Spring Cloud Gateway + Nacos 实现动态路由-编程知识

1、maven 依赖

主要依赖

		<!-- 网关 --><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-gateway</artifactId></dependency>

案件差不多完整主要依赖

		<!--Spring boot 依赖(微服务基础)--><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter</artifactId><!--使用exclusions标签来标明要排除的包--><!--排除logback--><exclusions><exclusion><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-logging</artifactId></exclusion></exclusions></dependency><!--Web 服务相关--><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><!-- 生成配置元数据，比如你平常在yml文件里面配置 --><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-configuration-processor</artifactId><optional>true</optional></dependency><!--单元测试依赖,子工程中需要单元测试时,不需要再次引入此依赖了--><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope><exclusions><exclusion><groupId>org.junit.vintage</groupId><artifactId>junit-vintage-engine</artifactId></exclusion></exclusions></dependency><!--bootstrap 相关--><!--SpringBoot2.4.x之后默认不加载bootstrap.yml文件，需要在pom里加上依赖--><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-bootstrap</artifactId><version>4.0.0</version></dependency><!--服务的注册和发现--><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></dependency><!--lombok 依赖,子工程中假如需要lombok,不需要再引入--><!-- https://mvnrepository.com/artifact/org.projectlombok/lombok --><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><version>1.18.30</version><scope>provided</scope></dependency><!-- 网关 --><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-gateway</artifactId></dependency>

2、bootstrap.yml配置

server:port: 9999tomcat:max-http-form-post-size: -1max-threads: 500min-spare-threads: 50servlet:context-path: /
spring:main:web-application-type: reactive#当遇到同样名字的时候，是否允许覆盖注册allow-bean-definition-overriding: true profiles:active: ${SYS_ENV:} # local:本地，dev：测试，uat:uatapplication:name: gateway-servicecloud:nacos:# 配置中心#config:username: ${NACOS_USER:nacos}password: ${NACOS_PASSWORD:nacos}server-addr: ${NACOS_IP:nacos.com}:${NACOS_POST:8848}namespace: ${NACOS_NAMESPACE:}file-extension: ymlrefresh-enabled: trueoverride-none: true  #本地配置优先shared-configs:- application.${spring.cloud.nacos.config.file-extension} # 配置文件名-Data Id# 路由网关配置gateway:# 启用了自动根据服务名建立路由discovery:locator:enabled: truelower-case-service-id: true# 动态路由配置
config:# 动态gateway-route:# nacos 配置dataIddataId: gateway-router# nacos服务地址server-addr: ${spring.cloud.nacos.config.server-addr}# 命名空间namespace: ${spring.cloud.nacos.config.namespace}

3、nacos 中心网关路由配置

nacos - 网关路由配置截图

[{"id": "auth-service","uri": "lb://auth-service","predicates": [{"args": {"pattern": "/auth-service/**"},"name": "Path"}],"filters": [{"args": {"parts": 1},"name": "StripPrefix"}],"order": 1},{"id": "user-service","uri": "lb://user-service","predicates": [{"args": {"pattern": "/user-service/**"},"name": "Path"}],"filters": [{"args": {"parts": 1},"name": "StripPrefix"}],"order": 2}
]

