Spring Cloud Gateway 数据库存储路由信息的扩展方案

动态路由背景

无论你在使用Zuul还是Spring Cloud Gateway 的时候，官方文档提供的方案总是基于配置文件配置的方式

例如：

  # zuul 的配置形式
  routes:
    pig-auth:
      path: /auth/**
      serviceId: pig-auth
      stripPrefix: true
  # gateway 的配置形式
  routes:
  - id: pigx-auth
  	uri: lb://pigx-auth
    predicates:
    - Path=/auth/**
    filters:
    - ValidateCodeGatewayFilter

配置更改需要重启服务，不能满足实际生产过程中的动态刷新、实时变更的业务需求。

基于以上分析 **pig**已经提供了基于Zuul版本的动态路由功能，附[Git 地址传送门](https://gitee.com/log4j/pig),效果如下图可以实时配置修改刷新。

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

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

// 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

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

1. 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(); } }
2. 网关自定义RedisRouteDefinitionRepository

@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();

}

@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

转自：https://cloud.tencent.com/developer/article/1361901