spring-cloud-gateway 的跨域处理

一、起因

   gateway作为网关，外界请求会经过这个网关，访问我们具体的服务，这时候会出现跨域问题。

二、解决策略

   1、基于配置的解决方案

      注意：allowedMethods: "*"    表示所有方法

spring:
  cloud:
	gateway:
	  globalcors:
		corsConfigurations:
		  '[/**]':
			allowedOrigins: "*"
			exposedHeaders:
			  - content-type
			allowedHeaders:
			  - content-type
			allowCredentials: true
			allowedMethods:
			  - GET
			  - OPTIONS
			  - PUT
			  - DELETE
			  - POST

 2、基于代码的实现

package com.allen.gateway.config;

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.CorsConfiguration;
import org.springframework.web.cors.reactive.CorsUtils;
import org.springframework.web.cors.reactive.CorsWebFilter;
import org.springframework.web.cors.reactive.UrlBasedCorsConfigurationSource;
import org.springframework.web.server.ServerWebExchange;
import org.springframework.web.server.WebFilter;
import org.springframework.web.server.WebFilterChain;
import org.springframework.web.util.pattern.PathPatternParser;
import reactor.core.publisher.Mono;

/**
 * 代码配置方式配置跨域
 * @author xuguocai 2020/6/30 17:13
 */
@Configuration
public class CorsConfig {

    /**
     * 跨域处理方式一
     * @return
     */
    @Bean
    public CorsWebFilter corsFilter() {
        CorsConfiguration config = new CorsConfiguration();
        config.addAllowedMethod("*");
        config.addAllowedOrigin("*");
        config.addAllowedHeader("*");

        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource(new PathPatternParser());
        source.registerCorsConfiguration("/**", config);

        return new CorsWebFilter(source);
    }

    /**
     * 跨域处理方式二
     * @return
     */
    @Bean
    public WebFilter corsFilter2() {
        return (ServerWebExchange ctx, WebFilterChain chain) -> {
            ServerHttpRequest request = ctx.getRequest();
            if (CorsUtils.isCorsRequest(request)) {
                HttpHeaders requestHeaders = request.getHeaders();
                ServerHttpResponse response = ctx.getResponse();
                HttpMethod requestMethod = requestHeaders.getAccessControlRequestMethod();
                HttpHeaders headers = response.getHeaders();
                headers.add(HttpHeaders.ACCESS_CONTROL_ALLOW_ORIGIN, requestHeaders.getOrigin());
                headers.addAll(HttpHeaders.ACCESS_CONTROL_ALLOW_HEADERS,
                        requestHeaders.getAccessControlRequestHeaders());
                if (requestMethod != null) {
                    headers.add(HttpHeaders.ACCESS_CONTROL_ALLOW_METHODS, requestMethod.name());
                }
                headers.add(HttpHeaders.ACCESS_CONTROL_ALLOW_CREDENTIALS, "true");
                headers.add(HttpHeaders.ACCESS_CONTROL_EXPOSE_HEADERS, "*");
                if (request.getMethod() == HttpMethod.OPTIONS) {
                    response.setStatusCode(HttpStatus.OK);
                    return Mono.empty();
                }
            }
            return chain.filter(ctx);
        };
    }
}

  3、相关链接

     https://blog.csdn.net/baidu_28068985/article/details/105558280