聊聊spring-cloud的ConsulServiceRegistry

39次阅读

共计 7543 个字符，预计需要花费 19 分钟才能阅读完成。

序

本文主要研究一下 spring cloud 的 ConsulServiceRegistry

ServiceRegistry

spring-cloud-commons-2.1.2.RELEASE-sources.jar!/org/springframework/cloud/client/serviceregistry/ServiceRegistry.java

public interface ServiceRegistry<R extends Registration> {

    /**
     * Registers the registration. A registration typically has information about an
     * instance, such as its hostname and port.
     * @param registration registration meta data
     */
    void register(R registration);

    /**
     * Deregisters the registration.
     * @param registration registration meta data
     */
    void deregister(R registration);

    /**
     * Closes the ServiceRegistry. This is a lifecycle method.
     */
    void close();

    /**
     * Sets the status of the registration. The status values are determined by the
     * individual implementations.
     * @param registration The registration to update.
     * @param status The status to set.
     * @see org.springframework.cloud.client.serviceregistry.endpoint.ServiceRegistryEndpoint
     */
    void setStatus(R registration, String status);

    /**
     * Gets the status of a particular registration.
     * @param registration The registration to query.
     * @param <T> The type of the status.
     * @return The status of the registration.
     * @see org.springframework.cloud.client.serviceregistry.endpoint.ServiceRegistryEndpoint
     */
    <T> T getStatus(R registration);

}
  • ServiceRegistry 接口定义了 register、deregister、close、setStatus、getStatus 方法

ConsulServiceRegistry

spring-cloud-consul-discovery-2.1.2.RELEASE-sources.jar!/org/springframework/cloud/consul/serviceregistry/ConsulServiceRegistry.java

public class ConsulServiceRegistry implements ServiceRegistry<ConsulRegistration> {private static Log log = LogFactory.getLog(ConsulServiceRegistry.class);

    private final ConsulClient client;

    private final ConsulDiscoveryProperties properties;

    private final TtlScheduler ttlScheduler;

    private final HeartbeatProperties heartbeatProperties;

    public ConsulServiceRegistry(ConsulClient client,
            ConsulDiscoveryProperties properties, TtlScheduler ttlScheduler,
            HeartbeatProperties heartbeatProperties) {
        this.client = client;
        this.properties = properties;
        this.ttlScheduler = ttlScheduler;
        this.heartbeatProperties = heartbeatProperties;
    }

    @Override
    public void register(ConsulRegistration reg) {log.info("Registering service with consul:" + reg.getService());
        try {this.client.agentServiceRegister(reg.getService(),
                    this.properties.getAclToken());
            NewService service = reg.getService();
            if (this.heartbeatProperties.isEnabled() && this.ttlScheduler != null
                    && service.getCheck() != null
                    && service.getCheck().getTtl() != null) {this.ttlScheduler.add(reg.getInstanceId());
            }
        }
        catch (ConsulException e) {if (this.properties.isFailFast()) {log.error("Error registering service with consul:" + reg.getService(),
                        e);
                ReflectionUtils.rethrowRuntimeException(e);
            }
            log.warn("Failfast is false. Error registering service with consul:"
                    + reg.getService(), e);
        }
    }

    @Override
    public void deregister(ConsulRegistration reg) {if (this.ttlScheduler != null) {this.ttlScheduler.remove(reg.getInstanceId());
        }
        if (log.isInfoEnabled()) {log.info("Deregistering service with consul:" + reg.getInstanceId());
        }
        this.client.agentServiceDeregister(reg.getInstanceId(),
                this.properties.getAclToken());
    }

    @Override
    public void close() {}

    @Override
    public void setStatus(ConsulRegistration registration, String status) {if (status.equalsIgnoreCase(OUT_OF_SERVICE.getCode())) {this.client.agentServiceSetMaintenance(registration.getInstanceId(), true);
        }
        else if (status.equalsIgnoreCase(UP.getCode())) {this.client.agentServiceSetMaintenance(registration.getInstanceId(), false);
        }
        else {throw new IllegalArgumentException("Unknown status:" + status);
        }

    }

    @Override
    public Object getStatus(ConsulRegistration registration) {String serviceId = registration.getServiceId();
        Response<List<Check>> response = this.client.getHealthChecksForService(serviceId,
                QueryParams.DEFAULT);
        List<Check> checks = response.getValue();

        for (Check check : checks) {if (check.getServiceId().equals(registration.getInstanceId())) {if (check.getName().equalsIgnoreCase("Service Maintenance Mode")) {return OUT_OF_SERVICE.getCode();
                }
            }
        }

        return UP.getCode();}

}
  • ConsulServiceRegistry 实现了 ServiceRegistry 方法，其构造器接收 ConsulClient、ConsulDiscoveryProperties、TtlScheduler、HeartbeatProperties 参数
  • 其 regiter 方法使用 ConsulClient 的 agentServiceRegister 注册服务，如果开启 heartbeat 并设置 ttl 的话，会注册一个 heartbeat 的延时任务；deregister 方法使用 ConsulClient 的 agentServiceDeregister 注销服务，同时从 ttlScheduler 移除该 instance 的延时任务
  • setStatus 方法对 OUT_OF_SERVICE 执行 client.agentServiceSetMaintenance(registration.getInstanceId(), true)，对 UP 执行 client.agentServiceSetMaintenance(registration.getInstanceId(), false)；getStatus 方法通过 client.getHealthChecksForService(serviceId,QueryParams.DEFAULT) 获取 Check 列表，一旦有 Service Maintenance Mode 的 check 立即返回 OUT_OF_SERVICE

