Custom Rules

Custom rules work best when you decide first whether the behavior belongs in the browser, on the server, or both.

Client-side custom rules#

Use the global bundle helper or the core RuleRegistry to add a browser-only rule.

LaravelClientValidation.extend('phone', (value) => {
    if (!value) {
        return true;
    }

    return /^\+?[\d\s-]{10,}$/.test(value);
}, 'The :attribute must be a valid phone number.');

You can then reference the rule anywhere you already use package directives.

<input name="phone" @validateBlur('phone', 'required|phone')>

ES module registration#

import { RuleRegistry } from 'laravel-client-validation/core';

RuleRegistry.extend('sku', (value) => /^[A-Z]{3}-\d{4}$/.test(value), 'The :attribute must be a valid SKU.');

Server-side custom rules#

Use the package facade when the rule depends on backend state or you want the parser to treat it as server-side by default.

use MrPunyapal\ClientValidation\Facades\ClientValidation;

ClientValidation::extend('strong_password', function ($attribute, $value) {
    return preg_match('/^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)/', (string) $value) === 1;
}, 'Password must contain uppercase, lowercase, and numbers.');

The package registers that rule with Laravel's validator and classifies it as server-side unless you also provide a matching browser implementation.

Shared rule strategy#

If the same rule should behave consistently in both places, keep the rule name identical and maintain one browser implementation and one Laravel implementation.

$rules = [
    'sku' => 'required|sku',
];

LaravelClientValidation.extend('sku', (value) => /^[A-Z]{3}-\d{4}$/.test(value));

Testing custom rules#

• Validate the JavaScript rule in a browser or JavaScript test.
• Validate the PHP rule with Laravel or package tests.

Documentation checklist for new rules#

• Link to the user-facing rule description from validation rules.
• Show one passing example and one failing example.
• State clearly whether the rule is browser-only, server-only, or shared.
• Avoid renaming an existing rule unless you are prepared to update every internal link and every rule string that references it.