README

Dependency injection container class for php. Extends kris-ro/php-config functionality and relies on it for configuration.

Installation

Use composer to install PHP Dependency Injection Container.

composer require kris-ro/php-dependency-injection

Configuration

The Container reads the definitoin for the requested service from the config array built by Container::buildConfig().
All services must be defined in the services branch of the configuration array. Each service is identified by its service idendifier (service_identifier in the example below).
First key in the definition array must be the class containing the class name prefixed by the namespace and optionally sufixed with the method name. Valid examples:

{
  "services" : {
    "service_identifier" : {
      "class" : "\\Class\\With\\Namespace"
    },
    "another_service_identifier" : {
      "class" : "\\Class\\With\\Namespace::MethodName"
    }
  }
}

The class can be followed by other entries in the definition array representing the methods of the created service that will be executed (in the same order as they are listed in the definition) by the container before the service is delivered. Valid examples:

{
  "services" : {
    "myPDO" : {
      "class": "\\PDO",
      "_construct": {
        "dsn": "mysql:host=localhost;dbname=test",
        "username": "k",
        "password": "123456"
      }
    },
    "validator" : {
      "class": "\\KrisRo\\Validator\\Validator",
      "createRegexRules" : {
        "rules": {
          "alphanumeric": "/^[a-z0-9\\-_]+$/i"
        }
      }
    }
  }
}

As you can see above, for myPDO the _construct is specified because it needs those three arguments.
The second definition validator also specifies a method to be executed with one argument rules.

The names of the arguments in the definition are taken from the method.
If you look at the PDO definition above you'll see that _constructor has three arguments dsn, username and password that are maped to PDO's constructor arguments $pdo, $username and $password respectively.

There are three types of argument values:

• a service identifier prefixed with the character @
• an entry path from the config array prefixed with the character #
• anything else is passed as is

Service as argument
Value of credentialsOrPDO references myPDO service.

{
  "services" : {
    "myPDO" : {
      "class": "\\PDO",
      "_construct": {
        "dsn": "mysql:host=localhost;dbname=test",
        "username": "k",
        "password": "123456"
      }
    },
    "model" : {
      "class": "\\KrisRo\\PhpDatabaseModel\\Model",
      "_construct": {
        "credentialsOrPDO": "@myPDO"
      }
    }
  }
}

Entry path from config array
Value of rules references validator > rules entry in configuration array.

{
  "validator" : {
    "rules": {
      "alphanumeric": "/^[a-z0-9\\-_]+$/i"
    }
  },
  "services" : {
    "validator": {
      "class": "\\KrisRo\\Validator\\Validator",
      "_construct": {
        "rules": "#validator/rules"
      }
    }
  }
}

Usage

Once the service is defined it is as simple as:

use KrisRo\PhpDependencyInjection\Container;

# first build the configuration array. See more at https://github.com/kris-ro/php-config
Container::buildConfig('/absolute/path/to/your/folder/with/json/files');

# load the service you need
$pdo = Container::service('myPDO');
$model = Container::service('model');
$validator = Container::service('validator');