Custom validation rules in Laravel - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a custom validation rule class in Laravel.

Laravel

php artisan make:[1] UniqueEmail

Drag options to blanks, or click blank then click option'

Amake:rule

Bvalidation

Cmake:validation

Drule

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'make:validation' instead of 'make:rule'.

Using just 'rule' without 'make:'.

The correct artisan command to create a custom validation rule is make:rule.

2fill in blank

medium

Complete the method signature to define the validation logic inside the custom rule class.

Laravel

public function [1]($attribute, $value) { }

Drag options to blanks, or click blank then click option'

Acheck

Bvalidate

Cpasses

Dhandle

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'validate' or 'check' instead of 'passes'.

Missing the required parameters in the method.

The method passes is used in Laravel custom rules to define validation logic.

3fill in blank

hard

Fix the error in the validation logic to fail validation when the value is not 'admin'.

Laravel

if ($value !== '[1]') {
    $fail('The :attribute must be admin.');
}

Drag options to blanks, or click blank then click option'

Auser

Badmin

Cguest

Droot

Attempts:

3 left

💡 Hint

Common Mistakes

Using other role names like 'user' or 'guest' which do not match the requirement.

Leaving the string empty or misspelled.

The validation should fail if the value is not 'admin', so the string 'admin' must be used.

4fill in blank

hard

Fill both blanks to register the custom rule in a form request's rules method.

Laravel

public function rules() {
    return [
        'email' => ['required', new [1]()],
        'username' => ['required', '[2]'],
    ];
}

Drag options to blanks, or click blank then click option'

AUniqueEmail

Bstring

Cemail

Dunique

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'email' or 'unique' as the custom rule class name.

Using the custom rule class name as a string rule.

The custom rule class is UniqueEmail, and 'string' is a standard Laravel validation rule.

5fill in blank

hard

Fill all three blanks to create a custom validation rule that checks if a number is even.

Laravel

public function passes($attribute, $value) {
    return $value [1] 2 [2] 0;
}

public function message() {
    return '[3]';
}

Drag options to blanks, or click blank then click option'

A%

B===

CThe :attribute must be an even number.

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using '===' which is strict equality and may cause issues with type.

Incorrect message text or missing message method.

The modulo operator '%' checks remainder, '==' compares equality, and the message explains the validation rule.

Practice

1. What is the main purpose of creating a custom validation rule in Laravel?

easy

A. To define your own logic for validating data beyond built-in rules

B. To change the database schema automatically

C. To create new database tables

D. To generate HTML forms automatically

Solution

1. Step 1: Understand Laravel validation rules

   Laravel provides built-in rules but sometimes you need to check data in a way not covered by them.

2. Step 2: Purpose of custom validation rules

   Custom rules let you write your own logic to validate data exactly as you want.

3. Final Answer:

   To define your own logic for validating data beyond built-in rules -> Option A

4. Quick Check:

   Custom validation = custom logic [OK]

Hint: Custom rules check data your way, not Laravel's default [OK]

Common Mistakes:

• Thinking custom rules change database structure
• Confusing validation with form generation
• Assuming custom rules create tables

2. Which method must you implement in a Laravel custom validation rule class to check if the data passes validation?

easy

A. check

B. message

C. validate

D. passes

Solution

1. Step 1: Recall custom rule methods

   Laravel custom validation rules require two methods: passes and message.

2. Step 2: Identify method for validation logic

   The passes method contains the logic to decide if the data is valid or not.

3. Final Answer:

   passes -> Option D

4. Quick Check:

   passes() checks data validity [OK]

Hint: passes() returns true/false for validation [OK]

Common Mistakes:

• Using message() to check data validity
• Assuming validate() or check() are required methods
• Confusing method names

3. Given this custom rule class snippet, what will $rule->passes('age', 17) return?

class AdultRule implements \Illuminate\Contracts\Validation\Rule {
    public function passes($attribute, $value) {
        return $value >= 18;
    }
    public function message() {
        return 'You must be an adult.';
    }
}

medium

A. true

B. Throws an error

C. false

D. null

Solution

1. Step 1: Understand the passes method logic

   The method returns true if the value is 18 or more, false otherwise.

2. Step 2: Evaluate passes with value 17

   Since 17 is less than 18, the method returns false.

3. Final Answer:

   false -> Option C

4. Quick Check:

   17 < 18 means passes() = false [OK]

Hint: Check condition in passes() with given value [OK]

Common Mistakes:

• Assuming 17 passes as adult
• Thinking passes() throws error for numbers
• Confusing message() with passes()

4. What is wrong with this custom validation rule class?

class EvenNumberRule implements \Illuminate\Contracts\Validation\Rule {
    public function passes($attribute, $value) {
        return $value % 2 == 0
    }
    public function message() {
        return 'The number must be even.';
    }
}

medium

A. message method should return a boolean

B. Missing semicolon after return statement in passes method

C. passes method should accept only one parameter

D. Class must extend a base validation class

Solution

1. Step 1: Check syntax in passes method

   The return statement lacks a semicolon at the end, causing a syntax error.

2. Step 2: Verify other method signatures

   message() correctly returns a string, passes() correctly has two parameters, and implementing the interface is enough.

3. Final Answer:

   Missing semicolon after return statement in passes method -> Option B

4. Quick Check:

   Missing semicolon = syntax error [OK]

Hint: Look for missing semicolons in PHP code [OK]

Common Mistakes:

• Thinking message() must return boolean
• Assuming passes() takes one parameter
• Believing class must extend base class

5. You want to create a custom validation rule that checks if a string contains only vowels. Which approach correctly implements the passes method?

hard

A. return preg_match('/^[aeiouAEIOU]+$/', $value) === 1;

B. return strlen($value) > 0 && ctype_alpha($value);

C. return strpos($value, 'aeiou') !== false;

D. return $value == strtolower($value);

Solution

1. Step 1: Understand the requirement

   The string must contain only vowels (a, e, i, o, u) in any case.

2. Step 2: Analyze each option

   return preg_match('/^[aeiouAEIOU]+$/', $value) === 1; uses regex to check if the string contains only vowels from start to end. return strlen($value) > 0 && ctype_alpha($value); checks only letters but not vowels. return strpos($value, 'aeiou') !== false; checks if 'aeiou' substring exists, which is incorrect. return $value == strtolower($value); checks if string is lowercase, unrelated to vowels.

3. Final Answer:

   return preg_match('/^[aeiouAEIOU]+$/', $value) === 1; -> Option A

4. Quick Check:

   Regex matching only vowels = correct passes() [OK]

Hint: Use regex to match only vowels in string [OK]

Common Mistakes:

• Using ctype_alpha without vowel check
• Checking substring instead of full string
• Confusing case check with vowel check