Spring Cloud Gateway：使用RestController动态更新路由

相关类介绍

动态路由（自己控制，非注册中心控制）涉及两个很重要的Bean：

• RouteDefinitionWriter：用于添加、修改、删除路由规则。
• RouteDefinitionLocator：用于查询路由规则。

以及一个相关事件：

• RefreshRoutesEvent：用于更新路由规则，使上述的操作生效。

依赖及配置

先引入相关依赖：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.chilun</groupId>
    <artifactId>API_OPEN_SPACE_GATEWAY</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <java.version>17</java.version>
        <maven.compiler.source>17</maven.compiler.source>
        <maven.compiler.target>17</maven.compiler.target>
    </properties>

    <dependencyManagement>
        <dependencies>
                <dependency>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-dependencies</artifactId>
                    <version>2.7.9</version>
                    <type>pom</type>
                    <scope>import</scope>
                </dependency>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>2021.0.5</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <dependency>
                <groupId>com.alibaba.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>2021.0.5.0</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-gateway</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
            <version>2021.0.5.0</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-bootstrap</artifactId>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
        <dependency>
            <groupId>com.github.xiaoymin</groupId>
            <artifactId>knife4j-spring-boot-starter</artifactId>
            <version>3.0.3</version>
        </dependency>
    </dependencies>
</project>

以及配置文件application.yml：

server:
  port: 8002
logging:
  level:
    org.springframework.cloud.gateway: DEBUG
myGateway:
  RoutePrefix: api
spring:
  profiles:
    active: dev
  mvc:
    pathmatch:
      matching-strategy: ant_path_matcher
  cloud:
    gateway:
      enabled: true

服务中心相关配置：

spring.cloud.nacos.config.server-addr=127.0.0.1:8848
spring.application.name=gateway

核心代码

定义服务层接口：

import com.chilun.apiopenspace.gateway.entity.dto.DeleteRouteRequest;
import com.chilun.apiopenspace.gateway.entity.dto.InitRouteRequest;
import com.chilun.apiopenspace.gateway.entity.dto.SaveOrUpdateRouteRequest;
import com.chilun.apiopenspace.gateway.entity.pojo.RoutePOJO;
import reactor.core.publisher.Mono;

import java.util.List;

/**
 * @author 齿轮
 * @date 2024-02-08-22:39
 */
public interface RouteService {
    void init(InitRouteRequest request);
    void saveOrUpdate(SaveOrUpdateRouteRequest request);
    void delete(DeleteRouteRequest request);
    void refresh();
    Mono<List<RoutePOJO>> getAll();
}

实现类（适配器模式）：

package com.chilun.apiopenspace.gateway.service.impl;

import com.chilun.apiopenspace.gateway.entity.dto.DeleteRouteRequest;
import com.chilun.apiopenspace.gateway.entity.dto.InitRouteRequest;
import com.chilun.apiopenspace.gateway.entity.dto.SaveOrUpdateRouteRequest;
import com.chilun.apiopenspace.gateway.entity.pojo.RoutePOJO;
import com.chilun.apiopenspace.gateway.service.RouteService;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.cloud.gateway.event.RefreshRoutesEvent;
import org.springframework.cloud.gateway.filter.FilterDefinition;
import org.springframework.cloud.gateway.handler.predicate.PredicateDefinition;
import org.springframework.cloud.gateway.route.RouteDefinition;
import org.springframework.cloud.gateway.route.RouteDefinitionLocator;
import org.springframework.cloud.gateway.route.RouteDefinitionWriter;
import org.springframework.context.ApplicationEventPublisher;
import org.springframework.context.ApplicationEventPublisherAware;
import org.springframework.stereotype.Service;
import reactor.core.publisher.Mono;

import javax.annotation.PostConstruct;
import javax.annotation.Resource;
import java.net.URI;
import java.util.Collections;
import java.util.List;
import java.util.stream.Collectors;

/**
 * @author 齿轮
 * @date 2024-02-08-22:43
 */
@Service
public class RouteServiceAdepter implements RouteService, ApplicationEventPublisherAware {
    @Resource
    private RouteDefinitionWriter routeDefinitionWriter;
    @Resource
    private RouteDefinitionLocator locator;

    @Value("${myGateway.RoutePrefix}")
    private String routePrefix;

//    @PostConstruct
//    public void test(){
//        SaveOrUpdateRouteRequest saveOrUpdateRouteRequest = new SaveOrUpdateRouteRequest();
//        saveOrUpdateRouteRequest.setUri("https://www.baidu.com");
//        saveOrUpdateRouteRequest.setId("1");
//        saveOrUpdate(saveOrUpdateRouteRequest);
//    }

    @Override
    public void init(InitRouteRequest request) {
        request.getList().forEach(this::saveOrUpdate);
        this.publisher.publishEvent(new RefreshRoutesEvent(this));
    }

    @Override
    public void saveOrUpdate(SaveOrUpdateRouteRequest request) {
        RouteDefinition routeDefinition = new RouteDefinition();
        routeDefinition.setId(request.getId());
        routeDefinition.setUri(URI.create(request.getUri()));
        String Path = "/" + routePrefix + "/" + request.getId();
        routeDefinition.setPredicates(Collections.singletonList(new PredicateDefinition("Path=" + Path)));
        routeDefinition.setFilters(Collections.singletonList(new FilterDefinition("SetPath=/")));
        routeDefinitionWriter.save(Mono.just(routeDefinition)).subscribe();
    }

