Koldy PHP Framework — Validation

Koldy\Validator is a rule-based data validation engine. It validates arrays of data against string-based rules, similar to Laravel's validator.

Basic Usage

use Koldy\Validator;

// Validate request parameters automatically
$validator = Validator::create([
    'email' => 'required|email',
    'password' => 'required|minLength:8',
    'name' => 'required|alpha|maxLength:100'
]);
// Throws Validator\Exception if validation fails

// Access validated data
$data = $validator->getValid();          // array
$data = $validator->getValidObject();    // stdClass
$email = $validator->getValid('email');  // single field

Manual Validation

// Validate custom data (not from request)
$validator = new Validator([
    'age' => 'required|integer|min:0|max:150',
    'email' => 'required|email'
], [
    'age' => '25',
    'email' => 'user@example.com'
]);

if ($validator->validate()) {
    $data = $validator->getValid();
} else {
    $errors = $validator->getInvalid();  // field => error message
}

Strict Mode

Only allow fields defined in rules — extra fields cause validation failure:

$validator = new Validator([
    'email' => 'required|email',
    'password' => 'required'
]);
$validator->setOnly(true);  // reject any parameters not in rules
$validator->validate();

Checking Results

$validator->isAllValid();          // bool — all fields valid
$validator->isValid('email');      // bool — specific field valid
$validator->getValid();            // all valid data as array
$validator->getValid('email');     // single valid value
$validator->getInvalid();          // all invalid fields with messages
$validator->getInvalid('email');   // error message for specific field

Built-in Validation Rules

Presence Rules

Rule	Description
required	Field must be present and non-empty
present	Field must exist in data (can be empty)

Type Rules

Rule	Description
integer	Must be a valid integer
numeric	Must be a numeric value
decimal:N	Must be a decimal with at most N decimal places
boolean or bool	Must be a boolean-like value (true, false, 1, 0, "1", "0")
alpha	Must contain only alphabetic characters
alphaNum	Must contain only alphanumeric characters
hex	Must be a valid hexadecimal string
email	Must be a valid email address
slug	Must be a valid URL slug (lowercase, dashes, no spaces)
uuid	Must be a valid UUID (8-4-4-4-12 hex format)
date	Must be a valid date string
array or array:N	Must be an array, optionally with exactly N elements

Size Rules

Rule	Description
min:N	Minimum numeric value
max:N	Maximum numeric value
minLength:N	Minimum string length
maxLength:N	Maximum string length
length:N	Exact string length

Comparison Rules

Rule	Description
same:field	Must have the same value as another field
different:field	Must have a different value than another field
is:value	Must equal the exact value
anyOf:val1,val2,...	Must be one of the listed values
startsWith:prefix	Must start with the given prefix
endsWith:suffix	Must end with the given suffix

Database Rules

Rule	Description
unique:Table,column	Must be unique in the database table
exists:Table,column	Must exist in the database table

Security Rules

Rule	Description
csrf	Validates CSRF token

Rule Syntax

Rules are pipe-separated strings. Rules with parameters use colon notation:

'field' => 'required|email'
'field' => 'required|minLength:3|maxLength:100'
'field' => 'required|anyOf:active,inactive,pending'
'field' => 'integer|min:0|max:999'
'field' => 'required|unique:App\\Db\\User,email'
'field' => 'required|decimal:2'
'field' => 'required|same:password_confirmation'

Custom Validation with Closures

You can pass a closure as a rule for custom validation logic:

$validator = new Validator([
    'email' => function (mixed $value, string $field, array $allData): ?string {
        // Return null if valid, or error message string if invalid
        if (!str_ends_with($value, '@company.com')) {
            return 'Email must be a company email address';
        }
        return null;
    }
]);

Factory Method

The create() factory validates immediately and throws on failure:

// This throws Validator\Exception if validation fails
$validator = Validator::create([
    'email' => 'required|email',
    'password' => 'required|minLength:8'
]);

// With custom data
$validator = Validator::create($rules, $customData);

// Without auto-throw
$validator = Validator::create($rules, $data, false);
if (!$validator->isAllValid()) {
    // handle errors
}