SpringCloudApiGateway之支持Cors跨域请求

问题背景

公司的项目需要前后端分离，vue+java，这时候就需要支持Cors跨域请求了。最近对zuul进行升级，假如说zuul是1.0的话，api gateway就是2.0的网关，支持ws等，基于NIO，各方面还是强大的。

解决方案

新建一个Configuration类即可。

import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.cloud.gateway.discovery.DiscoveryClientRouteDefinitionLocator;
import org.springframework.cloud.gateway.route.RouteDefinitionLocator;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpMethod;
import org.springframework.http.HttpStatus;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.web.cors.reactive.CorsUtils;
import org.springframework.web.server.ServerWebExchange;
import org.springframework.web.server.WebFilter;
import org.springframework.web.server.WebFilterChain;
import reactor.core.publisher.Mono;


/**
 * SpringApiGateway Cors
 */
@Configuration
public class RouteConfiguration {
    //这里为支持的请求头，如果有自定义的header字段请自己添加（不知道为什么不能使用*）
    private static final String ALLOWED_HEADERS = "x-requested-with, authorization, Content-Type, Authorization, credential, X-XSRF-TOKEN,token,username,client";
    private static final String ALLOWED_METHODS = "*";
    private static final String ALLOWED_ORIGIN = "*";
    private static final String ALLOWED_Expose = "x-requested-with, authorization, Content-Type, Authorization, credential, X-XSRF-TOKEN,token,username,client";
    private static final String MAX_AGE = "18000L";

    @Bean
    public WebFilter corsFilter() {
        return (ServerWebExchange ctx, WebFilterChain chain) -> {
            ServerHttpRequest request = ctx.getRequest();
            if (CorsUtils.isCorsRequest(request)) {
                ServerHttpResponse response = ctx.getResponse();
                HttpHeaders headers = response.getHeaders();
                headers.add("Access-Control-Allow-Origin", ALLOWED_ORIGIN);
                headers.add("Access-Control-Allow-Methods", ALLOWED_METHODS);
                headers.add("Access-Control-Max-Age", MAX_AGE);
                headers.add("Access-Control-Allow-Headers", ALLOWED_HEADERS);
                headers.add("Access-Control-Expose-Headers", ALLOWED_Expose);
                headers.add("Access-Control-Allow-Credentials", "true");
                if (request.getMethod() == HttpMethod.OPTIONS) {
                    response.setStatusCode(HttpStatus.OK);
                    return Mono.empty();
                }
            }
            return chain.filter(ctx);
        };
    }
    /**
    *
    *如果使用了注册中心（如：Eureka），进行控制则需要增加如下配置
    */
    @Bean
    public RouteDefinitionLocator discoveryClientRouteDefinitionLocator(DiscoveryClient discoveryClient) {
        return new DiscoveryClientRouteDefinitionLocator(discoveryClient);
    }
}

application.yml配置

官方文档提及到还有另外一种方式，就是通过yml来配置。
https://cloud.spring.io/spring-cloud-static/spring-cloud-gateway/2.1.0.RELEASE/multi/multi__cors_configuration.html

spring:
  cloud:
    gateway:
      globalcors:
        corsConfigurations:
          '[/**]':
            allowedOrigins: "https://blog.csdn.net/moshowgame"
            allowedMethods:
            - GET