RabbitMQ的5種消息隊列

RabbitMQ的5種消息隊列

1、七種模式介紹與應用場景

1.1 簡單模式(Hello World)

在這里插入圖片描述

一個生產者對應一個消費者，RabbitMQ 相當于一個消息代理，負責將 A 的消息轉發給 B。

應用場景：將發送的電子郵件放到消息隊列，然后郵件服務在隊列中獲取郵件并發送給收件人。

1.2 工作隊列模式(Work queues)

在這里插入圖片描述

在多個消費者之間分配任務(競爭的消費者模式)，一個生產者對應多個消費者，一般適用于執行資源密集型任務，

單個消費者處理不過來，需要多個消費者進行處理。

應用場景：一個訂單的處理需要10s，有多個訂單可以同時放到消息隊列，然后讓多個消費者同時處理，這樣就是

并行了，而不是單個消費者的串行情況。

1.3 訂閱模式(Publish/Subscribe)

在這里插入圖片描述

一次向許多消費者發送消息，一個生產者發送的消息會被多個消費者獲取，也就是將消息將廣播到所有的消費者

中。

應用場景：更新商品庫存后需要通知多個緩存和多個數據庫，這里的結構應該是：

  • 一個 fanout 類型交換機扇出兩個個消息隊列，分別為緩存消息隊列、數據庫消息隊列
  • 一個緩存消息隊列對應著多個緩存消費者
  • 一個數據庫消息隊列對應著多個數據庫消費者

1.4 路由模式(Routing)

在這里插入圖片描述

有選擇地 (Routing key) 接收消息，發送消息到交換機并且要指定路由 key，消費者將隊列綁定到交換機時需要指

定路由 key，僅消費指定路由 key 的消息。

應用場景：如在商品庫存中增加了 1 臺 iphone12，iphone12 促銷活動消費者指定 routing key 為 iphone12，只

有此促銷活動會接收到消息，其它促銷活動不關心也不會消費此 routing key 的消息。

1.5 主題模式(Topics)

在這里插入圖片描述

根據主題 (Topics) 來接收消息，將路由 key 和某模式進行匹配，此時隊列需要綁定在一個模式上，#匹配一個詞

或多個詞，*只匹配一個詞。

應用場景：同上 iphone 促銷活動可以接收主題為 iphone 的消息，如 iphone12、iphone13 等。

1.6 遠程過程調用(RPC)

在這里插入圖片描述

如果我們需要在遠程計算機上運行功能并等待結果就可以使用 RPC，具體流程可以看圖。

應用場景：需要等待接口返回數據，如訂單支付。

1.7 發布者確認(Publisher Confirms)

與發布者進行可靠的發布確認，發布者確認是 RabbitMQ 擴展，可以實現可靠的發布。在通道上啟用發布者確認

后，RabbitMQ 將異步確認發送者發布的消息，這意味著它們已在服務器端處理。

應用場景：對于消息可靠性要求較高，比如錢包扣款。

2、代碼演示

<dependency><groupId>com.rabbitmq</groupId><artifactId>amqp-client</artifactId><version>5.6.0</version>
</dependency>

2.1 簡單模式

package simple;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;import java.io.IOException;
import java.util.concurrent.TimeoutException;public class Sender {private final static String QUEUE_NAME = "simple_queue";public static void main(String[] args) throws IOException, TimeoutException {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");factory.setPort(5672);Connection connection = factory.newConnection();Channel channel = connection.createChannel();// 聲明隊列// queue: 隊列名// durable: 是否持久化// exclusive: 是否排外,即只允許該channel訪問該隊列,一般等于true的話用于一個隊列只能有一個消費者來消費的場景// autoDelete: 是否自動刪除,消費完刪除// arguments: 其他屬性channel.queueDeclare(QUEUE_NAME, false, false, false, null);// 消息內容String message = "simplest mode message";channel.basicPublish("", QUEUE_NAME, null, message.getBytes());System.out.println("[x]Sent '" + message + "'");// 最后關閉通關和連接channel.close();connection.close();}
}

package simple;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.DeliverCallback;import java.io.IOException;
import java.util.concurrent.TimeoutException;public class Receiver {private final static String QUEUE_NAME = "simple_queue";public static void main(String[] args) throws IOException, TimeoutException {// 獲取連接ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");factory.setPort(5672);Connection connection = factory.newConnection();Channel channel = connection.createChannel();channel.queueDeclare(QUEUE_NAME, false, false, false, null);DeliverCallback deliverCallback = (consumerTag, delivery) -> {String message = new String(delivery.getBody(), "UTF-8");System.out.println(" [x] Received '" + delivery.getEnvelope().getRoutingKey() + "':'" + message + "'");};channel.basicConsume(QUEUE_NAME, true, deliverCallback, consumerTag -> {});}
}

