Golang RABBITMQ Practice (two implementations of simple messaging)

This is a creation in Article, where the information may have evolved or changed.

1: Drive

Originally intended to write a driver, and later found that GitHub above already have, then I directly take off-the-shelf, drive using GITHUB.COM/STREADWAY/AMQP, Direct import can!

2:exchange and queue

In the previous article, we've created VirtualHost, Exchange and queue, so we'll define these constants first.

　　

Const (    "push.msg.q"    Exchange  "t.msg.ex " = "amqp://shi:123@192.168.232.130:5672/test")      

var conn *amqp. Connection
var channel *AMQP. Channel

3: Error Handling

　　

Func Failonerr (Err error, msg string) {if err! = Nil {log. Fatalf ("%s:%s", MSG, err) panic (FMT. Sprintf ("%s:%s", MSG, err)}}

4: Connect MQ

func mqconnect () {    var  err error    = amqp. Dial (mqurl)    "failed to connect TP RABBITMQ")    = Conn. Channel ()    "failed to open a channel")}

5:push

First on the code:

 func push () { if  channel == nil {mqconnect ()} msgcontent:  =  hello world!   "  channel. Publish (Exchange, QueueName,  false ,  , AMQP. publishing{ContentType:   text/plain
       " , Body: []  byte   

In fact, it is very simple to call the Channel function publish method, incoming Exchange name and queue name, the last parameter is the message content, contenttype we set to Text/plain, for the text type, Body is the message content, to pass in a byte array, so that a message is completed push, then we look at receive

6:receive

Code:

func receive () {ifChannel = =Nil {mqconnect ()} msgs, err:= Channel. Consume (QueueName,"",true,false,false,false, nil) failonerr (err,"") Forever:= Make (chanBOOL) go func () {//FMT. Println (*MSGS)         forD: =Range Msgs {s:= Bytestostring (&(d.body)) Count++FMT. Printf ("receve msg is:%s--%d\n", *s, Count)} } () Fmt. Printf ("[*] waiting for messages. To exit Press ctrl+c\n")    <-Forever}

by calling the channel. The consume function returns a Chan-type pipe that accepts a message, and then range this Chan, the received data is []byte, converted to string output

<-Forever This is to control the current thread does not exit

7: Entrance Main

　　

Func Main () {    go func () {        for  {            push () time            . Sleep (1 * Time . Second)        }    } ()    receive ()    FMT. Println ("end")    close ()}

The For loop guarantees that a message is sent to MQ every second, and this place is guaranteed not to block the main thread with a co-process. The receive function cannot use a co-process, or the main thread exits. The close function frees the connection object, but in this case it is not effective because the thread will never quit automatically, only to think that CTRL + C or the program is dead, and the system restarts

8: Execution:

Switch to go file directory execution

Go Run main.go
//Run log Receve msg Is:hello world! --1246
Receve msg Is:hello world! --1247
Receve msg Is:hello world! --1248
Receve msg Is:hello world! --1249
Receve msg Is:hello world! --1250
Receve msg Is:hello world! --1251
Receve msg Is:hello world! --1252
Receve msg Is:hello world! --1253
Receve msg Is:hello world! --1254
Receve msg Is:hello world! --1255
Receve msg Is:hello world! --1256
Receve msg Is:hello world! --1257
Receve msg Is:hello world! --1258
Receve msg Is:hello world! --1259
Receve msg Is:hello world! --1260
Receve msg Is:hello world! --1261
Receve msg Is:hello world! --1262
Receve msg Is:hello world! --1263
Receve msg Is:hello world! --1264
Receve msg Is:hello world! --1265
Receve msg Is:hello world! --1266

9: All code

Package Mainimport ("FMT"    "Log"    "bytes"    " Time"    "GITHUB.COM/STREADWAY/AMQP")varConn *AMQP. ConnectionvarChannel *AMQP. ChannelvarCount =0Const(QueueName="push.msg.q"Exchange="T.msg.ex"Mqurl="amqp://shi:123@192.168.232.130:5672/test") Func main () {go func () { for{push () time. Sleep (1*Time . Second)}} () receive () FMT. Println ("End") Close ()}func Failonerr (err error, MSGstring) {    ifErr! =Nil {log. Fatalf ("%s:%s", MSG, err) panic (FMT. Sprintf ("%s:%s", MSG, err)) }}func Mqconnect () {varERR Error conn, err=AMQP. Dial (Mqurl) Failonerr (err,"failed to connect TP RABBITMQ") channel, err=Conn. Channel () Failonerr (err,"failed to open a channel")}func Close () {channel. Close () Conn. Close ()}//Connecting RABBITMQ serverfunc push () {ifChannel = =Nil {mqconnect ()} msgcontent:="Hello world!"Channel. Publish (Exchange, QueueName,false,false, AMQP. publishing{ContentType:"Text/plain", Body: []byte(Msgcontent),})} Func receive () {ifChannel = =Nil {mqconnect ()} msgs, err:= Channel. Consume (QueueName,"",true,false,false,false, nil) failonerr (err,"") Forever:= Make (chanBOOL) go func () {//FMT. Println (*MSGS)         forD: =Range Msgs {s:= Bytestostring (&(d.body)) Count++FMT. Printf ("receve msg is:%s--%d\n", *s, Count)} } () Fmt. Printf ("[*] waiting for messages. To exit Press ctrl+c\n")    <-Forever}func bytestostring (b*[]byte) *string{s:= bytes. Newbuffer (*b) R:=s.string ()return&R}