README

Simple and fluent input validation library for PHP 8.2+.

Features

• Fluent API: Chain validation rules together for readable, expressive code
• Required & Optional Fields: Distinguish between required and optional fields
• Nested Field Access: Use dot notation to validate nested array structures
• Comprehensive Rules: Built-in validators for common use cases
• Custom Validation: Support for custom callback functions
• Type Safety: Full PHP 8.2+ type declarations and strict types

Installation

Install via Composer:

composer require vaibhavpandeyvpz/filtr

Quick Start

<?php

use Filtr\Validator;

$validator = new Validator();
$validator->required('email')->isNotBlank()->isEmailAddress();
$validator->required('password')->isNotBlank()->isHavingLength(8, 32);
$validator->key('remember_me')->isBoolean();

$result = $validator->validate([
    'email' => 'user@example.com',
    'password' => 'securepassword123',
    'remember_me' => true,
]);

if ($result->valid()) {
    // Validation passed
    echo "All fields are valid!";
} else {
    // Display errors
    foreach ($result->errors() as $field => $message) {
        echo "$field: $message\n";
    }
}

Basic Usage

Required Fields

Fields marked as required() must be present in the data, otherwise validation fails:

$validator = new Validator();
$validator->required('username')->isNotBlank();

$result = $validator->validate(['username' => 'john_doe']); // ✓ Valid
$result = $validator->validate([]); // ✗ Invalid: "username: This value is required."

Optional Fields

Fields marked as key() are only validated if they are present in the data:

$validator = new Validator();
$validator->key('bio')->isString();

$result = $validator->validate(['bio' => 'Software developer']); // ✓ Valid
$result = $validator->validate([]); // ✓ Valid (field not present, so not validated)

Chaining Rules

You can chain multiple validation rules together. All rules must pass for validation to succeed:

$validator = new Validator();
$validator->required('email')
    ->isNotBlank()
    ->isEmailAddress()
    ->isHavingLength(5, 255);

$result = $validator->validate(['email' => 'user@example.com']); // ✓ Valid

Nested Fields

Use dot notation to validate nested array structures:

$validator = new Validator();
$validator->required('user.name')->isNotBlank();
$validator->required('user.email')->isEmailAddress();
$validator->key('user.address.city')->isString();

$result = $validator->validate([
    'user' => [
        'name' => 'John Doe',
        'email' => 'john@example.com',
        'address' => [
            'city' => 'New York'
        ]
    ]
]); // ✓ Valid

Available Validation Rules

Type Validation

• isBoolean() - Validates that the value is a boolean
• isInteger() - Validates that the value is an integer
• isString() - Validates that the value is a string
• isNumber() - Validates that the value is numeric
• isOfType(string $type) - Validates that the value is of a specific type

$validator->key('age')->isInteger();
$validator->key('active')->isBoolean();
$validator->key('score')->isNumber();

String Validation

• isNotBlank() - Validates that the value is not empty
• isBlank() - Validates that the value is blank
• isHavingLength(int $min, ?int $max = null) - Validates string length
• isMatchingWith(string $regexp) - Validates against a regular expression

$validator->required('password')
    ->isNotBlank()
    ->isHavingLength(8, 32);

$validator->key('phone')->isMatchingWith('~^\+?[1-9]\d{1,14}$~');

Email & URL Validation

• isEmailAddress() - Validates email addresses
• isUrl() - Validates URLs

$validator->required('email')->isEmailAddress();
$validator->key('website')->isUrl();

IP Address Validation

• isIpAddress(int $flags = 0) - Validates IP addresses
• isIpv4Address() - Validates IPv4 addresses
• isIpv6Address() - Validates IPv6 addresses

$validator->key('ip')->isIpAddress();
$validator->key('ipv4')->isIpv4Address();
$validator->key('ipv6')->isIpv6Address();

Date & Time Validation

• isDateTime(?string $format = null) - Validates date/time strings

$validator->key('birthday')->isDateTime('Y-m-d');
$validator->key('created_at')->isDateTime('Y-m-d H:i:s');

Credit Card Validation

• isCreditCard(string|array|CreditCardType|null $types = null) - Validates credit card numbers

use Filtr\Rule\CreditCardType;

$validator->required('card_number')->isCreditCard();
$validator->required('card_number')->isCreditCard(CreditCardType::Visa);
$validator->required('card_number')->isCreditCard([CreditCardType::Visa, CreditCardType::Mastercard]);

Comparison Validation

• isEqualTo(mixed $value) - Loose equality (==)
• isNotEqualTo(mixed $value) - Loose inequality (!=)
• isSameAs(mixed $value) - Strict equality (===)
• isNotSameAs(mixed $value) - Strict inequality (!==)
• isOneOf(array $values) - Value must be in the given array
• isTrue() - Value must be true
• isFalse() - Value must be false

$validator->key('status')->isOneOf(['active', 'inactive', 'pending']);
$validator->key('confirmed')->isTrue();
$validator->key('deleted')->isFalse();

Numeric Validation

• isInRange(int $min, int $max) - Validates numeric range

$validator->key('age')->isInRange(18, 120);
$validator->key('score')->isInRange(0, 100);

Count Validation

• isHavingCount(int $number) - Validates that countable values have exact count

$validator->key('tags')->isHavingCount(3);
$validator->key('items')->isHavingCount(5);

Custom Validation

• is(callable $callback) - Custom validation using a callback function

$validator->key('username')->is(function($value) {
    return preg_match('/^[a-z0-9_]+$/', $value) === 1;
});

// Or using arrow functions (PHP 7.4+)
$validator->key('even_number')->is(fn($value) => is_numeric($value) && $value % 2 === 0);

Special Validators

• isMacAddress() - Validates MAC addresses

$validator->key('mac')->isMacAddress();

Working with Results

The validate() method returns a ResultInterface instance:

$result = $validator->validate($data);

// Check if validation passed
if ($result->valid()) {
    // All validations passed
}

// Get all errors
$errors = $result->errors();
// Returns: ['field_name' => 'error message', ...]

// Check for specific field errors
if (isset($errors['email'])) {
    echo $errors['email'];
}

Error Messages

Each validation rule provides a default error message. You can customize the message for required fields:

$validator->required('email', 'Please provide a valid email address')
    ->isEmailAddress();

Examples

User Registration Form

$validator = new Validator();

// Required fields
$validator->required('username')
    ->isNotBlank()
    ->isString()
    ->isHavingLength(3, 20)
    ->isMatchingWith('~^[a-zA-Z0-9_]+$~');

$validator->required('email')
    ->isNotBlank()
    ->isEmailAddress();

$validator->required('password')
    ->isNotBlank()
    ->isHavingLength(8, 128);

$validator->required('age')
    ->isInteger()
    ->isInRange(18, 120);

// Optional fields
$validator->key('bio')->isString()->isHavingLength(0, 500);
$validator->key('website')->isUrl();
$validator->key('newsletter')->isBoolean();

$result = $validator->validate($_POST);

API Request Validation

$validator = new Validator();

$validator->required('api_key')->isNotBlank();
$validator->required('action')->isOneOf(['create', 'update', 'delete']);
$validator->required('data')->isOfType('array');

// Nested validation
$validator->required('data.id')->isInteger();
$validator->required('data.name')->isNotBlank();
$validator->key('data.metadata')->isOfType('array');

$result = $validator->validate($requestData);

Requirements

• PHP 8.2 or higher

License

This library is open-sourced software licensed under the MIT license.

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.