authentication - Angular 2: Get Authorization header

Question

in my App (Angular 2 / Ionic 2) I implemented my own login/authentication. Basically it works like this: On login, username and password is being validated by the PHP backend. A token is generated, which is sent back to then frontend in the header (Authorization). The response from backend looks like this:

HTTP/1.1 200 OK
Host: localhost:8080
Connection: close
X-Powered-By: PHP/5.6.28
Set-Cookie: PHPSESSID=jagagi2le1b8i7r90esr4vmeo6; path=/
Expires: Thu, 19 Nov 1981 08:52:00 GMT
Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Pragma: no-cache
Content-Type: application/json
 Authorization: d7b24a1643a61706975213306446aa4e4157d167eaad9aac989067a329c492d3
Access-Control-Allow-Origin: *
Access-Control-Allow-Headers: X-Requested-With, Content-Type, Accept, Origin, Authorization
Access-Control-Allow-Methods: GET, POST, PUT, DELETE, OPTIONS
Content-Length: 301

There's clearly an Authorization header with a token present. CORS seems also to be setup correctly, since I see Authorization in the Allow-Headers header.

But, when I try to get the header in Angular 2, it always returns null:

private extractDataAndSetAuthHeader(res: Response) {

    // Set auth header if available.
    // If not available - user is not logged in. Then 
    // we also have to remove the token from localStorage
    if(res.headers.has("Authorization"))
    {
        let token = res.headers.get("Authorization");

        this.setToken(token);
    }
    else
    {
        // If no token is sent, remove it
        this.removeToken();
    }

    let body = res.json();
    return body.data || { };
}

The first line of the method gives back false. Also, when I check the headers object in my response, it shows me only the following (Chrome dev tools):

[[Entries]]:
Array[4]
0:{"pragma" => Array[1]}
1:{"content-type" => Array[1]}
2:{"cache-control" => Array[1]}
3:{"expires" => Array[1]}

There's no Authorization header present in that object.

Can anyone please help me out?

Thanks in advance :)

Answer 1

Just wanted to post the answer as it might help others: The solution as to set

Access-Control-Expose-Headers: Authorization

Then - frontend can read the Authorization header as well.