user3194367 user3194367 - 1 year ago 137
Javascript Question

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

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 Access-Control-Allow-Headers.

So I googled the error and added the headers:

$$rootScope.URL, {params: arguments}, {headers: {
"Access-Control-Allow-Origin" : "*",
"Access-Control-Allow-Methods" : "GET,POST,PUT,DELETE,OPTIONS",
"Access-Control-Allow-Headers": "Content-Type, Access-Control-Allow-Headers, Authorization, X-Requested-With"

Then I get the error:

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

So I googled that and the only similar question I could find was provided a half answer then closed as off topic. What headers am I supposed to add/remove?

Answer Source

The server (that the POST request is sent to) needs to include the Access-Control-Allow-Headers header (etc) in its response. Putting them in your request from the client has no effect.

This is because it is up to the server to specify that it accepts cross-origin requests (and that it permits the Content-Type request header, and so on) – the client cannot decide for itself that a given server should allow CORS.