Why Custom validation rules in Laravel? - Purpose & Use Cases

The Big Idea

Discover how to make your app smarter by creating your own data rules that work everywhere automatically!

The Scenario

Imagine you have a form where users enter data, and you need to check if the data meets special rules that built-in checks don't cover.

You try to write all these checks manually every time you get input.

The Problem

Manually checking each input everywhere is tiring and easy to forget.

It leads to repeated code, mistakes, and inconsistent checks across your app.

The Solution

Custom validation rules let you write your special checks once and reuse them everywhere.

Laravel runs these rules automatically when validating input, keeping your code clean and reliable.

Before vs After

✗ Before

$input = request()->all();
if(strlen($input['username']) < 5) {
  return 'Username too short';
}

✓ After

$request->validate([
  'username' => ['required', new CustomUsernameRule()]
]);

What It Enables

You can easily enforce any unique or complex data rules consistently across your whole application.

Real Life Example

For example, checking if a username contains only allowed characters or if a coupon code is valid before accepting it.

Key Takeaways

Manual checks are repetitive and error-prone.

Custom validation rules centralize and reuse your special checks.

This keeps your app reliable and your code clean.