用一了段時間NSQ還是很穩定的。除了穩定，還有一個特別值的說的就是部署非常簡單。總想寫點什麼推薦給大家使用nsq來做一些東西。但是就是因為他太簡單易用，文件也比較簡單易懂。一直不知道要寫啥！！！！！

　　為了容災需要對nsqd多機器部屬，有了Docker後，快速擴還是很方便的。

　　部署完後我會用go和c#寫一些程式碼方便大家學習。

　　準備工作：

　　》兩臺伺服器：192.168.0.49; 192.168.0.105.

　　》需要在兩臺機器上安裝好Docker

　　》兩臺機器上映象的拉取 

docker pull nsqio/nsq

　　我們在105上啟動lookup, nsqd和客戶端都需要連線這個lookup。　　

docker run --name lookupd -p 4160:4160 -p 4161:4161 nsqio/nsq /nsqlookupd

　　在105和49上啟動nsqd， lookup的地址要寫105

docker run --name nsqd -p 4150:4150 -p 4151:4151     nsqio/nsq /nsqd     --broadcast-address=192.168.0.105     --lookupd-tcp-address=192.168.0.105:4160

docker run --name nsqd -p 4150:4150 -p 4151:4151     nsqio/nsq /nsqd     --broadcast-address=192.168.0.49     --lookupd-tcp-address=192.168.0.105:4160

　　到了這一步就可以寫程式碼傳送和接收資訊了。但是還有一個管理系統需要啟動一下。nsqadmin 

docker run --name nsqadmin -p 4171:4171 nsqio/nsq /nsqadmin --lookupd-http-address=192.168.0.105:4161

 　　用瀏覽器看一下管理端：http://192.168.0.105:4171/nodes。找開Nodes標籤裡面有兩個節點。192.168.0.105  和 192.168.0.49。其他的你可以點開看看。

　　我用go語言 簡單寫一個傳送資訊的例子：

func main() {
    config := nsq.NewConfig()
    // 隨便給哪個ip發都可以
    //w1, _ := nsq.NewProducer("192.168.0.105:4150", config)
    w1, _ := nsq.NewProducer("192.168.0.49:4150", config)

    err1 := w1.Ping()
    if err1 != nil {
        log.Fatal("should not be able to ping after Stop()")
        return
    }
    defer w1.Stop()
    topicName := "publishtest"
    msgCount := 2
    for i := 1; i < msgCount; i++ {
        err1 := w1.Publish(topicName, []byte("測試測試publis test case"))
        if err1 != nil {
            log.Fatal("error")
        }
    }
}

　　可以嘗試給49和105都發送一次試試。再看一下我們的管理頁面：

　　publishtest被ip105和49都發送過。但是還沒有channel:

 客戶端golang程式碼

package main

import (
    "fmt"
    "github.com/nsqio/go-nsq"
    "log"
    "os"
    "os/signal"
    "strconv"
    "time"
    "sync"
)

func main() {

    topicName := "publishtest"
    msgCount := 2
    for i := 0; i < msgCount; i++ {
        //time.Sleep(time.Millisecond * 20)
        go readMessage(topicName, i)
    }

    //cleanup := make(chan os.Signal, 1)
    cleanup := make(chan os.Signal)
    signal.Notify(cleanup, os.Interrupt)
    fmt.Println("server is running....")

    quit := make(chan bool)
    go func() {
        
        select {
            case <- cleanup:
                fmt.Println("Received an interrupt , stoping service ...")
                for _, ele := range consumers {
                    ele.StopChan <- 1
                    ele.Stop()
                }
                quit <- true
        }
    }()
    <-quit
    fmt.Println("Shutdown server....")
}

type ConsumerHandle struct {
    q       *nsq.Consumer
    msgGood int
}

var consumers []*nsq.Consumer = make([]*nsq.Consumer, 0)
var mux *sync.Mutex = &sync.Mutex{}

func (h *ConsumerHandle) HandleMessage(message *nsq.Message) error {
    msg := string(message.Body) + "  " + strconv.Itoa(h.msgGood)
    fmt.Println(msg)

    return nil
}

func readMessage(topicName string, msgCount int) {

    defer func() {
        if err := recover(); err != nil {
            fmt.Println("error: ", err)
        }
    }()

    config := nsq.NewConfig()
    config.MaxInFlight = 1000
    config.MaxBackoffDuration = 500 * time.Second

    //q, _ := nsq.NewConsumer(topicName, "ch" + strconv.Itoa(msgCount), config)
    //q, _ := nsq.NewConsumer(topicName, "ch" + strconv.Itoa(msgCount) + "#ephemeral", config)
    q, _ := nsq.NewConsumer(topicName, "ch"+strconv.Itoa(msgCount), config)

    h := &ConsumerHandle{q: q, msgGood: msgCount}
    q.AddHandler(h)

    err := q.ConnectToNSQLookupd("192.168.0.105:4161")
    //err := q.ConnectToNSQDs([]string{"192.168.0.105:4161"})
    //err := q.ConnectToNSQD("192.168.0.49:4150")
    //err := q.ConnectToNSQD("192.168.0.105:4415")
    if err != nil {
        fmt.Println("conect nsqd error")
        log.Println(err)
    }
    mux.Lock()
    consumers = append(consumers, q)
    mux.Unlock()
    <-q.StopChan
    fmt.Println("end....")
}

　　執行一下，會啟動兩個終端：

　　用我們的傳送程式碼傳送資訊，再看我們的客戶端

　　c# 使用的庫為NsqSharp.Core 地址為：

　　簡單客戶端程式碼為：

class Program
    {
        static void Main()
        {
            // Create a new Consumer for each topic/channel
            var consumerCount = 2;
            var listC = new  List<Consumer>();
            for (var i = 0; i < consumerCount; i++)
            {
                var consumer = new Consumer("publishtest", $"channel{i}" );
                consumer.ChangeMaxInFlight(2500);
                consumer.AddHandler(new MessageHandler());
                consumer.ConnectToNsqLookupd("192.168.0.105:4161");
                listC.Add(consumer);
            }


            var exitEvent = new ManualResetEvent(false);

            Console.CancelKeyPress += (sender, eventArgs) => {
                eventArgs.Cancel = true;
                listC.ForEach(x => x.Stop());
                exitEvent.Set();
            };

            exitEvent.WaitOne();
           
            
        }
    }

    public class MessageHandler : IHandler
    {
        /// <summary>Handles a message.</summary>
        public void HandleMessage(IMessage message)
        {
            string msg = Encoding.UTF8.GetString(message.Body);
            Console.WriteLine(msg);
        }

        /// <summary>
        /// Called when a message has exceeded the specified <see cref="Config.MaxAttempts"/>.
        /// </summary>
        /// <param name="message">The failed message.</param>
        public void LogFailedMessage(IMessage message)
        {
            // Log failed messages
        }
    }