Architecture 出版及;订阅模式与主题交换
我正在使用事件驱动体系结构开发缓存服务器,其工作原理如下: 我希望Architecture 出版及;订阅模式与主题交换,architecture,rabbitmq,message-queue,rpc,publish-subscribe,Architecture,Rabbitmq,Message Queue,Rpc,Publish Subscribe,我正在使用事件驱动体系结构开发缓存服务器,其工作原理如下: 我希望将发送到所有副本(扇出交换(?)的操作设置为并将获取操作设置为单个副本(默认交换(?) 我已经阅读了该模式,并且能够使用fanoutexchange使所有服务器响应。我读过关于这个模型的文章,能够做出任意的服务器响应。但我无法将这些方法统一到一个体系结构中。请帮忙 问题: 组织MQ以实现此行为的最佳方式是什么 我应该将两个队列绑定到一个交换机中吗 我想用correlationId从服务器响应到客户端。我应该重用现有队列/交换还是
将发送到所有副本(扇出交换(?)的操作设置为并将获取操作设置为单个副本(默认交换(?)
我已经阅读了该模式,并且能够使用fanoutexchange
使所有服务器响应。我读过关于这个模型的文章,能够做出任意的服务器响应。但我无法将这些方法统一到一个体系结构中。请帮忙
问题:
组织MQ以实现此行为的最佳方式是什么
我应该将两个队列绑定到一个交换机中吗
我想用correlationId
从服务器响应到客户端。我应该重用现有队列/交换还是创建新的队列/交换
您需要设置操作的队列。通过这种方式,N个客户端可以接收/响应消息。在浏览了您的问题域之后,我了解到的是-在运行时,多个客户端将向RabbitMQ发送“set”和“get”消息,每个“set”消息都将由此时处于活动状态的每个服务器缓存处理。而“get”消息需要由任何一个服务器缓存处理,并且需要将响应消息发送回发送“get”消息的客户端
如果我错了,请纠正我
在这种情况下,可以公平地假设客户端将有单独的触发点来生成/发布“get”/“set”消息。因此,逻辑上,“获取”消息生产者和“设置”消息发布者将是两个独立的程序/类
因此,您对发布/订阅和RPC模型的选择看起来是合乎逻辑的。您需要做的唯一一件事是将“set”和“get”消息处理和服务器缓存结合起来,这可以很容易地使用两个单独的通道(在同一连接中)来完成服务器缓存上的设置和获取消息各一个。请参阅下面附加的我的代码。我使用了相同示例的java代码(来自rabbitmq站点)这是您在问题中提到的。进行了一些小的修改,而且非常简单。在python中也不难做到这一点
现在来问你一些问题-
组织MQ以实现此行为的最佳方式是什么
您对发布/订阅和RPC模型的选择看起来合乎逻辑。
客户端将向exchange发布“set”消息(键入扇出,例如name“set_ex”),每个服务器缓存实例将侦听其绑定到exchange的临时队列(“set_ex”)。
客户端将向exchange生成“get”消息(键入Direct,例如name“get_ex”),队列“get_q”将与其队列名绑定到此exchange。每个服务器缓存都将侦听此get_q“。服务器缓存将结果消息发送到随“get”消息一起传递的临时队列名。一旦客户端收到响应消息,连接即关闭,临时队列即被删除(注意-在下面的示例代码中,我已将“get_q”绑定到默认exchange中,就像rabbitmq站点上的示例一样。但将“get_q”绑定到单独的exchange(直接键入)以提高可管理性并不困难。)
我应该将两个队列绑定到一个交换机中吗
我认为这不是一个正确的选择,因为对于发布/订阅场景,您将明确需要一个扇出交换,并且发送到扇出交换的每个消息都会复制到绑定到交换的每个队列。而且我们不希望将get消息推送到所有服务器缓存中
我想使用correlationId从服务器响应到客户端。
我应该重用现有队列/交换还是创建新的队列/交换
您所需要做的就是将响应消息从服务器发送到tempQueueName,该消息与原始“get”消息一起传递,正如rabbitmq提供的示例中所使用的那样
用于发布“设置”消息的客户端代码。
public class Client {
private static final String EXCHANGE_NAME_SET = "set_ex";
public static void main(String[] args) throws IOException, TimeoutException {
ConnectionFactory factory = new ConnectionFactory();
factory.setHost("localhost");
Connection connection = factory.newConnection();
Channel channel = connection.createChannel();
channel.exchangeDeclare(EXCHANGE_NAME_SET, BuiltinExchangeType.FANOUT);
String message = getMessage(args);
channel.basicPublish(EXCHANGE_NAME_SET, "", null, message.getBytes("UTF-8"));
System.out.println("Sent '" + message + "'");
channel.close();
connection.close();
}
private static String getMessage(String[] strings) {
if (strings.length < 1)
return "info: Hello World!";
return joinStrings(strings, " ");
}
private static String joinStrings(String[] strings, String delimiter) {
int length = strings.length;
if (length == 0)
return "";
StringBuilder words = new StringBuilder(strings[0]);
for (int i = 1; i < length; i++) {
words.append(delimiter).append(strings[i]);
}
return words.toString();
}
}
public class RPCClient {
private static final String EXCHANGE_NAME_GET = "get_ex";
private Connection connection;
private Channel channel;
private String requestQueueName = "get_q";
private String replyQueueName;
public RPCClient() throws IOException, TimeoutException {
ConnectionFactory factory = new ConnectionFactory();
factory.setHost("localhost");
connection = factory.newConnection();
channel = connection.createChannel();
replyQueueName = channel.queueDeclare().getQueue();
}
public String call(String message) throws IOException, InterruptedException {
String corrId = UUID.randomUUID().toString();
AMQP.BasicProperties props = new AMQP.BasicProperties
.Builder()
.correlationId(corrId)
.replyTo(replyQueueName)
.build();
//channel.basicPublish("", requestQueueName, props, message.getBytes("UTF-8"));
