.NET中消息队列RabbitMQ的使用
概述
MQ全称为Message Queue, 消息队列（MQ）是一种应用程序对应用程序的通信方法。RabbitMQ是一个在AMQP基础上完整的，可复用的企业消息系统。他遵循Mozilla Public License开源协议。AMQP(高级消息队列协议) 是一个异步消息传递所使用的应用层协议规范，作为线路层协议，而不是API（例如JMS），AMQP 客户端能够无视消息的来源任意发送和接受信息。AMQP的原始用途只是为金融界提供一个可以彼此协作的消息协议，而现在的目标则是为通用消息队列架构提供通用构建工具。因此，面向消息的中间件 （MOM）系统，例如发布/订阅队列，没有作为基本元素实现。AMQP当中有四个概念非常重要（一个虚拟主机持有一组交换机、队列和绑定）：
virtual host，虚拟主机exchange，交换机queue，队列binding，绑定
Window下安装RabbbitMQ
文件下载安装
Rabbit MQ 是建立在强大的Erlang OTP平台上，因此安装Rabbit MQ的前提是安装Erlang。通过下面两个连接下载安装3.2.3 版本：
- 下载并安装 Erlang OTP For Windows (vR16B03)
- 运行安装 Rabbit MQ Server Windows Installer (v3.2.3)
默认安装的Rabbit MQ 监听端口是5672。先安装Erlang OTP后安装RabbitMQ，安装方式默认即可，RabbitMQ可以勾选安装后台服务、服务启动和停止等操作。
激活Rabbit MQ's Management Plugin
使用Rabbit MQ 管理插件，可以更好的可视化方式查看Rabbit MQ 服务器实例的状态，打开CMD命令，cd到安装目录（..\rabbitmq_server-3.2.3\sbin）下，输入下面的命令激活：
rabbitmq-plugins enable rabbitmq_management
要重启服务才能生效，可以执行
net stop RabbitMQ && net start RabbitMQ
输入网址，打开监控页面： http://localhost:15672 (默认账号和密码：guest 和guest)
配置RabbitMQ用户权限
RabbitMQ是存在用户权限的，默认是guest 密码也是guest，隶属于Administrator管理员下。现需要配置新用户和权限，继续打开CMD命令，cd到安装目录sbin下：
用户操作指令：
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::查询服务状态rabbitmqctl status::列举虚拟主机列表rabbitmqctl list_vhosts::列举用户列表rabbitmqctl list_users:: 添加用户和密码rabbitmqctl add_user hao abc123:: 设置权限 rabbitmqctl set_permissions yy ".*" ".*" ".*":: 分配用户组rabbitmqctl set_user_tags yy administrator:: 删除guest用户rabbitmqctl delete_user guest::修改用户密码rabbitmqctl change_password {username} {newpassowrd} |
像ADO.Net的五大对象也是，操作数据库先进行连接connection,然后使用command过滤出要选择的数据，使用DataReader或DataSet、DataAdapter,在RabbitMQ的使用当中也有基本固定的步骤。
一、生产者
1.创建连接connection:不管是生产者还是消费者都需要先于RabbitMQ服务器连接，才能进行数据交换
2.创建通道 Channel:生产者、消费者的消息传递是在通道下传递的
3.声明交换器、队列
4.交换器与队列进行绑定
5.通过交换器BasicPublish数据到队列
二、消费者
1.创建连接 :和生产者一样
2.创建通道:和生产者一样
3.声明交换器、队列
4.交换器与队列进行绑定
5.通过BasicGet方法获取队列中的数据
上面一、二是大致的基本步骤，按照大致的步骤来基本不会出现大的问题，其实生产者和消费者的前4个步骤基本一样，主要是第5个步骤，一个是生产BasicPublish发布，一个是获取Get。
三、出现的错误
在ConnectionFactory创建连接对象时出现上面提到的bug:None of the specified endpoints were reachable.
