// Example destination
func Dest() string {
d := senv.Dest()
if os.Getenv("STOMP_ARTEMIS") == "" {
return d
}
pref := "jms.queue"
if strings.Index(d, "topic") >= 0 {
pref = "jms.topic"
}
return pref + strings.Replace(d, "/", ".", -1)
}
// Connect to a STOMP broker, receive some messages, ACK them, and disconnect.
func main() {
st := time.Now()
// Standard example connect sequence
n, conn, e := sngecomm.CommonConnect(exampid, tag, ll)
if e != nil {
ll.Fatalf("%stag:%s connsess:%s main_on_connect error:%v",
exampid, tag, sngecomm.Lcs,
e.Error()) // Handle this ......
}
pbc := sngecomm.Pbc() // Print byte count
// *NOTE* your application functionaltiy goes here!
// With Stomp, you must SUBSCRIBE to a destination in order to receive.
// Subscribe returns a channel of MessageData struct.
// Here we use a common utility routine to handle the differing subscribe
// requirements of each protocol level.
d := senv.Dest()
id := stompngo.Uuid()
sc := sngecomm.HandleSubscribe(conn, d, id, "client")
ll.Printf("%stag:%s connsess:%s main_subscribe_complete\n",
exampid, tag, conn.Session())
// Read data from the returned channel
var md stompngo.MessageData
for i := 1; i <= senv.Nmsgs(); i++ {
select {
case md = <-sc:
case md = <-conn.MessageData:
// Frames RECEIPT or ERROR not expected here
ll.Fatalf("%stag:%s connsess:%s main_channel_frame error:%v",
exampid, tag, conn.Session(),
e.Error()) // Handle this ......
}
ll.Printf("%stag:%s connsess:%s main_channel_read_complete\n",
exampid, tag, conn.Session())
// MessageData has two components:
// a) a Message struct
// b) an Error value. Check the error value as usual
if md.Error != nil {
ll.Fatalf("%stag:%s connsess:%s main_channel_read error:%v",
exampid, tag, conn.Session(),
e.Error()) // Handle this ......
}
//
ll.Printf("%stag:%s connsess:%s frame_type:%v\n",
exampid, tag, conn.Session(),
md.Message.Command)
if md.Message.Command != stompngo.MESSAGE {
ll.Fatalf("%stag:%s connsess:%s bad_frame frame:%v",
exampid, tag, conn.Session(),
md.Message.Command) // Handle this ......
}
wh := md.Message.Headers
for j := 0; j < len(wh)-1; j += 2 {
ll.Printf("%stag:%s connsess:%s header:%s:%s\n",
exampid, tag, conn.Session(),
wh[j], wh[j+1])
}
if pbc > 0 {
maxlen := pbc
if len(md.Message.Body) < maxlen {
maxlen = len(md.Message.Body)
}
ss := string(md.Message.Body[0:maxlen])
ll.Printf("%stag:%s connsess:%s message_payload body:%s\n",
exampid, tag, conn.Session(),
ss)
}
// ACK the message just received.
// Agiain we use a utility routine to handle the different requirements
// of the protocol versions.
sngecomm.HandleAck(conn, md.Message.Headers, id)
ll.Printf("%stag:%s connsess:%s ack_complete\n",
exampid, tag, conn.Session())
}
// It is polite to unsubscribe, although unnecessary if a disconnect follows.
// Again we use a utility routine to handle the different protocol level
// requirements.
sngecomm.HandleUnsubscribe(conn, d, id)
ll.Printf("%stag:%s connsess:%s stomp_unsubscribe_complete\n",
exampid, tag, conn.Session())
// Standard example disconnect sequence
e = sngecomm.CommonDisconnect(n, conn, exampid, tag, ll)
if e != nil {
ll.Fatalf("%stag:%s connsess:%s disconnect error:%v",
exampid, tag, conn.Session(),
e.Error()) // Handle this ......
}
ll.Printf("%stag:%s connsess:%s main_elapsed:%v\n",
exampid, tag, conn.Session(),
time.Now().Sub(st))
}
func runNextQueue(qn int, conn *stompngo.Connection) {
qns := fmt.Sprintf("%d", qn) // string number of the queue
conn.SetLogger(ll) // stompngo logging
pbc := sngecomm.Pbc() // Print byte count
d := senv.Dest() + qns // Destination
id := stompngo.Uuid() // A unique name/id
nmsgs := qn // int number of messages to get, same as queue number
am := sngecomm.AckMode() // ACK mode to use on SUBSCRIBE
nfa := true // Need "final" ACK (possiby reset below)
wh := stompngo.Headers{} // Starting SUBSCRIBE headers
// Sanity check ACK mode
if conn.Protocol() == stompngo.SPL_10 &&
am == stompngo.AckModeClientIndividual {
ll.Fatalf("%stag:%s connsess:%s invalid_ack_mode am:%v proto:%v\n",
exampid, tag, session,
am, conn.Protocol()) //
}
// Do not do final ACK if running ACKs are issued
if am == stompngo.AckModeClientIndividual ||
am == stompngo.AckModeAuto {
nfa = false
}
// Show run parameters
ll.Printf("%stag:%s connsess:%s run_parms\n\tqns:%v\n\tpbc:%v\n\td:%v\n\tid:%v\n\tnmsgs:%v\n\tam:%v\n\tnfa:%v\n\twh:%v\n",
exampid, tag, session,
qns, pbc, d, id, nmsgs, am, nfa, wh)
// Run SUBSCRIBE
sc := doSubscribe(conn, d, id, am, wh)
ll.Printf("%stag:%s connsess:%s stomp_subscribe_complete\n",
exampid, tag, session)
var md stompngo.MessageData // Message data from basic read
var lmd stompngo.MessageData // Possible save (copy) of received data
mc := 1 // Initial message number
// Loop for the requested number of messages
GetLoop:
for {
ll.Printf("%stag:%s connsess:%s start_of_read_loop mc:%v nmsgs:%v\n",
exampid, tag, session, mc, nmsgs)
mcs := fmt.Sprintf("%d", mc) // string number message count
// Get something from the stompngo read routine
select {
case md = <-sc:
case md = <-conn.MessageData:
//
if md.Message.Command == stompngo.RECEIPT {
ll.Printf("%stag:%s connsess:%s have_receipt md:%v\n",
exampid, tag, session,
md)
continue GetLoop
}
ll.Fatalf("%stag:%s connsess:%s ERROR_frame hdrs:%v body:%v\n",
exampid, tag, session,
md.Message.Headers, string(md.Message.Body)) // Handle this ......
