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/*
* Copyright (c) 2013 IBM Corp.
*
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* Seth Hoenig
* Allan Stockdill-Mander
* Mike Robertson
*/
/*----------------------------------------------------------------------
This sample is designed to demonstrate the ability to set individual
callbacks on a per-subscription basis. There are three handlers in use:
brokerLoadHandler - $SYS/broker/load/#
brokerConnectionHandler - $SYS/broker/connection/#
brokerClientHandler - $SYS/broker/clients/#
The client will receive 100 messages total from those subscriptions,
and then print the total number of messages received from each.
It may take a few moments for the sample to complete running, as it
must wait for messages to be published.
-----------------------------------------------------------------------*/
package main
import (
"fmt"
"os"
MQTT "github.com/eclipse/paho.mqtt.golang"
)
var brokerLoad = make(chan bool)
var brokerConnection = make(chan bool)
var brokerClients = make(chan bool)
func brokerLoadHandler(client MQTT.Client, msg MQTT.Message) {
brokerLoad <- true
fmt.Printf("BrokerLoadHandler ")
fmt.Printf("[%s] ", msg.Topic())
fmt.Printf("%s\n", msg.Payload())
}
func brokerConnectionHandler(client MQTT.Client, msg MQTT.Message) {
brokerConnection <- true
fmt.Printf("BrokerConnectionHandler ")
fmt.Printf("[%s] ", msg.Topic())
fmt.Printf("%s\n", msg.Payload())
}
func brokerClientsHandler(client MQTT.Client, msg MQTT.Message) {
brokerClients <- true
fmt.Printf("BrokerClientsHandler ")
fmt.Printf("[%s] ", msg.Topic())
fmt.Printf("%s\n", msg.Payload())
}
func main() {
opts := MQTT.NewClientOptions().AddBroker("tcp://iot.eclipse.org:1883").SetClientID("router-sample")
opts.SetCleanSession(true)
c := MQTT.NewClient(opts)
if token := c.Connect(); token.Wait() && token.Error() != nil {
panic(token.Error())
}
if token := c.Subscribe("$SYS/broker/load/#", 0, brokerLoadHandler); token.Wait() && token.Error() != nil {
fmt.Println(token.Error())
os.Exit(1)
}
if token := c.Subscribe("$SYS/broker/connection/#", 0, brokerConnectionHandler); token.Wait() && token.Error() != nil {
fmt.Println(token.Error())
os.Exit(1)
}
if token := c.Subscribe("$SYS/broker/clients/#", 0, brokerClientsHandler); token.Wait() && token.Error() != nil {
fmt.Println(token.Error())
os.Exit(1)
}
loadCount := 0
connectionCount := 0
clientsCount := 0
for i := 0; i < 100; i++ {
select {
case <-brokerLoad:
loadCount++
case <-brokerConnection:
connectionCount++
case <-brokerClients:
clientsCount++
}
}
fmt.Printf("Received %3d Broker Load messages\n", loadCount)
fmt.Printf("Received %3d Broker Connection messages\n", connectionCount)
fmt.Printf("Received %3d Broker Clients messages\n", clientsCount)
c.Disconnect(250)
}
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