WEB 跨域/CORS 配置示例

server {
      listen 80; # 监听的端⼝
      server_name localhost; # 域名或ip
      location / { # 访问路径配置
        #允许跨域请求的域，* 代表所有
        add_header 'Access-Control-Allow-Origin' *;
        #允许带上cookie请求
        add_header 'Access-Control-Allow-Credentials' 'true';
        #允许请求的方法，比如 GET/POST/PUT/DELETE
        add_header 'Access-Control-Allow-Methods' *;
        #允许请求的header
        add_header 'Access-Control-Allow-Headers' *;

        if ($request_method = 'OPTIONS') {
          return204;
        }
        root /usr/share/nginx/html;# 根⽬录
        index index.html index.htm; # 默认⾸⻚
      }
      error_page 500 502 503 504 /50x.html; # 错误⻚⾯
      location = /50x.html {
        root html;
      }
}

#入口文件处添加
header("Access-Control-Allow-Origin: *");
header("Access-Control-Allow-Methods: *");

//1.导入模块
const express = require('express')
 
//2.创建服务器
let app = express()
// 导入一个cors(需要下载：这是给响应头设置res.setHeader("Access-Control-Allow-Origin", "*"))
 
var cors = require('cors')
app.use(cors())

const cors = require('koa2-cors');
const Koa = require('koa');

const app = new Koa();

app.use(cors({
  exposeHeaders: ['Authenticate'],
  credentials: true,
  allowMethods: ['GET', 'POST', 'DELETE', 'PUT', 'PATCH'],
  allowHeaders: ['Content-Type', 'Authorization', 'Accept'],
}));