The Bakery Everything CakePHP

An article on how to cache an element has been published earlier on bakery at http://bakery.cakephp.org/articles/view/optimizing-your-cakephp-elements-and-views-with-caching. This article is an enhancement to the above mentioned article. So make sure you are through with the other one before getting on this.

There are many situations where you would want to cache an element individually for each user. Cases like having separate tagClouds, todolists, etc for each user. Remember, if you are calling 'requestAction' in your elements then it may be a good idea to cache the element as sometimes 'requestAction' could get expensive with lots of them.

For this article, I will assume that we are having a todo element as follows:

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// Todo Element

$todoLists = $this->requestAction('todoLists/getList');


echo '<h2>ToDo List</h2>';
echo '<ul>';

foreach($todoLists as $todoList)
{
   echo '<li>'.$todoList['name'].'</li>';
}
echo '</ul>';


And in one of my views I call this element as follows:

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// Generic way to cache element
$this->element('todo', array('cache'=>'+1 day'));


If I call element using the above call, what happens is that Cake will cache the element 'todo' as app/tmp/cache/views/element__todo for 1 day. But this cache will be same for all users as the name of the element and cache file generated is the same.

First you must understand how the cache file for element is named. It is as 'element_{plugin}_{name of element}'. In our case, as we didnot specify the plugin, it was considered null, and you see two consecutive 'underscores' in the name of the cache file (element__todo).

Taking the naming convention to our advantage, we trick Cake to do our job. Take a look at following code:
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// Individually cache the element for each user.
$userId = 3; // For example
$this->element('todo', array('cache'=>'+1 day', 'plugin'=>$userId));


Woila, you are done. You just tricked Cake to create a separate cache
file for each user. By specifying the plugin to be userId, Cake
creates a separate cache file with the name 'element_3_todo'.

So now for each user, cake will create a separate cache file. Hang on,
don't you want to know how to delete this cache file if the user
updated his todo list?? In your TodoList Model, update the afterSave
method as follows

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function afterSave()
{
  $userId = $this->data['TodoList']['user_id'];
  $this->clearCache('element_'.$userId.'_todo', 'views', '');
  parent::afterSave();
}


That's it, whenever user updates the todo list, cake will now
automatically clear the cache for that user.

This is my first article and I would really want people to post some
constructive feedback and comments. Let me know how you feel about
this article.

Ketan Patel