.GetRcvmore()
if err != nil {
return "client.GetRcvmore 1:", err
}
if !rcvmore {
return "client.GetRcvmore 1:", errors.New(fmt.Sprint("rcvmore ==", rcvmore))
}
// Receive message at client side
msg, err = client.Recv(0)
if err != nil {
return "client.Recv 2:", err
}
// Check that message is still the same
if msg != content {
return "client.Recv 2:", errors.New(fmt.Sprintf("%q != %q", msg, content))
}
rcvmore, err = client.GetRcvmore()
if err != nil {
return "client.GetRcvmore 2:", err
}
if rcvmore {
return "client.GetRcvmore 2:", errors.New(fmt.Sprint("rcvmore == ", rcvmore))
}
return "OK", nil
}
// Send a request to a service
func SendRequest(service Service, request, message string) (reply []string, err error) {
// Bind to service if not already done
var requester *zmq.Socket
fmt.Println("Connecting to '", service.Name, "'' at '", service.Address, "'...")
requester, err = zmq.NewSocket(zmq.REQ)
if err != nil {
log.Println(err)
return
}
requester.Connect(service.Address)
poller := zmq.NewPoller()
poller.Add(requester, zmq.POLLIN)
retries_left := REQUEST_RETRIES
request_timeout := REQUEST_TIMEOUT
if request == PPP_HEARTBEAT {
retries_left = 1
request_timeout = 1500 * time.Millisecond
}
for retries_left > 0 {
// Send message
// The service required in first packet of envelope
// The message for given service in second packet of envelope
// Heartbeat messages only contain one message in envelope
if request == PPP_HEARTBEAT {
_, err = requester.Send(PPP_HEARTBEAT, 0)
} else {
_, err = requester.Send(request, zmq.SNDMORE)
_, err = requester.Send(message, 0)
}
for expect_reply := true; expect_reply; {
// Poll socket for a reply, with timeout
var sockets []zmq.Polled
sockets, err = poller.Poll(request_timeout)
if err != nil {
break // Interrupted
}
// Wait to receive reply if there are no more messages to send
if len(sockets) > 0 {
// Receive all replies in the envelope before processing
var more bool
for count := 0; ; count++ {
var rep string
rep, err = requester.Recv(0)
if err != nil {
retries_left--
break
}
reply = append(reply, rep)
// Unpacking three parts from the message envelope
// The first part: the expected service reply signature
// The second part is either:
// a. error state (empty if no error) OR
// b. the heartbeat reply of the server
// The third part: the actual message
if count == 0 && rep != service.Reply {
err = errors.New("ServiceListOutdated:Bound to wrong service")
retries_left = 0
break
}
if count == 1 && rep != "" && rep != PPP_READY {
err = errors.New(rep)
retries_left = 0
break
}
// Break from loop if there are no more messages or
// an error condition occurs
more, err = requester.GetRcvmore()
if !more || err != nil {
retries_left--
break
}
}
// If there was an error retrieving the message, then we
// should still expect replies
if err != nil {
break
}
// All messages retrieved from packet successfully
// Leave the retrieve/retry loops
retries_left = 0
expect_reply = false
} else {
retries_left--
if retries_left == 0 {
if err == nil {
err = errors.New("Error:TimeOut")
}
requester.Close()
return
} else {
err = nil
reply = nil
fmt.Println("No response from server, retrying...")
