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如何使用ZooKeeper在Spring集成中实现分布式轮询锁

spring-cloud-zookeeper spring-integration-dsl apache-zookeeper spring-integration

suman j · 技术社区 · 7 年前

Spring集成具有ZooKeeper支持,如中所述 https://docs.spring.io/spring-integration/reference/html/zookeeper.html 然而,这份文件是如此模糊。

它建议在bean下面添加,但没有给出当节点被授予领导权时如何启动/停止轮询器的详细信息。

@Bean
public LeaderInitiatorFactoryBean leaderInitiator(CuratorFramework client) {
    return new LeaderInitiatorFactoryBean()
                .setClient(client)
                .setPath("/siTest/")
                .setRole("cluster");
}

我们有没有关于如何使用zookeeper确保在集群中任何时候只运行一次以下轮询器的示例?

@Component
public class EventsPoller {

    public void pullEvents() {
        //pull events should be run by only one node in the cluster at any time
    }
}

1 回复 | 直到 7 年前

Artem Bilan 7 年前

这个 LeaderInitiator 散发出 OnGrantedEvent 和 OnRevokedEvent ,当其成为领导者且其领导地位被撤销时。

看见 https://docs.spring.io/spring-integration/reference/html/messaging-endpoints-chapter.html#endpoint-roles https://docs.spring.io/spring-integration/reference/html/messaging-endpoints-chapter.html#leadership-event-handling 有关这些事件处理以及它如何影响特定角色中的组件的更多信息。

SmartLifecycleRoleController 章请随时就此事提出JIRA,欢迎您的贡献!

使现代化

@RunWith(SpringRunner.class)
@DirtiesContext
public class LeaderInitiatorFactoryBeanTests extends ZookeeperTestSupport {

    private static CuratorFramework client;

    @Autowired
    private PollableChannel stringsChannel;

    @BeforeClass
    public static void getClient() throws Exception {
        client = createNewClient();
    }

    @AfterClass
    public static void closeClient() {
        if (client != null) {
            client.close();
        }
    }

    @Test
    public void test() {
        assertNotNull(this.stringsChannel.receive(10_000));
    }


    @Configuration
    @EnableIntegration
    public static class Config {

        @Bean
        public LeaderInitiatorFactoryBean leaderInitiator(CuratorFramework client) {
            return new LeaderInitiatorFactoryBean()
                    .setClient(client)
                    .setPath("/siTest/")
                    .setRole("foo");
        }

        @Bean
        public CuratorFramework client() {
            return LeaderInitiatorFactoryBeanTests.client;
        }

        @Bean
        @InboundChannelAdapter(channel = "stringsChannel", autoStartup = "false", poller = @Poller(fixedDelay = "100"))
        @Role("foo")
        public Supplier<String> inboundChannelAdapter() {
            return () -> "foo";
        }

        @Bean
        public PollableChannel stringsChannel() {
            return new QueueChannel();
        }

    }

}

我有这样的日志:

2018-12-14 10:12:33,542 DEBUG [Curator-LeaderSelector-0] [org.springframework.integration.support.SmartLifecycleRoleController] - Starting [leaderInitiatorFactoryBeanTests.Config.inboundChannelAdapter.inboundChannelAdapter] in role foo
2018-12-14 10:12:33,578 DEBUG [Curator-LeaderSelector-0] [org.springframework.integration.support.SmartLifecycleRoleController] - Stopping [leaderInitiatorFactoryBeanTests.Config.inboundChannelAdapter.inboundChannelAdapter] in role foo