How to send CORS request from React? - reactjs

Question

I have problem with sending CORS request with token in header.
Fetch code:
fetchApi() {
fetch('http://some-link.com',
{
headers: {
'Accept': 'application/json',
'auth-token': 'xxxxxxxxx'
},
method: "GET"
}).then(response => response.json())
.then(function(response){
this.setState({hits:response});
}).catch(function(error) { console.log(error); });
console.log(this.state.hits);
};
Console log:
Access to fetch at 'http://some-link.com' from origin 'http://localhost:3000' has been blocked by CORS policy: Request header field auth-token is not allowed by Access-Control-Allow-Headers in preflight response.
Network request log:
General
Request URL: http://some-link.com
Request Method: OPTIONS
Status Code: 200 OK
Remote Address: some_ip:80
Referrer Policy: no-referrer-when-downgrade
Response Headers
Access-Control-Allow-Headers: origin, x-requested-with, content-type, auth_token
Access-Control-Allow-Methods: POST, GET, PUT, DELETE, OPTIONS
Access-Control-Allow-Origin: *
Cache-Control: no-cache, private
Connection: Keep-Alive
Content-Length: 8
Content-Type: application/json
Date: Tue, 13 Nov 2018 13:30:35 GMT
Keep-Alive: timeout=5, max=100
Server: Apache/2.4.10 (Debian)
Request Headers
Provisional headers are shown
Access-Control-Request-Headers: auth-token
Access-Control-Request-Method: GET
Origin: http://localhost:3000
Referer: http://localhost:3000/
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.77 Safari/537.36
Any ideas what might be wrong?

Answer 1

You have to change the server settings to allow the header "auth-token".
Once you do this, your request will work.
You are currently allowing "auth_token", not "auth-token".
Alternatively, change the header name in the frontend like so:
headers: {
'Accept': 'application/json',
'auth_token': 'xxxxxxxxx'
}