版本
- springboot 2.0.1.RELEASE
- springcloud Finchley.RC1
问题
看程序猿 dd 的博客 http://blog.didispace.com/Spring-Cloud-Config-Server-ip-change-problem/
容器中 config-server 重启或迁移导致ip port 变动, config-client 依旧使用老的(从eureka 第一次取到)的config-server 地址.导致 bus 无法刷新配置,healbeat config 失败.
进一步发现问题
ConfigServicePropertySourceLocator.java
private Environment getRemoteEnvironment(RestTemplate restTemplate, ConfigClientProperties properties,
String label, String state) {
String path = "/{name}/{profile}";
String name = properties.getName();
String profile = properties.getProfile();
String token = properties.getToken();
String uri = properties.getRawUri();
Object[] args = new String[] { name, profile };
if (StringUtils.hasText(label)) {
args = new String[] { name, profile, label };
path = path + "/{label}";
}
ResponseEntity<Environment> response = null;
try {
HttpHeaders headers = new HttpHeaders();
if (StringUtils.hasText(token)) {
headers.add(TOKEN_HEADER, token);
}
if (StringUtils.hasText(state)) { //TODO: opt in to sending state?
headers.add(STATE_HEADER, state);
}
final HttpEntity<Void> entity = new HttpEntity<>((Void) null, headers);
//uri 是直接从配置中拿的
response = restTemplate.exchange(uri + path, HttpMethod.GET,
entity, Environment.class, args);
}
catch (HttpClientErrorException e) {
if (e.getStatusCode() != HttpStatus.NOT_FOUND) {
throw e;
}
}
if (response == null || response.getStatusCode() != HttpStatus.OK) {
return null;
}
Environment result = response.getBody();
return result;
}
虽然从上面代码可以看出,config-client 获取 config-server 地址,是从配置中获取.
但是有下面代码.
@ConditionalOnProperty(value = "spring.cloud.config.discovery.enabled", matchIfMissing = false)
@Configuration
@Import({ UtilAutoConfiguration.class })
@EnableDiscoveryClient
public class DiscoveryClientConfigServiceBootstrapConfiguration {
private static Log logger = LogFactory
.getLog(DiscoveryClientConfigServiceBootstrapConfiguration.class);
@Autowired
private ConfigClientProperties config;
@Autowired
private ConfigServerInstanceProvider instanceProvider;
private HeartbeatMonitor monitor = new HeartbeatMonitor();
@Bean
public ConfigServerInstanceProvider configServerInstanceProvider(
DiscoveryClient discoveryClient) {
return new ConfigServerInstanceProvider(discoveryClient);
}
@EventListener(ContextRefreshedEvent.class)
public void startup(ContextRefreshedEvent event) {
//刷新配置
refresh();
}
@EventListener(HeartbeatEvent.class)
public void heartbeat(HeartbeatEvent event) {
if (monitor.update(event.getValue())) {
//刷新配置
refresh();
}
}
private void refresh() {
try {
String serviceId = this.config.getDiscovery().getServiceId();
ServiceInstance server = this.instanceProvider
.getConfigServerInstance(serviceId);
String url = getHomePage(server);
if (server.getMetadata().containsKey("password")) {
String user = server.getMetadata().get("user");
user = user == null ? "user" : user;
this.config.setUsername(user);
String password = server.getMetadata().get("password");
this.config.setPassword(password);
}
if (server.getMetadata().containsKey("configPath")) {
String path = server.getMetadata().get("configPath");
if (url.endsWith("/") && path.startsWith("/")) {
url = url.substring(0, url.length() - 1);
}
url = url + path;
}
this.config.setUri(url);
}
catch (Exception ex) {
if (config.isFailFast()) {
throw ex;
}
else {
logger.warn("Could not locate configserver via discovery", ex);
}
}
}
private String getHomePage(ServiceInstance server) {
return server.getUri().toString() + "/";
}
}
两个事件,ContextRefreshedEvent 和 HeartbeatEvent 都会触发刷新 ConfigClientProperties 中的 uri 地址. HeartbeatEvent 的触发是在 CloudEurekaClient.java
@Override
protected void onCacheRefreshed() {
super.onCacheRefreshed();
if (this.cacheRefreshedCount != null) { //might be called during construction and will be null
