CakePHP - Adding Form Validation based on Database Fields - regex

Question

I need to validate shipping information entered when goods are dispatched. (I am having a nightmare using Cake!)
Each shipping company has a different format for their tracking references. I have written some regex to validate, and these are stored in my database.
All the validation for CakePHP happens in the model so I cannot use $this to retrieve the correct regex.
The regex is available in the view; is there anyway to use this to validate before the form is submitted?
I am currently sending the data through an ajax call
Controller
public function editTracking() {
$this->autoRender = false;
if ($this->request->is('ajax')) {
if($this->GoodsOutNote->save($this->request->data['GoodsOutNote'])){
$this->GoodsOutNote->save($this->request->data['GoodsOutNote']);
print_r($this->request->data['GoodsOutNote']['tracking_details']);
}else{
print_r($errors = $this->GoodsOutNote->validationErrors);
}
}
}
View
<?php echo $this->Form->create('GoodsOutNote',array(
'action'=>'editTracking','default' => false)); ?>
<fieldset>
<?php
echo $this->Form->input('id',array(
'default'=>$goodsOutNote['GoodsOutNote']['id']));
echo $this->Form->input('tracking_details',array(
'default'=>$goodsOutNote['GoodsOutNote']['tracking_details']));
?>
</fieldset>
<?php echo $this->Form->end(__('Submit'));
$data = $this->Js->get('#GoodsOutNoteEditTrackingForm')->serializeForm(array(
'isForm' => true, 'inline' => true));
$this->Js->get('#GoodsOutNoteEditTrackingForm')->event('submit',
$this->Js->request(
array('action' => 'editTracking', 'controller' => 'goods_out_notes'),
array(
'update' => '#tracking_details,#GoodsOutNoteTrackingDetails',
'data' => $data,
'async' => true,
'dataExpression'=>true,
'method' => 'PUT'
)
)
);
echo $this->Js->writeBuffer();
?>
In the view, I can use $goodsOutNote['ShippingMethod']['valid_regex'] to access the correct format but I am lost as to how I can pass this to the form.

Answer 1

I have fixed this using the following approach.
In my controller, I retrieve the full record that I am about to edit. I can then validate the input using preg_match(). I would really appreciate any comments on this - is there a better approach?
public function editTracking() {
$this->autoRender = false;
if ($this->request->is('ajax')) {
$id = $this->request->data['GoodsOutNote']['id'];
$options = array('conditions' => array('GoodsOutNote.' . $this->GoodsOutNote->primaryKey => $id));
$goodsOutNote = $this->GoodsOutNote->find('first', $options);
$trackingRef = $this->request->data['GoodsOutNote']['tracking_details'];
$regex = "/".$goodsOutNote['ShippingMethod']['valid_regex']."/";
if(preg_match($trackingRef,$regex)){
if($this->GoodsOutNote->save($this->request->data['GoodsOutNote'])){
$this->GoodsOutNote->save($this->request->data['GoodsOutNote']);
print_r($trackingRef);
}
else{
print_r($errors = $this->GoodsOutNote->validationErrors);
}
}
else {
print_r($errors = $trackingRef.'is not valid');
}
}
}