springcloud gateway高级功能之集成apollo后动态刷新路由

springcloud集成apollo后动态刷新路由配置，官网给的demo如下

1import com.ctrip.framework.apollo.enums.PropertyChangeType;
2import com.ctrip.framework.apollo.model.ConfigChange;
3import com.ctrip.framework.apollo.model.ConfigChangeEvent;
4import com.ctrip.framework.apollo.spring.annotation.ApolloConfigChangeListener;
5import org.slf4j.Logger;
6import org.slf4j.LoggerFactory;
7import org.springframework.beans.BeansException;
8import org.springframework.beans.factory.annotation.Autowired;
9import org.springframework.cloud.context.environment.EnvironmentChangeEvent;
10import org.springframework.cloud.gateway.config.GatewayProperties;
11import org.springframework.cloud.gateway.event.RefreshRoutesEvent;
12import org.springframework.cloud.gateway.route.RouteDefinitionWriter;
13import org.springframework.context.ApplicationContext;
14import org.springframework.context.ApplicationContextAware;
15import org.springframework.context.ApplicationEventPublisher;
16import org.springframework.context.ApplicationEventPublisherAware;
17import org.springframework.context.annotation.Configuration;
18import org.springframework.stereotype.Component;
19
20import java.util.ArrayList;
21
22/**
23 * @author ksewen
24 * @date 2019/5/175:24 PM
25 */
26@Configuration
27public class GatewayPropertiesRefresher implements ApplicationContextAware,ApplicationEventPublisherAware {
28
29    private static final Logger logger = LoggerFactory.getLogger(GatewayPropertiesRefresher.class);
30
31    private static final String ID_PATTERN = "spring\\.cloud\\.gateway\\.routes\\[\\d+\\]\\.id";
32
33    private static final String DEFAULT_FILTER_PATTERN = "spring\\.cloud\\.gateway\\.default-filters\\[\\d+\\]\\.name";
34
35    private ApplicationContext applicationContext;
36
37    private ApplicationEventPublisher publisher;
38
39    @Autowired
40    private GatewayProperties gatewayProperties;
41
42    @Autowired
43    private RouteDefinitionWriter routeDefinitionWriter;
44
45    @Override
46    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
47        this.applicationContext = applicationContext;
48    }
49
50
51    @Override
52    public void setApplicationEventPublisher(ApplicationEventPublisher applicationEventPublisher) {
53        this.publisher = applicationEventPublisher;
54    }
55
56    @ApolloConfigChangeListener(interestedKeyPrefixes = "spring.cloud.gateway.",value="recommend-facade.yml")
57    public void onChange(ConfigChangeEvent changeEvent) {
58        refreshGatewayProperties(changeEvent);
59    }
60
61    /***
62     * 刷新org.springframework.cloud.gateway.config.PropertiesRouteDefinitionLocator中定义的routes
63     *
64     * @param changeEvent
65     * @return void
66     * @author ksewen
67     * @date 2019/5/21 2:13 PM
68     */
69    private void refreshGatewayProperties(ConfigChangeEvent changeEvent) {
70        logger.info("Refreshing GatewayProperties!");
71        preDestroyGatewayProperties(changeEvent);
72        this.applicationContext.publishEvent(new EnvironmentChangeEvent(changeEvent.changedKeys()));
73        refreshGatewayRouteDefinition();
74        logger.info("GatewayProperties refreshed!");
75    }
76
77    /***
78     * GatewayProperties没有@PreDestroy和destroy方法
79     * org.springframework.cloud.context.properties.ConfigurationPropertiesRebinder#rebind(java.lang.String)中destroyBean时不会销毁当前对象
80     * 如果把spring.cloud.gateway.前缀的配置项全部删除（例如需要动态删除最后一个路由的场景），initializeBean时也无法创建新的bean，则return当前bean
81     * 若仍保留有spring.cloud.gateway.routes[n]或spring.cloud.gateway.default-filters[n]等配置，initializeBean时会注入新的属性替换已有的bean
82     * 这个方法提供了类似@PreDestroy的操作，根据配置文件的实际情况把org.springframework.cloud.gateway.config.GatewayProperties#routes
83     * 和org.springframework.cloud.gateway.config.GatewayProperties#defaultFilters两个集合清空
84     *
85     * @param
86     * @return void
87     * @author ksewen
88     * @date 2019/5/21 2:13 PM
89     */
90    private synchronized void preDestroyGatewayProperties(ConfigChangeEvent changeEvent) {
91        logger.info("Pre Destroy GatewayProperties!");
92        final boolean needClearRoutes = this.checkNeedClear(changeEvent, ID_PATTERN, this.gatewayProperties.getRoutes().size());
93        if (needClearRoutes) {
94            this.gatewayProperties.setRoutes(new ArrayList<>());
95        }
96        final boolean needClearDefaultFilters = this.checkNeedClear(changeEvent, DEFAULT_FILTER_PATTERN, this.gatewayProperties.getDefaultFilters().size());
97        if (needClearDefaultFilters) {
98            this.gatewayProperties.setRoutes(new ArrayList<>());
99        }
100        logger.info("Pre Destroy GatewayProperties finished!");
101    }
102
103    private void refreshGatewayRouteDefinition() {
104        logger.info("Refreshing Gateway RouteDefinition!");
105        this.publisher.publishEvent(new RefreshRoutesEvent(this));
106        logger.info("Gateway RouteDefinition refreshed!");
107    }
108
109    /***
110     * 根据changeEvent和定义的pattern匹配key，如果所有对应PropertyChangeType为DELETED则需要清空GatewayProperties里相关集合
111     *
112     * @param changeEvent
113     * @param pattern
114     * @param existSize
115     * @return boolean
116     * @author ksewen
117     * @date 2019/5/23 2:18 PM
118     */
119    private boolean checkNeedClear(ConfigChangeEvent changeEvent, String pattern, int existSize) {
120
121        return changeEvent.changedKeys().stream().filter(key -> key.matches(pattern))
122                .filter(key -> {
123                    ConfigChange change = changeEvent.getChange(key);
124                    return PropertyChangeType.DELETED.equals(change.getChangeType());
125                }).count() == existSize;
126    }
127
128}

这里有个坑，如果是没有用到默认的application.properties,这里我们就需要填写namespace了，如下，需要配置value="使用的namespace"

1    @ApolloConfigChangeListener(interestedKeyPrefixes = "spring.cloud.gateway.",value="xxxx.yml")
2    public void onChange(ConfigChangeEvent changeEvent) {
3        refreshGatewayProperties(changeEvent);
4    }