$access_token = "xxxx";
$group_id = "xxxx";
$text = urlencode($data["#hello drugs!"]);
$secret="xxx";
$post = "wall.post?owner_id=-".$group_id."friends_only=0from_group=1message=".$text."signed=0access_token=".$access_token."v=5.52".$secret;
$sig = md5($post);
$sRequest = "https://api.vk.com/method/wall.post?owner_id=-".$group_id."&friends_only=0&from_group=1&message=".$text."&signed=0&access_token=".$access_token."&v=5.52&sig=".$sig;
var_dump($sRequest);
$oResponce = json_decode(file_get_contents($sRequest));
var_dump($oResponce);
/method/{Название метода}?{GET параметры}{POST параметры}