Untitled

<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN"><html><head><title>201 Created</title></head><body><h1>TGT Created</h1><form action="https://xxx.xxxx.xxx/cas/v1/tickets/TGT-70-fd5AmiAKLQXqarzBy19w5FMpyKbN4eaMoGbSdmrhfZwiSDG5Nj-cas" method="POST">Service:<input type="text" name="service" value=""><br><input type="submit" value="Submit"></form></body></html>

authenticate(user: string, pass: string): Observable<string> {
    var auth_url = 'https://xxx.xxx/tickets';
    var creds = "username=" + user + "&password=" + pass;
    var headers = new Headers();
    headers.append('Content-Type', 'application/x-www-form-urlencoded');

    return this.http.post(auth_url, creds, { headers: headers })
    .map(response => {
      let token = response.json();
      if(!token) {
        this.setTokenInLocalStorage(response.json(), user);
        this.store.dispatch(this.actions.logIn(response.json()));
        return token;
      }
      else {
        return null;
      }
    });
  }