CakePHP Validation depending on other field - cakephp

Question

I wonder if it is possible with CakePHP validation rules to validate a field depending on another.
I have been reading the documentation about custom validation rules but the $check param only contains the value of the current field to validate.
For example. I would like to define the verify_password field as required only if the new_password field is not empty. (in case
I could do it with Javascript anyway but i wonder if it is possible to do it directly with CakePHP.

Answer 1

When you validate data on a model, the data is already set(). This means that you can access it on the model's $data property. The example below checks the field we're validating to make sure it's the same as some other field defined in the validation rules (such as a password confirm field).
The validation rule would look something like this:
var $validate = array(
'password' => array(
'minLength' => array(
'rule' => array('minLength', 6),
'message' => 'Your password must be at least 6 characters long.'
),
'notempty' => array(
'rule' => 'notEmpty',
'message' => 'Please fill in the required field.'
)
),
'confirm_password' => array(
'identical' => array(
'rule' => array('identicalFieldValues', 'password'),
'message' => 'Password confirmation does not match password.'
)
)
);
Our validation function then looks at the passed field's data (confirm_password) and compares it against he one we defined in the rule (passed to $compareFiled).
function identicalFieldValues(&$data, $compareField) {
// $data array is passed using the form field name as the key
// so let's just get the field name to compare
$value = array_values($data);
$comparewithvalue = $value[0];
return ($this->data[$this->name][$compareField] == $comparewithvalue);
}
This is a simple example, but you could do anything you want with $this->data.
The example in your post might look something like this:
function requireNotEmpty(&$data, $shouldNotBeEmpty) {
return !empty($this->data[$this->name][$shouldNotBeEmpty]);
}
And the rule:
var $validate = array(
'verify_password' => array(
'rule' => array('requireNotEmpty', 'password')
)
);