前言
apollo配置经常使用的方式是@value，比较便捷，如果只出现在一个类中还行，但是如果多个类中并不是很方便，特别是如果出现配置值变化了之后需要触发相关变动也无法实现，因此就会考虑使用配置类@ConfigurationProperties，它能实现：
- 统一管理一组配置。
- 配置变化的时需要触发相关变动只涉及一个bean。
但是apollo配置变化时不会把@ConfigurationProperties的值进行更新，具体看官方文档，需要配合EnvironmentChangeEvent或RefreshScope使用。
可以大概看看：
package com.ctrip.framework.apollo.use.cases.spring.cloud.zuul;
import com.ctrip.framework.apollo.model.ConfigChangeEvent;
import com.ctrip.framework.apollo.spring.annotation.ApolloConfigChangeListener;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.context.environment.EnvironmentChangeEvent;
import org.springframework.cloud.netflix.zuul.RoutesRefreshedEvent;
import org.springframework.cloud.netflix.zuul.filters.RouteLocator;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;
@Component
public class ZuulPropertiesRefresher implements ApplicationContextAware {
private static final Logger logger = LoggerFactory.getLogger(ZuulPropertiesRefresher.class);
private ApplicationContext applicationContext;
@Autowired
private RouteLocator routeLocator;
@ApolloConfigChangeListener(interestedKeyPrefixes = "zuul.")
public void onChange(ConfigChangeEvent changeEvent) {
refreshZuulProperties(changeEvent);
}
private void refreshZuulProperties(ConfigChangeEvent changeEvent) {
logger.info("Refreshing zuul properties!");
this.applicationContext.publishEvent(new EnvironmentChangeEvent(changeEvent.changedKeys()));
this.applicationContext.publishEvent(new RoutesRefreshedEvent(routeLocator));
logger.info("Zuul properties refreshed!");
}
@Override
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
this.applicationContext = applicationContext;
}
}
使用@ApolloConfigChangeListener注册了apollo配置变化监听器，内部使用了cloud发布EnvironmentChangeEvent事件进行更新。
package com.apolloconfig.apollo.demo.springboot.refresh;
import com.apolloconfig.apollo.demo.springboot.config.SampleRedisConfig;
import com.ctrip.framework.apollo.core.ConfigConsts;
import com.ctrip.framework.apollo.model.ConfigChangeEvent;
import com.ctrip.framework.apollo.spring.annotation.ApolloConfigChangeListener;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.cloud.context.scope.refresh.RefreshScope;
import org.springframework.stereotype.Component;
@ConditionalOnProperty("redis.cache.enabled")
@Component
public class SpringBootApolloRefreshConfig {
private static final Logger logger = LoggerFactory.getLogger(SpringBootApolloRefreshConfig.class);
private final SampleRedisConfig sampleRedisConfig;
private final RefreshScope refreshScope;
public SpringBootApolloRefreshConfig(
final SampleRedisConfig sampleRedisConfig,
final RefreshScope refreshScope) {
this.sampleRedisConfig = sampleRedisConfig;
this.refreshScope = refreshScope;
}
@ApolloConfigChangeListener(value = "${listeners}", interestedKeyPrefixes = {"redis.cache."})
public void onChange(ConfigChangeEvent changeEvent) {
logger.info("before refresh {}", sampleRedisConfig.toString());
refreshScope.refresh("sampleRedisConfig");
logger.info("after refresh {}", sampleRedisConfig);
}
}
package com.apolloconfig.apollo.demo.springboot.config;
import com.google.common.collect.Lists;
import com.google.common.collect.Maps;
import java.util.List;
import java.util.Map;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.cloud.context.config.annotation.RefreshScope;
import org.springframework.stereotype.Component;
@ConditionalOnProperty("redis.cache.enabled")
@ConfigurationProperties(prefix = "redis.cache")
@Component("sampleRedisConfig")
@RefreshScope
public class SampleRedisConfig implements InitializingBean {