long newCount = this.cacheRefreshedCount.incrementAndGet();
log.trace("onCacheRefreshed called with count: " + newCount);
this.publisher.publishEvent(new HeartbeatEvent(this, newCount));
}
}
即DiscoveryClient.java 中
private boolean fetchRegistry(boolean forceFullRegistryFetch) {
Stopwatch tracer = FETCH_REGISTRY_TIMER.start();
try {
// If the delta is disabled or if it is the first time, get all
// applications
Applications applications = getApplications();
if (clientConfig.shouldDisableDelta()
|| (!Strings.isNullOrEmpty(clientConfig.getRegistryRefreshSingleVipAddress()))
|| forceFullRegistryFetch
|| (applications == null)
|| (applications.getRegisteredApplications().size() == 0)
|| (applications.getVersion() == -1)) //Client application does not have latest library supporting delta
{
logger.info("Disable delta property : {}", clientConfig.shouldDisableDelta());
logger.info("Single vip registry refresh property : {}", clientConfig.getRegistryRefreshSingleVipAddress());
logger.info("Force full registry fetch : {}", forceFullRegistryFetch);
logger.info("Application is null : {}", (applications == null));
logger.info("Registered Applications size is zero : {}",
(applications.getRegisteredApplications().size() == 0));
logger.info("Application version is -1: {}", (applications.getVersion() == -1));
getAndStoreFullRegistry();
} else {
getAndUpdateDelta(applications);
}
applications.setAppsHashCode(applications.getReconcileHashCode());
logTotalInstances();
} catch (Throwable e) {
logger.error(PREFIX + "{} - was unable to refresh its cache! status = {}", appPathIdentifier, e.getMessage(), e);
return false;
} finally {
if (tracer != null) {
tracer.stop();
}
}
// Notify about cache refresh before updating the instance remote status
onCacheRefreshed();
// Update remote status based on refreshed data held in the cache
updateInstanceRemoteStatus();
// registry was fetched successfully, so return true
return true;
}
那么,我们是不是可以认为,当 eureka 同步注册信息的后,会触发事件,修改ConfigClientProperties的配置.
然后这个问题就已经解决了呢(只有当 eureka client 还没同步注册信息,且 config-server 的 ip port 变动,这时候有 bus 和 healbeat 才会出问题 ps:几率相当之低,可以忽略)
事情没有这么简单.
笔者变更 config-server 的地址后,debug config-client 发现,在上述DiscoveryClientConfigServiceBootstrapConfiguration.refresh 方法的时候,取到的 url, 依旧是老的可不用的 config-server 地址.
图一是 DiscoveryClientConfigServiceBootstrapConfiguration.refresh() debug
图二是 DiscoveryClient.fetchRegistry debug
明显可以看到 两个 CloudEurekaClient 不一致,图一叫9962,图二叫9926.
说明CloudEurekaClient 创建了两次.且 DiscoveryClientConfigServiceBootstrapConfiguration 中获得 config-server 地址的CloudEurekaClient是无效的.
再进一步深究
在 spring-cloud-config-client 的 spring.factories中
# Bootstrap components
org.springframework.cloud.bootstrap.BootstrapConfiguration=\
org.springframework.cloud.config.client.ConfigServiceBootstrapConfiguration,\
org.springframework.cloud.config.client.DiscoveryClientConfigServiceBootstrapConfiguration
DiscoveryClientConfigServiceBootstrapConfiguration 的初始化等级太高,ConfigServerInstanceProvider 持有的DiscoveryClient 无法修改,永远都是老对象.导致每次refresh 操作,获取的 config-server 地址都是老的.
解决方案
想了半天,没有找到不侵入的方式修改.只好魔改 spring-cloud-config-client 的代码.
修改DiscoveryClientConfigServiceBootstrapConfiguration.java
/*
* Copyright 2013-2014 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.cloud.config.client;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.client.discovery.event.HeartbeatEvent;
import org.springframework.cloud.client.discovery.event.HeartbeatMonitor;
import org.springframework.cloud.commons.util.UtilAutoConfiguration;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.context.event.ContextRefreshedEvent;
import org.springframework.context.event.EventListener;
/**
* Bootstrap configuration for a config client that wants to lookup the config server via
* discovery.