[x]Sent 'simplest mode message'[x] Received 'simple_queue':'simplest mode message'

2.2 工作隊列模式

package work;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.DeliverCallback;import java.io.IOException;
import java.util.concurrent.TimeoutException;public class Receiver1 {private final static String QUEUE_NAME = "queue_work";public static void main(String[] args) throws IOException, TimeoutException {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");factory.setPort(5672);Connection connection = factory.newConnection();Channel channel = connection.createChannel();channel.queueDeclare(QUEUE_NAME, false, false, false, null);// 同一時刻服務器只會發送一條消息給消費者channel.basicQos(1);DeliverCallback deliverCallback = (consumerTag, delivery) -> {String message = new String(delivery.getBody(), "UTF-8");System.out.println(" [x-1] Received '" + delivery.getEnvelope().getRoutingKey() + "':'" + message + "'");};channel.basicConsume(QUEUE_NAME, true, deliverCallback, consumerTag -> {});}
}

package work;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.DeliverCallback;import java.io.IOException;
import java.util.concurrent.TimeoutException;public class Receiver2 {private final static String QUEUE_NAME = "queue_work";public static void main(String[] args) throws IOException, TimeoutException {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");factory.setPort(5672);Connection connection = factory.newConnection();Channel channel = connection.createChannel();channel.queueDeclare(QUEUE_NAME, false, false, false, null);// 同一時刻服務器只會發送一條消息給消費者channel.basicQos(1);DeliverCallback deliverCallback = (consumerTag, delivery) -> {String message = new String(delivery.getBody(), "UTF-8");System.out.println(" [x-2] Received '" + delivery.getEnvelope().getRoutingKey() + "':'" + message + "'");};channel.basicConsume(QUEUE_NAME, true, deliverCallback, consumerTag -> {});}
}

package work;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;import java.io.IOException;
import java.util.concurrent.TimeoutException;public class Sender {private final static String QUEUE_NAME = "queue_work";public static void main(String[] args) throws IOException, InterruptedException, TimeoutException {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");factory.setPort(5672);Connection connection = factory.newConnection();Channel channel = connection.createChannel();// 聲明隊列channel.queueDeclare(QUEUE_NAME, false, false, false, null);for (int i = 0; i < 10; i++) {String message = "work mode message" + i;channel.basicPublish("", QUEUE_NAME, null, message.getBytes());System.out.println("[x] Sent '" + message + "'");Thread.sleep(i * 10);}channel.close();connection.close();}
}

[x] Sent 'work mode message0'
[x] Sent 'work mode message1'
[x] Sent 'work mode message2'
[x] Sent 'work mode message3'
[x] Sent 'work mode message4'
[x] Sent 'work mode message5'
[x] Sent 'work mode message6'
[x] Sent 'work mode message7'
[x] Sent 'work mode message8'
[x] Sent 'work mode message9'[x-1] Received 'queue_work':'work mode message0'
[x-1] Received 'queue_work':'work mode message2'
[x-1] Received 'queue_work':'work mode message4'
[x-1] Received 'queue_work':'work mode message6'
[x-1] Received 'queue_work':'work mode message8'[x-2] Received 'queue_work':'work mode message1'
[x-2] Received 'queue_work':'work mode message3'
[x-2] Received 'queue_work':'work mode message5'
[x-2] Received 'queue_work':'work mode message7'
[x-2] Received 'queue_work':'work mode message9'

