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 {
    //這里為支持的請求頭，如果有自定義的header字段請自己添加（不知道為什么不能使用*）
    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);
        };
    }
    /**
    *
    *如果使用了注冊中心（如：Eureka），進行控制則需要增加如下配置
    */
    @Bean
    public RouteDefinitionLocator discoveryClientRouteDefinitionLocator(DiscoveryClient discoveryClient) {
        return new DiscoveryClientRouteDefinitionLocator(discoveryClient);
    }
}

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

@RestController
//實現(xiàn)跨域注解
//origin="*"代表所有域名都可訪問
//maxAge飛行前響應的緩存持續(xù)時間的最大年齡，簡單來說就是Cookie的有效期 單位為秒若maxAge是負數(shù),則代表為臨時Cookie,不會被持久化,Cookie信息保存在瀏覽器內存中,瀏覽器關閉Cookie就消失
@CrossOrigin(origins = "*",maxAge = 3600)
@RequestMapping("/album")
public class AlbumController {}

spring:
  application:
    name: system-gateway
  cloud:
    gateway:
      globalcors:
        cors-configurations:
          '[/**]': # 匹配所有請求
            allowedOrigins: "*" #跨域處理 允許所有的域
            allowedMethods: # 支持的方法
            - GET
            - POST
            - PUT
            - DELETE

default-filters:
      - AddResponseHeader=Access-Control-Allow-Credentials,true
      - AddResponseHeader=Access-Control-Allow-Headers,access-control-allow-origin
      - AddResponseHeader=Access-Control-Allow-Methods,GET
      - AddResponseHeader=Access-Control-Allow-Origin,*
      - AddResponseHeader=Access-Control-Allow-Age,3600

location /example {
   if ($request_method = 'OPTIONS') {
       add_header Access-Control-Allow-Origin *;
       add_header Access-Control-Max-Age 1728000;
       add_header Access-Control-Allow-Methods GET,POST,OPTIONS;
       add_header Access-Control-Allow-Headers  'DNT,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Range';
       add_header Content-Type' 'text/plain; charset=utf-8';
       add_header Content-Length 0 ;
       return 204;
    }
 
+   if ($http_origin ~* (https?://(.+\.)?(example\.com$))) {
+     add_header  Access-Control-Allow-Origin $http_origin;
+     add_header  Access-Control-Allow-Credentials true;
+     add_header  Access-Control-Allow-Methods GET,POST,OPTIONS;
+     add_header  Access-Control-Expose-Headers Content-Length,Content-Range;
+   }
 
    proxy_redirect off;
    proxy_set_header Host $host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_pass http://127.0.0.1:8080/;
   }