SpringCloudGateway路由定义存至Mysql数据库

SpringCloudGateway默认根据配置文件或代码在启动时路由定义存在内存中，如果要修改路由配置，需要改动配置文件或代码后重启网关，十分不灵活。

官方提供了RedisRouteDefinitionRepository可以将配置存放之Redis中，使用spring.cloud.gateway.redis-route-definition-repository.enabled开启。

可以实现RouteDefinitionRepository接口，将路由配置保存至Mysql中。

使用的SpringCloud版本为2021.0.5，文章编写于2022-12-12日。

ORM使用SpringDataR2DBC，相关教程请自行查找。

项目POM引入

<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-data-r2dbc</artifactId>
</dependency>
<dependency><groupId>com.github.jasync-sql</groupId><artifactId>jasync-r2dbc-mysql</artifactId>
</dependency>

路由定义实体

@Table(name = "`gateway_route_define`")
public class GatewayRouteDefineEntity implements Serializable {private static final long serialVersionUID = 1L;@Idprivate String id;private String uri;private String predicates;private String filters;private String metadata;@Column("`is_enable`")private Boolean enable;public String getId() {return id;}public void setId(String id) {this.id = id;}public String getUri() {return uri;}public void setUri(String uri) {this.uri = uri;}public String getPredicates() {return predicates;}public void setPredicates(String predicates) {this.predicates = predicates;}public String getFilters() {return filters;}public void setFilters(String filters) {this.filters = filters;}public String getMetadata() {return metadata;}public void setMetadata(String metadata) {this.metadata = metadata;}public Boolean isEnable() {return enable;}public void setEnable(Boolean enable) {this.enable = enable;}
}

DAO层

@Repository
public interface GatewayRouteDefineDao extends ReactiveCrudRepository<GatewayRouteDefineEntity, String> {/*** 查询所有启用的路由定义* @return 路由定义列表*/Flux<GatewayRouteDefineEntity> findAllByEnableTrue();
}

Service层

public interface GatewayRouteDefineService {/*** 查询所有实体** @return 路由实体列表*/Flux<GatewayRouteDefineEntity> findAll();/*** 保存** @param entity 路由实体* @return*/Mono<GatewayRouteDefineEntity> save(@RequestBody @Validated GatewayRouteDefineEntity entity);/*** 根据id删除实体** @param id 实体id* @return*/Mono<Void> deleteById(@PathVariable("id") String id);/*** 刷新路由定义** @return*/Mono<Void> refreshRouteDefinition();
}

@Service
public class GatewayRouteDefineServiceImpl implements GatewayRouteDefineService {private static final Logger log = LoggerFactory.getLogger(GatewayRouteDefineServiceImpl.class);private final GatewayRouteDefineDao gatewayRouteDefineDao;private final ApplicationEventPublisher publisher;public GatewayRouteDefineServiceImpl(GatewayRouteDefineDao gatewayRouteDefineDao,ApplicationEventPublisher publisher) {this.gatewayRouteDefineDao = gatewayRouteDefineDao;this.publisher = publisher;}@Overridepublic Flux<GatewayRouteDefineEntity> findAll() {return gatewayRouteDefineDao.findAllByEnableTrue();}@Overridepublic Mono<GatewayRouteDefineEntity> save(GatewayRouteDefineEntity entity) {return gatewayRouteDefineDao.save(entity);}@Overridepublic Mono<Void> deleteById(String id) {return gatewayRouteDefineDao.deleteById(id);}@Overridepublic Mono<Void> refreshRouteDefinition() {this.publisher.publishEvent(new RefreshRoutesEvent(this));return Mono.empty();}
}

实现RouteDefinitionRepository

@Configuration
public class RouteDefinitionConfiguration {@Beanpublic DbRouteDefinitionRepository dbRouteDefinitionRepository(GatewayRouteDefineService gatewayRouteDefineService) {return new DbRouteDefinitionRepository(gatewayRouteDefineService);}public static class DbRouteDefinitionRepository implements RouteDefinitionRepository {private final GatewayRouteDefineService gatewayRouteDefineService;public DbRouteDefinitionRepository(GatewayRouteDefineService gatewayRouteDefineService) {this.gatewayRouteDefineService = gatewayRouteDefineService;}@Overridepublic Flux<RouteDefinition> getRouteDefinitions() {return gatewayRouteDefineService.findAll().map(entity -> {try {return GatewayRouteDefineUtils.convert(entity);} catch (URISyntaxException | JsonProcessingException e) {throw new RuntimeException(e);}});}@Overridepublic Mono<Void> save(Mono<RouteDefinition> route) {return route.flatMap(r -> {try {GatewayRouteDefineEntity entity = GatewayRouteDefineUtils.convert(r);return gatewayRouteDefineService.save(entity).then();} catch (JsonProcessingException e) {return Mono.error(new RuntimeException(e));}});}@Overridepublic Mono<Void> delete(Mono<String> routeId) {return routeId.flatMap(gatewayRouteDefineService::deleteById);}}
}

