通过跨域配置类解决跨域问题

问题：as been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource.

浏览器会发送一个option预检，请问是否可以跨域

解决方法1.使用nginx反向代理把请求都指向nginx 然后转发出去

             2.在网关项目里边定义一个跨域配置类

代码如下

package com.atguigu.gulimall.gateway.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;


@Configuration //这是一个配置类
public class GuliCorsConfiguration {
    @Bean //放入到容器中
    public CorsWebFilter corsWebFilter(){
        //配置跨域配置信息
        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
        CorsConfiguration corsConfiguration = new CorsConfiguration();
        //1.配置跨域

        corsConfiguration.addAllowedHeader("*");//允许所有头
        corsConfiguration.addAllowedMethod("*");//允许所有方法
        corsConfiguration.addAllowedOrigin("*");//允许所有来源
        corsConfiguration.setAllowCredentials(true);//允许携带cookie
        source.registerCorsConfiguration("/**",corsConfiguration);
        return new CorsWebFilter(source);
    }
}