Request header field Access-Control-Allow-Headers is not allowed by Access-Control-Allow-Headers

Question

I\'m trying to send files to my server with a post request, but when it sends it causes the error:

Request header field Content-Type is not allowed by

Answer 1

this is backend problem. if use sails api on backend change cors.js and add your filed here

module.exports.cors = {
  allRoutes: true,
  origin: '*',
  credentials: true,
  methods: 'GET, POST, PUT, DELETE, OPTIONS, HEAD',
  headers: 'Origin, X-Requested-With, Content-Type, Accept, Engaged-Auth-Token'
};

Answer 2

Request header field Access-Control-Allow-Origin is not allowed by Access-Control-Allow-Headers error means that Access-Control-Allow-Origin field of HTTP header is not handled or allowed by response. Remove Access-Control-Allow-Origin field from the request header.

Answer 3

If you are using localhost and PHP set to this to solve the issue:

header('Access-Control-Allow-Origin: *');
header('Access-Control-Allow-Headers: Content-Type'); 

From your front-end use:

{headers: {"Content-Type": "application/json"}}

and boom no more issues from localhost!