<!-- Spring Cloud Gateway 核心 -->
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-gateway</artifactId>
</dependency>
<!-- Nacos 配置中心（用于存儲(chǔ)路由規(guī)則） -->
<dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
</dependency>
<!-- Nacos 服務(wù)發(fā)現(xiàn)（可選，用于服務(wù)名路由） -->
<dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
</dependency>

spring:
  application:
    name: gateway-service  # 服務(wù)名，對(duì)應(yīng) Nacos 配置的 Data ID
  cloud:
    nacos:
      config:
        server-addr: localhost:8848  # Nacos 服務(wù)器地址
        file-extension: yaml  # 配置文件格式

spring:
  cloud:
    gateway:
      routes:
        - id: user-service-route
          uri: lb://user-service  # 負(fù)載均衡到 user-service 服務(wù)
          predicates:
            - Path=/api/user/**
          filters:
            - StripPrefix=1  # 去除路徑前綴 /api
        - id: order-service-route
          uri: lb://order-service
          predicates:
            - Path=/api/order/**
          filters:
            - StripPrefix=1

import com.alibaba.cloud.nacos.NacosConfigManager;
import com.alibaba.cloud.nacos.NacosPropertySourceRepository;
import com.alibaba.nacos.api.config.listener.Listener;
import com.alibaba.nacos.api.exception.NacosException;
import org.springframework.beans.factory.annotation.Autowired;
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.context.annotation.Configuration;
import org.springframework.util.CollectionUtils;
import reactor.core.publisher.Mono;
import javax.annotation.PostConstruct;
import java.util.List;
import java.util.concurrent.Executor;
@Configuration
public class NacosDynamicRouteConfig implements ApplicationEventPublisherAware {
    @Autowired
    private NacosConfigManager nacosConfigManager;
    @Autowired
    private RouteDefinitionWriter routeDefinitionWriter;
    private ApplicationEventPublisher publisher;
    // 路由配置的 Data ID（與 Nacos 中一致）
    private static final String DATA_ID = "gateway-service.yaml";
    // 路由配置的 Group
    private static final String GROUP = "DEFAULT_GROUP";
    @PostConstruct
    public void init() throws NacosException {
        // 1. 初始化加載路由配置
        String configInfo = nacosConfigManager.getConfigService().getConfig(DATA_ID, GROUP, 5000);
        loadRouteConfig(configInfo);
        // 2. 監(jiān)聽 Nacos 配置變更
        nacosConfigManager.getConfigService().addListener(DATA_ID, GROUP, new Listener() {
            @Override
            public void receiveConfigInfo(String configInfo) {
                // 配置變更時(shí)重新加載路由
                loadRouteConfig(configInfo);
            }
            @Override
            public Executor getExecutor() {
                return null;
            }
        });
    }
    // 解析配置并更新路由
    private void loadRouteConfig(String configInfo) {
        try {
            // 從配置中解析出 RouteDefinition 列表（需自定義解析邏輯，或借助 Spring 配置綁定）
            List<RouteDefinition> routeDefinitions = parseRouteDefinitions(configInfo);
            // 先清空舊路由
            routeDefinitionWriter.delete(Mono.just("*")).block();
            // 再添加新路由
            if (!CollectionUtils.isEmpty(routeDefinitions)) {
                routeDefinitions.forEach(route -> {
                    routeDefinitionWriter.save(Mono.just(route)).block();
                });
            }
            // 發(fā)布刷新事件，通知網(wǎng)關(guān)更新路由
            this.publisher.publishEvent(new RefreshRoutesEvent(this));
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    // 解析配置字符串為 RouteDefinition 列表（需根據(jù)實(shí)際配置格式實(shí)現(xiàn)）
    private List<RouteDefinition> parseRouteDefinitions(String configInfo) {
        // 示例：使用 Spring 的 YamlPropertiesFactoryBean 解析配置
        // 實(shí)際需根據(jù) configInfo 中的內(nèi)容提取 spring.cloud.gateway.routes 節(jié)點(diǎn)
        // 此處省略具體解析邏輯，可參考 Spring Cloud Gateway 的配置綁定方式
        return null;
    }
    @Override
    public void setApplicationEventPublisher(ApplicationEventPublisher applicationEventPublisher) {
        this.publisher = applicationEventPublisher;
    }
}

CREATE TABLE `gateway_route` (
  `id` varchar(64) NOT NULL COMMENT '路由ID',
  `uri` varchar(255) NOT NULL COMMENT '目標(biāo)地址（如 lb://user-service）',
  `predicates` text COMMENT '斷言規(guī)則（JSON格式，如 [{"name":"Path","args":{"pattern":"/api/user/**"}}]）',
  `filters` text COMMENT '過濾器規(guī)則（JSON格式）',
  `order` int(11) DEFAULT 0 COMMENT '路由優(yōu)先級(jí)（值越小越優(yōu)先）',
  `status` tinyint(1) DEFAULT 1 COMMENT '狀態(tài)（1-啟用，0-禁用）',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

@Configuration
public class DbRouteDefinitionLocator implements RouteDefinitionLocator {
    @Autowired
    private JdbcTemplate jdbcTemplate;
    @Override
    public Flux<RouteDefinition> getRouteDefinitions() {
        // 從數(shù)據(jù)庫(kù)查詢啟用的路由
        List<RouteDefinition> routes = jdbcTemplate.query(
            "SELECT id, uri, predicates, filters, `order` FROM gateway_route WHERE status = 1",
            (rs, rowNum) -> {
                RouteDefinition route = new RouteDefinition();
                route.setId(rs.getString("id"));
                route.setUri(URI.create(rs.getString("uri")));
                route.setOrder(rs.getInt("order"));
                // 解析斷言（JSON -> List<PredicateDefinition>）
                String predicatesJson = rs.getString("predicates");
                List<PredicateDefinition> predicates = JSON.parseArray(predicatesJson, PredicateDefinition.class);
                route.setPredicates(predicates);
                // 解析過濾器（JSON -> List<FilterDefinition>）
                String filtersJson = rs.getString("filters");
                List<FilterDefinition> filters = JSON.parseArray(filtersJson, FilterDefinition.class);
                route.setFilters(filters);
                return route;
            }
        );
        return Flux.fromIterable(routes);
    }
}

@Component
public class DbRouteRefreshTask {
    @Autowired
    private DbRouteDefinitionLocator dbRouteLocator;
    @Autowired
    private RouteDefinitionWriter routeWriter;
    @Autowired
    private ApplicationEventPublisher publisher;
    // 每30秒刷新一次
    @Scheduled(fixedRate = 30000)
    public void refreshRoutes() {
        try {
            // 清空舊路由
            routeWriter.delete(Mono.just("*")).block();
            // 加載新路由
            dbRouteLocator.getRouteDefinitions().collectList().block()
                .forEach(route -> routeWriter.save(Mono.just(route)).block());
            // 發(fā)布刷新事件
            publisher.publishEvent(new RefreshRoutesEvent(this));
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}