.Net 6 下WorkerService+RabbitMq实现消息的异步发布订阅
近期项目里有需要用到RabbitMq实现一些业务，学习整理之后在此记录一下，如有问题或者不对的地方，欢迎留言指正。
一、首先创建连接工厂
public class RabbitMQProvider
{
private readonly string _ipAddress;
private readonly int? _port;
private readonly string _username;
private readonly string _password;
public RabbitMQProvider()
{
_ipAddress = ConfigurationHelper.GetKey("RabbitMQIPAddress") ?? throw new ArgumentException("IP地址未配置！");
_username = ConfigurationHelper.GetKey("RabbitMQUserName") ?? throw new ArgumentException("用户名不能为空");
_password = ConfigurationHelper.GetKey("RabbitMQPassword") ?? throw new ArgumentException("密码不能为空");
var timeApan = new TimeSpan(0, 5, 0);
if (ConnectionFactory == null)
{
ConnectionFactory = new ConnectionFactory//创建连接工厂对象
{
HostName = _ipAddress,//IP地址
UserName = _username,//用户账号
Password = _password,//用户密码
//启用自动连接恢复
AutomaticRecoveryEnabled = true,
//VirtualHost = "/mqtest",//RabbitMQ中要请求的VirtualHost名称
ContinuationTimeout = timeApan,
HandshakeContinuationTimeout = timeApan,
RequestedConnectionTimeout = timeApan,
SocketReadTimeout = timeApan,
SocketWriteTimeout = timeApan,
//启用异步消费
DispatchConsumersAsync = true,
//RequestedChannelMax = 5000
};
}
}
public ConnectionFactory ConnectionFactory { get; }
private static IConnection connection;
///
/// 获取RabbitMQ连接对象方法（创建与RabbitMQ的连接）
///
/// 二、消息发布
1、获取连接、交换机和队列
public class RabbitMQPublisher : IPublisher
{
static int x_message_ttl;
static RabbitMQPublisher()
{
int.TryParse(ConfigurationHelper.GetKey("RabbitMQ_x-message-ttl"), out x_message_ttl);
x_message_ttl = x_message_ttl * 60 * 1000;
}
#region
private readonly RabbitMQProvider _provider;
private IConnection _connection;
public RabbitMQPublisher(RabbitMQProvider provider)
{
try
{
_provider = provider;
//if (_connection == null || !_connection.IsOpen)
//{
// _connection = _provider.ConnectionFactory.CreateConnection();
//}
_connection = _provider.GetConnection();
_channel = _provider.GetChannel();
}
catch (Exception ex)
{
//记录异常日志
Util.LogError($"RabbitMQPublisher createConnection exception. Exception message:{ex.Message}");
}
}
public IConnection Connection
{
get
{
if (_connection != null)
return _connection;
return _connection = _provider.GetConnection(); ;
}
//get; set;
}
private IModel _channel;
public IModel Channel
{
get
{
if (_channel != null)
return _channel;
else
{
//if (_connection == null || !_connection.IsOpen)
//{
// _connection = _provider.GetConnection(); ;
//}
return _channel = _provider.GetChannel();
}
}
}
///
/// 释放资源
///
public void Dispose()
{
if (Channel != null)
{
if (Channel.IsOpen)
Channel.Close();
Channel.Abort();
Channel.Dispose();
}
if (Connection != null)
{
if (Connection.IsOpen)
Connection.Close();
}
}
#endregion
}2、同步消息发送
///
/// 发布（生产）消息
///
/// 消息内容
/// 交换机名称
/// 队列名称
/// 交换机类型
/// 路由键
/// 是否持久化
/// 是否自动删除
/// 用于插件和代理特定功能，如消息TTL、队列长度限制等
/// 1.x-message-ttl 发送到队列的消息在丢弃之前可以存活多长时间（毫秒）。
/// 2.x-expires 队列在被自动删除（毫秒）之前可以使用多长时间。
/// 3.x-max-length 队列在开始从头部删除之前可以包含多少就绪消息。
/// 4.x-max-length-bytes 队列在开始从头部删除之前可以包含的就绪消息的总体大小。
/// 5.x-dead-letter-exchange 设置队列溢出行为。这决定了在达到队列的最大长度时消息会发生什么。有效值为drop-head或reject-publish。交换的可选名称，如果消息被拒绝或过期，将重新发布这些名称。
/// 6.x-dead-letter-routing-key 可选的替换路由密钥，用于在消息以字母为单位时使用。如果未设置，将使用消息的原始路由密钥。
/// 7.x-max-priority 队列支持的最大优先级数; 如果未设置，队列将不支持消息优先级。
/// 8.x-queue-mode 将队列设置为延迟模式，在磁盘上保留尽可能多的消息以减少内存使用;如果未设置，队列将保留内存缓存以尽快传递消息。
/// 9.x-queue-master-locator 将队列设置为主位置模式，确定在节点集群上声明时队列主机所在的规则。
private Task Publish(string message, string exchangeName, string queueName, string exchangeType, string routingKey = null, bool durable = true, bool autoDelete = false, IDictionary arguments = null)
{
if (x_message_ttl > 0)
{
arguments = new Dictionary();
arguments.Add("x-message-ttl", x_message_ttl);
}
//声明交换机
Channel.ExchangeDeclare(exchangeName, exchangeType, durable, autoDelete, arguments);
//声明队列
Channel.QueueDeclare(queueName, durable, false, autoDelete, arguments);
Channel.QueueBind(queue: queueName, exchange: exchangeName, routingKey == null ? string.Empty : routingKey);
var msgByte = Encoding.UTF8.GetBytes(message);