2.3 發布訂閱模式

package publishsubscribe;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.DeliverCallback;public class Receive1 {private static final String EXCHANGE_NAME = "logs";public static void main(String[] argv) throws Exception {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");Connection connection = factory.newConnection();Channel channel = connection.createChannel();channel.exchangeDeclare(EXCHANGE_NAME, "fanout");String queueName = channel.queueDeclare().getQueue();channel.queueBind(queueName, EXCHANGE_NAME, "");System.out.println(" [*] Waiting for messages. To exit press CTRL+C");// 訂閱消息的回調函數DeliverCallback deliverCallback = (consumerTag, delivery) -> {String message = new String(delivery.getBody(), "UTF-8");System.out.println(" [x-1] Received '" + message + "'");};// 消費者，有消息時出發訂閱回調函數channel.basicConsume(queueName, true, deliverCallback, consumerTag -> {});}
}

package publishsubscribe;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.DeliverCallback;public class Receive2 {private static final String EXCHANGE_NAME = "logs";public static void main(String[] argv) throws Exception {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");Connection connection = factory.newConnection();Channel channel = connection.createChannel();channel.exchangeDeclare(EXCHANGE_NAME, "fanout");String queueName = channel.queueDeclare().getQueue();channel.queueBind(queueName, EXCHANGE_NAME, "");System.out.println(" [*] Waiting for messages. To exit press CTRL+C");// 訂閱消息的回調函數DeliverCallback deliverCallback = (consumerTag, delivery) -> {String message = new String(delivery.getBody(), "UTF-8");System.out.println(" [x-2] Received2 '" + message + "'");};// 消費者，有消息時出發訂閱回調函數channel.basicConsume(queueName, true, deliverCallback, consumerTag -> {});}
}

package publishsubscribe;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;public class Sender {private static final String EXCHANGE_NAME = "logs";public static void main(String[] argv) throws Exception {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");Connection connection = factory.newConnection();Channel channel = connection.createChannel();channel.exchangeDeclare(EXCHANGE_NAME, "fanout");String message = "publish subscribe message";channel.basicPublish(EXCHANGE_NAME, "", null, message.getBytes("UTF-8"));System.out.println(" [x] Sent '" + message + "'");channel.close();connection.close();}
}

[x] Sent 'publish subscribe message'[*] Waiting for messages. To exit press CTRL+C
[x-1] Received 'publish subscribe message'[*] Waiting for messages. To exit press CTRL+C
[x-2] Received2 'publish subscribe message'

2.4 路由模式

package router;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.DeliverCallback;import java.io.IOException;
import java.util.concurrent.TimeoutException;public class Receiver1 {private final static String QUEUE_NAME = "queue_routing";private final static String EXCHANGE_NAME = "exchange_direct";public static void main(String[] args) throws IOException, TimeoutException {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");factory.setPort(5672);Connection connection = factory.newConnection();Channel channel = connection.createChannel();channel.queueDeclare(QUEUE_NAME, false, false, false, null);// 指定路由的key,接收key和key2channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, "key");channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, "key2");channel.basicQos(1);DeliverCallback deliverCallback = (consumerTag, delivery) -> {String message = new String(delivery.getBody(), "UTF-8");System.out.println(" [x-1] Received '" + delivery.getEnvelope().getRoutingKey() + "':'" + message + "'");};channel.basicConsume(QUEUE_NAME, true, deliverCallback, consumerTag -> {});}
}

package router;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.DeliverCallback;import java.io.IOException;
import java.util.concurrent.TimeoutException;public class Receiver2 {private final static String QUEUE_NAME = "queue_routing2";private final static String EXCHANGE_NAME = "exchange_direct";public static void main(String[] args) throws IOException, TimeoutException {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");factory.setPort(5672);Connection connection = factory.newConnection();Channel channel = connection.createChannel();channel.queueDeclare(QUEUE_NAME, false, false, false, null);// 僅接收key2channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, "key2");channel.basicQos(1);DeliverCallback deliverCallback = (consumerTag, delivery) -> {String message = new String(delivery.getBody(), "UTF-8");System.out.println(" [x-2] Received '" +delivery.getEnvelope().getRoutingKey() + "':'" + message + "'");};channel.basicConsume(QUEUE_NAME, true, deliverCallback, consumerTag -> {});}
}

package router;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;import java.io.IOException;
import java.util.concurrent.TimeoutException;public class Sender {private final static String EXCHANGE_NAME = "exchange_direct";private final static String EXCHANGE_TYPE = "direct";public static void main(String[] args) throws IOException, TimeoutException {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");factory.setPort(5672);Connection connection = factory.newConnection();Channel channel = connection.createChannel();// 交換機聲明channel.exchangeDeclare(EXCHANGE_NAME, EXCHANGE_TYPE);// 只有routingKey相同的才會消費String message = "routing mode message";channel.basicPublish(EXCHANGE_NAME, "key2", null, message.getBytes());System.out.println("[x] Sent '" + message + "'");// channel.basicPublish(EXCHANGE_NAME, "key", null, message.getBytes());// System.out.println("[x] Sent '" + message + "'");channel.close();connection.close();}
}

