jinterop/activemq/gorecv/gorecv.go

   1 //
   2 // Copyright © 2011-2018 Guy M. Allard
   3 //
   4 // Licensed under the Apache License, Version 2.0 (the "License");
   5 // you may not use this file except in compliance with the License.
   6 // You may obtain a copy of the License at
   7 //
   8 //     http://www.apache.org/licenses/LICENSE-2.0
   9 //
  10 // Unless required by applicable law or agreed to in writing, software
  11 // distributed under the License is distributed on an "AS IS" BASIS,
  12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13 // See the License for the specific language governing permissions and
  14 // limitations under the License.
  15 //
  16
  17 /*
  18 A message receiver, to demonstrate JMS interoperability.
  19 */
  20 package main
  21
  22 import (
  23         "log"
  24         "os"
  25         "time"
  26         //
  27         "github.com/gmallard/stompngo"
  28         // sngecomm methods are used specifically for these example clients.
  29         "github.com/gmallard/stompngo_examples/sngecomm"
  30 )
  31
  32 var (
  33         exampid = "gorecv: "
  34         ll      = log.New(os.Stdout, "GOJRCV ", log.Ldate|log.Lmicroseconds|log.Lshortfile)
  35         nmsgs   = 1
  36         tag     = "jintamqgr"
  37 )
  38
  39 // Connect to a STOMP broker, receive some messages and disconnect.
  40 func main() {
  41
  42         st := time.Now()
  43
  44         // Standard example connect sequence
  45         // Use AMQ port here
  46         n, conn, e := sngecomm.CommonConnect(exampid, tag, ll)
  47         if e != nil {
  48                 ll.Fatalf("%stag:%s connsess:%s main_on_connect error:%v",
  49                         exampid, tag, sngecomm.Lcs,
  50                         e.Error()) // Handle this ......
  51         }
  52
  53         pbc := sngecomm.Pbc() // Print byte count
  54
  55         // Setup Headers ...
  56         id := stompngo.Uuid() // Use package convenience function for unique ID
  57         d := "/queue/allards.queue"
  58         sc := sngecomm.HandleSubscribe(conn, d, id, "auto")
  59         ll.Printf("%stag:%s connsess:%s stomp_subscribe_complete\n",
  60                 exampid, tag, conn.Session())
  61
  62         //
  63         var md stompngo.MessageData
  64         // Read data from the returned channel
  65         for i := 1; i <= nmsgs; i++ {
  66                 select {
  67                 case md = <-sc:
  68                 case md = <-conn.MessageData:
  69                         // Frames RECEIPT or ERROR not expected here
  70                         ll.Fatalf("%stag:%s connsess:%s bad_frame error:%v",
  71                                 exampid, tag, conn.Session(),
  72                                 e.Error()) // Handle this ......
  73                 }
  74                 ll.Printf("%stag:%s connsess:%s channel_read_complete\n",
  75                         exampid, tag, conn.Session())
  76                 // MessageData has two components:
  77                 // a) a Message struct
  78                 // b) an Error value.  Check the error value as usual
  79                 if md.Error != nil {
  80                         ll.Fatalf("%stag:%s connsess:%s error_read error:%v",
  81                                 exampid, tag, conn.Session(),
  82                                 e.Error()) // Handle this ......
  83                 }
  84                 ll.Printf("%stag:%s connsess:%s frame_type cmd:%s\n",
  85                         exampid, tag, conn.Session(),
  86                         md.Message.Command)
  87
  88                 if md.Message.Command != stompngo.MESSAGE {
  89                         ll.Fatalf("%stag:%s connsess:%s error_frame_type error:%v",
  90                                 exampid, tag, conn.Session(),
  91                                 e.Error()) // Handle this ......
  92                 }
  93                 wh := md.Message.Headers
  94                 for j := 0; j < len(wh)-1; j += 2 {
  95                         ll.Printf("%stag:%s connsess:%s Header:%s:%s\n",
  96                                 exampid, tag, conn.Session(),
  97                                 wh[j], wh[j+1])
  98                 }
  99                 if pbc > 0 {
 100                         maxlen := pbc
 101                         if len(md.Message.Body) < maxlen {
 102                                 maxlen = len(md.Message.Body)
 103                         }
 104                         ss := string(md.Message.Body[0:maxlen])
 105                         ll.Printf("%stag:%s connsess:%s payload body:%s\n",
 106                                 exampid, tag, conn.Session(),
 107                                 ss)
 108                 }
 109         }
 110
 111         //
 112         sngecomm.HandleUnsubscribe(conn, d, id)
 113         ll.Printf("%stag:%s connsess:%s unsubscribe_complete\n",
 114                 exampid, tag, conn.Session())
 115
 116         // Standard example disconnect sequence
 117         e = sngecomm.CommonDisconnect(n, conn, exampid, tag, ll)
 118         if e != nil {
 119                 ll.Fatalf("%stag:%s connsess:%s main_disconnect error:%v",
 120                         exampid, tag, conn.Session(),
 121                         e.Error()) // Handle this ......
 122         }
 123
 124         ll.Printf("%stag:%s connsess:%s main_elapsed:%v\n",
 125                 exampid, tag, conn.Session(),
 126                 time.Now().Sub(st))
 127
 128 }