基于Redis实现Springcloud Gateway动态路由

古城微笑少年丶 2022-12-22 14:28 206阅读 0赞

## 1. 将 actuator 端点暴露出来 ##

management:
      endpoints:
        web:
          exposure:
            include: "*"

## 2. redis 配置 ##

[https://www.cnblogs.com/idea360/p/12632801.html][https_www.cnblogs.com_idea360_p_12632801.html]

## 3. 将原内存路由持久化到 redis ##

@Component
    public class RedisRouteDefinitionRepository implements RouteDefinitionRepository {
    
        /**
         * hash存储的key
         */
        public static final String GATEWAY_ROUTES = "gateway_dynamic_route";
    
        @Resource
        private StringRedisTemplate redisTemplate;
    
        /**
         * 获取路由信息
         * @return
         */
        @Override
        public Flux<RouteDefinition> getRouteDefinitions() {
            List<RouteDefinition> routeDefinitions = new ArrayList<>();
            redisTemplate.opsForHash().values(GATEWAY_ROUTES).stream()
                    .forEach(routeDefinition -> routeDefinitions.add(JSON.parseObject(routeDefinition.toString(), RouteDefinition.class)));
            return Flux.fromIterable(routeDefinitions);
        }
    
        @Override
        public Mono<Void> save(Mono<RouteDefinition> route) {
            return route.flatMap(routeDefinition -> {
                redisTemplate.opsForHash().put(GATEWAY_ROUTES, routeDefinition.getId(), JSONObject.toJSONString(routeDefinition));
                return Mono.empty();
            });
        }
    
        @Override
        public Mono<Void> delete(Mono<String> routeId) {
            return routeId.flatMap(id -> {
                if (redisTemplate.opsForHash().hasKey(GATEWAY_ROUTES, id)) {
                    redisTemplate.opsForHash().delete(GATEWAY_ROUTES, id);
                    return Mono.empty();
                }
                return Mono.defer(() -> Mono.error(new NotFoundException("route definition is not found, routeId:" + routeId)));
            });
        }
    
    }

## 4. 重写动态路由服务 ##

@Service
    public class GatewayDynamicRouteService implements ApplicationEventPublisherAware {
    
        @Resource
        private RedisRouteDefinitionRepository redisRouteDefinitionRepository;
    
        private ApplicationEventPublisher applicationEventPublisher;
    
        /**
         * 增加路由
         * @param routeDefinition
         * @return
         */
        public int add(RouteDefinition routeDefinition) {
            redisRouteDefinitionRepository.save(Mono.just(routeDefinition)).subscribe();
            applicationEventPublisher.publishEvent(new RefreshRoutesEvent(this));
            return 1;
        }
    
        /**
         * 更新
         * @param routeDefinition
         * @return
         */
        public int update(RouteDefinition routeDefinition) {
            redisRouteDefinitionRepository.delete(Mono.just(routeDefinition.getId()));
            redisRouteDefinitionRepository.save(Mono.just(routeDefinition)).subscribe();
            applicationEventPublisher.publishEvent(new RefreshRoutesEvent(this));
            return 1;
        }
    
        /**
         * 删除
         * @param id
         * @return
         */
        public Mono<ResponseEntity<Object>> delete(String id) {
            return redisRouteDefinitionRepository.delete(Mono.just(id)).then(Mono.defer(() -> Mono.just(ResponseEntity.ok().build())))
                    .onErrorResume(t -> t instanceof NotFoundException, t -> Mono.just(ResponseEntity.notFound().build()));
        }
    
    
        @Override
        public void setApplicationEventPublisher(ApplicationEventPublisher applicationEventPublisher) {
            this.applicationEventPublisher = applicationEventPublisher;
        }
    }

## 5. 对外暴露接口 ##

@RestController
    @RequestMapping("/gateway")
    public class GatewayDynamicRouteController {
    
        @Resource
        private GatewayDynamicRouteService gatewayDynamicRouteService;
    
        @PostMapping("/add")
        public String create(@RequestBody RouteDefinition entity) {
            int result = gatewayDynamicRouteService.add(entity);
            return String.valueOf(result);
        }
    
        @PostMapping("/update")
        public String update(@RequestBody RouteDefinition entity) {
            int result = gatewayDynamicRouteService.update(entity);
            return String.valueOf(result);
        }
    
