The Compat Package

This is a simple package that contains forward compatibility classes and interfaces that are registered to the global namespace


JsonSerializable is a PHP 5.4 interface that allows you to specify what data to serialize to JSON when you json_encode an object that implements the interface.


Since this is a PHP 5.4 interface, the jsonSerialize() method does not get called automatically when json_encode-ing an instance of the class when used in 5.3. To work around this, simply call the jsonSerialize() method directly when passing it to json_encode. This is forward-compatible with PHP 5.4.

Note in some instances of PHP 5.5 from Debian the interface is also missing (see which will also require this interface to be included.

class MyClass implements \JsonSerializable
     * @var  array  Holds the data this class uses.
    protected $data;

    public function __construct(array $data)
        $this->data = $data;

    public function jsonSerialize()
        return $this->data;

$obj = new MyClass(array('sample', 'data', 'to', 'encode'));

$encoded = json_encode($obj->jsonSerialize());

Installation via Composer

Add "joomla/compat": "~1.0" to the require block in your composer.json and then run composer install.

    "require": {
        "joomla/compat": "~1.0"

Alternatively, you can simply run the following from the command line:

composer require joomla/compat "~1.0"