4、配置文件 GatewayRouteConfig

import cn.hutool.core.lang.Assert;
import cn.hutool.core.util.StrUtil;
import com.alibaba.fastjson.JSONObject;
import com.alibaba.nacos.api.NacosFactory;
import com.alibaba.nacos.api.config.ConfigService;
import com.alibaba.nacos.api.config.listener.Listener;
import com.alibaba.nacos.api.exception.NacosException;
import jakarta.annotation.PostConstruct;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.cloud.context.config.annotation.RefreshScope;
import org.springframework.cloud.gateway.event.RefreshRoutesEvent;
import org.springframework.cloud.gateway.route.RouteDefinition;
import org.springframework.cloud.gateway.route.RouteDefinitionWriter;
import org.springframework.context.ApplicationEventPublisher;
import org.springframework.context.ApplicationEventPublisherAware;
import org.springframework.stereotype.Component;
import reactor.core.publisher.Mono;import java.util.ArrayList;
import java.util.List;
import java.util.Properties;
import java.util.concurrent.Executor;/*** 类描述：通过Nacos的配置动态更新网管路由* <pre>*     ApplicationEventPublisherAware 是由 Spring 提供的用于为 Service 注入 ApplicationEventPublisher 事件发布器的接口，使用这个接口，*     我们自己的 Service 就拥有了发布事件的能力。用户注册后，不再是显示地调用其他的业务 Service，而是发布一个用户注册事件。* </pre>**/
@Slf4j
@RefreshScope
@Component
public class GatewayRouteConfig implements ApplicationEventPublisherAware {/** 常量 */private static final String PROPERTIES_SERVER_ADDR = "serverAddr";private static final String PROPERTIES_NAMESPACE = "namespace";private static final String PROPERTIES_GROUP = "group";/** nacos 配置dataId */@Value("${config.gateway-route.dataId:gateway-router}")private String dataId = "gateway-routes";/** nacos 配置group */@Value("${config.gateway-route.group:DEFAULT_GROUP}")private String group = "DEFAULT_GROUP";/** nacos 配置地址 */@Value("${config.gateway-route.server-addr}")private String serverAddr;/** nacos 命名空间 */@Value("${config.gateway-route.namespace}")private String namespace;/** 已加载的路由id集合 */private static final List<String> ROUTE_LIST = new ArrayList<>();private final RouteDefinitionWriter routeDefinitionWriter;/** 事件发布器 */private ApplicationEventPublisher applicationEventPublisher;/*** 方法描述： 构造函数** @param routeDefinitionWriter 路由定义写对象*/public GatewayRouteConfig(RouteDefinitionWriter routeDefinitionWriter) {this.routeDefinitionWriter = routeDefinitionWriter;}@Overridepublic void setApplicationEventPublisher(ApplicationEventPublisher applicationEventPublisher) {this.applicationEventPublisher = applicationEventPublisher;}/*** 方法描述： 从Nacos的配置中加载动态路由**/@PostConstructpublic void loadRouteFromNacosAndListener() {try {ConfigService configService = NacosFactory.createConfigService(getProperties());// 程序启动时调用Nacos的配置进行路由加载String initConfigInfo = configService.getConfig(dataId, group, 5000);addRouteAndPublish(initConfigInfo);// 添加监听路由变化addListener(configService);} catch (NacosException e) {log.error("加载路由配置错误，详情：", e);}}/*** 方法描述： 添加监听** @param cs 配置服务对象*/private void addListener(ConfigService cs) throws NacosException {// 添加监听cs.addListener(dataId, group, new Listener() {@Overridepublic void receiveConfigInfo(String configInfo) {// 将监听到的路由加载到路由定义器中addRouteAndPublish(configInfo);}@Overridepublic Executor getExecutor() {return null;}});}/*** 方法描述： Nacos配置属性** @return {@link Properties}*/private Properties getProperties() {Assert.notBlank(serverAddr, "Nacos的服务地址为空了！");Properties properties = new Properties();properties.put(PROPERTIES_SERVER_ADDR, serverAddr);if (StrUtil.isNotBlank(namespace)) {properties.put(PROPERTIES_NAMESPACE, namespace);}if (StrUtil.isNotBlank(group)) {properties.put(PROPERTIES_GROUP, group);}return properties;}/*** 添加并发布配置的路由** @param configInfo 路由配置字符串；格式：JSON数组*/private void addRouteAndPublish(String configInfo) {// 加载前需要清空有存在的路由clearRoute();// 解析从Nacos配置中读取的路由配置信息List<RouteDefinition> gatewayRouteDefinitions = JSONObject.parseArray(configInfo, RouteDefinition.class);for (RouteDefinition routeDefinition : gatewayRouteDefinitions) {// 将路由写到定义器中routeDefinitionWriter.save(Mono.just(routeDefinition)).subscribe();// 将路由id加入内存集合中ROUTE_LIST.add(routeDefinition.getId());}// 刷新路由定义器this.applicationEventPublisher.publishEvent(new RefreshRoutesEvent(this.routeDefinitionWriter));}/*** 方法描述： 清空已存在的路由*/private void clearRoute() {ROUTE_LIST.forEach(id -> this.routeDefinitionWriter.delete(Mono.just(id)).subscribe());ROUTE_LIST.clear();}
}