A package that helps developer to segregate the validation logic from controller to a separate dedicated class. Lumen doesn't have any FormRequest class like Laravel. This will let you do that.

1. Install the package by running composer require anik/form-request from your terminal being in the project directory.
2. Register \Anik\Form\FormRequestServiceProvider::class to your bootstrap/app.php as a provider.

// bootstrap/app.php
$app->register(\Anik\Form\FormRequestServiceProvider::class);

• Create a class that extends Anik\Form\FormRequest class.
• You must override rules method of the Anik\Form\FormRequest class. Define your validation rules in it. Must return an array.
• You can define validation messages by overriding messages method. Default is [].
• You can define custom pretty attribute names by overriding attributes method. Default is [].
• You can override authorize method to define the authorization logic if the client is authorized to submit the form. Must return a boolean value. Default is true. When returning false, it'll raise \Illuminate\Auth\Access\AuthorizationException exception.
• If the validation fails, it will throw Illuminate\Validation\ValidationException.
  • By default, it returns response in {"message": "The given data was invalid.", "errors": []} format with status code 422. Handle the exception in app/Exceptions/Handler.php's render method if you want to modify the response.
  • Override the statusCode method to return the status of your choice. Must return int. Default is 422.
  • Override the errorMessage method to return the message of your choice. Must return string. Default is The given data was invalid.
  • Override the errorResponse method to return response of your choice when the validation fails. Must return either of type \Symfony\Component\HttpFoundation\Response or null.
• Now you can inject your Request class through the method injections. All the methods of Laravel\Lumen\Http\Request class is available in your request class.
• The FormRequest::validated() method will return the validated data when the validation passes.