[x] Sent 'routing mode message'[x-1] Received 'key2':'routing mode message'[x-2] Received 'key2':'routing mode message'

2.5 主題模式

package topic;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.DeliverCallback;import java.io.IOException;
import java.util.concurrent.TimeoutException;public class Receiver1 {private final static String QUEUE_NAME = "queue_topic";private final static String EXCHANGE_NAME = "exchange_topic";public static void main(String[] args) throws IOException, InterruptedException, TimeoutException {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");factory.setPort(5672);Connection connection = factory.newConnection();Channel channel = connection.createChannel();channel.queueDeclare(QUEUE_NAME, false, false, false, null);// 可以接收key.1channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, "key.*");channel.basicQos(1);DeliverCallback deliverCallback = (consumerTag, delivery) -> {String message = new String(delivery.getBody(), "UTF-8");System.out.println(" [x-1] Received '" + delivery.getEnvelope().getRoutingKey() + "':'" + message + "'");};channel.basicConsume(QUEUE_NAME, true, deliverCallback, consumerTag -> {});}
}

package topic;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.DeliverCallback;import java.io.IOException;
import java.util.concurrent.TimeoutException;public class Receiver2 {private final static String QUEUE_NAME = "queue_topic2";private final static String EXCHANGE_NAME = "exchange_topic";private final static String EXCHANGE_TYPE = "topic";public static void main(String[] args) throws IOException, InterruptedException, TimeoutException {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");factory.setPort(5672);Connection connection = factory.newConnection();Channel channel = connection.createChannel();channel.queueDeclare(QUEUE_NAME, false, false, false, null);// *號代表單個單詞，可以接收key.1channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, "*.*");// #號代表多個單詞，可以接收key.1.2channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, "*.#");channel.basicQos(1);DeliverCallback deliverCallback = (consumerTag, delivery) -> {String message = new String(delivery.getBody(), "UTF-8");System.out.println(" [x-2] Received '" + delivery.getEnvelope().getRoutingKey() + "':'" + message + "'");};channel.basicConsume(QUEUE_NAME, true, deliverCallback, consumerTag -> {});}
}

package topic;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;import java.io.IOException;
import java.util.concurrent.TimeoutException;public class Sender {private final static String EXCHANGE_NAME = "exchange_topic";private final static String EXCHANGE_TYPE = "topic";public static void main(String[] args) throws IOException, TimeoutException {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");factory.setPort(5672);Connection connection = factory.newConnection();Channel channel = connection.createChannel();channel.exchangeDeclare(EXCHANGE_NAME, EXCHANGE_TYPE);String message = "topics model message with key.1";channel.basicPublish(EXCHANGE_NAME, "key.1", null, message.getBytes());System.out.println("[x] Sent '" + message + "'");String message2 = "topics model message with key.1.2";channel.basicPublish(EXCHANGE_NAME, "key.1.2", null, message2.getBytes());System.out.println("[x] Sent '" + message2 + "'");channel.close();connection.close();}
}

[x] Sent 'topics model message with key.1'
[x] Sent 'topics model message with key.1.2'[x-1] Received 'key.1':'topics model message with key.1'[x-2] Received 'key.1':'topics model message with key.1'
[x-2] Received 'key.1.2':'topics model message with key.1.2'

3、四種交換機介紹

  • 直連交換機( Direct exchange )：具有路由功能的交換機，綁定到此交換機的時候需要指定一個

    routing_key，交換機發送消息的時候需要 routing_key，會將消息發送道對應的隊列。

  • 扇形交換機( Fanout exchange )：廣播消息到所有隊列，沒有任何處理，速度最快。

  • 主題交換機( Topic exchange )：在直連交換機基礎上增加模式匹配，也就是對 routing_key 進行模式匹配，

    * 代表一個單詞，# 代表多個單詞。

  • 首部交換機( Headers exchange )：忽略 routing_key，使用 Headers 信息(一個 Hash 的數據結構)進行匹

    配，優勢在于可以有更多更靈活的匹配規則。

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