How to get body of a POST in php?

Question

I submit as POST to a php page the following:

{a:1}

This is the body of the request (a POST request).
In php, what do I have to do to

Answer 1

function getPost()
{
    if(!empty($_POST))
    {
        // when using application/x-www-form-urlencoded or multipart/form-data as the HTTP Content-Type in the request
        // NOTE: if this is the case and $_POST is empty, check the variables_order in php.ini! - it must contain the letter P
        return $_POST;
    }

    // when using application/json as the HTTP Content-Type in the request 
    $post = json_decode(file_get_contents('php://input'), true);
    if(json_last_error() == JSON_ERROR_NONE)
    {
        return $post;
    }

    return [];
}

print_r(getPost());