*
* @author Dave Syer
*/
@ConditionalOnProperty(value = "spring.cloud.config.discovery.enabled", matchIfMissing = false)
@Configuration
@Import({ UtilAutoConfiguration.class })
@EnableDiscoveryClient
public class DiscoveryClientConfigServiceBootstrapConfiguration {
private static Log logger = LogFactory
.getLog(DiscoveryClientConfigServiceBootstrapConfiguration.class);
@Autowired
private ConfigClientProperties config;
@Autowired
private ConfigServerInstanceProvider instanceProvider;
// private HeartbeatMonitor monitor = new HeartbeatMonitor();
@Bean
public ConfigServerInstanceProvider configServerInstanceProvider(
DiscoveryClient discoveryClient) {
return new ConfigServerInstanceProvider(discoveryClient);
}
@EventListener(ContextRefreshedEvent.class)
public void startup(ContextRefreshedEvent event) {
refresh();
}
// @EventListener(HeartbeatEvent.class)
// public void heartbeat(HeartbeatEvent event) {
// if (monitor.update(event.getValue())) {
// refresh();
// }
// }
private void refresh() {
try {
String serviceId = this.config.getDiscovery().getServiceId();
ServiceInstance server = this.instanceProvider
.getConfigServerInstance(serviceId);
String url = getHomePage(server);
if (server.getMetadata().containsKey("password")) {
String user = server.getMetadata().get("user");
user = user == null ? "user" : user;
this.config.setUsername(user);
String password = server.getMetadata().get("password");
this.config.setPassword(password);
}
if (server.getMetadata().containsKey("configPath")) {
String path = server.getMetadata().get("configPath");
if (url.endsWith("/") && path.startsWith("/")) {
url = url.substring(0, url.length() - 1);
}
url = url + path;
}
this.config.setUri(url);
}
catch (Exception ex) {
if (config.isFailFast()) {
throw ex;
}
else {
logger.warn("Could not locate configserver via discovery", ex);
}
}
}
private String getHomePage(ServiceInstance server) {
return server.getUri().toString() + "/";
}
}
添加 DiscoveryClientConfigServiceConfiguration.java
/*
* Copyright 2013-2014 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.cloud.config.client;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.cloud.client.discovery.event.HeartbeatEvent;
import org.springframework.cloud.client.discovery.event.HeartbeatMonitor;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.event.ContextRefreshedEvent;
import org.springframework.context.event.EventListener;
import java.util.List;
/**
* 将HeartbeatEvent事件初始化后移.
* 从BootstrapConfiguration移动到EnableAutoConfiguration中
* @author superwen
*/
@ConditionalOnProperty(value = "spring.cloud.config.discovery.enabled", matchIfMissing = false)
@Configuration
public class DiscoveryClientConfigServiceConfiguration {
private static Log logger = LogFactory
.getLog(DiscoveryClientConfigServiceConfiguration.class);
@Autowired
private ConfigClientProperties config;
@Autowired
private DiscoveryClient discoveryClient;
private HeartbeatMonitor monitor = new HeartbeatMonitor();
// @EventListener(ContextRefreshedEvent.class)
// public void startup(ContextRefreshedEvent event) {
// refresh();
// }
@EventListener(HeartbeatEvent.class)
public void heartbeat(HeartbeatEvent event) {
if (monitor.update(event.getValue())) {
refresh();
}
}
private void refresh() {
try {
String serviceId = this.config.getDiscovery().getServiceId();
logger.debug("Locating configserver (" + serviceId + ") via discovery");
List<ServiceInstance> server = discoveryClient.getInstances(serviceId);
if (server.isEmpty()) {
throw new IllegalStateException(
"No instances found of configserver (" + serviceId + ")");
}
ServiceInstance instance = server.get(0);
logger.debug(
"Located configserver (" + serviceId + ") via discovery: " + instance);
String url = getHomePage(instance);
if (instance.getMetadata().containsKey("password")) {
String user = instance.getMetadata().get("user");
user = user == null ? "user" : user;
this.config.setUsername(user);
String password = instance.getMetadata().get("password");
this.config.setPassword(password);
}
if (instance.getMetadata().containsKey("configPath")) {
String path = instance.getMetadata().get("configPath");
if (url.endsWith("/") && path.startsWith("/")) {
url = url.substring(0, url.length() - 1);
}
url = url + path;
}
logger.debug("url=" + url);
this.config.setUri(url);
} catch (Exception ex) {
if (config.isFailFast()) {
throw ex;
} else {
logger.warn("Could not locate configserver via discovery", ex);
}
}
}
private String getHomePage(ServiceInstance server) {
return server.getUri().toString() + "/";
}
}
修改 spring.factories
# Auto Configure
org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
org.springframework.cloud.config.client.ConfigClientAutoConfiguration,\
org.springframework.cloud.config.client.DiscoveryClientConfigServiceConfiguration
# Bootstrap components
org.springframework.cloud.bootstrap.BootstrapConfiguration=\
org.springframework.cloud.config.client.ConfigServiceBootstrapConfiguration,\
org.springframework.cloud.config.client.DiscoveryClientConfigServiceBootstrapConfiguration
后置 HeartbeatEvent 事件,将其获取 config-server 的地址.改为从新的 eurekaclient 中获取即可.
