高并发场景之RabbitMQ篇

上次我们介绍了在单机、集群下高并发场景可以选择的一些方案，传送门：高并发场景之一般解决方案

但是也发现了一些问题，比如集群下使用ConcurrentQueue或加锁都不能解决问题，后来采用Redis队列也不能完全解决问题，

因为使用Redis要自己实现分布式锁

这次我们来了解一下一个专门处理队列的组件：RabbitMQ，这个东西天生支持分布式队列。

下面我们来用RabbitMQ来实现上一篇的场景

一、新建RabbitMQ.Receive

private static ConnectionFactory factory = new ConnectionFactory 
{ HostName = "192.168.1.109", UserName = "ljr", Password = "root", VirtualHost = "/" };

 1         static void Main(string[] args)
 2         {
 3             using (var connection = factory.CreateConnection())
 4             {
 5                 using (var channel = connection.CreateModel())
 6                 {
 7                     var consumer = new EventingBasicConsumer();
 8                     consumer.Received += (model, ea) =>
 9                     {
10                         var body = ea.Body;
11                         var message = Encoding.UTF8.GetString(body);
12                         Console.WriteLine(" [x] Received {0}", message);
13 
14                         var total = DbHelper.ExecuteScalar("Select Total from ConCurrency where Id = 1", null).ToString();
15                         var value = int.Parse(total) + 1;
16 
17                         DbHelper.ExecuteNonQuery(string.Format("Update ConCurrency Set Total = {0} where Id = 1", value.ToString()), null);
18                     };
19 
20                     channel.QueueDeclare(queue: "queueName", durable: false, exclusive: false, autoDelete: false, arguments: null);
21                     channel.BasicConsume(queue: "queueName", noAck: true, consumer: consumer);
22 
23                     Console.WriteLine(" Press [enter] to exit.");
24                     Console.ReadLine();
25                 }
26             }
27         }

二、新建RabbitMQ.Send　　

 1         static void Main(string[] args)
 2         {
 3             for (int i = 1; i <= 500; i++)
 4             {
 5                 Task.Run(async () =>
 6                 {
 7                     await Produce();
 8                 });
 9 
10                 Console.WriteLine(i);
11             }
12 
13             Console.ReadKey();
14         }
15 
16         public static Task Produce()
17         {
18             return Task.Factory.StartNew(() =>
19             {
20                 using (var connection = factory.CreateConnection())
21                 {
22                     using (var channel = connection.CreateModel())
23                     {
24                         var body = Encoding.UTF8.GetBytes(Guid.NewGuid().ToString());
25                         channel.QueueDeclare(queue: "queueName", durable: false, exclusive: false, autoDelete: false, arguments: null);
26                         channel.BasicPublish(exchange: "", routingKey: "queueName", basicProperties: null, body: body);
27                     }
28                 }
29             });
30         }

这里是模拟500个用户请求，正常的话最后Total就等于500

我们来说试试看，运行程序

2.1、打开接收端

2.2 运行客户端

2.3、可以看到2边几乎是实时的，再去看看数据库

三、我们在集群里执行 

最后数据是1000

 完全没有冲突，好了，就是这样 、。