前言

spring cloud gateway默认为内存存储策略，通过配置文件加载的方式生成路由定义信息

可以看到，RouteDefinitionRepository继承了两个父接口，分别为RouteDefinitionLocator和RouteDefinitionWriter，RouteDefinitionLocator定义了路由定义获取接口，而RouteDefinitionWriter则定义了路由定义保存更新save接口和删除接口。

可以看到RouteDefinitionRepository是核心接口，其默认的实现类有上图两个，分别是基于内存和基于redis的，如果需要redis实现动态路由则只需要实现RouteDefinitionRepository接口并注入bean即可

一、实现RouteDefinitionRepository接口

这里其实spring cloud gateway已经有默认实现了的基于redis 的路由定义相关的repository，但由于其并没有做本地缓存，是纯redis的方式读取写入，这样会导致在进行路由调用的时候频繁的调用其getRouteDefinitions方法，频繁的读取redis其实也是有一定的性能损耗，因此我们其实稍加利用，添加本地缓存即可(本示例使用咖啡因缓存)，注意添加注解:@EnableCaching

/*** @classDesc:* @author: cyjer* @date: 2023/1/30 9:53*/
@Component
@Slf4j
public class RedisRouteRepository implements RouteDefinitionRepository {private static final String ROUTE_DEFINITION_REDIS_KEY_PREFIX_QUERY = "routeDefinition::";private final ReactiveRedisTemplate<String, RouteDefinition> reactiveRedisTemplate;private final ReactiveValueOperations<String, RouteDefinition> routeDefinitionReactiveValueOperations;public RedisRouteRepository(ReactiveRedisTemplate<String, RouteDefinition> reactiveRedisTemplate) {this.reactiveRedisTemplate = reactiveRedisTemplate;this.routeDefinitionReactiveValueOperations = reactiveRedisTemplate.opsForValue();}@Override@Cacheable(cacheNames = "redisRoute")public Flux<RouteDefinition> getRouteDefinitions() {log.info("<<<<<<<<<<获取路由信息>>>>>>>>>>");return this.reactiveRedisTemplate.keys(this.createKey("*")).flatMap((key) -> {return this.reactiveRedisTemplate.opsForValue().get(key);}).onErrorContinue((throwable, routeDefinition) -> {if (log.isErrorEnabled()) {log.error("get routes from redis error cause : {}", throwable.toString(), throwable);}});}@Override@CacheEvict(cacheNames = "redisRoute")public Mono<Void> save(Mono<RouteDefinition> route) {log.info("<<<<<<<<<<保存路由信息>>>>>>>>>>");return route.flatMap((routeDefinition) -> {return this.routeDefinitionReactiveValueOperations.set(this.createKey(routeDefinition.getId()), routeDefinition).flatMap((success) -> {return success ? Mono.empty() : Mono.defer(() -> {return Mono.error(new RuntimeException(String.format("Could not add route to redis repository: %s", routeDefinition)));});});});}@Override@CacheEvict(cacheNames = "redisRoute")public Mono<Void> delete(Mono<String> routeId) {log.info("<<<<<<<<<<删除路由信息>>>>>>>>>>");return routeId.flatMap((id) -> {return this.routeDefinitionReactiveValueOperations.delete(this.createKey(id)).flatMap((success) -> {return success ? Mono.empty() : Mono.defer(() -> {return Mono.error(new NotFoundException(String.format("Could not remove route from redis repository with id: %s", routeId)));});});});}private String createKey(String routeId) {return ROUTE_DEFINITION_REDIS_KEY_PREFIX_QUERY + routeId;}}

/*** @classDesc: 本地缓存* @author: cyjer* @date: 2023/1/30 9:53*/
@Configuration
public class CaffeineConfig {@Bean@Primarypublic CacheManager caffeineCacheManager() {SimpleCacheManager cacheManager = new SimpleCacheManager();List<CaffeineCache> caches = new ArrayList<>();Map<String, Object> map = getCacheType();for (String name : map.keySet()) {caches.add(new CaffeineCache(name, (Cache<Object, Object>) map.get(name)));}cacheManager.setCaches(caches);return cacheManager;}/*** 初始化自定义缓存策略** @return*/private static Map<String, Object> getCacheType() {Map<String, Object> map = new ConcurrentHashMap<>();map.put("redisRoute", Caffeine.newBuilder().build());return map;}
}