//设置消息持久化
var props = Channel.CreateBasicProperties();
props.Persistent = true;
try
{
Channel.TxSelect();
Channel.BasicPublish
(
exchange: exchangeName,
routingKey: routingKey == null ? string.Empty : routingKey,
mandatory: false,
basicProperties: props,
body: msgByte
);
Channel.TxCommit();
}
catch (Exception ex)
{
Channel.TxRollback();
//记录异常日志
Util.LogError($"RabbitMQPublisher publish message exception. Exception message:{ex.Message}");
}
return Task.FromResult(0);
}
3、批量发布
///
/// 批量发布
///
///
///
///
///
///
///
///
///
/// message, string exchangeName, string queueName, string exchangeType, string routingKey = null, bool durable = true, bool autoDelete = false, IDictionary arguments = null)
{
//using (var conn = _provider.ConnectionFactory.CreateConnection())
//{
using (var channel = Connection.CreateModel())
{
///Console.WriteLine(1);
if (x_message_ttl > 0)
{
arguments = new Dictionary();
arguments.Add("x-message-ttl", x_message_ttl);
}
//声明交换机
Channel.ExchangeDeclare(exchangeName, exchangeType, durable, autoDelete, arguments);
//声明队列
Channel.QueueDeclare(queueName, durable, false, autoDelete, arguments);
Channel.QueueBind(queue: queueName, exchange: exchangeName, routingKey == null ? string.Empty : routingKey);
//设置消息持久化
var props = Channel.CreateBasicProperties();
props.Persistent = true;
try
{
Channel.TxSelect();
var basicPublishBatch = Channel.CreateBasicPublishBatch();
byte[] msgByte;
ReadOnlyMemory memory;
foreach (var msg in message)
{
msgByte = Encoding.UTF8.GetBytes(msg);
memory = new ReadOnlyMemory(msgByte);
basicPublishBatch.Add
(
exchange: exchangeName,
routingKey: routingKey == null ? string.Empty : routingKey,
mandatory: false,
properties: props,
body: memory
);
}
basicPublishBatch.Publish();
Channel.TxCommit();
await Task.Yield();
}
catch (Exception ex)
{
Channel.TxRollback();
channel.Close(); channel.Dispose();
//conn.Close(); conn.Dispose();
//记录异常日志
Util.LogError($"RabbitMQPublisher publish message exception. Exception message:{ex.Message}");
Console.WriteLine("消息订阅时错误：" + ex.Message);
}
}
}
注意：多线程消息发布时，应避免多个线程使用同一个IModel实例，必须保证Imodel被一个线程独享，如果必须要多个线程访问呢一个实例的话，则可以通过加锁来处理，详见：.NET/C# Client API Guide — RabbitMQ
IModel ch = RetrieveSomeSharedIModelInstance();
lock (ch) {
ch.BasicPublish(...);
}三、消息订阅
1、获取连接、交换机和队列同上消息发布，不再赘述
private void QueueInitialization(string queueName, bool durable = true, bool autoDelete = false, IDictionary arguments = null)
{
try
{
if (x_message_ttl > 0)
{
arguments = new Dictionary();
arguments.Add("x-message-ttl", x_message_ttl);
}
Channel.QueueDeclare(queueName, durable, false, autoDelete, arguments);
}
catch (Exception )
{
}
} ///
///
///
///
///
///
/// 每次消费的消息条数
/// callback, bool autoAck, ushort consumPerTimes = 1)
{
try
{
QueueInitialization(queueName);
//声明为手动确认,每次只消费1条消息。
Channel.BasicQos(0, consumPerTimes, false);
//定义消费者
//var consumer = new EventingBasicConsumer(Channel);
var consumer = new AsyncEventingBasicConsumer(Channel);
//接收事件
consumer.Received += async (eventSender, args) =>
{
var message = args.Body.ToArray();//接收到的消息
var res = callback(Encoding.UTF8.GetString(message));
//返回消息确认
Channel.BasicAck(args.DeliveryTag, res);
await Task.Yield();
};
//开启监听 -- gai2023-11-1
Channel.BasicConsume(queueName, autoAck, consumer);
// await Task.Delay(1000);
}
catch (Exception e)
{
Console.WriteLine("消息订阅时错误：" + e.Message);
}
} 四、通过workerService订阅处理消息
internal class SubscribeWorker : BackgroundService
{
#region override
public override Task StartAsync(CancellationToken cancellationToken)
{
try
{
//一些数据初始化
_logger.LogInformation($"Settings 初始化完成");
}
catch (Exception ex)
{
_logger.LogError(ex, ex.Message);
}
return base.StartAsync(cancellationToken);
}
protected override async Task ExecuteAsync(CancellationToken stoppingToken)
{
//这里注意，不能写在while里，否则会一直进行重复订阅，会导致连接数一直增长
await MainSubscribe();
while (!stoppingToken.IsCancellationRequested)
{
try
{
await Task.Delay(2000);
}
catch (Exception ex)
{
_logger.LogError(ex, ex.Message);
}
}
}
///
/// 服务停止
///
///
///