Laravel Validation

Form requests as single source of truth for validation, with comprehensive testing patterns.

Core Concepts

form-requests.md - Validation rules:

• Array-based validation rules
• Custom validation rules
• Conditional validation
• Custom error messages
• DTO transformation via toDto()

validation-testing.md - Validation testing:

• RequestDataProviderItem helper
• Pest datasets for systematic testing
• Built-in helper methods (string, email, number, date, array, boolean)
• Nested array testing
• Conditional validation testing
• Real-world examples

Pattern

final class CreateOrderRequest extends FormRequest
{
    public function rules(): array
    {
        return [
            'user_id' => ['required', 'integer', 'exists:users,id'],
            'items' => ['required', 'array', 'min:1'],
            'items.*.product_id' => ['required', 'integer'],
            'items.*.quantity' => ['required', 'integer', 'min:1'],
        ];
    }

    public function toDto(): CreateOrderDto
    {
        return CreateOrderDto::from($this->validated());
    }
}

All validation lives in form requests. Test validation systematically.