到此其实基于redis的路由仓储service已经结束

基于zookeeper注册中心实现项目自动上报路由

为了实现动态路由，其实可以采用提供暴露接口的方式把相应的仓储接口提供出来，本示例提供的只是使用zk的监听机制，实现动态路由

关于zk的事件监听可以查看我的这篇文章:zookeeper相关操作

1、网关启动时添加zk监听事件

@Component
@Slf4j
@RequiredArgsConstructor
public class GatewayApplication implements ApplicationListener<ContextRefreshedEvent> {private final RouteDefinitionService routeDefinitionService;private final ZookeeperService zookeeperService;private final RouteProcesser routeProcesser;@Overridepublic void onApplicationEvent(ContextRefreshedEvent event) {//拉取网关配置routeDefinitionService.refreshRouteDefinition();log.info("<<<<<<<<<<刷新网关配置完成>>>>>>>>>>");zookeeperService.create(Constraint.ROUTE_DEFINITION, "init");zookeeperService.addWatchChildListener(Constraint.ROUTE_DEFINITION, routeProcesser);log.info("<<<<<<<<<<动态路由监听器配置完成>>>>>>>>>>");}
}

2、发布刷新事件:

    public void refreshRouteDefinition() {this.applicationEventPublisher.publishEvent(new RefreshRoutesEvent(this));redisRouteRepository.getRouteDefinitions();}

3、 监听处理

/*** @classDesc: * @author: cyjer* @date: 2023/2/10 11:13*/
@Slf4j
@Component
@RequiredArgsConstructor
public class RouteProcesser extends AbstractChildListenerProcess implements ApiDefinitionConstraint {private static final String JTR = "/";private final static String ROUTE_CONFIG_ARGS_PREFIX = "_genkey_";private final RedisRouteRepository redisRouteRepository;private final RouteDefinitionService routeDefinitionService;@Overridepublic void process(CuratorFramework curatorFramework, PathChildrenCacheEvent cacheEvent) {ChildData data = cacheEvent.getData();if (Objects.nonNull(data) && cacheEvent.getType().equals(PathChildrenCacheEvent.Type.CHILD_UPDATED)) {log.info("<<<<<<<<<<监听到动态路由变动申请>>>>>>>>>>");String content = new String(data.getData(), StandardCharsets.UTF_8);SiriusRouteDefinition siriusRouteDefinition = JSONObject.parseObject(content, SiriusRouteDefinition.class);RouteDefinition routeDefinition = new RouteDefinition();String serviceId = siriusRouteDefinition.getServiceId();routeDefinition.setId(serviceId);URI routeUri = UriComponentsBuilder.fromUriString("lb://" + serviceId).build().toUri();routeDefinition.setUri(routeUri);List<PredicateDefinition> predicates = getPredicates(JTR + serviceId + "/**");if (!predicates.isEmpty()) {routeDefinition.setPredicates(predicates);}// 获取过滤器List<FilterDefinition> filters = new ArrayList<>();Map<String, String> args = new LinkedHashMap<>();args.put(ROUTE_CONFIG_ARGS_PREFIX, "1");FilterDefinition filterDefinition = new FilterDefinition();filterDefinition.setName("StripPrefix");filterDefinition.setArgs(args);filters.add(filterDefinition);routeDefinition.setFilters(filters);redisRouteRepository.save(Mono.just(routeDefinition)).subscribe();routeDefinitionService.refreshRouteDefinition();log.info("<<<<<<<<<<刷新网关路由成功>>>>>>>>>>");}}/*** 获取地址断言** @param routePaths 路由地址* @return java.util.List*/private List<PredicateDefinition> getPredicates(String routePaths) {Map<String, String> args = new HashMap<>();String[] paths = routePaths.split(",");for (int i = 0; i < paths.length; i++) {args.put(ROUTE_CONFIG_ARGS_PREFIX + i, paths[i]);}PredicateDefinition predicate = new PredicateDefinition();predicate.setName("Path");predicate.setArgs(args);List<PredicateDefinition> predicates = new ArrayList<>();predicates.add(predicate);return predicates;}}

4、非网关的其他项目启动时注册路由

/*** @classDesc: 注册应用路由信息* @author: cyjer* @date: 2023/2/11 20:47*/
@Component
@Order(2)
@RequiredArgsConstructor
@Slf4j
public class ServiceRouteDefinitionReporter implements CommandLineRunner, Constraint {private final GatewayServiceProperties gatewayServiceProperties;private final ZookeeperService zookeeperService;@Overridepublic void run(String... args) throws Exception {String applicationName = apiDefinitionReporter.getApplicationName();siriusRouteDefinition.setServiceId(applicationName);siriusRouteDefinition.setGatewayId(gatewayServiceProperties.getGatewayId());zookeeperService.create(ROUTE_DEFINITION + SPLIT + applicationName, JSONObject.toJSONString(siriusRouteDefinition));zookeeperService.update(ROUTE_DEFINITION + SPLIT + applicationName, JSONObject.toJSONString(siriusRouteDefinition));log.info("<<<<< successfully reported route information >>>>>");}}