Pimple.js ( inspired by https://github.com/fabpot/Pimple )

Pimple.js is a small Dependency Injection Container for Javascript that consists of just one file and one class (about 50 lines of code).

Download it, require it in your code, and you're good to go:

<script type="text/javascript" src="path/to/pimple.js"></script>

Creating a container is a matter of instating the Pimple class:

container = new Pimple();

As many other dependency injection containers, Pimple is able to manage two different kind of data: objects and parameters.

Defining Parameters

Defining a parameter is as simple as using the Pimple instance as an array:

// define some parameters
container.set('cookie_name, 'SESSION_ID');
container.set('session_storage_class', 'SessionStorage');

Defining Objects

Objects are defined by anonymous functions that return an instance of the object:

// define some objects
container.set('session_storage', function (c) {
    return new c.get('session_storage_class')(c.get('cookie_name'));
});

container.set('session',  function (c) {
    return new Session(c.get('session_storage'));
});

Notice that the anonymous function has access to the current container instance, allowing references to other objects or parameters.

As objects are only created when you get them, the order of the definitions does not matter, and there is no performance penalty.

Using the defined objects is also very easy:

// get the session object
session = container.get('session');

// the above call is roughly equivalent to the following code:
// storage = new SessionStorage('SESSION_ID');
// session = new Session(storage);

Defining Shared Objects

By default, each time you get an object, Pimple returns a new instance of it. If you want the same instance to be returned for all calls, wrap your anonymous function with the share() method:

c.set('session',  c.share(function (c) {
    return new Session(c.get('session_storage'));
}));

Protecting Parameters

As Pimple makes no difference between a parameter and an object, you can use the protect() method if you need to define a parameter as an anonymous function:

c.set('random',c.protect(function () { return rand(); }));