Welcome to The Cookbook

This method loads the models required by the controller. This loading process is done by CakePHP normally, but this method is handy to have when accessing controllers from a different perspective. If you need CakePHP in a command-line script or some other outside use, constructClasses() may come in handy.

Returns the referring URL for the current request.

Used to tell the user’s browser not to cache the results of the current request. This is different than view caching, covered in a later chapter.

postConditions(array $data, mixed $op, string $bool, boolean $exclusive)

1. postConditions(array $data, mixed $op, string $bool, boolean $exclusive)

Use this method to turn a set of POSTed model data (from HtmlHelper-compatible inputs) into set of find conditions for a model. This function offers a quick shortcut on building search logic. For example, an administrative user may want to be able to search orders in order to know which items need to be shipped. You can use CakePHP’s Form- and HtmlHelpers to create a quick form based on the Order model. Then a controller action can use the data posted from that form to craft find conditions:

function index() {
    $o = $this->Orders->findAll($this->postConditions($this->data));
    $this->set('orders', $o);
}

1. function index() {
2. $o = $this->Orders->findAll($this->postConditions($this->data));
3. $this->set('orders', $o);
4. }

If $this->data[‘Order’][‘destination’] equals “Old Towne Bakery”, postConditions converts that condition to an array compatible for use in a Model->findAll() method. In this case, array(“Order.destination” => “Old Towne Bakery”).

If you want use a different SQL operator between terms, supply them using the second parameter.

/*
Contents of $this->data
array(
    'Order' => array(
        'num_items' => '4',
        'referrer' => 'Ye Olde'
    )
)
*/

//Let’s get orders that have at least 4 items and contain ‘Ye Olde’
$o = $this->Order->findAll($this->postConditions(
    $this->data,
    array('>=', 'LIKE')
));

1. /*
2. Contents of $this->data
3. array(
4. 'Order' => array(
5. 'num_items' => '4',
6. 'referrer' => 'Ye Olde'
7. )
8. )
9. */
10. //Let’s get orders that have at least 4 items and contain ‘Ye Olde’
11. $o = $this->Order->findAll($this->postConditions(
12. $this->data,
13. array('>=', 'LIKE')
14. ));

The key in specifying the operators is the order of the columns in the $this->data array. Since num_items is first, the >= operator applies to it.

The third parameter allows you to tell CakePHP what SQL boolean operator to use between the find conditions. String like ‘AND’, ‘OR’ and ‘XOR’ are all valid values.

Finally, if the last parameter is set to true, and the $op parameter is an array, fields not included in $op will not be included in the returned conditions.

This method is used for paginating results fetched by your models. You can specify page sizes, model find conditions and more. See the pagination section for more details on how to use paginate.

requestAction(string $url, array $options)

This function calls a controller's action from any location and returns data from the action. The $url passed is a CakePHP-relative URL (/controllername/actionname/params). To pass extra data to the receiving controller action add to the $options array.

You can use requestAction() to retrieve a fully rendered view by passing 'return' in the options: requestAction($url, array('return'));

If used without caching requestAction can lead to poor performance. It is rarely appropriate to use in a controller or model.

requestAction is best used in conjunction with (cached) elements – as a way to fetch data for an element before rendering. Let's use the example of putting a "latest comments" element in the layout. First we need to create a controller function that will return the data.

// controllers/comments_controller.php
class CommentsController extends AppController {
    function latest() {
        return $this->Comment->find('all', array('order' => 'Comment.created DESC', 'limit' => 10));
    }
}

1. // controllers/comments_controller.php
2. class CommentsController extends AppController {
3. function latest() {
4. return $this->Comment->find('all', array('order' => 'Comment.created DESC', 'limit' => 10));
5. }
6. }

If we now create a simple element to call that function:

// views/elements/latest_comments.ctp

$comments = $this->requestAction('/comments/latest');
foreach($comments as $comment) {
    echo $comment['Comment']['title'];
}

1. // views/elements/latest_comments.ctp
2. $comments = $this->requestAction('/comments/latest');
3. foreach($comments as $comment) {
4. echo $comment['Comment']['title'];
5. }

We can then place that element anywhere at all to get the output using:

echo $this->element('latest_comments');

1. echo $this->element('latest_comments');

Written in this way, whenever the element is rendered, a request will be made to the controller to get the data, the data will be processed, and returned. However in accordance with the warning above it's best to make use of element caching to prevent needless processing. By modifying the call to element to look like this:

echo $this->element('latest_comments', array('cache'=>'+1 hour'));

1. echo $this->element('latest_comments', array('cache'=>'+1 hour'));

The requestAction call will not be made while the cached element view file exists and is valid.