How to get a single validation rule from model in CodeIgniter 4?

Created:12 Oct 2021 00:05:56 , in  Web development

Here is a little bit on how to get a single validation rule from a model in CodeIgniter 4. Why would you want to do a thing like this? Well, sometimes you want to validate only a single piece of input data, like for example a customer order code.

In Codeigniter 4 validation rules are stored in models.

To get a single rule from a model you would do something like this:

$rule = $orderModel -> getValidationRules(['only' => ['code']])['code'];

Here is how to use this in a broader context:

Supposed, that in your Order model among others you have a validation rule like this:

protected $validationRules = [
    .
    .
    'code' => 'required|min_length[17]|max_length[40]|alpha_numeric',
    .
    .
];

and you want to use it in your controller without duplication.

To validate a code coming into your controller as user input with the rule above you would do something like this:

$code = trim(filter_var($code,FILTER_SANITIZE_STRING));

to sanitize the input string, and then

// if input data is valid:
if($validation -> check($code, $orderModel -> getValidationRules(['only' => ['code']])['code'])){
  // input valid
// if it is not do this:
} else {
  // input invalid
}

to validate it.

getValidationRules is yet another little things that makes CodeIgniter 4 such a cool little PHP framework.

This post was updated on 13 Oct 2021 12:01:05

Tags:  CodeIgniter ,  php