Spring Cloud Gateway网关模块聚合各微服务的Swagger接口文档

效果如下图：
相关pom依赖

        <!-- 网关路由代理 (仅网关)-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-gateway</artifactId>
            <version>2.2.5.RELEASE</version>
        </dependency>
        <!--swagger2 (网关和服务端)-->
        <dependency>
            <groupId>com.spring4all</groupId>
            <artifactId>swagger-spring-boot-starter</artifactId>
            <version>1.7.0.RELEASE</version>
        </dependency>

Gateway配置
因为Swagger暂不支持webflux项目，所以Gateway里不能配置SwaggerConfig

import org.springframework.cloud.gateway.config.GatewayProperties;
import org.springframework.cloud.gateway.route.RouteLocator;
import org.springframework.cloud.gateway.support.NameUtils;
import org.springframework.context.annotation.Primary;
import org.springframework.stereotype.Component;
import springfox.documentation.swagger.web.SwaggerResource;
import springfox.documentation.swagger.web.SwaggerResourcesProvider;

import java.util.ArrayList;
import java.util.List;

/**
 * 功能描述: 采用路由id做资源名称,predicates.Path做映射的方式.
 * 如果需要自定义资源名称,可以单独配置一个集合(route.id,name),创建swaggerResource时,
 * 通过route.id获取name.
 * <p>例如:     swagger:
 *               route_names:
 *                 - name: 订单
 *                   id: order_route
 *                 - name: 订单1
 *                   id: order_route1
 *              spring: cloud: gateway: routes:
 *                                         - id: order_route
 *                                         - id: order_route1
 *  </p>
 * 重新Gateway的方法还没研究出来 - -||
 *
 * @Author:
 * @Date: 2021-04-25 15:38
 * @Version 1.0
 **/
@Component
@Primary
public class Swagger2 implements SwaggerResourcesProvider {

    protected static final String API_URI = "/v2/api-docs";//固定后缀
    private final RouteLocator routeLocator;
    private final GatewayProperties gatewayProperties;
    //资源集合
    private static List<SwaggerResource> resources;
	//自定义资源名称需要在这里初始化
    public Swagger2(RouteLocator routeLocator, GatewayProperties gatewayProperties) {
        this.routeLocator = routeLocator;
        this.gatewayProperties = gatewayProperties;
    }

    @Override
    public List<SwaggerResource> get() {
    //做了一个简单缓存,没仔细设计,其实可有可无用处不大
        if (resources == null) {
            resources = new ArrayList<>();

            List<String> routes = new ArrayList<>();
            routeLocator.getRoutes().subscribe(route -> routes.add(route.getId()));
            //结合配置的route-路径(Path)，和route过滤，只获取有效的route节点
            gatewayProperties.getRoutes().stream()
                    .filter(routeDefinition -> routes.contains(routeDefinition.getId()))
                    .forEach(routeDefinition -> routeDefinition.getPredicates().stream()
                            .filter(predicateDefinition -> ("Path").equalsIgnoreCase(predicateDefinition.getName()))
                            .forEach(predicateDefinition -> resources.add(swaggerResource(routeDefinition.getId(),
                                    predicateDefinition.getArgs().get(NameUtils.GENERATED_NAME_PREFIX + "0")
                                            .replace("/**", API_URI)))));
        }
        return resources;
    }

    private SwaggerResource swaggerResource(String name, String location) {
        SwaggerResource swaggerResource = new SwaggerResource();
        swaggerResource.setName(name);
        swaggerResource.setLocation(location);
        swaggerResource.setSwaggerVersion("2.0");
        return swaggerResource;
    }

}

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import reactor.core.publisher.Mono;
import springfox.documentation.swagger.web.*;

import java.util.Optional;

@RestController
@RequestMapping("/swagger-resources")
public class SwaggerHandler {
    @Autowired(required = false)
    private SecurityConfiguration securityConfiguration;
    @Autowired(required = false)
    private UiConfiguration uiConfiguration;
    private final SwaggerResourcesProvider swaggerResources;

    @Autowired
    public SwaggerHandler(SwaggerResourcesProvider swaggerResources) {
        this.swaggerResources = swaggerResources;
    }


    @GetMapping("/configuration/security")
    public Mono<ResponseEntity<SecurityConfiguration>> securityConfiguration() {
        return Mono.just(new ResponseEntity<>(
                Optional.ofNullable(securityConfiguration).orElse(SecurityConfigurationBuilder.builder().build()), HttpStatus.OK));
    }

    @GetMapping("/configuration/ui")
    public Mono<ResponseEntity<UiConfiguration>> uiConfiguration() {
        return Mono.just(new ResponseEntity<>(
                Optional.ofNullable(uiConfiguration).orElse(UiConfigurationBuilder.builder().build()), HttpStatus.OK));
    }