private static final Logger logger = LoggerFactory.getLogger(SampleRedisConfig.class);
private int expireSeconds;
private String clusterNodes;
private int commandTimeout;
private Map<String, String> someMap = Maps.newLinkedHashMap();
private List<String> someList = Lists.newLinkedList();
@Override
public void afterPropertiesSet() throws Exception {
logger.info(
"SampleRedisConfig initialized - expireSeconds: {}, clusterNodes: {}, commandTimeout: {}, someMap: {}, someList: {}",
expireSeconds, clusterNodes, commandTimeout, someMap, someList);
}
public void setExpireSeconds(int expireSeconds) {
this.expireSeconds = expireSeconds;
}
public void setClusterNodes(String clusterNodes) {
this.clusterNodes = clusterNodes;
}
public void setCommandTimeout(int commandTimeout) {
this.commandTimeout = commandTimeout;
}
public Map<String, String> getSomeMap() {
return someMap;
}
public List<String> getSomeList() {
return someList;
}
@Override
public String toString() {
return String.format(
"[SampleRedisConfig] expireSeconds: %d, clusterNodes: %s, commandTimeout: %d, someMap: %s, someList: %s",
expireSeconds, clusterNodes, commandTimeout, someMap, someList);
}
}
使用了RefreshScope进行刷新配置(重新create bean)，但是不够高效，最理想的事一个值发生变化只要重新把对应的属性set即可。
那么我们下面尝试下，需要解决问题：
- 确定@ApolloConfigChangeListener.value能不能填
*表示匹配所有namespace。 - 根据ConfigChangeEvent找到配置类及对应的成员进行set。
解决@ApolloConfigChangeListener监听所有namespace
@ApolloConfigChangeListener(value = "*")
public void onChange(ConfigChangeEvent changeEvent) {
log.info("onChange changeEvent:{}", changeEvent);
}
发现并不行。应该可以编程式添加listener
编程式添加listener
找到官方文档：
Config config = ConfigService.getAppConfig();
config.addChangeListener(new ConfigChangeListener() {
@Override
public void onChange(ConfigChangeEvent changeEvent) {
for (String key : changeEvent.changedKeys()) {
ConfigChange change = changeEvent.getChange(key);
System.out.println(String.format(
"Found change - key: %s, oldValue: %s, newValue: %s, changeType: %s",
change.getPropertyName(), change.getOldValue(),
change.getNewValue(), change.getChangeType()));
}
}
});
ConfigService.getAppConfig()默认监听applicationnamespace，我们需要只监听项目依赖的的namespace。
获取项目依赖的的namespace
google了一下发现：apollo配置中心之--spring boot如何加载apollo。 可以通过environment获取key为ApolloPropertySources，我们尝试下：
@PostConstruct
public void registerApolloConfigChangeListener() {
//从env中拿到所有已从Apollo加载的propertySource,获取监听的nameSpace
CompositePropertySource apolloPropertySources = (CompositePropertySource) configurableEnvironment.getPropertySources().get("ApolloPropertySources");
if (Objects.isNull(apolloPropertySources)) {
return;
}
Collection<PropertySource<?>> propertySourceList = apolloPropertySources.getPropertySources();
//注册监听所有加载的nameSpace
propertySourceList.forEach(propertySource -> {
ConfigChangeListener configChangeListener = changeEvent -> {
for (String changedKey : changeEvent.changedKeys()) {
ConfigChange change = changeEvent.getChange(changedKey);
System.out.println(String.format(
"Found change - key: %s, oldValue: %s, newValue: %s, changeType: %s",
change.getPropertyName(), change.getOldValue(),
change.getNewValue(), change.getChangeType()));
}
};
Config config = ConfigService.getConfig(propertySource.getName());
config.addChangeListener(configChangeListener);
});
}
寻找根据ConfigChangeEvent找到配置类及对应的成员进行set的方式
google了一下，没找到，但是spring肯定有相关的实现，比如读取yml后对 @ConfigurationProperties属性进行填充，通过这篇文章找到ConfigurationPropertiesBindingPostProcessor是核心处理类：
通过ConfigurationPropertiesBindingPostProcessor#postProcessBeforeInitialization进行赋值，下面我们来看看能不能直接使用它：
