Spring Cloud gateway 跨域问题

1、在和axios联调鉴权的时候发现，在增加自定义header的时候会出现跨域问题

2、因为是跨域请求，前端会首先发送一个options的嗅探请求，一次真正的请求 所以会出现两个403

3、网关之前设置的是全局filter

刚开始看了

package com.xxx.filter;
 
import com.alibaba.fastjson.JSONObject;
import com.xxx.common.constant.SeparationStr;
import com.xxx.common.constants.Rediskeyss;
import com.xxx.common.constants.SessionConstant;
import com.xxx.common.rest.model.resp.SimpleResult;
import com.xxx.common.utils.RedisUtil;
import com.xxx.common.utils.TokenUtil;
import org.apache.commons.lang.StringEscapeUtils;
import org.reactivestreams.Publisher;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.core.Ordered;
import org.springframework.core.io.buffer.DataBuffer;
import org.springframework.core.io.buffer.DataBufferFactory;
import org.springframework.core.io.buffer.DataBufferUtils;
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.http.server.reactive.ServerHttpResponseDecorator;
import org.springframework.stereotype.Component;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;
 
import java.nio.charset.Charset;
 
/**
 * @ClassName WrapperResponseGlobalFilter
 * @Description 全局过滤器，用来修改response和处理数据
 * @Date 2019/8/28 9:46
 **/
 
@Component
public class WrapperResponseGlobalFilter implements GlobalFilter, Ordered {
 
 
    private static final String ALL = "*";
    private static final String MAX_AGE = "18000L";
 
 
    @Override
    public Mono<Void> filter(ServerWebExchange serverWebExchange, GatewayFilterChain gatewayFilterChain) {
        ServerHttpRequest request = serverWebExchange.getRequest();
//        if (!CorsUtils.isCorsRequest(request)) {
//            return gatewayFilterChain.filter(serverWebExchange);
//        }
        ServerHttpResponse response = serverWebExchange.getResponse();
        HttpHeaders headers = response.getHeaders();
        headers.add(HttpHeaders.ACCESS_CONTROL_ALLOW_ORIGIN, "*");
        headers.add(HttpHeaders.ACCESS_CONTROL_ALLOW_METHODS, "POST, GET, PUT, OPTIONS, DELETE, PATCH");
        headers.add(HttpHeaders.ACCESS_CONTROL_ALLOW_CREDENTIALS, "true");
        headers.add(HttpHeaders.ACCESS_CONTROL_ALLOW_HEADERS, "*");
        headers.add(HttpHeaders.ACCESS_CONTROL_EXPOSE_HEADERS, ALL);
        headers.add(HttpHeaders.ACCESS_CONTROL_MAX_AGE, MAX_AGE);
        if (request.getMethod() == HttpMethod.OPTIONS) {
            response.setStatusCode(HttpStatus.OK);
            return Mono.empty();
        }
        return gatewayFilterChain.filter(serverWebExchange);
    }
 
    @Override
    public int getOrder() {
        return -2;
    }
 
}

然而并木有什么卵用，各位大兄弟们，为什么都喜欢复制粘贴啊？害人害己啊！

看起来没问题，但在前端请求的时候根本就没有进入到这里，就直接拒绝了。

之后又想了下是否是容器层给拒绝了，由于gateway确实用的人比较少，百度了半天都是互相抄的文章，半天有用的没有，只能采用老的办法了。结果发现根源在Webflux上边，由于gateway使用的是webflux，而不是springmvc，从gateway的filter里边设置cors就行了。

package com.xxx.config;
 
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.cors.CorsConfiguration;
import org.springframework.web.cors.reactive.CorsWebFilter;
import org.springframework.web.cors.reactive.UrlBasedCorsConfigurationSource;
import org.springframework.web.util.pattern.PathPatternParser;
 
/**
 * @ClassName CorsConfig
 * @Description gateway跨域配置
 * @Date 2019/9/5 14:00
 **/
 
@Configuration
public class CorsConfig {
 
    @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);
    }
}

真心希望大家不要随便 copy ，亲自验证过再发出来分享撒。

我是进阶的球儿，大家一起2019年的爬坑历程。感觉分享很给力的话给个赞，谢谢！！！有问题也可以下方留言沟通。