    @GetMapping("")
    public Mono<ResponseEntity> swaggerResources() {
    	//入口
        return Mono.just((new ResponseEntity<>(swaggerResources.get(), HttpStatus.OK)));
    }
}

swagger地址过滤器

import org.apache.commons.lang.StringUtils;
import org.springframework.cloud.gateway.filter.GatewayFilter;
import org.springframework.cloud.gateway.filter.factory.AbstractGatewayFilterFactory;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.stereotype.Component;
import org.springframework.web.server.ServerWebExchange;

@Component
public class SwaggerHeaderFilter extends AbstractGatewayFilterFactory {
    private static final String HEADER_NAME = "X-Forwarded-Prefix";

    @Override
    public GatewayFilter apply(Object config) {
        return (exchange, chain) -> {
            ServerHttpRequest request = exchange.getRequest();
            String path = request.getURI().getPath();
            if (!StringUtils.endsWithIgnoreCase(path, Swagger2.API_URI)) {
                return chain.filter(exchange);
            }

            String basePath = path.substring(0, path.lastIndexOf(Swagger2.API_URI));

            ServerHttpRequest newRequest = request.mutate().header(HEADER_NAME, basePath).build();
            ServerWebExchange newExchange = exchange.mutate().request(newRequest).build();
            return chain.filter(newExchange);
        };
    }

}

服务端

import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import springfox.documentation.builders.ApiInfoBuilder;
import springfox.documentation.builders.PathSelectors;
import springfox.documentation.builders.RequestHandlerSelectors;
import springfox.documentation.service.ApiInfo;
import springfox.documentation.service.ApiKey;
import springfox.documentation.service.AuthorizationScope;
import springfox.documentation.service.SecurityReference;
import springfox.documentation.spi.DocumentationType;
import springfox.documentation.spi.service.contexts.SecurityContext;
import springfox.documentation.spring.web.plugins.Docket;
import springfox.documentation.swagger2.annotations.EnableSwagger2;

import java.util.ArrayList;
import java.util.List;

/**
 * 功能描述: Swagger2 接口文档
 *
 * @Author: 
 * @Date: 2021-04-23 15:59
 * @Version 1.0
 **/
@Configuration
@EnableSwagger2
public class Swagger2 {
    //是否开启swagger，正式环境一般是需要关闭的，可根据springboot的多环境配置进行设置
    @Value(value = "${swagger.enabled}")
    private Boolean swaggerEnabled;
    //显示文档版本
    @Value(value = "${swagger.version}")
    private String version;
    //标题
    @Value(value = "${swagger.title}")
    private String title;
    //描述信息
    @Value(value = "${swagger.description}")
    private String description;
    //扫描接口位置 也可以配置到nacos中
    private static final String base_package = "com.demo.controller";

    @Bean
    public Docket createRestApi() {

        return new Docket(DocumentationType.SWAGGER_2)// 指定api类型为swagger2
                .apiInfo(apiInfo())// 用于定义api文档汇总信息
                // 是否开启
                .enable(swaggerEnabled).select()
                // 扫描的路径包
                .apis(RequestHandlerSelectors.basePackage(base_package))
                // 指定路径处理PathSelectors.any()代表所有的路径
                .paths(PathSelectors.any()).build()
                .pathMapping("/")
                .securitySchemes(securitySchemes())
                .securityContexts(securityContexts());
    }

    //securitySchemes的ApiKey中增加一个名为“Authorization”，type为“header”的参数
    private List<ApiKey> securitySchemes() {
        List<ApiKey> apiKeyList = new ArrayList();
        apiKeyList.add(new ApiKey("Authorization", "Authorization", "header"));
        return apiKeyList;
    }

    private List<SecurityReference> defaultAuth() {
        AuthorizationScope authorizationScope = new AuthorizationScope("global", "accessEverything");
        AuthorizationScope[] authorizationScopes = new AuthorizationScope[1];
        authorizationScopes[0] = authorizationScope;
        List<SecurityReference> securityReferences = new ArrayList<>();
        securityReferences.add(new SecurityReference("Authorization", authorizationScopes));
        return securityReferences;
    }

    private List<SecurityContext> securityContexts() {
        List<SecurityContext> securityContexts = new ArrayList<>();
        securityContexts.add(
                SecurityContext.builder()
                        .securityReferences(defaultAuth())
                        .forPaths(PathSelectors.regex("^(?!auth).*$"))
                        .build());
        return securityContexts;
    }

    private ApiInfo apiInfo() {
        return new ApiInfoBuilder()
                .title(title)// 文档页标题
                .contact(new Contact("s","s.com","s@163.com"))// 详细信息
                .version(version)// 文档版本号
                .termsOfServiceUrl("www.baidu.com")// 网站地址
                .description(description)
                .build();
    }
}

```java