四、demo
1.首先在生产者端和消费者端引入RabbitMQ
2.生产者端
using RabbitMQ.Client;
using System;
using System.Text;
namespace RabbitMQProduct
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine("Welcome to RabbitMQ Product!");
DirectExchangeSendMsg();
// TopicExchangeSendMsg();
Console.WriteLine("按任意值，退出程序");
Console.ReadKey();
}
/// <summary>
/// 连接配置
/// </summary>
private static readonly ConnectionFactory rabbitMqFactory = new ConnectionFactory()
{
UserName = "howdyadmin",
Password = "123456",
Port = 5672,
VirtualHost = "howdyVirtualHost"
};
/// <summary>
/// 路由名称
/// </summary>
const string ExchangeName = "howdy.exchange";
//队列名称
const string QueueName = "howdy.queue";
/// <summary>
/// 路由名称
/// </summary>
const string TopExchangeName = "topic.howdy.exchange";
//队列名称
const string TopQueueName = "topic.howdy.queue";
/// <summary>
/// 单点精确路由模式
/// </summary>
public static void DirectExchangeSendMsg()
{
using (IConnection conn = rabbitMqFactory.CreateConnection())
{
using (IModel channel = conn.CreateModel())
{
channel.ExchangeDeclare(ExchangeName, ExchangeType.Direct, durable: true, autoDelete: false, arguments: null);
channel.QueueDeclare(QueueName, durable: true, autoDelete: false, exclusive: false, arguments: null);
channel.QueueBind(QueueName, ExchangeName, routingKey: QueueName);
var props = channel.CreateBasicProperties();
props.Persistent = true;
string vadata = Console.ReadLine();
while (vadata != "exit")
{
var msgBody = Encoding.UTF8.GetBytes(vadata);
channel.BasicPublish(exchange: ExchangeName, routingKey: QueueName, basicProperties: props, body: msgBody);
Console.WriteLine(string.Format("***发送时间:{0}，发送完成，输入exit退出消息发送",
DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss")));
vadata = Console.ReadLine();
}
}
}
}
/// <summary>
/// topic 模糊匹配模式，符号“#”匹配一个或多个词，符号“*”匹配不多不少一个词。因此“log.#”能够匹配到“log.info.oa”，但是“log.*” 只会匹配到“log.error”
/// </summary>
public static void TopicExchangeSendMsg()
{
using (IConnection conn = rabbitMqFactory.CreateConnection())
{
using (IModel channel = conn.CreateModel())
{
channel.ExchangeDeclare(TopExchangeName,ExchangeType.Topic, durable: false, autoDelete: false, arguments: null);
channel.QueueDeclare(TopQueueName, durable: false, autoDelete: false, exclusive: false, arguments: null);
channel.QueueBind(TopQueueName, TopExchangeName, routingKey: TopQueueName);
//var props = channel.CreateBasicProperties();
//props.Persistent = true;
string vadata = Console.ReadLine();
while (vadata != "exit")
{
var msgBody = Encoding.UTF8.GetBytes(vadata);
channel.BasicPublish(exchange: TopExchangeName, routingKey: TopQueueName, basicProperties: null, body: msgBody);
Console.WriteLine(string.Format("***发送时间:{0}，发送完成，输入exit退出消息发送", DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss")));
vadata = Console.ReadLine();
}
}
}
}
}
}
上面的代码分别创建了两个路由和两个队列，一种是DirectExchange，一种是TopicExchange，验证时需要生产者和消费者使用同一种的ExChange。
3.消费者端
using RabbitMQ.Client;
using RabbitMQ.Client.Events;
using System;
using System.Text;
namespace RabbitMQConsumer
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine("Welcome to RabbitMQ Consumer!");
//DirectAcceptExchange();
//DirectAcceptExchangeEvent();
DirectAcceptExchangeTask();
//TopicAcceptExchange();
Console.WriteLine("按任意值，退出程序");
Console.ReadKey();
}
/// <summary>
/// 连接配置
/// </summary>
private static readonly ConnectionFactory rabbitMqFactory = new ConnectionFactory()
{
HostName = "127.0.0.1",
UserName = "howdyadmin",
Password = "123456",
Port = 5672,
VirtualHost = "howdyVirtualHost"
};
/// <summary>
/// 路由名称
/// </summary>
const string ExchangeName = "howdy.exchange";
//队列名称
const string QueueName = "howdy.queue";
/// <summary>
/// 路由名称
/// </summary>
const string TopExchangeName = "topic.howdy.exchange";
//队列名称
const string TopQueueName = "topic.howdy.queue";
/// <summary>
/// 基于时间轮询的，每隔一段时间获取一次
/// </summary>
public static void DirectAcceptExchange()
{
using (IConnection conn = rabbitMqFactory.CreateConnection())
{
using (IModel channel = conn.CreateModel())
{
channel.ExchangeDeclare(ExchangeName, ExchangeType.Direct, durable: true, autoDelete: false, arguments: null);