// Old socket is confused; close it and open a new one
requester.Close()
requester, _ = zmq.NewSocket(zmq.REQ)
requester.Connect(service.Address)
// Recreate poller for new client
poller = zmq.NewPoller()
poller.Add(requester, zmq.POLLIN)
// Send request again, on the new socket
if request == PPP_HEARTBEAT {
_, err = requester.Send(PPP_HEARTBEAT, 0)
} else {
_, err = requester.Send(request, zmq.SNDMORE)
_, err = requester.Send(message, 0)
}
}
}
}
}
fmt.Println("\tReceived: ", reply)
// Deall with invalid/distorted replies first
// Followed by heartbeat replies
// Then package reply for return to the function caller
if len(reply) < 2 {
err = errors.New(fmt.Sprintf("Error:UnexpectedReply:%s", err))
requester.Close()
return
}
if reply[1] == PPP_READY {
reply = append(reply, reply[1])
}
reply = reply[2:]
requester.Close()
return
}
func (w *worker) socketLoop(s *zmq.Socket, send <-chan Data, recv chan<- Data, state zmq.State) {
if recv != nil {
defer close(recv)
}
var (
sendBuf Data
sendPending bool
recvBuf Data
recvPending bool
)
for {
var (
err error
sendActive <-chan Data
recvActive chan<- Data
)
if !sendPending {
sendActive = send
}
if recvPending {
recvActive = recv
}
select {
case <-w.notifier:
const fullState = zmq.POLLIN | zmq.POLLOUT
if state&fullState != fullState {
if state, err = s.GetEvents(); err != nil {
handleGeneralError(err)
return
}
}
case <-w.closer:
return
case sendBuf, sendPending = <-sendActive:
if !sendPending {
send = nil
}
case recvActive <- recvBuf:
recvPending = false
recvBuf.Bytes = nil
}
for {
loop := false
if sendPending && state&zmq.POLLOUT != 0 {
flags := zmq.DONTWAIT
if sendBuf.More {
flags |= zmq.SNDMORE
}
if _, err = s.SendBytes(sendBuf.Bytes, flags); err == nil {
sendPending = false
sendBuf.Bytes = nil
loop = true
} else if !handleIOError(err) {
return
}
if state, err = s.GetEvents(); err != nil {
handleGeneralError(err)
return
}
}
if !recvPending && state&zmq.POLLIN != 0 {
if data, err := s.RecvBytes(zmq.DONTWAIT); err == nil {
if more, err := s.GetRcvmore(); err == nil {
recvBuf.Bytes = data
recvBuf.More = more
recvPending = true
loop = true
} else {
handleGeneralError(err)
return
}
} else if !handleIOError(err) {
return
}
if state, err = s.GetEvents(); err != nil {
handleGeneralError(err)
return
}
}
if !loop {
break
}
}
}
}
func bounce(server, client *zmq.Socket, willfail bool) {
content := "12345678ABCDEFGH12345678abcdefgh"
// Send message from client to server
rc, err := client.Send(content, zmq.SNDMORE|zmq.DONTWAIT)
if checkErr0(err, 1) {
return
}
if rc != 32 {
checkErr0(errors.New("rc != 32"), 2)
}
rc, err = client.Send(content, zmq.DONTWAIT)
if checkErr0(err, 3) {
return
}
if rc != 32 {
checkErr0(errors.New("rc != 32"), 4)
}
// Receive message at server side
msg, err := server.Recv(0)
if checkErr0(e(err, willfail), 5) {
return
}
// Check that message is still the same
if msg != content {
checkErr0(errors.New(fmt.Sprintf("%q != %q", msg, content)), 6)
}
rcvmore, err := server.GetRcvmore()
if checkErr0(err, 7) {
return
}
if !rcvmore {
checkErr0(errors.New(fmt.Sprint("rcvmore ==", rcvmore)), 8)
return
}
// Receive message at server side
msg, err = server.Recv(0)
if checkErr0(err, 9) {
return
}
// Check that message is still the same
if msg != content {
checkErr0(errors.New(fmt.Sprintf("%q != %q", msg, content)), 10)
}
rcvmore, err = server.GetRcvmore()
if checkErr0(err, 11) {
return
}
if rcvmore {
checkErr0(errors.New(fmt.Sprint("rcvmore == ", rcvmore)), 12)
return
}
// The same, from server back to client
// Send message from server to client
rc, err = server.Send(content, zmq.SNDMORE)
if checkErr0(err, 13) {
return
}
if rc != 32 {
checkErr0(errors.New("rc != 32"), 14)
}
rc, err = server.Send(content, 0)
if checkErr0(err, 15) {
return
}
if rc != 32 {
checkErr0(errors.New("rc != 32"), 16)
}
// Receive message at client side
msg, err = client.Recv(0)
if checkErr0(err, 17) {
return
}
// Check that message is still the same
if msg != content {
checkErr0(errors.New(fmt.Sprintf("%q != %q", msg, content)), 18)
}
rcvmore, err = client.GetRcvmore()
if checkErr0(err, 19) {
return
}
if !rcvmore {
checkErr0(errors.New(fmt.Sprint("rcvmore ==", rcvmore)), 20)
return
}
// Receive message at client side
msg, err = client.Recv(0)
if checkErr0(err, 21) {
return
}
// Check that message is still the same
if msg != content {
checkErr0(errors.New(fmt.Sprintf("%q != %q", msg, content)), 22)
}
rcvmore, err = client.GetRcvmore()
if checkErr0(err, 23) {
return
}
if rcvmore {
checkErr0(errors.New(fmt.Sprint("rcvmore == ", rcvmore)), 24)
return
}
}
func serveFrontend(frontend *zmq.Socket) (back *zmq.Socket) {
var header []string
var service Service
isPresent := false
//fmt.Println("\nReceiving message from client...")