        @DeleteMapping("/delete/{id}")
        public Mono<ResponseEntity<Object>> delete(@PathVariable String id) {
            return gatewayDynamicRouteService.delete(id);
        }
    
    }

# 测试 #

测试前删除我们配置的静态路由，因为静态路由和 redis 动态路由同时存在时取并集。

1.  访问 [http://localhost:2000/actuator/gateway/routes][http_localhost_2000_actuator_gateway_routes] , 可以看到只有默认路由。

[
        {
            "route_id": "CompositeDiscoveryClient_consul",
            "route_definition": {
                "id": "CompositeDiscoveryClient_consul",
                "predicates": [
                    {
                        "name": "Path",
                        "args": {
                            "pattern": "/consul/**"
                        }
                    }
                ],
                "filters": [
                    {
                        "name": "RewritePath",
                        "args": {
                            "regexp": "/consul/(?<remaining>.*)",
                            "replacement": "/${remaining}"
                        }
                    }
                ],
                "uri": "lb://consul",
                "order": 0
            },
            "order": 0
        },
        {
            "route_id": "CompositeDiscoveryClient_idc-gateway",
            "route_definition": {
                "id": "CompositeDiscoveryClient_idc-gateway",
                "predicates": [
                    {
                        "name": "Path",
                        "args": {
                            "pattern": "/idc-gateway/**"
                        }
                    }
                ],
                "filters": [
                    {
                        "name": "RewritePath",
                        "args": {
                            "regexp": "/idc-gateway/(?<remaining>.*)",
                            "replacement": "/${remaining}"
                        }
                    }
                ],
                "uri": "lb://idc-gateway",
                "order": 0
            },
            "order": 0
        },
        {
            "route_id": "CompositeDiscoveryClient_idc-provider1",
            "route_definition": {
                "id": "CompositeDiscoveryClient_idc-provider1",
                "predicates": [
                    {
                        "name": "Path",
                        "args": {
                            "pattern": "/idc-provider1/**"
                        }
                    }
                ],
                "filters": [
                    {
                        "name": "RewritePath",
                        "args": {
                            "regexp": "/idc-provider1/(?<remaining>.*)",
                            "replacement": "/${remaining}"
                        }
                    }
                ],
                "uri": "lb://idc-provider1",
                "order": 0
            },
            "order": 0
        },
        {
            "route_id": "CompositeDiscoveryClient_idc-provider2",
            "route_definition": {
                "id": "CompositeDiscoveryClient_idc-provider2",
                "predicates": [
                    {
                        "name": "Path",
                        "args": {
                            "pattern": "/idc-provider2/**"
                        }
                    }
                ],
                "filters": [
                    {
                        "name": "RewritePath",
                        "args": {
                            "regexp": "/idc-provider2/(?<remaining>.*)",
                            "replacement": "/${remaining}"
                        }
                    }
                ],
                "uri": "lb://idc-provider2",
                "order": 0
            },
            "order": 0
        }
    ]

这个时候访问 [http://192.168.124.5:2000/idc-provider1/provider1/1][http_192.168.124.5_2000_idc-provider1_provider1_1] 根据结果可以推测能正确路由到 `provider1`， 测试结果一致。

1.  创建 `provider1` 路由，将路径设置为 `/p1/**`，测试是否生效。

`POST` 请求 [http://localhost:2000/gateway/add][http_localhost_2000_gateway_add]

{
       "id":"provider1",
       "predicates":[
          {
             "name":"Path",
             "args":{
                "_genkey_0":"/p1/**"
             }
          },
          {
             "name":"RemoteAddr",
             "args":{
                "_genkey_0":"192.168.124.5/16"
             }
          }
       ],
       "filters":[
          {
             "name":"StripPrefix",
             "args":{
                "_genkey_0":"1"
             }
          }
       ],
       "uri":"lb://idc-provider1",
       "order":0
    }

查看 `redis` 存储，或者请求 [http://localhost:2000/actuator/gateway/routes][http_localhost_2000_actuator_gateway_routes] , 都可以看到配置成功。

[https_www.cnblogs.com_idea360_p_12632801.html]: https://www.cnblogs.com/idea360/p/12632801.html
[http_localhost_2000_actuator_gateway_routes]: http://localhost:2000/actuator/gateway/routes
[http_192.168.124.5_2000_idc-provider1_provider1_1]: http://192.168.124.5:2000/idc-provider1/provider1/1
[http_localhost_2000_gateway_add]: http://localhost:2000/gateway/add