README

Simplex

Simplex is a Pimple 3 fork with full PSR-11 compliance and cross-framework service-provider support.

Simplex is a small dependency injection container for PHP.

Differences with Pimple

Simplex is a fork of Pimple's code. The only differences are the following:

• Simplex\Container implements ContainerInterface, which means the following methods exist:
  • $container->get($id) which is an alias to $container[$id]
  • $container->has($id) which is an alias to isset($container[$id])
• for symmetry reasons, Simplex\Container also provides an additional method:
  • $container->set($id, $value) which is an alias to $container[$id] = ...
• the constructor takes an optional ContainerInterface $rootContainer = null argument to support the delegate lookup feature: if provided, this container will be injected in factories instead
• service providers have been completely replaced by container-interop's service providers: that allows to load cross-framework modules in this container
• it is possible to extend a scalar value with $container->extend() (for compatibility reasons with cross-framework service providers)

Below is the documentation of Pimple/Simplex.

Installation

composer require mnapoli/simplex

Usage

Creating a container is a matter of creating a Container instance:

$container = new \Simplex\Container();

Defining Services

A service is an object that does something as part of a larger system. Examples of services: a database connection, a templating engine, or a mailer. Almost any global object can be a service.

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

// define some services
$container['session_storage'] = function ($c) {
    return new SessionStorage('SESSION_ID');
};

$container['session'] = function ($c) {
    return new Session($c['session_storage']);
};

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

As objects are only created when you get them, the order of the definitions does not matter.

Using the defined services is also very easy:

// get the session object
$session = $container['session'];

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

Defining Factory Services

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

$container['session'] = $container->factory(function ($c) {
    return new Session($c['session_storage']);
});

Now, each call to $container['session'] returns a new instance of the session.

Defining Parameters

Defining a parameter allows to ease the configuration of your container from the outside and to store global values:

// define some parameters
$container['cookie_name'] = 'SESSION_ID';
$container['session_storage_class'] = 'SessionStorage';

If you change the session_storage service definition like below:

$container['session_storage'] = function ($c) {
    return new $c['session_storage_class']($c['cookie_name']);
};

You can now easily change the cookie name by overriding the session_storage_class parameter instead of redefining the service definition.

Protecting Parameters

Because Pimple sees anonymous functions as service definitions, you need to wrap anonymous functions with the protect() method to store them as parameters:

$container['random_func'] = $container->protect(function () {
    return rand();
});

Modifying Services after Definition

In some cases you may want to modify a service definition after it has been defined. You can use the extend() method to define additional code to be run on your service just after it is created:

$container['session_storage'] = function ($c) {
    return new $c['session_storage_class']($c['cookie_name']);
};

$container->extend('session_storage', function ($storage, $c) {
    $storage->...();

    return $storage;
});

The first argument is the name of the service to extend, the second a function that gets access to the object instance and the container.

Service providers

Simplex supports registering cross-framework service providers.

To register service providers, pass an array of service providers as first constructor argument.

$container = new \Simplex\Container([new MyServiceProvider()]);