Delay via Camel

Camel delay 和 throttle 将从 ActiveMQ 队列中删除(消耗)消息并将其保留(在内存中)在路由中直到处理.事务 JMS 可能会缓解有关丢失消息的问题，尚未尝试过.值得深思.

Delay via Camel

Camel delay and throttle will remove (consume) the message from ActiveMQ queue and keep it (in-memory) in the route until processed. Transacted JMS might alleviate issues concerning losing the message, haven't tried that yet. Food for thought.

我使用 AMQ_SCHEDULED_DELAY 标头结合启用 schedulerSupport [1, 2, 3, 4、5、6一个>].这是根据 JMS 2.0 交付延迟.

I got it to work in Spring Boot 2 with Camel and ActiveMQ using the AMQ_SCHEDULED_DELAY header combined with enabling schedulerSupport [1, 2, 3, 4, 5, 6]. This is per JMS 2.0 Delivery Delay.

请注意，只有当没有活动消费者时，消息才会出现在 ActiveMQ 队列中(pending) - 即应用程序关闭或 Camel 路由禁用.下面的配置用于使用现有 ActiveMQ 代理.

Note that a message will only appear in the ActiveMQ queue (pending) when there are no active consumers - i.e. application down or Camel route disabled. Configuration below is for using an existing ActiveMQ broker.

application.properties(来源)

spring.activemq.broker-url=tcp://localhost:61616

RouteBuilder

from("jms://incomingQueue").setHeader("AMQ_SCHEDULED_DELAY", constant("1000")).inOnly("jms://delayedQueue");  

from("jms://delayedQueue").process(...);

activemq.xml(现有代理安装)

<broker xmlns="http://activemq.apache.org/schema/core" brokerName="localhost" dataDirectory="${activemq.data}" schedulerSupport="true">  

对于在 /usr/local/Cellar/activemq//libexec/conf 下找到的 OSX Homebrew.

For OSX Homebrew found under /usr/local/Cellar/activemq/<version>/libexec/conf.

如果您想在您的应用程序中使用嵌入代理，您可以使用 BrokerService.

If you want to use a broker embedded in your application you can use the BrokerService.

默认情况下，数据保存在 activemq-data 中，并且需要 activemq-kahadb-store 依赖项 - 如果您选择 JDBC(来源).使用 brokerService.setPersistent( false ) 不再需要存储依赖项，但是 JMS 消息会再次存储在内存中.

By default data is persisted in activemq-data and requires the activemq-kahadb-store dependency - also if you chose JDBC (source). Using brokerService.setPersistent( false ) the store dependency is no longer required, but then the JMS message is stored in-memory again.

@Bean
public BrokerService brokerService()
{
    BrokerService brokerService = new BrokerService();
    brokerService.setSchedulerSupport( true );
    return brokerService;
}

可以找到更多示例 此处 和此处.

Further examples can be found here and here.