How to validate an input field if value is not null in Laravel
Stefan Izdrail
Founder & Senior Architect · 2026-06-29
Title: Efficiently Validating Input Fields: Handling Null Values in Laravel
Introduction
In the world of web development, one crucial aspect that we cannot overlook is data validation. Laravel gives us the flexibility to implement robust validation rules for our forms and API requests. However, handling null values becomes tricky sometimes, especially when you need to ensure a certain field is not empty or its value is not set to null but still needs to be checked against particular validation rules. In this blog post, we will discuss an efficient approach to address this scenario in Laravel 5.4 and beyond.
Validation Rules for Creation and Updating Users
In your Laravel application, you have a User model. You are creating and updating user accounts, and you have defined the following validation rules for their different fields:
1. Name: required if not empty, maximum length of 255 characters
2. Email: required, valid email format, unique within users table, only consider when updating user (otherwise, use a separate validation rule for signup)
3. Password: required and must follow specific password rules like minimum character count, confirmation upon entering
The following is the code for validation in your User model's update method:
```php
public function update(Request $request, $id) {
// Update user details
$this->validate($request, [
'name' => 'required|max:255',
'email' => 'required|email|max:255|unique:users,email,'.$id,
'password' => 'sometimes|min:6|confirmed', // This doesn't work as expected for now. Let's figure it out!
]);
$user = User::find($id);
if ($request->has('name')) {
$user->name = $request->input('name');
}
if ($request->has('email')) {
$user->email = $request->input('email');
}
if ($request->has('password')) {
$user->password = Hash::make(bcrypt($request->input('password'))); // Hash and store the new password
}
// Update the user record
$user->save();
}
```
Problem with Password Validation Using 'sometimes' Rule
As you can observe in the above code, you tried to implement your desired validation using the `sometimes` rule, but it doesn't seem to work as expected. When a user updates their password fields without entering any values or leaving them blank, the password field should still follow specific validation rules - min:6 and confirmed. This is where we might be lacking in our implementation strategy.
A Proper Approach for Validating Password Input Fields
To achieve this desired behavior, you can modify your validator using the Laravel Conditional Rules feature. You'll create a custom validation rule that checks whether the password field is not null and then applies the specific rules accordingly:
1. Create a new class called 'ConfirmedPasswordIfNotNull' in your application.
2. Define the `__construct()` function to pass parameters such as validation rules for non-null values and the default validation rule that will apply if the password is null.
3. Add the custom conditional validation rule using the Laravel Conditional Rules feature.
4. Replace the code for validating the password in your User model's update method with your new custom rule class.
Here's an example implementation:
```php
class ConfirmedPasswordIfNotNull extends Rule {
protected $min, $confirmation;
public function __construct($min = 6, $confirmation = 'confirmed') {
$this->min = $min;
$this->confirmation = $confirmation;
}
public function passes($attribute, $value) {
return !is_null($value) && Validator::make(['password' => $value], [
'password' => array_merge((array)$this->min, (array)$this->confirmation),
])->passes();
}
}
public function update(Request $request, $id) {
// Update user details
$validator = Validator::make($request->all(), [
'name' => 'required|max:255',
'email' => 'required|email|max:255|unique:users,email,'.$id,
'password' => new ConfirmedPasswordIfNotNull(6), // Use custom rule with min:6 and confirmed validation rules if password is not null
]);
// Check for validation errors
if ($validator->fails()) {
$errors = $validator->errors()->all();
// Return a JSON response or redirect as per your application's requirements.
} else {
// Update the user record
$user = User::find($id);
if ($request->has('name')) {
$user->name = $request->input('name');
}
if ($request->has('email')) {
$user->email = $request->input('email');
}
if ($request->has('password')) {
$user->password = Hash::make(bcrypt($request->input('password'))); // Hash and store the new password
}
$user->save();
}
}
```
Conclusion
In this blog post, we have discussed a practical solution to handle input fields where validation rules need to be applied if the value is not null. We introduced the Laravel Conditional Rules feature and implemented a custom rule class 'ConfirmedPasswordIfNotNull' for validating password fields in your User model update method. This approach ensures that your application follows best practices, ensuring efficient data handling without compromising on security or usability.