网关动态路由原理

pclin
14
2025-01-09


Spring Cloud Gateway 数据库存储路由信息的扩展方案

#Spring Cloud Gateway 路由加载源码

  1. DispatcherHandler 接管用户请求

  2. RoutePredicateHandlerMapping 路由匹配

    1. 根据 RouteLocator 获取 RouteDefinitionLocator

    2. 返回多个 RouteDefinitionLocator.getRouteDefinitions()的路由定义信息

  3. FilteringWebHandler 执行路由定义中的 filter 最后路由到具体的业务服务中

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#Spring Cloud Gateway 默认动态路由实现

GatewayControllerEndpoint 基于 actuate 端点的默认实现,支持 JVM 级别的动态路由,不能序列化存储

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// 上图动态路由的信息保存的默认实现是基于内存的实现
public class InMemoryRouteDefinitionRepository implements RouteDefinitionRepository {
	private final Map<String, RouteDefinition> routes = synchronizedMap(new LinkedHashMap<String, RouteDefinition>());
	@Override
	public Mono<Void> save(Mono<RouteDefinition> route){}
	@Override
	public Mono<Void> delete(Mono<String> routeId){}

	@Override
	public Flux<RouteDefinition> getRouteDefinitions(){}
}

#扩展基于 Mysql + Redis 存储分布式动态组件

#为什么使用 Mysql 的同时,又要使用 Redis?

  1. spring cloud gateway 基于 webflux 背压,暂时不支持 mysql 数据库

  2. Redis-reactive 支持 spring cloudgateway 的背压,同时还可以实现分布式,高性能

    #扩展思路

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  1. 增加一个路由管理模块,参考 GatewayControllerEndpoint 实现,启动时加载数据库中配置文件到 Redis

  2. 网关模块重写 RouteDefinitionRepository,getRouteDefinitions()取 Redis 中读取即可实现

  3. 前端配合 json-view 类似插件,直接修改展示。

#具体实现

  • 路由管理模块核心处理逻辑,获取路由和更新路由

/**
 * @author lengleng
 * @date 2018年11月06日10:27:55
 * <p>
 * 动态路由处理类
 */
@Slf4j
@AllArgsConstructor
@Service("sysRouteConfService")
public class SysRouteConfServiceImpl extends ServiceImpl<SysRouteConfMapper, SysRouteConf> implements SysRouteConfService {
	private final RedisTemplate redisTemplate;
	private final ApplicationEventPublisher applicationEventPublisher;

	/**
	 * 获取全部路由
	 * <p>
	 * RedisRouteDefinitionWriter.java
	 * PropertiesRouteDefinitionLocator.java
	 *
	 * @return
	 */
	@Override
	public List<SysRouteConf> routes() {
		SysRouteConf condition = new SysRouteConf();
		condition.setDelFlag(CommonConstant.STATUS_NORMAL);
		return baseMapper.selectList(new EntityWrapper<>(condition));
	}

	/**
	 * 更新路由信息
	 *
	 * @param routes 路由信息
	 * @return
	 */
	@Override
	public Mono<Void> editRoutes(JSONArray routes) {
		// 清空Redis 缓存
		Boolean result = redisTemplate.delete(CommonConstant.ROUTE_KEY);
		log.info("清空网关路由 {} ", result);

		// 遍历修改的routes,保存到Redis
		List<RouteDefinitionVo> routeDefinitionVoList = new ArrayList<>();
		routes.forEach(value -> {
			log.info("更新路由 ->{}", value);
			RouteDefinitionVo vo = new RouteDefinitionVo();
			Map<String, Object> map = (Map) value;

			Object id = map.get("routeId");
			if (id != null) {
				vo.setId(String.valueOf(id));
			}

			Object predicates = map.get("predicates");
			if (predicates != null) {
				JSONArray predicatesArray = (JSONArray) predicates;
				List<PredicateDefinition> predicateDefinitionList =
					predicatesArray.toList(PredicateDefinition.class);
				vo.setPredicates(predicateDefinitionList);
			}

