Shed

Dependency Injection container.

First version of this library was written in 2007. This is PHP 5.3 version extracted from some of my projects.

Definition

All container variables are defined via simple associative array. You can set any value, either scalar values (booleans, integers, floats, strings) and compound values (arrays, objects).

array(
  'bool' => true,
  'int' => 5,
  'float' => 1.2345,
  'string' => 'string',
  'array' => array(1, 2, 3),
  'object' => new SampleObject(),
)

Shed supports lazy loading, which means the initialization of an object is delayed until the first time it is needed.

Definitions are marked with Container::DEFINITION set as first element of array.

array(
  'lazy_object' => array(
    Container::DEFINITION,
    'class' => 'LazyObject',
    'args' => array(4, 5)
  )
)

References

Any variable can be injected anywhere you want: constructors arguments, methods arguments, etc. Reference is indicated by ampersand sign (&) at the beginning.

array(
  'injected_object' => array(
    Container::DEFINITION,
    'class' => 'InjectedObject',
  ),
  'lazy_object' => array(
    Container::DEFINITION,
    'class' => 'LazyObject',
    'methods' => array(
      array('name' => 'inject', 'args' => array('&injected_object')),
    ),
  ),
)

Definition options

Possible options: class, callback, args, methods (name, args), properties (name, value), files.

files

Files to require. Useful if proper autoloading callback is not registered.

'object' => array(
  Container::DEFINITION,
  'class' => 'SampleObject',
  'file' => __DIR__.'/classes/SampleObject.php'
)

class

Class name of object to be initialized on call.

'object' => array(
  Container::DEFINITION,
  'class' => 'SampleObject',
)

callback

Function.

  'callback' => array(
	  Container::DEFINITION,
	  'callback' => 'floor',
	  'args' => array(4.89)
  )

Callback with reference (call to object's method).

  'callback_with_ref' => array(
	  Container::DEFINITION,
	  'callback' => array('&object', 'createObject')
  )

Singleton.

  'singleton' => array(
 	  Container::DEFINITION,
	  'callback' => array('SingletonObject', 'getInstance')
  )

args

Either construct arguments or callback arguments.

  'object' => array(
	  Container::DEFINITION,
	  'class' => 'SampleObject',
	  'args' => array('val1', 'val2')
  ),

methods

Methods to call right after initialization.

'object' => array(
	Container::DEFINITION,
	'class' => 'SampleObject',
	'methods' => array(
  array('name' => 'setArg', 'args' => array('val1')),
  array('name' => 'setArg', 'args' => array('val2')),
	)
)

properties

Properties to be set right after initialization.

'object' => array(
	Container::DEFINITION,
	'class' => 'SampleObject',
	'properties' => array(
  array('name' => 'arg', 'value' => 'val')
	)
)

Usage

Shed extends ArrayObject, thus makes possible to access variables multiple ways.

$container = new \Shed\Container();
$container->var;
$container['var'];
$container->getVar();