package com.onepiece.apollo;
import com.ctrip.framework.apollo.Config;
import com.ctrip.framework.apollo.ConfigChangeListener;
import com.ctrip.framework.apollo.ConfigService;
import com.google.common.collect.Maps;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang.StringUtils;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanPostProcessor;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.context.properties.ConfigurationPropertiesBindingPostProcessor;
import org.springframework.context.ApplicationContext;
import org.springframework.core.Ordered;
import org.springframework.core.env.CompositePropertySource;
import org.springframework.core.env.ConfigurableEnvironment;
import org.springframework.core.env.PropertySource;
import org.springframework.stereotype.Component;
import javax.annotation.PostConstruct;
import javax.annotation.Resource;
import java.util.Collection;
import java.util.Comparator;
import java.util.Map;
import java.util.Objects;
import java.util.Optional;
@Slf4j
@Component
public class ApolloRefreshConfig implements BeanPostProcessor, Ordered {
@Resource
private ConfigurableEnvironment configurableEnvironment;
private Map<String, String> configPrefixBeanNameMapping;
@Resource
private ConfigurationPropertiesBindingPostProcessor configurationPropertiesBindingPostProcessor;
@Resource
private ApplicationContext applicationContext;
@PostConstruct
public void registerApolloConfigChangeListener() {
//从env中拿到所有已从Apollo加载的propertySource,获取监听的nameSpace
CompositePropertySource apolloPropertySources = (CompositePropertySource) configurableEnvironment.getPropertySources().get("ApolloPropertySources");
if (Objects.isNull(apolloPropertySources)) {
return;
}
Collection<PropertySource<?>> propertySourceList = apolloPropertySources.getPropertySources();
//注册监听所有加载的nameSpace
propertySourceList.forEach(propertySource -> {
ConfigChangeListener configChangeListener = changeEvent -> {
for (String changedKey : changeEvent.changedKeys()) {
log.info("apollo changed namespace:{} Key:{} value:{}", changeEvent.getNamespace(), changedKey, changeEvent.getChange(changedKey));
String beanName = getBeanName(changedKey);
configurationPropertiesBindingPostProcessor.postProcessBeforeInitialization(applicationContext.getBean(beanName), beanName);
}
};
Config config = ConfigService.getConfig(propertySource.getName());
config.addChangeListener(configChangeListener);
});
}
@Override
public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {
ConfigurationProperties propertiesAnno = bean.getClass().getAnnotation(ConfigurationProperties.class);
if (propertiesAnno != null) {
if (configPrefixBeanNameMapping == null) {
configPrefixBeanNameMapping = Maps.newHashMap();
}
String prefix = propertiesAnno.prefix() != null ? propertiesAnno.prefix() : propertiesAnno.value() == null ? null : propertiesAnno.value();
if (StringUtils.isNotBlank(prefix) && StringUtils.isNotBlank(beanName)) {
this.configPrefixBeanNameMapping.put(prefix, beanName);
}
}
return bean;
}
@Override
public int getOrder() {
return 0;
}
private String getBeanName(String key) {
if (configPrefixBeanNameMapping != null) {
Optional<Map.Entry<String, String>> bestMatchEntry = configPrefixBeanNameMapping.entrySet().stream()
.filter(entryt -> key.startsWith(entryt.getKey() + "."))
.max(Comparator.comparing(Map.Entry<String, String>::getKey));
return bestMatchEntry.map(Map.Entry::getValue).orElse(null);
}
return null;
}
}以上就是apollo更改配置刷新@ConfigurationProperties配置类的详细内容，更多关于apollo刷新@ConfigurationProperties的资料请关注编程网其它相关文章！
