springboot 2.0 + springcloud alibaba 整合gateway（二）swagger分发

前言：

在实际开发当中前后端对接的时候，经常会用到swagger，但是如果使用了路由的话，如果不用路由网关去分发swagger的话，前后端对解决的时候会很麻烦，微服务的接口增多对于对接的成本就会变高，那么这一节就写一写gatewaty转发swagger

代码配置：

具体微服务

需要用到swagger的微服务上添加swagger的依赖，为了方便我这边直接就使用上一章用到的那个test接口的nacos客户端的项目

<?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">
    <parent>
        <groupId>com.gitee.simons.cloud</groupId>
        <artifactId>simons-cloud</artifactId>
        <version>0.0.1-SNAPSHOT</version>
    </parent>

    <modelVersion>4.0.0</modelVersion>
    <artifactId>simons-nacos</artifactId>
    <name>${project.artifactId} [web]</name>
    <packaging>jar</packaging>

    <!-- 版本，字段关键字 -->
    <properties>
        <start-class>com.gitee.simons.nacos.NacosApplication</start-class>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
        </dependency>

        <!--swagger相关 -->
        <dependency>
            <groupId>io.springfox</groupId>
            <artifactId>springfox-swagger2</artifactId>
            <version>2.9.2</version>
        </dependency>
        <dependency>
            <groupId>io.springfox</groupId>
            <artifactId>springfox-swagger-ui</artifactId>
            <version>2.9.2</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
    </dependencies>

<profiles>
        <profile>
            <id>spring-boot</id>
            <build>
                <plugins>
                    <plugin>
                        <groupId>org.springframework.boot</groupId>
                        <artifactId>spring-boot-maven-plugin</artifactId>
                        <version>${spring-boot.version}</version>
                        <configuration>
                            <mainClass>${start-class}</mainClass>
                        </configuration>
                        <executions>
                            <execution>
                                <goals>
                                    <goal>repackage</goal>
                                </goals>
                            </execution>
                        </executions>
                    </plugin>
                </plugins>
            </build>
        </profile>


    </profiles>


    <build>
        <finalName>${project.artifactId}</finalName>
        <plugins>
            <!--解決持續集成無法找到main類 -->
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <mainClass>${start-class}</mainClass>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

主要就是加上swagger，由于swagger的配置版本越高，功能越全面这边建议无脑最新relase，反正不在生产环境上出现的东西，怎么方便怎么来。

接下来就是要加上一些跨域和swagger的配置，直接复制我的代码即可

swagger的配置类，要注意的是，return的docket里面有个basePackagex需要根据实际的包路径填写的
复制的时候注意一下即可

package com.gitee.simons.nacos.swagger.config;

import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import springfox.documentation.builders.ApiInfoBuilder;
import springfox.documentation.builders.ParameterBuilder;
import springfox.documentation.builders.PathSelectors;
import springfox.documentation.builders.RequestHandlerSelectors;
import springfox.documentation.schema.ModelRef;
import springfox.documentation.service.ApiInfo;
import springfox.documentation.service.Contact;
import springfox.documentation.service.Parameter;
import springfox.documentation.spi.DocumentationType;
import springfox.documentation.spring.web.plugins.Docket;
import springfox.documentation.swagger.web.DocExpansion;
import springfox.documentation.swagger.web.OperationsSorter;
import springfox.documentation.swagger.web.UiConfiguration;
import springfox.documentation.swagger.web.UiConfigurationBuilder;
import springfox.documentation.swagger2.annotations.EnableSwagger2;

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

/**
 * SwaggerConfig api文档地址：/swagger-ui.html
 *
 * @author JSM
 */

@Configuration
public class SwaggerConfig {

    @Value("${spring.application.name}")
    private String applicationName;

    @Bean
    public Docket createRestApi() {
        // 构造token给测试的时候填写
        ParameterBuilder tokenPar = new ParameterBuilder();
        List<Parameter> pars = new ArrayList<Parameter>();
        tokenPar.name("token").description("用户令牌(不需用户鉴权的不需要传)").modelRef(new ModelRef("string")).parameterType("header")
                .required(false).build();
        pars.add(tokenPar.build());

        return new Docket(DocumentationType.SWAGGER_2)
                .apiInfo(defaultTitleInfo())
                .select()
                .apis(RequestHandlerSelectors.basePackage("com.gitee.simons"))
                .apis(RequestHandlerSelectors.withClassAnnotation(Api.class))
                .apis(RequestHandlerSelectors.withMethodAnnotation(ApiOperation.class))
                .paths(PathSelectors.any())
                .build().globalOperationParameters(pars);
    }

    /**
     * 默认标题信息
     *
     * @return
     */
    private ApiInfo defaultTitleInfo() {
        // 大标题
        return new ApiInfoBuilder().title("")
                // 详细描述
                .description("")
                .contact(new Contact("", "", ""))
                // 版本
                .version("4.0")
                .build();
    }