    @Override
    public void delete(DeleteRouteRequest request) {
        routeDefinitionWriter.delete(Mono.just(request.getId())).subscribe();
        this.publisher.publishEvent(new RefreshRoutesEvent(this));
    }

    @Override
    public void refresh() {
        this.publisher.publishEvent(new RefreshRoutesEvent(this));
    }

    @Override
    public Mono<List<RoutePOJO>> getAll() {
        return locator.getRouteDefinitions()
                .map(routeDefinition -> {
                    RoutePOJO routePOJO = new RoutePOJO();
                    routePOJO.setId(routeDefinition.getId());
                    routePOJO.setURI(routeDefinition.getUri().toString());
                    routePOJO.setPredicates(routeDefinition.getPredicates().stream()
                            .map(predicate -> predicate.getArgs().values().toString())
                            .collect(Collectors.toList()));
                    routePOJO.setFilters(routeDefinition.getFilters().stream()
                            .map(FilterDefinition::getName)
                            .collect(Collectors.toList()));
                    return routePOJO;
                })
                .collectList();
    }

    private ApplicationEventPublisher publisher;

    @Override
    public void setApplicationEventPublisher(ApplicationEventPublisher applicationEventPublisher) {
        this.publisher = applicationEventPublisher;
    }
}

Controller层代码：

package com.chilun.apiopenspace.gateway.controller;

import com.chilun.apiopenspace.gateway.entity.dto.DeleteRouteRequest;
import com.chilun.apiopenspace.gateway.entity.dto.InitRouteRequest;
import com.chilun.apiopenspace.gateway.entity.dto.SaveOrUpdateRouteRequest;
import com.chilun.apiopenspace.gateway.entity.pojo.RoutePOJO;
import com.chilun.apiopenspace.gateway.service.RouteService;
import org.springframework.web.bind.annotation.*;
import reactor.core.publisher.Mono;

import javax.annotation.Resource;
import java.util.List;

/**
 * @author 齿轮
 * @date 2024-02-13-22:13
 */
@RestController
@RequestMapping("/manage")
public class RouteController {
    @Resource
    RouteService service;

    @PostMapping("/update")
    public void add(@RequestBody SaveOrUpdateRouteRequest request) {
        service.saveOrUpdate(request);
    }

    @PostMapping("/init")
    public void init(@RequestBody InitRouteRequest request) {
        service.init(request);
    }

    @PostMapping("/delete")
    public void delete(@RequestBody DeleteRouteRequest request) {
        service.delete(request);
    }

    @GetMapping("/getAll")
    public Mono<List<RoutePOJO>> getAll() {
        return service.getAll();
    }

    @GetMapping("/refresh")
    public void refresh(){
        service.refresh();
    }
}

代码请自行查看，看不懂就问大语言模型。

代码逻辑较简单，仅基本增删改查功能，其他延伸方面如安全等请自行探索。

其他代码

实体类：

package com.chilun.apiopenspace.gateway.entity.dto;

import lombok.Data;

/**
 * @author 齿轮
 * @date 2024-02-13-20:01
 */
@Data
public class DeleteRouteRequest {
    String id;
}

package com.chilun.apiopenspace.gateway.entity.dto;

import lombok.Data;

import java.util.List;

/**
 * @author 齿轮
 * @date 2024-02-13-20:00
 */
@Data
public class InitRouteRequest {
    List<SaveOrUpdateRouteRequest> list;
}

package com.chilun.apiopenspace.gateway.entity.dto;

import lombok.Data;

/**
 * @author 齿轮
 * @date 2024-02-13-19:55
 */
@Data
public class SaveOrUpdateRouteRequest {
    String id;
    String uri;
}

package com.chilun.apiopenspace.gateway.entity.pojo;

import lombok.Data;

import java.util.List;

/**
 *
 * Route实体类，用于远程调用接受参数
 * @author 齿轮
 * @date 2024-02-13-19:53
 */
@Data
public class RoutePOJO {
    String id;
    String URI;
    List<String> Predicates;
    List<String> Filters;
}

swagger文档配置类：

package com.chilun.apiopenspace.gateway.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Profile;
import springfox.documentation.builders.ApiInfoBuilder;
import springfox.documentation.builders.PathSelectors;
import springfox.documentation.builders.RequestHandlerSelectors;
import springfox.documentation.service.Contact;
import springfox.documentation.spi.DocumentationType;
import springfox.documentation.spring.web.plugins.Docket;
import springfox.documentation.swagger2.annotations.EnableSwagger2;

/**
 * @author 齿轮
 * @date 2024-02-14-1:32
 */
@Configuration
@EnableSwagger2
@Profile({"dev"})
public class Knife4jConfig {
    @Bean
    public Docket defaultApi2() {
        return new Docket(DocumentationType.SWAGGER_2)
                .apiInfo(new ApiInfoBuilder()
                        .title("API开放平台接口文件")
                        .description("API开放平台")
                        .contact(new Contact("chilun", "http://home.shoumingchilun.cn", "2265501251@qq.com"))
                        .version("1.0")
                        .build())
                .select()
                // 指定 Controller 扫描包路径
                .apis(RequestHandlerSelectors.basePackage("com.chilun.apiopenspace.gateway.controller"))
                .paths(PathSelectors.any())
                .build();
    }
}