CodeIgniter custom validation library function not working - codeigniter

Question

I've created custom validation library class MY_Form_validation as MY_Form_validation.php in application/libraries as follows.
<?php if (!defined('BASEPATH')) exit('No direct script access allowed');
class MY_Form_validation extends CI_Form_validation {
public function __construct($rules = array()) {
parent::__construct($rules);
}
public function file_required($file) {
if($file['size']===0) {
$this->set_message('file_required', 'Uploading a file for %s is required.');
return false;
}
return true;
}
}
?>
In my validation function I've included following rules as follows.
public function validate() {
$this->load->library('form_validation');
$config = array(
array(
'field' => 'name',
'label' => 'Name',
'rules' => 'trim|required|xss_clean'
),
array(
'field' => 'display_photo',
'label' => 'Display Photo',
'rules' => 'trim|good|file_required|xss_clean'
),
);
$this->form_validation->set_rules($config);
if ($this->form_validation->run()) {
return true;
}
return false;
}
The core validation rules are working fine but custom rule is not working. So please help me to get the soultion and Its literally wasting my time. The work would be more appreciated.

Answer 1

As far as i understand your function always return true. Because of $file Not $_FILES
public function file_required($file) {
if($_FILES[$file]['size']===0) {
$this->set_message('file_required', 'Uploading a file for %s is required.');
return false;
}
return true;
}

Answer 2

Check the rules in the function validate()
What I think it's incorrect:
$config = array(
array(
'field' => 'name',
'label' => 'Name',
'rules' => 'trim|required|xss_clean'
),
array(
'field' => 'display_photo',
'label' => 'Display Photo',
'rules' => 'trim|good|file_required|xss_clean'
),
);
What I think is correct:
$config = array(
array(
'field' => 'name',
'label' => 'Name',
'rules' => 'trim|required|xss_clean'
),
array(
'field' => 'display_photo',
'label' => 'Display Photo',
'rules' => 'trim|file_required|xss_clean'
),
);
I think good is not a php function, or an internal codeigniter function.
Edit:
What about using:
if ($file['size'] == 0) {
Instead of
if ($file['size'] === 0) {
Using === means the value MUST BE integer 0, but if $file['size'] returns 0 as string the if won't be true, and the function always will return true.

Answer 3

I had the same problem and found the cause while looking in CodeIgniter's source code. It seems the writers thought that if a field didn't have "required", then it would just skip all the rules and always return that the form has validated. See it for yourself from their code:
// If the field is blank, but NOT required, no further tests are necessary
if ( ! in_array('required', $rules) AND is_null($postdata))
However, if you add "callback_" in front of your rule, you can still make it run, for the procedure, look here:
https://www.codeigniter.com/userguide2/libraries/form_validation.html#callbacks