SpringCloud Gateway 动态路由

SpringCloud Gateway 路由配置变更的时候，如果不重启网关，是无法生效的，本文介绍如果在不重启网关的情况下，动态刷新路由配置。
一、解决路由无法删除的问题 【SpringCloud Gateway 动态路由】Spring Cloud Gateway 默认使用的基于内存为存储器的 InMemoryRouteDefinitionRepository，在GatewayAutoConfiguration中可以看到
@Bean@ConditionalOnMissingBean(RouteDefinitionRepository.class)public InMemoryRouteDefinitionRepository inMemoryRouteDefinitionRepository() { return new InMemoryRouteDefinitionRepository();} 在InMemoryRouteDefinitionRepository中我们可以看到，只有根据路由id去删除路由的操作。而要获取需要删除的路由的id，是比较复杂的。所以我们在路由变更的时候采用比较暴力的方式，即清空->重新加载。所以我们需要对InMemoryRouteDefinitionRepository进行改造。
基于此，我们重新定义了CustomInMemoryRouteDefinitionRepository 。代码如下：
import org.springframework.cloud.gateway.route.RouteDefinition;import org.springframework.cloud.gateway.route.RouteDefinitionRepository;import org.springframework.cloud.gateway.support.NotFoundException;import org.springframework.util.ObjectUtils;import reactor.core.publisher.Flux;import reactor.core.publisher.Mono;import java.util.LinkedHashMap;import java.util.Map;import static java.util.Collections.synchronizedMap;/** * @Author: Flex.Zang * @Date: 2022/3/28 15:44 * 解决无法删除路由的问题 */public class CustomInMemoryRouteDefinitionRepository implements RouteDefinitionRepository {private static final String DELETE = "delete";private final Map routes = synchronizedMap(new LinkedHashMap());@Overridepublic Mono save(Mono route) {return route.flatMap(r -> {if (ObjectUtils.isEmpty(r.getId())) {return Mono.error(new IllegalArgumentException("id may not be empty"));}routes.put(r.getId(), r);return Mono.empty();});}@Overridepublic Mono delete(Mono routeId) {return routeId.flatMap(id -> {if (DELETE.equals(id)) {routes.clear();return Mono.empty();}if (routes.containsKey(id)) {routes.remove(id);return Mono.empty();}return Mono.defer(() -> Mono.error(new NotFoundException("RouteDefinition not found: " + routeId)));});}@Overridepublic Flux getRouteDefinitions() {Map routesSafeCopy = new LinkedHashMap<>(routes);return Flux.fromIterable(routesSafeCopy.values());}} 并将默认的RouteDefinitionRepository替换成我们定义的CustomInMemoryRouteDefinitionRepository，代码如下
@Beanpublic RouteDefinitionRepository routeDefinitionRepository() {return new CustomInMemoryRouteDefinitionRepository();} 二、定义动态路由操作类此处内容较简单，直接上代码
import lombok.extern.slf4j.Slf4j;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.cloud.gateway.event.RefreshRoutesEvent;import org.springframework.cloud.gateway.route.RouteDefinition;import org.springframework.cloud.gateway.route.RouteDefinitionWriter;import org.springframework.context.ApplicationEventPublisher;import org.springframework.context.ApplicationEventPublisherAware;import org.springframework.stereotype.Component;import reactor.core.publisher.Mono;/** * @Author: Flex.Zang * @Date: 2022/3/28 13:38 */@Slf4j@Componentpublic class DynamicRouteService implements ApplicationEventPublisherAware {private final RouteDefinitionWriter routeDefinitionWriter;private ApplicationEventPublisher publisher;private static final String CONS_DELETE = "delete";@Autowiredpublic DynamicRouteService(RouteDefinitionWriter routeDefinitionWriter) {this.routeDefinitionWriter = routeDefinitionWriter;}@Overridepublic void setApplicationEventPublisher(ApplicationEventPublisher applicationEventPublisher) {this.publisher = applicationEventPublisher;}/*** 新增路由** @param definition* @return*/public String add(RouteDefinition definition) {try {routeDefinitionWriter.save(Mono.just(definition)).subscribe();this.publisher.publishEvent(new RefreshRoutesEvent(this));return "success";} catch (Exception e) {log.error(e.getMessage(), e);return "update route fail";}}/*** 更新路由** @param definition* @return*/public String update(RouteDefinition definition) {try {this.routeDefinitionWriter.delete(Mono.just(definition.getId())).subscribe();} catch (Exception e) {return "update fail,not find routerouteId: " + definition.getId();}try {routeDefinitionWriter.save(Mono.just(definition)).subscribe();this.publisher.publishEvent(new RefreshRoutesEvent(this));return "success";} catch (Exception e) {log.error(e.getMessage(), e);return "update route fail";}}/*** 清空路由** @return*/public String clear() {try {this.routeDefinitionWriter.delete(Mono.just(CONS_DELETE)).subscribe();this.publisher.publishEvent(new RefreshRoutesEvent(this));return "success";} catch (Exception e) {log.error(e.getMessage(), e);return "clear route fail";}}} 三、监听路由变更此处内容较简单，直接上代码
import org.springframework.boot.context.properties.ConfigurationProperties;import org.springframework.cloud.gateway.route.RouteDefinition;import org.springframework.stereotype.Component;import org.springframework.util.CollectionUtils;import javax.annotation.Resource;import java.util.List;/** * @Author: Flex.Zang * @Date: 2022/3/28 14:48 */@Component@ConfigurationProperties(prefix = "spring.cloud.gateway")public class GatewayConfig {private List routes;@Resourceprivate DynamicRouteService dynamicRouteService;public void setRoutes(List routes) {this.routes = routes;updateDefinition();}private void updateDefinition() {//清空路由dynamicRouteService.clear();if (!CollectionUtils.isEmpty(this.routes)) {//重新加载路由this.routes.forEach(definition -> {dynamicRouteService.add(definition);});}}} That's all, thank you!