Spring integration 如何使用ZooKeeper在Spring集成中实现分布式轮询锁

Spring集成具有ZooKeeper支持，如中所述 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
    }
}

---

LeaderInitiator

在成为leader且其领导权被撤销时发出

OnGrantedEvent

和

OnRevokedEvent

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，请参阅和下一页

虽然我同意Zookkeper章节必须有一些链接到

SmartLifecycleRoleController

章节。请随时就此事提出JIRA，欢迎您的贡献

更新

这就是我在测试中所做的：

@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();
        }

    }

}

---

你有没有任何简单的民意调查者被动物园管理员选举控制的例子？我尝试实现SmartLifecycle，向leaderInitiator bean添加一个DefaultCandidate。但我仍然没有看到zookeeper调用或控制生命周期方法。想知道是否有简单民意测验的例子？请看我答案中的更新。

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