ConsulRegistration

spring-cloud-consul-discovery-2.1.2.RELEASE-sources.jar!/org/springframework/cloud/consul/serviceregistry/ConsulRegistration.java

public class ConsulRegistration implements Registration {

    private final NewService service;

    private ConsulDiscoveryProperties properties;

    public ConsulRegistration(NewService service, ConsulDiscoveryProperties properties) {
        this.service = service;
        this.properties = properties;
    }

    public NewService getService() {return this.service;}

    protected ConsulDiscoveryProperties getProperties() {return this.properties;}

    public String getInstanceId() {return getService().getId();}

    public String getServiceId() {return getService().getName();}

    @Override
    public String getHost() {return getService().getAddress();}

    @Override
    public int getPort() {return getService().getPort();}

    @Override
    public boolean isSecure() {return this.properties.getScheme().equalsIgnoreCase("https");
    }

    @Override
    public URI getUri() {return DefaultServiceInstance.getUri(this);
    }

    @Override
    public Map<String, String> getMetadata() {return ConsulServerUtils.getMetadata(getService().getTags());
    }

}
  • ConsulRegistration 实现了 Registration 接口，其 getMetadata 方法返回的是 ConsulServerUtils.getMetadata(getService().getTags())

ConsulServiceRegistryAutoConfiguration

spring-cloud-consul-discovery-2.1.2.RELEASE-sources.jar!/org/springframework/cloud/consul/serviceregistry/ConsulServiceRegistryAutoConfiguration.java

@Configuration
@ConditionalOnConsulEnabled
@ConditionalOnProperty(value = "spring.cloud.service-registry.enabled", matchIfMissing = true)
@AutoConfigureBefore(ServiceRegistryAutoConfiguration.class)
public class ConsulServiceRegistryAutoConfiguration {@Autowired(required = false)
    private TtlScheduler ttlScheduler;

    @Bean
    @ConditionalOnMissingBean
    public ConsulServiceRegistry consulServiceRegistry(ConsulClient consulClient,
            ConsulDiscoveryProperties properties,
            HeartbeatProperties heartbeatProperties) {
        return new ConsulServiceRegistry(consulClient, properties, this.ttlScheduler,
                heartbeatProperties);
    }

    @Bean
    @ConditionalOnMissingBean
    @ConditionalOnProperty("spring.cloud.consul.discovery.heartbeat.enabled")
    public TtlScheduler ttlScheduler(ConsulClient consulClient,
            HeartbeatProperties heartbeatProperties) {return new TtlScheduler(heartbeatProperties, consulClient);
    }

    @Bean
    @ConditionalOnMissingBean
    public HeartbeatProperties heartbeatProperties() {return new HeartbeatProperties();
    }

    @Bean
    @ConditionalOnMissingBean
    public ConsulDiscoveryProperties consulDiscoveryProperties(InetUtils inetUtils) {return new ConsulDiscoveryProperties(inetUtils);
    }

}
  • ConsulServiceRegistryAutoConfiguration 注册了 ConsulServiceRegistry、TtlScheduler、HeartbeatProperties、ConsulDiscoveryProperties

小结

  • ConsulServiceRegistry 实现了 ServiceRegistry 方法，其构造器接收 ConsulClient、ConsulDiscoveryProperties、TtlScheduler、HeartbeatProperties 参数
  • 其 regiter 方法使用 ConsulClient 的 agentServiceRegister 注册服务，如果开启 heartbeat 并设置 ttl 的话，会注册一个 heartbeat 的延时任务；deregister 方法使用 ConsulClient 的 agentServiceDeregister 注销服务，同时从 ttlScheduler 移除该 instance 的延时任务
  • setStatus 方法对 OUT_OF_SERVICE 执行 client.agentServiceSetMaintenance(registration.getInstanceId(), true)，对 UP 执行 client.agentServiceSetMaintenance(registration.getInstanceId(), false)；getStatus 方法通过 client.getHealthChecksForService(serviceId,QueryParams.DEFAULT) 获取 Check 列表，一旦有 Service Maintenance Mode 的 check 立即返回 OUT_OF_SERVICE

doc

  • spring-cloud-consul-discovery

正文完
consul
发表至：无分类
2019-07-23
 0