    @Bean
    UiConfiguration uiConfig() {
        return UiConfigurationBuilder.builder().docExpansion(DocExpansion.LIST).operationsSorter(OperationsSorter.ALPHA).build();
    }
}

swagger的资源过滤配置

package com.gitee.simons.nacos.swagger.config;

import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.CorsRegistry;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

/**
 * test
 *
 * @author: jsm
 * @date: 2018/11/16 10:40
 *
 */
@Configuration
public class WebMvcConfig implements WebMvcConfigurer {

    /**
     * 跨域支持
     * @param registry
     */
    @Override
    public void addCorsMappings(CorsRegistry registry) {
        registry.addMapping("/**")
                .allowedOrigins("*")
                .allowCredentials(true)
                .allowedMethods("*")
                .maxAge(3600)
                .allowedHeaders("X-Requested-With", "Content-Type","token");
    }

    /**
     * 添加静态资源--过滤swagger-api (开源的在线API文档)
     * @param registry
     */
    @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
        registry.addResourceHandler("/js/**").addResourceLocations("classpath:/js/");
        registry.addResourceHandler("swagger-ui.html")
                .addResourceLocations("classpath:/META-INF/resources/");
        registry.addResourceHandler("/webjars/**")
                .addResourceLocations("classpath:/META-INF/resources/webjars/");

    }

}

全局跨域配置

package com.gitee.simons.nacos.swagger.config;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

@Configuration
public class CrosAppConfig implements WebMvcConfigurer {
    
    @Autowired
    private CrosInterceptor crosInterceptor;

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        // 配置全局 的cros
        registry.addInterceptor(crosInterceptor).addPathPatterns("/**/**");
    }



}

跨域的详细信息设置

package com.gitee.simons.nacos.swagger.config;

import org.springframework.stereotype.Component;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@Component
public class CrosInterceptor extends HandlerInterceptorAdapter {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        //处理跨域名问题
        response.setHeader("Access-Control-Allow-Origin", "*");  
        response.setHeader("Access-Control-Allow-Methods", "*");  
        response.setHeader("Access-Control-Max-Age", "3600");    
        response.setHeader("Access-Control-Allow-Headers", "X-Requested-With,Content-Type,token");  
        response.setHeader("Access-Control-Allow-Credentials", "true");
        return true;
    }
}

那么只要复制了这些文件之后，在applicaiton文件上面加上@EnableSwagger2标签就可以的了

package com.gitee.simons.nacos;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.context.annotation.ComponentScan;
import springfox.documentation.swagger2.annotations.EnableSwagger2;

@SpringBootApplication
@EnableDiscoveryClient
@ComponentScan("com.gitee")
@EnableSwagger2
public class NacosApplication {

    public static void main(String[] args) {
        SpringApplication.run(NacosApplication.class, args);
    }
}

配置完这些信息之后，启动application在浏览器输入http://localhost:8112/swagger-ui.html
就可以直接请求到swagger的页面

image.png

gateway转发配置

这一步之后具体的微服务就可以实现请求了，但是我们的目标是需要可以做到gateway转发，那么应该还要再gateway项目下做一些操作

如果用过zuul做过路由转发的朋友，应该知道zuul是用的路由页面跳转的方式，这种方式得在serlvet的方式下才可以进行，但gateway是一个用netty框架为基础的服务，那么他就无法使用zuul的方式进行路由，但可以使用另外的方式，就是获取gateway路由参数中的服务，然后显示在select a spec上，通过请求swagger的v2/api-docs接口返回json数据，再放进swagger的页面中，大概这种思路

那么直接上配置

首先给gateway加上swagger的pom 依赖

        <!--swagger相关 -->
        <dependency>
            <groupId>io.springfox</groupId>
            <artifactId>springfox-swagger2</artifactId>
            <version>2.9.2</version>
        </dependency>
        <dependency>
            <groupId>io.springfox</groupId>
            <artifactId>springfox-swagger-ui</artifactId>
            <version>2.9.2</version>
        </dependency>

对swagger路由的配置

package com.sunmnet.mediaroom.gateway.config;

import lombok.AllArgsConstructor;
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;

/**
 * @author Sywd
 */
@Component
@Primary
@AllArgsConstructor
public class SwaggerProvider implements SwaggerResourcesProvider {
    public static final String API_URI = "/v2/api-docs";
    private final RouteLocator routeLocator;
    private final GatewayProperties gatewayProperties;


    @Override
    public List<SwaggerResource> get() {
        List<SwaggerResource> resources = new ArrayList<>();
        List<String> routes = new ArrayList<>();
        routeLocator.getRoutes().subscribe(route -> routes.add(route.getId()));
        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;
    }
}

因为swagger打开页面的时候，会默认请求一系列的请求，这些请求会返回页面信息的基本构成内容，
但由于gateway上用的是webflux，swagger是无法获取到这些信息的，那么我们只能自己伪造一个这些接口并返回成功的空信息，以此绕过报错，然后具体资源信息通过转发的请求各个微服务中获取

swagger资源报错信息绕过

package com.gitee.simons.gateway.config;

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

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

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

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

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

配置完之后，就可以启动application，请求通过swagger路由获取到具体的信息了

image.png