Form request classes in Laravel - Mini Project: Build & Apply

Form Request Classes in Laravel

📖 Scenario: You are building a simple Laravel application where users can submit their contact information through a form. To keep your controller clean and validate the data properly, you will use Laravel's Form Request classes.

🎯 Goal: Create a Form Request class to validate user input for a contact form. The form should require a name (string, required), email (valid email, required), and message (string, required, minimum 10 characters).

📋 What You'll Learn

Create a Form Request class named ContactFormRequest

Add validation rules for name, email, and message

Authorize all users to make the request

Use the Form Request class in a controller method

💡 Why This Matters

🌍 Real World

Form Request classes help keep your Laravel controllers clean and your validation logic organized. This is common in real Laravel applications handling user input.

💼 Career

Understanding Form Request classes is essential for Laravel developers to write maintainable and secure web applications.

1

Create the Form Request class

Create a Form Request class named ContactFormRequest by running the artisan command php artisan make:request ContactFormRequest. Then, open the generated file and set the authorize method to return true.

Laravel

// Run the artisan command to create ContactFormRequest
// Then open app/Http/Requests/ContactFormRequest.php and set authorize() to return true

// Your code here

Hint

Use the artisan command to generate the class. Then edit the authorize method to allow all users.

2

Add validation rules

In the ContactFormRequest class, add validation rules inside the rules method for name as required string, email as required and valid email, and message as required string with minimum 10 characters.

Laravel

<?php

namespace App\Http\Requests;

use Illuminate\Foundation\Http\FormRequest;

class ContactFormRequest extends FormRequest
{
    public function authorize()
    {
        return true;
    }

    public function rules()
    {
        // Add validation rules here
        return [];
    }
}

Hint

Use Laravel validation rule strings inside the rules method's returned array.

3

Use the Form Request in a controller

In a controller named ContactController, create a method submit that accepts a parameter of type ContactFormRequest. Inside the method, assign the validated data to a variable called $validated by calling $request->validated().

Laravel

validated();
        // Your code here
    }
}

Hint

Type hint the ContactFormRequest in the controller method and call validated() on the request.

4

Complete the controller method

In the submit method of ContactController, add a return statement that returns a JSON response with the validated data under the key data using response()->json().

Laravel

validated();
        // Return JSON response with validated data
    }
}

Hint

Use Laravel's response()->json() helper to return the validated data as JSON.

Practice

1. What is the main purpose of a Form Request class in Laravel?

easy

A. To define routes for the application

B. To create database migrations automatically

C. To manage user authentication sessions

D. To organize and handle validation rules separately from controllers

Solution

1. Step 1: Understand the role of Form Request classes

   Form Request classes are designed to keep validation rules and authorization logic separate from controller code.

2. Step 2: Identify the main benefit

   This separation helps keep controllers clean and improves code organization and security.

3. Final Answer:

   To organize and handle validation rules separately from controllers -> Option D

4. Quick Check:

   Form Request = Validation organization [OK]

Hint: Form Requests separate validation from controllers [OK]

Common Mistakes:

• Confusing Form Requests with database migrations
• Thinking Form Requests handle authentication
• Assuming Form Requests define routes

2. Which of the following is the correct way to create a Form Request class using Artisan CLI?

easy

A. php artisan create:request UserRequest

B. php artisan make:formrequest UserRequest

C. php artisan make:request UserRequest

D. php artisan generate:form UserRequest

Solution

1. Step 1: Recall the Artisan command for Form Requests

   The correct Artisan command to create a Form Request class is make:request.

2. Step 2: Match the command with the options

   php artisan make:request UserRequest uses php artisan make:request UserRequest, which is the correct syntax.

3. Final Answer:

   php artisan make:request UserRequest -> Option C

4. Quick Check:

   Artisan command for Form Request = make:request [OK]

Hint: Use 'make:request' to create Form Requests [OK]

Common Mistakes:

• Using 'make:formrequest' instead of 'make:request'
• Using 'create:request' which is invalid
• Using 'generate:form' which does not exist

3. Given this Form Request class snippet, what will $request->validated() return if the input is ['name' => 'John', 'age' => 20]?

class UserRequest extends FormRequest {
    public function rules() {
        return [
            'name' => 'required|string',
            'age' => 'required|integer|min:18'
        ];
    }
}

medium

A. {'name' => 'John', 'age' => 20}

B. {'name' => 'John'}

C. ValidationException error

D. Empty array []

Solution

1. Step 1: Check validation rules against input

   The rules require 'name' as a string and 'age' as an integer >= 18. Input has 'name' = 'John' (string) and 'age' = 20 (integer, >=18), so validation passes.

2. Step 2: Understand what validated() returns

   The validated() method returns all input fields that passed validation, so it returns the full input array.

3. Final Answer:

   {'name' => 'John', 'age' => 20} -> Option A

4. Quick Check:

   Valid input returns full validated data [OK]

Hint: Validated returns all fields passing rules [OK]

Common Mistakes:

• Assuming partial data is returned
• Expecting an error when input is valid
• Confusing validated() with all() method

4. Identify the error in this Form Request class that causes validation to always pass even with invalid input:

class ProductRequest extends FormRequest {
    public function rules() {
        return [
            'price' => 'required|numeric|min:0'
        ];
    }

    public function authorize() {
        return false;
    }
}

medium

A. The authorize method returns false, blocking validation

B. The rules method is missing required fields

C. The min:0 rule is invalid for numeric fields

D. The class name should be ProductFormRequest

Solution

1. Step 1: Understand the authorize() method role

   The authorize() method controls if the request is allowed. Returning false denies the request before validation.

2. Step 2: Effect of returning false in authorize()

   When authorize() returns false, Laravel automatically denies the request, so validation rules are not applied and the request fails authorization.

3. Final Answer:

   The authorize method returns false, blocking validation -> Option A

4. Quick Check:

   authorize() false blocks request [OK]

Hint: authorize() must return true to run validation [OK]

Common Mistakes:

• Ignoring authorize() method effect
• Thinking min:0 is invalid for numeric
• Believing class name affects validation

5. You want to create a Form Request that validates an optional email field but only if it is present, and it must be a valid email format. Which rule should you use in the rules() method?

hard

A. 'email' => 'nullable|email'

B. 'email' => 'sometimes|email'

C. 'email' => 'required|email'

D. 'email' => 'present|email'

Solution

1. Step 1: Understand optional validation rules

   To validate a field only if it is present in the input, Laravel uses the sometimes rule.

2. Step 2: Compare rules for optional email

   nullable allows null values and skips subsequent rules if null; present requires the field to exist even if empty; sometimes applies validation only if the field is sent.

3. Final Answer:

   'email' => 'sometimes|email' -> Option B

4. Quick Check:

   Use sometimes for optional fields [OK]

Hint: Use sometimes to validate only if field exists [OK]

Common Mistakes:

• Using required which forces presence
• Using nullable which requires field present but can be null
• Using present which requires field always present