channel.QueueDeclare(QueueName, durable: true, autoDelete: false, exclusive: false, arguments: null);
channel.QueueBind(QueueName, ExchangeName, routingKey: QueueName);
while (true)
{
BasicGetResult msgResponse = channel.BasicGet(QueueName, true);
if (msgResponse != null)
{
var msgBody = Encoding.UTF8.GetString(msgResponse.Body);
Console.WriteLine(string.Format("***接收时间:{0}，消息内容：{1}", DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss"), msgBody));
}
System.Threading.Thread.Sleep(TimeSpan.FromSeconds(1));
}
}
}
}
/// <summary>
/// 基于事件的，当消息到达时触发事件，获取数据
/// </summary>
public static void DirectAcceptExchangeEvent()
{
using (IConnection conn = rabbitMqFactory.CreateConnection())
{
using (IModel channel = conn.CreateModel())
{
//channel.ExchangeDeclare(ExchangeName, "direct", durable: true, autoDelete: false, arguments: null);
channel.QueueDeclare(QueueName, durable: true, autoDelete: false, exclusive: false, arguments: null);
//channel.QueueBind(QueueName, ExchangeName, routingKey: QueueName);
var consumer = new EventingBasicConsumer(channel);
consumer.Received += (model, ea) =>
{
var msgBody = Encoding.UTF8.GetString(ea.Body);
Console.WriteLine(string.Format("***接收时间:{0}，消息内容：{1}", DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss"), msgBody));
};
channel.BasicConsume(QueueName, true, consumer: consumer);
Console.WriteLine("按任意值，退出程序");
Console.ReadKey();
}
}
}
/// <summary>
/// 基于事件的，当消息到达时触发事件，获取数据
/// </summary>
public static void DirectAcceptExchangeTask()
{
using (IConnection conn = rabbitMqFactory.CreateConnection())
{
using (IModel channel = conn.CreateModel())
{
//channel.ExchangeDeclare(ExchangeName, "direct", durable: true, autoDelete: false, arguments: null);
channel.QueueDeclare(QueueName, durable: true, autoDelete: false, exclusive: false, arguments: null);
channel.BasicQos(prefetchSize: 0, prefetchCount: 1, global: false);//告诉broker同一时间只处理一个消息
//channel.QueueBind(QueueName, ExchangeName, routingKey: QueueName);
var consumer = new EventingBasicConsumer(channel);
consumer.Received += (model, ea) =>
{
var msgBody = Encoding.UTF8.GetString(ea.Body);
Console.WriteLine(string.Format("***接收时间:{0}，消息内容：{1}", DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss"), msgBody));
int dots = msgBody.Split('.').Length - 1;
System.Threading.Thread.Sleep(dots * 1000);
//处理完成，告诉Broker可以服务端可以删除消息，分配新的消息过来
channel.BasicAck(deliveryTag: ea.DeliveryTag, multiple: false);
};
//noAck设置false,告诉broker，发送消息之后，消息暂时不要删除，等消费者处理完成再说
channel.BasicConsume(QueueName, false, consumer: consumer);
Console.WriteLine("按任意值，退出程序");
Console.ReadKey();
}
}
}
/// <summary>
/// topic 模糊匹配模式，符号“#”匹配一个或多个词，符号“*”匹配不多不少一个词。因此“log.#”能够匹配到“log.info.oa”，但是“log.*” 只会匹配到“log.error”
/// </summary>
public static void TopicAcceptExchange()
{
using (IConnection conn = rabbitMqFactory.CreateConnection())
{
using (IModel channel = conn.CreateModel())
{
channel.ExchangeDeclare(TopExchangeName, ExchangeType.Topic, durable: false, autoDelete: false, arguments: null);
channel.QueueDeclare(TopQueueName, durable: false, autoDelete: false, exclusive: false, arguments: null);
channel.BasicQos(prefetchSize: 0, prefetchCount: 1, global: false);
channel.QueueBind(TopQueueName, TopExchangeName, routingKey: TopQueueName);
var consumer = new EventingBasicConsumer(channel);
consumer.Received += (model, ea) =>
{
var msgBody = Encoding.UTF8.GetString(ea.Body);
Console.WriteLine(string.Format("***接收时间:{0}，消息内容：{1}", DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss"), msgBody));
int dots = msgBody.Split('.').Length - 1;
System.Threading.Thread.Sleep(dots * 1000);
Console.WriteLine(" [x] Done");
channel.BasicAck(deliveryTag: ea.DeliveryTag, multiple: false);
};
channel.BasicConsume(TopQueueName, false, consumer: consumer);
Console.WriteLine("按任意值，退出程序");
Console.ReadKey();
}
}
}
}
}
消费者端也是两个路由两个队列，在实现DirectExchange时使用了三种方式，DirectAcceptExchange是基于时间轮询的，每隔一段时间获取一次，DirectAcceptExchangeEvent、DirectAcceptExchangeTask是基于事件的，当消息到达时触发事件，获取数据。
4.实验截图
参考原文地址(感谢分享)：
https://www.cnblogs.com/personblog/p/10681741.html
https://www.cnblogs.com/5ishare/p/6784149.html
http://www.cnblogs.com/xibei666/p/5931267.html#3680686
