PHP Reading raw POST data
Usually data sent in a POST request is structured key/value pairs with a MIME type of application/x-www-formurlencoded. However many applications such as web services require raw data, often in XML or JSON format, to be sent instead. This data can be read using one of two methods.
php://input is a stream that provides access to the raw request body.
$rawdata = file_get_contents("php://input");
// Let's say we got JSON
$decoded = json_decode($rawdata);Version < 5.6
$HTTP_RAW_POST_DATA is a global variable that contains the raw POST data. It is only available if the always_populate_raw_post_data directive in php.ini is enabled.
$rawdata = $HTTP_RAW_POST_DATA;
// Or maybe we get XML
$decoded = simplexml_load_string($rawdata);This variable has been deprecated since PHP version 5.6, and was removed in PHP 7.0. Note that neither of these methods are available when the content type is set to multipart/form-data, which is used for file uploads.
Reading POST data
Data from a POST request is stored in the superglobal $_POST in the form of an associative array.
Note that accessing a non-existent array item generates a notice, so existence should always be checked with the isset() or empty() functions, or the null coalesce operator.
Example:
$from = isset($_POST["name"]) ? $_POST["name"] : "NO NAME";
$message = isset($_POST["message"]) ? $_POST["message"] : "NO MESSAGE";
echo "Message from $from: $message";Version ≥ 7.0
$from = $_POST["name"] ?? "NO NAME";
$message = $_POST["message"] ?? "NO MESSAGE";
echo "Message from $from: $message";Reading GET data
Data from a GET request is stored in the superglobal $_GET in the form of an associative array.
Note that accessing a non-existent array item generates a notice, so existence should always be checked with the isset() or empty() functions, or the null coalesce operator.
Example: (for URL /topics.php?author=alice&topic=php)
$author = isset($_GET["author"]) ? $_GET["author"] : "NO AUTHOR";
$topic = isset($_GET["topic"]) ? $_GET["topic"] : "NO TOPIC";
echo "Showing posts from $author about $topic";Version ≥ 7.0
$author = $_GET["author"] ?? "NO AUTHOR";
$topic = $_GET["topic"] ?? "NO TOPIC";
echo "Showing posts from $author about $topic";