PHP - authentication troubles

API
4

I took a look at my working code now that I have access to it and it seems I was incorrect earlier about the data needing to be GET params like the docs say (I’m not even sure GET params work, maybe @DallasNChains can confirm).

Working code I have tucked away:

function api_call(string $url, array $data = []) {
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);

    curl_setopt($ch, CURLOPT_POST, 1);
    $postdata = http_build_query($data);
    curl_setopt($ch, CURLOPT_POSTFIELDS, $postdata);

    $output = curl_exec($ch);
    $e = curl_error($ch);
    if ($e) {
        die('FATAL ERROR');
    }
    curl_close($ch);
    return $output;
}

if (array_key_exists('code', $_GET)) {
    $oauth_info = api_call('https://api.twitch.tv/kraken/oauth2/token', [
        'client_id' => $CLID,
        'client_secret' => $SECRET,
        'grant_type' => 'authorization_code',
        'redirect_uri' => urldecode($REDIRURI), // my $REDIRURI is stored urlencoded due to being used that way more times
        'code' => $_GET['code']
    ]);
    $oauth = json_decode($oauth_info, true);
}