工具类

public class GatewayRouteDefineUtils {private static final ObjectMapper OBJECT_MAPPER;static {OBJECT_MAPPER = new ObjectMapper();OBJECT_MAPPER.configure(DeserializationFeature.FAIL_ON_IGNORED_PROPERTIES, false);OBJECT_MAPPER.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);}public static RouteDefinition convert(GatewayRouteDefineEntity entity) throws URISyntaxException, JsonProcessingException {RouteDefinition definition = new RouteDefinition();definition.setId(entity.getId());definition.setUri(new URI(entity.getUri()));if (entity.getPredicates() != null) {List<PredicateDefinition> predicateDefinitions = OBJECT_MAPPER.readValue(entity.getPredicates(),new TypeReference<List<PredicateDefinition>>() { });definition.setPredicates(predicateDefinitions);}if (entity.getFilters() != null) {List<FilterDefinition> filterDefinitions = OBJECT_MAPPER.readValue(entity.getFilters(),new TypeReference<List<FilterDefinition>>() { });definition.setFilters(filterDefinitions);}return definition;}public static GatewayRouteDefineEntity convert(RouteDefinition definition) throws JsonProcessingException {GatewayRouteDefineEntity entity = new GatewayRouteDefineEntity();entity.setId(definition.getId());entity.setUri(definition.getUri().toString());entity.setPredicates(OBJECT_MAPPER.writeValueAsString(definition.getPredicates()));entity.setFilters(OBJECT_MAPPER.writeValueAsString(definition.getFilters()));return entity;}
}

测试Controller

@RestController
public class TestController {private static final Logger log = LoggerFactory.getLogger(TestController.class);private final GatewayRouteDefineService gatewayRouteDefineService;public TestController(GatewayRouteDefineService gatewayRouteDefineService) {this.gatewayRouteDefineService = gatewayRouteDefineService;}@RequestMapping("/refresh_route")public Mono<String> refreshRoute() {return gatewayRouteDefineService.refreshRouteDefinition().thenReturn("refresh success");}
}

数据库表

CREATE TABLE `gateway_route_define`  (`id` varchar(50) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NOT NULL COMMENT '主键',`uri` varchar(100) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '目的地址',`predicates` text CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL COMMENT '断言定义',`filters` text CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL COMMENT '过滤器定义',`metadata` text CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL COMMENT '扩展数据',`is_enable` tinyint(4) NULL DEFAULT NULL COMMENT '是否启用  0：否  1：是',`create_time` datetime(3) NULL DEFAULT NULL COMMENT '创建时间',PRIMARY KEY (`id`) USING BTREE
) ENGINE = InnoDB CHARACTER SET = utf8mb4 COLLATE = utf8mb4_general_ci COMMENT = '网关路由定义表' ROW_FORMAT = Dynamic;

插入一条测试数据

INSERT INTO `gateway_route_define` VALUES ('c707a482-77a3-11ed-a1eb-0242ac120002', 'https://www.baidu.com', '[{\"name\":\"Path\",\"args\":{\"pattern\":\"/baidu\"}}]', '[{\"name\":\"RewritePath\",\"args\":{\"regexp\":\"/baidu/?(?<segment>.*)\",\"replacement\":\"/$\\\\{segment}\"}},{\"name\":\"GuavaRateLimiter\",\"args\":{\"limit\":\"5\"}}]', '{}', 1, '2022-12-12 11:46:55.000');

其实数据库保存的字段就是RouteDefinition类中的字段，其中predicates、filters、metadata字段为JSON格式的数据。

路由定义序列化

Predicate序列化

其实就是对PredicateDefinition类进行序列化，包含name和args两个字段，其中args需要去org.springframework.cloud.gateway.handler.predicate路径下找具体的工厂类，里面有各参数的名称
例如

spring:cloud:gateway:routes:- id: path_routeuri: https://example.orgpredicates:- Path=/red/{segment},/blue/{segment}

这条路由规则中的

Path=/red/{segment},/blue/{segment}

其实现类是PathRoutePredicateFactory，那么args参数就是由PathRoutePredicateFactory.Config序列化而来。其余predicate和filter都是按此规则，这样应该就能理解插入的测试数据中predicates和filters字段的含义了。

测试

启动网关，会自动去数据库加载路由定义，当数据库路由修改后，可以调用GatewayRouteDefineService#refreshRouteDefinition来刷新路由，其实原理就是触发一个RefreshRoutesEvent事件，SpringCloudGateway会重新加载路由。