for {
msg, _ := frontend.Recv(0)
//fmt.Printf("\tIn-->%s\n", msg)
message := strings.SplitN(msg, ":", 2)
if more, _ := frontend.GetRcvmore(); more {
// If this part of the message contains no service description
// treat is as a header
if len(message) != 2 {
header = append(header, msg)
continue
}
// If the service request is to register a service, register it
if message[0] == "register" {
back = registerService(message[1], header, frontend)
return
}
// If the service requested is not in the service list then assume
// it will be at end of message and treat message as part of header
service, isPresent = services[message[0]]
if !isPresent {
header = append(header, msg)
continue
}
// If the service requested is available send the early parts of
// message at this point
for key := range header {
//fmt.Printf("\tForwarding to %s at %s: %s\n", service.Name, service.Address, header[key])
service.Backend.Send(header[key], zmq.SNDMORE)
}
header = header[:0] // Empty header to avoid accidental resend below
service.Backend.Send(message[1], zmq.SNDMORE)
} else {
// If the service request is to register a service, register it
if message[0] == "register" {
back = registerService(message[1], header, frontend)
return
}
// Has the service already been discovered? -If not, discover it
if !isPresent {
service, isPresent = services[message[0]]
}
// If the service is still not discovered at this point, then we
// have a problem. Report back to client
if !isPresent {
sendToClient("InvalidService", header, "Invalid Service SID", 0, frontend)
break
}
// Otherwise everything is good fetch the service and send request
// Send the assumed header of the message
for key := range header {
//fmt.Printf("\tForwarding to %s at %s: %s\n", service.Name, service.Address, header[key])
service.Backend.Send(header[key], zmq.SNDMORE)
}
// Send the rest of the message
//fmt.Printf("\tForwarding to %s at %s: %s\n", service.Name, service.Address, message[1])
service.Backend.Send(message[1], 0)
//fmt.Println("\tDone")
break
}
}
return
}
func bounce(server, client *zmq.Socket) {
content := "12345678ABCDEFGH12345678abcdefgh"
// Send message from client to server
rc, err := client.Send(content, zmq.SNDMORE|zmq.DONTWAIT)
if checkErr0(err) {
return
}
if rc != 32 {
checkErr0(errors.New("rc != 32"))
}
rc, err = client.Send(content, zmq.DONTWAIT)
if checkErr0(err) {
return
}
if rc != 32 {
checkErr0(errors.New("rc != 32"))
}
// Receive message at server side
msg, err := server.Recv(0)
if checkErr0(err) {
return
}
// Check that message is still the same
if msg != content {
checkErr0(errors.New(fmt.Sprintf("%q != %q", msg, content)))
}
rcvmore, err := server.GetRcvmore()
if checkErr0(err) {
return
}
if !rcvmore {
checkErr0(errors.New(fmt.Sprint("rcvmore ==", rcvmore)))
return
}
// Receive message at server side
msg, err = server.Recv(0)
if checkErr0(err) {
return
}
// Check that message is still the same
if msg != content {
checkErr0(errors.New(fmt.Sprintf("%q != %q", msg, content)))
}
rcvmore, err = server.GetRcvmore()
if checkErr0(err) {
return
}
if rcvmore {
checkErr0(errors.New(fmt.Sprint("rcvmore == ", rcvmore)))
return
}
// The same, from server back to client
// Send message from server to client
rc, err = server.Send(content, zmq.SNDMORE)
if checkErr0(err) {
return
}
if rc != 32 {
checkErr0(errors.New("rc != 32"))
}
rc, err = server.Send(content, 0)
if checkErr0(err) {
return
}
if rc != 32 {
checkErr0(errors.New("rc != 32"))
}
// Receive message at client side
msg, err = client.Recv(0)
if checkErr0(err) {
return
}
// Check that message is still the same
if msg != content {
checkErr0(errors.New(fmt.Sprintf("%q != %q", msg, content)))
}
rcvmore, err = client.GetRcvmore()
if checkErr0(err) {
return
}
if !rcvmore {
checkErr0(errors.New(fmt.Sprint("rcvmore ==", rcvmore)))
return
}
// Receive message at client side
msg, err = client.Recv(0)
if checkErr0(err) {
return
}
// Check that message is still the same
if msg != content {
checkErr0(errors.New(fmt.Sprintf("%q != %q", msg, content)))
}
rcvmore, err = client.GetRcvmore()
if checkErr0(err) {
return
}
if rcvmore {
checkErr0(errors.New(fmt.Sprint("rcvmore == ", rcvmore)))
return
}
}
