CORS HEADER 'ACCESS-CONTROL-ALLOW-ORIGIN' MISSING IN SLIM/ANGULARJS STACK

I have been tinkering with angularJS in production mode and got this annoying error,that got me stuck for days at the expense of my other projects.cross-origin request blocked: the same origin policy disallows reading the remote resource at http://veranevents.com........ (reason: cors header 'access-control-allow-origin' missing).
I also had error code 500 from my server when i looked at networks in console mode.
My development stack was just a simple configuration of

1. LAMP SERVERS 
2. slim php v2 
3.  angularjs 1.5

To solve the errors.I saved my api in another file and deleted the whole darn thing and from the top started  adding call after call:
I also added this piece of code  to solve the CORS problem

    if (isset($_SERVER['HTTP_ORIGIN'])) {
        header("Access-Control-Allow-Origin: {$_SERVER['HTTP_ORIGIN']}");
        header('Access-Control-Allow-Credentials: true');
        header('Access-Control-Max-Age: 86400');    // cache for 1 day
    }

    // Access-Control headers are received during OPTIONS requests
    if ($_SERVER['REQUEST_METHOD'] == 'OPTIONS') {

        if (isset($_SERVER['HTTP_ACCESS_CONTROL_REQUEST_METHOD']))
            header("Access-Control-Allow-Methods: GET, POST, OPTIONS");        

        if (isset($_SERVER['HTTP_ACCESS_CONTROL_REQUEST_HEADERS']))
            header("Access-Control-Allow-Headers: {$_SERVER['HTTP_ACCESS_CONTROL_REQUEST_HEADERS']}");

        exit(0);
    }

Thanks to a couple of guys at stackover flow
I realized that i had several syntatic errors,that were transparent on my local server and that got rid all the errors,which then made my day.
Head over to  Veran events management software   and see my angularjs web app