package cn.huge.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.codec.ServerCodecConfigurer;
import org.springframework.http.codec.support.DefaultServerCodecConfigurer;
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;

/**
 * @title: 网关cors配置
 * @description: 网关cors配置
 * @company: hugeinfo
 * @author: liyj
 * @time: 2021-11-05 16:51:48
 * @version: 1.0.0
 */
@Configuration
public class CorsConfig {

    private static final String MAX_AGE = "18000L";

    @Bean
    public WebFilter corsFilter() {
        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, "*");
                headers.add(HttpHeaders.ACCESS_CONTROL_MAX_AGE, MAX_AGE);
                if (request.getMethod() == HttpMethod.OPTIONS) {
                    response.setStatusCode(HttpStatus.OK);
                    return Mono.empty();
                }

            }
            return chain.filter(ctx);
        };
    }

    @Bean
    public ServerCodecConfigurer serverCodecConfigurer() {
        return new DefaultServerCodecConfigurer();
    }
}
/**
 * -------------------_ooOoo_-------------------
 * ------------------o8888888o------------------
 * ------------------88" . "88------------------
 * ------------------(| -_- |)------------------
 * ------------------O\  =  /O------------------
 * ---------------____/`---'\____---------------
 * -------------.'  \\|     |//  `.-------------
 * ------------/  \\|||  :  |||//  \------------
 * -----------/  _||||| -:- |||||-  \-----------
 * -----------|   | \\\  -  /// |   |-----------
 * -----------| \_|  ''\---/''  |   |-----------
 * -----------\  .-\__  `-`  ___/-. /-----------
 * ---------___`. .'  /--.--\  `. . __----------
 * ------."" '<  `.___\_<|>_/___.'  >'"".-------
 * -----| | :  `- \`.;`\ _ /`;.`/ - ` : | |-----
 * -----\  \ `-.   \_ __\ /__ _/   .-` /  /-----
 * ======`-.____`-.___\_____/___.-`____.-'======
 * -------------------`=---='
 * ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 * ---------佛祖保佑---hugeinfo---永无BUG----------
 */