Zit is a simple dependency injector based heavily on Pimple. It aims to provide the same simplicity as Pimple while offering a slightly more robust object interface.
Zit is simple to use. Just include it and create a new container:
<?php
require_once '/path/to/lib/Zit/Container.php';
$container = new \Zit\Container();
?>
Like Pimple, objects are defined through anonymous functions that return an instance of the object:
<?php
$container->set('auth', function() {
return new Auth();
});
?>
All instantiation functions are passed the container as the first argument, making dependency injection possible:
<?php
$container->set('auth', function($container) {
return new Auth($container->get('db'));
});
?>
Zit also provides convenient magic methods for setting instantiation functions:
<?php
$container->setAuth(function() { // ... }); // Or:
$container->set_auth(function() { // ... });
?>
Getting objects are as simple as:
<?php
$container->get('auth');
?>
Or, if you prefer the shorthand:
<?php
$container->getAuth(); // Or:
$container->get_auth();
?>
By default, all objects are shared in Zit. That is, once an object is created, that same exact object is returned for each additional get(). If you need a fresh object, you can do so with:
<?php
$container->fresh('auth'); // Or:
$container->freshAuth(); // Or:
$container->fresh_auth(); // Or:
$container->newAuth(); // Or:
$container->new_auth();
?>
Note the because the 'new' keyword is reserved, you can only use it if you're using the magic methods.
Sometimes you need to pass parameters to the constructor of an object, while still also injecting dependencies. Zit automatically passes all parameters on to your instantiation function:
<?php
$container->setUser(function($c, $id)) {
$user = new User($id);
$user->setDb($c->getDb());
return $user;
});
$user = $container->newUser(1);
?>
You can also use Zit to store non-objects (anything from a string to an anonymous function). Just use the setParam() method:
<?php
$container->setParam('api_key', 'abcd1234567890');
$key = $container->get('api_key');
?>
Most projects will benefit from a custom container that sets up its own injection rules. This is as simple as extending Zit:
<?php
namespace MyApp\Di;
class Container extends \Zit\Container
{
public function __construct()
{
$this->setAuth(function() { // ... });
$this->setUser(function() { // ... });
}
}
?>