php 40 lines · 6 steps

How a custom phone validation rule works in Laravel

A Laravel ValidationRule wraps libphonenumber to parse and validate phone numbers against a default region.

Explained by highlit

Laravel Intermediate validation custom-rules dependency error-handling internationalization

1<?php
2 
3namespace App\Rules;
4 
5use Closure;
6use Illuminate\Contracts\Validation\ValidationRule;
7use libphonenumber\NumberParseException;
8use libphonenumber\PhoneNumberUtil;
9 
10class ValidPhoneNumber implements ValidationRule
11{
12    public function __construct(
13        private readonly ?string $defaultRegion = 'US',
14    ) {
15    }
16 
17    public function validate(string $attribute, mixed $value, Closure $fail): void
18    {
19        if (! is_string($value) || trim($value) === '') {
20            $fail('The :attribute must be a valid phone number.')->translate();
21 
22            return;
23        }
24 
25        $util = PhoneNumberUtil::getInstance();
26 
27        try {
28            $number = $util->parse($value, $this->defaultRegion);
29        } catch (NumberParseException) {
30            $fail('The :attribute is not a recognizable phone number.')->translate();
31 
32            return;
33        }
34 
35        if (! $util->isValidNumber($number)) {
36            $fail('The :attribute is not a valid phone number for the :region region.')
37                ->translate(['region' => $this->defaultRegion]);
38        }
39    }
40}

01 / 01

STEP 01

Walkthrough

Space play ←→ step click any line

Three takeaways

1Implementing ValidationRule lets you encapsulate complex domain checks as a reusable, injectable object.
2Calling $fail and returning early keeps each failure path isolated and prevents downstream code from running on bad input.
3Delegating phone parsing to libphonenumber gives you region-aware correctness instead of fragile regex guesses.

Related explainers

typescript

import { NestFactory } from '@nestjs/core';
import { DocumentBuilder, SwaggerModule } from '@nestjs/swagger';
import { ValidationPipe } from '@nestjs/common';
import { ApiProperty } from '@nestjs/swagger';

Wiring validation and Swagger docs in NestJS

validation openapi decorators

Intermediate 8 steps

php

<?php
 
namespace App\Console\Commands;

Releasing stale document locks in Laravel

artisan-command transactions row-locking

Intermediate 6 steps

ruby

class TemplateInterpolator
  PLACEHOLDER = /\{\{\s*([\w.]+)\s*\}\}/
 
  def initialize(strict: false)

Interpolating templates with dotted keys in Ruby

regex string-interpolation hash-traversal

Intermediate 6 steps

php

<?php
 
namespace App\Providers;

Subdomain multi-tenancy routing in Laravel

multi-tenancy service-container route-binding

Advanced 7 steps

php

<?php
 
namespace App\Broadcasting;

Authorizing presence channels in Laravel

broadcasting authorization presence-channels

Intermediate 3 steps

package config
 
import (
	"fmt"

A thread-safe config singleton in Go

singleton concurrency environment-variables

Intermediate 7 steps

Share this explainer

Here's the card — post it anywhere.

How a custom phone validation rule works in Laravel — share card

Made with highlit — turn any snippet into a walkthrough like this in about a minute.

Explain your code