要修复Node.js应用程序中的跨源请求问题:

npm i cors

然后简单地将下面的代码添加到app.js文件中:

let cors = require('cors')
app.use(cors())

我的“API服务器”是一个PHP应用程序，所以为了解决这个问题，我发现下面的解决方案可以工作:

将这些行放入index.php文件中:

header('Access-Control-Allow-Origin: *');
header('Access-Control-Allow-Methods: GET, POST, PATCH, PUT, DELETE, OPTIONS');
header('Access-Control-Allow-Headers: Origin, Content-Type, X-Auth-Token');

禁用Chrome安全。

创建Chrome快捷方式:右键单击→属性→目标。"C:\Program Files (x86)\谷歌\Chrome\Application\ Chrome .exe"——disable-web-security——user-data-dir=" C: /chromedev"

在我的Apache VirtualHost配置文件中，我添加了以下几行:

Header always set Access-Control-Allow-Origin "*"
Header always set Access-Control-Allow-Methods "POST, GET, OPTIONS, DELETE, PUT"
Header always set Access-Control-Max-Age "1000"
Header always set Access-Control-Allow-Headers "x-requested-with, Content-Type, origin, authorization, accept, client-security-token"

RewriteEngine On
RewriteCond %{REQUEST_METHOD} OPTIONS
RewriteRule ^(.*)$ $1 [R=200,L]

解决这个问题很简单，只需要几个步骤，不用担心任何事情。

请遵循以下步骤来解决它。

open (https://www.npmjs.com/package/cors#enabling-cors-pre-flight) go to installation and copy the command npm install cors to install via Node.js in a terminal go to Simple Usage (Enable All CORS Requests) by scrolling. Then copy and paste the complete declaration in your project and run it...that will work for sure... copy the comment code and paste in your app.js or any other project and give a try...this will work. This will unlock every cross origin resource sharing...so we can switch between servers for your use

我正在使用AWS SDK进行上传，在花了一些时间在网上搜索之后，我偶然发现了这个问题。多亏了@lsimoneau 45581857，原来发生了完全相同的事情。

我只是通过附加区域选项将请求URL指向bucket上的区域，它就工作了。

 const s3 = new AWS.S3({
 accessKeyId: config.awsAccessKeyID,
 secretAccessKey: config.awsSecretAccessKey,
 region: 'eu-west-2'  // add region here });