}
// Save message data for possible use in the final ACK
if mc == nmsgs && nfa {
lmd = md // Save last message
}
// Basic loop logging
ll.Printf("%stag:%s connsess:%s channel_read_complete qn:%d mc:%d\n",
exampid, tag, session,
qn, mc)
ll.Printf("%stag:%s connsess:%s message_number:%v\n",
exampid, tag, session,
mc)
// Check if reader returned any error
if md.Error != nil {
ll.Fatalf("%stag:%s connsess:%s error_read error:%v",
exampid, tag, session,
md.Error) // Handle this ......
}
// Show frame type
ll.Printf("%stag:%s connsess:%s frame_type cmd:%s\n",
exampid, tag, session,
md.Message.Command)
// Pure sanity check: this should *never* happen based on logic
// above.
if md.Message.Command != stompngo.MESSAGE {
ll.Fatalf("%stag:%s connsess:%s error_frame_type md:%v",
exampid, tag, session,
md) // Handle this ......
}
// Show Message Headers
wh := md.Message.Headers
for j := 0; j < len(wh)-1; j += 2 {
ll.Printf("%stag:%s connsess:%s Header:%s:%s\n",
exampid, tag, session,
wh[j], wh[j+1])
}
// Show (part of) Message Body
if pbc > 0 {
maxlen := pbc
if len(md.Message.Body) < maxlen {
maxlen = len(md.Message.Body)
}
ss := string(md.Message.Body[0:maxlen])
ll.Printf("%stag:%s connsess:%s payload body:%s\n",
exampid, tag, session,
ss)
}
// Sanity check this message payload
wm := wlp + mcs // The left part plus the (string) meassage number]
bm := string(md.Message.Body)
if bm != wm {
ll.Fatalf("%stag:%s connsess:%s error_message_payload\n\tGot %s\n\tWant%s\n",
exampid, tag, session,
bm, wm) // Handle this ......
} else {
ll.Printf("%stag:%s connsess:%s matched_body_string\n%s\n%s\n",
exampid, tag, session,
bm, wm) // Handle this ......)
}
// Run individual ACK if required
if am == stompngo.AckModeClientIndividual {
wh := md.Message.Headers // Copy Headers
if ar { // ACK receipt wanted
wh = wh.Add(stompngo.HK_RECEIPT, "rwanted-"+mcs)
}
sngecomm.HandleAck(conn, wh, id)
ll.Printf("%stag:%s connsess:%s individual_ack_complete mc:%v headers:%v\n",
exampid, tag, session,
mc, md.Message.Headers)
}
// Check for end of loop condition
if mc == nmsgs {
break
}
// Increment loop/message counter
mc++
}
qc := make(chan bool)
go drainSub(session, sc, qc, qn)
dd := false
// Issue the final ACK if needed
if nfa {
wh := lmd.Message.Headers // Copy Headers
if ar { // ACK receipt wanted
wh = wh.Add(stompngo.HK_RECEIPT, "rwanted-fin")
}
sngecomm.HandleAck(conn, wh, id)
ll.Printf("%stag:%s connsess:%s final_ack_complete\n",
exampid, tag, session)
if ar {
ll.Printf("%stag:%s connsess:%s ack_receive_wait_for_drain qn:%d\n",
exampid, tag, session,
qn)
<-qc // Wait for drainSub
ll.Printf("%stag:%s connsess:%s ack_receive_drain_complete qn:%d\n",
exampid, tag, session,
qn)
dd = true
getReceipt(conn)
}
}
if !dd {
ll.Printf("%stag:%s connsess:%s message_loop_wait_for_drain qn:%d\n",
exampid, tag, session,
qn)
<-qc
ll.Printf("%stag:%s connsess:%s message_loop_drain_complete qn:%d\n",
exampid, tag, session,
qn)
}
// Unsubscribe (may be skipped if requested)
if unsub {
sngecomm.HandleUnsubscribe(conn, d, id)
ll.Printf("%stag:%s connsess:%s stomp_unsubscribe_complete\n",
exampid, tag, session)
} else {
ll.Printf("%stag:%s connsess:%s skipping_unsubscribe\n",
exampid, tag, session)
}
}