designcode / kohana-hooks

This module lets you register, observer and trigger custom hooks/events in your classes. It offers a functionality like WordPress hooks. Basically you can register a hook in your code and attach a handler with that hook. You can trigger the hook/event in your code where you want to.

kohana-hooks

This module lets you register, observer and trigger custom hooks/events in your classes. It offers a functionality like WordPress hooks. Basically you can register a hook in your code and attach a handler with that hook. You can trigger the hook/event in your code where you want to.

Overview

I was working on a big project where we had to perform several operations from different modules after user is created. Every developer would inject their code in my class and eventually user class became a mess and I ended up writing this class/module.

Getting Started

kohana-hooks works like any other Kohana Module. Just place the hook folder in modules folder and make sure you load this module in Kohana::module function.

Example Usage

• Register a hook

   Hooks::register('after_user_create', array('Email', 'send'));
  

• Trigger a hook

   Hooks::trigger('after_user_create', array('name'=>$user->name, 'email'=>$user->email));
  

• Alternatively, you can load all the hooks from a file saved in hook/hooks/ folder. You don't need to manually register and observe hooks if you use this method

   Hooks::load('my_hook_file');
  

Detailed Usage

Consider the class below

class User
{
	function __construct()
	{
		Hook::register('pre_user_create', array($this, 'pre_user_create'));
		Hook::register('post_user_create', array($this, 'post_user_create'));
	}

	public function create()
	{
		Hook::trigger('pre_user_create');

		// Code for user create goes here.

		Hook::trigger('post_user_create', array($user->id));
	}

	public function pre_user_create()
	{
		Log::add('Creating new user');
	}

	public function post_user_create($user_id)
	{
		Log::add('New user created, ID is: '.$user_id);
	}
}

In the contructor of above class, we registered two hooks pre_user_create and post_user_create with Hook::register. The first parameter tells the name of hook and the second parameter is the function we want to execute when this hook is triggered.

Now see the create method, for a programmer, the code is self explanatory. We triggered the hooks before and after creating user.

One thing important: The parameters you want to pass when triggering the hook, must be an array.

---

If you're super sensitive about your code like me and don't want anyone to edit your class. You can use the alternate method. Take a look at the following example

class User
{
	function __construct()
	{
		Hook::load('user');
	}

	public function create()
	{
		Hook::trigger('pre_user_create');

		// Code for user create goes here.

		Hook::trigger('post_user_create', array($user->id));
	}
}

Noticed the load method in User's constructor? This function will load and register the hooks from file hooks/user.php. It uses the Kohana's cascading filesystem, so you can put your hook files in application/hooks/.

The content of hooks/user.php would be

<?php defined('SYSPATH') or die('No direct script access.');

return array
(
	'pre_user_create' => array('SomeClass', 'SomeMethod'),
	'post_user_create' => function ($user_id) {
		Log::add('New user created, ID is: '.$user_id);
	}

);