channel.basicPublish("", requestQueueName, props, message.getBytes("UTF-8"));
final BlockingQueue<String> response = new ArrayBlockingQueue<String>(1);
channel.basicConsume(replyQueueName, true, new DefaultConsumer(channel) {
@Override
public void handleDelivery(String consumerTag, Envelope envelope, AMQP.BasicProperties properties, byte[] body) throws IOException {
if (properties.getCorrelationId().equals(corrId)) {
response.offer(new String(body, "UTF-8"));
}
}
});
return response.take();
}
public void close() throws IOException {
connection.close();
}
public static void main(String[] args) throws IOException, TimeoutException {
RPCClient rpcClient = null;
String response = null;
try {
rpcClient = new RPCClient();
System.out.println(" sending get message");
response = rpcClient.call("30");
System.out.println(" Got '" + response + "'");
}
catch (IOException | TimeoutException | InterruptedException e) {
e.printStackTrace();
}
finally {
if (rpcClient!= null) {
try {
rpcClient.close();
}
catch (IOException _ignore) {}
}
}
}
}
public class ServerCache1 {
private static final String EXCHANGE_NAME_SET = "set_ex";
private static final String EXCHANGE_NAME_GET = "get_ex";
private static final String RPC_GET_QUEUE_NAME = "get_q";
private static final String s = UUID.randomUUID().toString();
public static void main(String[] args) throws IOException, TimeoutException {
System.out.println("Server Id " + s);
ConnectionFactory factory = new ConnectionFactory();
factory.setHost("localhost");
Connection connection = factory.newConnection();
// set server to receive and process set messages
Channel channelSet = connection.createChannel();
channelSet.exchangeDeclare(EXCHANGE_NAME_SET, BuiltinExchangeType.FANOUT);
String queueName = channelSet.queueDeclare().getQueue();
channelSet.queueBind(queueName, EXCHANGE_NAME_SET, "");
System.out.println("waiting for set message");
Consumer consumerSet = new DefaultConsumer(channelSet) {
@Override
public void handleDelivery(String consumerTag, Envelope envelope, AMQP.BasicProperties properties, byte[] body)
throws IOException {
String message = new String(body, "UTF-8");
System.out.println("Received '" + message + "'");
}
};
channelSet.basicConsume(queueName, true, consumerSet);
// here onwards following code is to set up Get message processing at Server cache
Channel channelGet = connection.createChannel();
channelGet.queueDeclare(RPC_GET_QUEUE_NAME, false, false, false, null);
channelGet.basicQos(1);
System.out.println("waiting for get message");
Consumer consumerGet = new DefaultConsumer(channelGet) {
@Override
public void handleDelivery(String consumerTag, Envelope envelope, AMQP.BasicProperties properties, byte[] body) throws IOException {
AMQP.BasicProperties replyProps = new AMQP.BasicProperties
.Builder()
.correlationId(properties.getCorrelationId())
.build();
System.out.println("received get message");
String response = "get response from server " + s;
channelGet.basicPublish( "", properties.getReplyTo(), replyProps, response.getBytes("UTF-8"));
channelGet.basicAck(envelope.getDeliveryTag(), false);
// RabbitMq consumer worker thread notifies the RPC server owner thread
synchronized(this) {
this.notify();
}
}
};
channelGet.basicConsume(RPC_GET_QUEUE_NAME, false, consumerGet);
// Wait and be prepared to consume the message from RPC client.
while (true) {
synchronized(consumerGet) {
try {
consumerGet.wait();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
}
希望这有帮助。据我所知,您正在使用RabbitMQ作为负载平衡器/服务发现机制。因此,您的客户机和缓存不需要了解彼此以及彼此的体系结构。您是否考虑过在缓存集群前面安装负载平衡器,它会更快,而且不会涉及:路由、队列、代理设置、相关ID等。