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.NET Core 中使用 RabbitMQ 正确方式
首先甩官网:http://www.rabbitmq.com/
然后是.NET Client 链接:http://www.rabbitmq.com/dotnet.html
GitHub 仓库:https://github.com/rabbitmq/rabbitmq-dotnet-client
下面直接进入正文, 一共是两个主题: 消费者怎么写? 生产者怎么写?
消费者
在 dotnet core mvc 中, 消费者肯定不能通过 API 或者其他的东西启动, 理应是跟着程序一起启动的.
所以 …
在 dotnet core 2.0 以上版本, 我们直接用 IHostedService 接口实现.
.NET Core 中基于 IHostedService 实现后台定时任务
Implementing background tasks in .NET Core 2.x webapps or microservices with IHostedService and the BackgroundService class
直接上代码.
// RabbitListener.cs 这个是基类, 只实现注册 RabbitMQ 后到监听消息, 然后每个消费者自己去重写 RouteKey/QueueName/ 消息处理函数 Process
using System;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using RabbitMQ.Client;
using RabbitMQ.Client.Events;
namespace Test.Listener
{
public class RabbitListener : IHostedService
{
private readonly IConnection connection;
private readonly IModel channel;
public RabbitListener(IOptions<AppConfiguration> options)
{
try
{
var factory = new ConnectionFactory()
{
// 这是我这边的配置, 自己改成自己用就好
HostName = options.Value.RabbitHost,
UserName = options.Value.RabbitUserName,
Password = options.Value.RabbitPassword,
Port = options.Value.RabbitPort,
};
this.connection = factory.CreateConnection();
this.channel = connection.CreateModel();
}
catch (Exception ex)
{
Console.WriteLine($”RabbitListener init error,ex:{ex.Message}”);
}
}
public Task StartAsync(CancellationToken cancellationToken)
{
Register();
return Task.CompletedTask;
}
protected string RouteKey;
protected string QueueName;
// 处理消息的方法
public virtual bool Process(string message)
{
throw new NotImplementedException();
}
// 注册消费者监听在这里
public void Register()
{
Console.WriteLine($”RabbitListener register,routeKey:{RouteKey}”);
channel.ExchangeDeclare(exchange: “message”, type: “topic”);
channel.QueueDeclare(queue:QueueName, exclusive: false);
channel.QueueBind(queue: QueueName,
exchange: “message”,
routingKey: RouteKey);
var consumer = new EventingBasicConsumer(channel);
consumer.Received += (model, ea) =>
{
var body = ea.Body;
var message = Encoding.UTF8.GetString(body);
var result = Process(message);
if (result)
{
channel.BasicAck(ea.DeliveryTag, false);
}
};
channel.BasicConsume(queue: QueueName, consumer: consumer);
}
public void DeRegister()
{
this.connection.Close();
}
public Task StopAsync(CancellationToken cancellationToken)
{
this.connection.Close();
return Task.CompletedTask;
}
}
}
// 随便贴一个子类
using System;
using System.Text;
using Microsoft.Extensions.Options;
using Newtonsoft.Json.Linq;
using RabbitMQ.Client;
using RabbitMQ.Client.Events;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Logging;
namespace Test.Listener
{
public class ChapterLister : RabbitListener
{
private readonly ILogger<RabbitListener> _logger;
// 因为 Process 函数是委托回调, 直接将其他 Service 注入的话两者不在一个 scope,
// 这里要调用其他的 Service 实例只能用 IServiceProvider CreateScope 后获取实例对象
private readonly IServiceProvider _services;
public ChapterLister(IServiceProvider services, IOptions<AppConfiguration> options,
ILogger<RabbitListener> logger) : base(options)
{
base.RouteKey = “done.task”;
base.QueueName = “lemonnovelapi.chapter”;
_logger = logger;
_services = services;
}
public override bool Process(string message)
{
var taskMessage = JToken.Parse(message);
if (taskMessage == null)
{
// 返回 false 的时候回直接驳回此消息, 表示处理不了
return false;
}
try
{
using (var scope = _services.CreateScope())
{
var xxxService = scope.ServiceProvider.GetRequiredService<XXXXService>();
return true;
}
}
catch (Exception ex)
{
_logger.LogInformation($”Process fail,error:{ex.Message},stackTrace:{ex.StackTrace},message:{message}”);
_logger.LogError(-1, ex, “Process fail”);
return false;
}
}
}
}
然后, 记住 ….
注入到 Startup.cs 的时候, 使用 AddHostedService
services.AddHostedService<ChapterLister>();
消费者就这样玩了.
生产者咋玩呢?
这个其实更简单.
using System;
using System.Net;
using Newtonsoft.Json.Linq;
using RestSharp;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using RabbitMQ.Client;
using Newtonsoft.Json;
using System.Text;
namespace Test.SDK
{
public class RabbitMQClient
{
private readonly IModel _channel;
private readonly ILogger _logger;
public RabbitMQClient(IOptions<AppConfiguration> options, ILogger<RabbitMQClient> logger)
{
try
{
var factory = new ConnectionFactory()
{
HostName = options.Value.RabbitHost,
UserName = options.Value.RabbitUserName,
Password = options.Value.RabbitPassword,
Port = options.Value.RabbitPort,
};
var connection = factory.CreateConnection();
_channel = connection.CreateModel();
}
catch (Exception ex)
{
logger.LogError(-1, ex, “RabbitMQClient init fail”);
}
_logger = logger;
}
public virtual void PushMessage(string routingKey, object message)
{
_logger.LogInformation($”PushMessage,routingKey:{routingKey}”);
_channel.QueueDeclare(queue: “message”,
durable: false,
exclusive: false,
autoDelete: false,
arguments: null);
string msgJson = JsonConvert.SerializeObject(message);
var body = Encoding.UTF8.GetBytes(msgJson);
_channel.BasicPublish(exchange: “message”,
routingKey: routingKey,
basicProperties: null,
body: body);
}
}
}
切记注入实例的时候用单例模式.
services.AddSingleton<RabbitMQClient, RabbitMQClient>();
全文完 …