			Object filters = map.get("filters");
			if (filters != null) {
				JSONArray filtersArray = (JSONArray) filters;
				List<FilterDefinition> filterDefinitionList
					= filtersArray.toList(FilterDefinition.class);
				vo.setFilters(filterDefinitionList);
			}

			Object uri = map.get("uri");
			if (uri != null) {
				vo.setUri(URI.create(String.valueOf(uri)));
			}

			Object order = map.get("order");
			if (order != null) {
				vo.setOrder(Integer.parseInt(String.valueOf(order)));
			}

			redisTemplate.setHashValueSerializer(new Jackson2JsonRedisSerializer<>(RouteDefinitionVo.class));
			redisTemplate.opsForHash().put(CommonConstant.ROUTE_KEY, vo.getId(), vo);
			routeDefinitionVoList.add(vo);
		});

		// 逻辑删除全部
		SysRouteConf condition = new SysRouteConf();
		condition.setDelFlag(CommonConstant.STATUS_NORMAL);
		this.delete(new EntityWrapper<>(condition));

		//插入生效路由
		List<SysRouteConf> routeConfList = routeDefinitionVoList.stream().map(vo -> {
			SysRouteConf routeConf = new SysRouteConf();
			routeConf.setRouteId(vo.getId());
			routeConf.setFilters(JSONUtil.toJsonStr(vo.getFilters()));
			routeConf.setPredicates(JSONUtil.toJsonStr(vo.getPredicates()));
			routeConf.setOrder(vo.getOrder());
			routeConf.setUri(vo.getUri().toString());
			return routeConf;
		}).collect(Collectors.toList());
		this.insertBatch(routeConfList);
		log.debug("更新网关路由结束 ");

		this.applicationEventPublisher.publishEvent(new RefreshRoutesEvent(this));
		return Mono.empty();
	}
}

  • 网关自定义 RedisRouteDefinitionRepository

    /**
     * @author lengleng
     * @date 2018/10/31
     * <p>
     * redis 保存路由信息,优先级比配置文件高
     */
    @Slf4j
    @Component
    @AllArgsConstructor
    public class RedisRouteDefinitionWriter implements RouteDefinitionRepository {
    	private final RedisTemplate redisTemplate;
    
    	@Override
    	public Mono<Void> save(Mono<RouteDefinition> route) {
    		return route.flatMap(r -> {
    			RouteDefinitionVo vo = new RouteDefinitionVo();
    			BeanUtils.copyProperties(r, vo);
    			log.info("保存路由信息{}", vo);
    			redisTemplate.opsForHash().put(CommonConstant.ROUTE_KEY, r.getId(), vo);
    			return Mono.empty();
    		});
    	}
    	@Override
    	public Mono<Void> delete(Mono<String> routeId) {
    		routeId.subscribe(id -> {
    			log.info("删除路由信息{}", id);
    			redisTemplate.opsForHash().delete(CommonConstant.ROUTE_KEY, id);
    		});
    		return Mono.empty();
    	}
    
    	/**
    	 * 动态路由入口
    	 *
    	 * @return
    	 */
    	@Override
    	public Flux<RouteDefinition> getRouteDefinitions() {
    		redisTemplate.setHashValueSerializer(new Jackson2JsonRedisSerializer<>(RouteDefinitionVo.class));
    		List<RouteDefinitionVo> values = redisTemplate.opsForHash().values(CommonConstant.ROUTE_KEY);
    		List<RouteDefinition> definitionList = new ArrayList<>();
    		values.forEach(vo -> {
    			RouteDefinition routeDefinition = new RouteDefinition();
    			BeanUtils.copyProperties(vo, routeDefinition);
    			definitionList.add(vo);
    		});
    		log.debug("redis 中路由定义条数: {}, {}", definitionList.size(), definitionList);
    		return Flux.fromIterable(definitionList);
    	}
    }
    

  • 3.库表定义

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动物装饰