Driver - CodeIgniter Example

CodeIgniter provides a way to group related functionality into sets, which can be organized into "drivers". A driver is a set of related functionality that can be easily swapped out for another implementation. This allows CodeIgniter to provide a flexible architecture that can be extended in a modular way.

Syntax

A CodeIgniter driver can be created using the following syntax:

class My_driver extends CI_Driver_Library {
    protected $valid_drivers = array('driver1', 'driver2');

    public function __construct() {
        parent::__construct();

        // Additional initialization code here
    }

    public function some_method() {
        // Implementation here
    }
}

Example

Suppose we have a system for sending notifications via multiple channels, such as email and SMS. We can create a driver to handle each channel, and then group them together into a Notifier driver:

class Email_notifier extends CI_Driver {
    public function send_notification($recipient, $message) {
        // Email implementation here
    }
}

class Sms_notifier extends CI_Driver {
    public function send_notification($recipient, $message) {
        // SMS implementation here
    }
}

class Notifier extends CI_Driver_Library {
    protected $valid_drivers = array('email_notifier', 'sms_notifier');

    public function send_notification($recipient, $message) {
        // Delegate to the active driver
        $this->{$this->active_driver}->send_notification($recipient, $message);
    }
}

Then, we can use the Notifier driver to send notifications, without worrying about the details of the underlying implementation:

// Load the notifier driver
$this->load->driver('notifier');

// Send an email notification
$this->notifier->email_notifier->send_notification('john@example.com', 'Hello, John!');

// Send an SMS notification
$this->notifier->sms_notifier->send_notification('555-1234', 'Hello, world!');

Explanation

In the above example, we create two drivers (Email_notifier and Sms_notifier) to handle notifications via email and SMS. Then, we create a Notifier driver, which groups together the other two drivers. The Notifier driver also provides a common interface (send_notification()), which can be used to send notifications without worrying about the underlying implementation.

To use the Notifier driver, we load it with the load->driver() method and then access the appropriate methods using dot notation. CodeIgniter determines which driver to use based on the configuration or other criteria, such as user input.

Use

CodeIgniter drivers are a powerful way to organize related functionality into modular, reusable components. Drivers can be swapped in and out to change the implementation of a particular feature without affecting other parts of the system. Driver libraries can be loaded and used in a similar way to other CodeIgniter libraries, with access to the underlying driver objects via dot notation.

Important Points

• Drivers are a powerful way to organize related functionality into modular, reusable components.
• A driver is a class that implements a common interface, and is designed to be interchangeable with other implementations.
• Driver libraries provide a way to easily load and access driver objects.
• Drivers can be used to implement pluggable functionality, such as different methods for sending notifications or handling authentication.

Summary

CodeIgniter provides a flexible system for organizing related functionality into drivers. Drivers can be easily swapped in and out to change the implementation of a particular feature without affecting other parts of the system. Driver libraries provide a way to easily load and access driver objects, which can be used to implement pluggable functionality. By using drivers, developers can create modular, reusable components that can be extended and customized as needed.