README

Generate date-based keys and validate them within a time window. Uses a secret alphabet for base-N encoding + SHA256 hashing.

PHP port of expiring-key-generator — keys are cross-compatible with the same secret.

• Zero dependencies (besides PHP 8.1+)
• Algorithmic generation
• No database needed

Install

composer require horsev/expiring-key-generator

Usage

<?php

use Horsev\ExpiringKeyGenerator\ExpiringKeyGenerator;

// 1. Generate a secret key (store this securely)
$secretKey = ExpiringKeyGenerator::generateSecretKey();

// 2. Daily keys — generate and validate within N days
$generateKey = ExpiringKeyGenerator::createKeyGenerator($secretKey);
$key = $generateKey(new DateTime());
$isKeyValid = ExpiringKeyGenerator::createKeyValidator($secretKey);
$isKeyValid($key, new DateTime(), 28); // true

// 3. Hourly keys — generate and validate within N hours (1–24)
$generateHourlyKey = ExpiringKeyGenerator::createHourlyKeyGenerator($secretKey);
$hourlyKey = $generateHourlyKey(new DateTime());
$isHourlyKeyValid = ExpiringKeyGenerator::createHourlyKeyValidator($secretKey);
$isHourlyKeyValid($hourlyKey, new DateTime(), 5); // true

API

generateSecretKey(): string

Returns a randomly shuffled 34-character string from a safe alphabet (A-Z without O, 1-9 without 0).

createKeyGenerator(string $secretKey): Closure

Throws if $secretKey is not a valid 34-character permutation of the safe alphabet.

Returns fn(DateTimeInterface $date): string that encodes a date into a deterministic base64 SHA256 hash.

createKeyValidator(string $secretKey): Closure

Throws if $secretKey is invalid.

Returns fn(string $hash, DateTimeInterface $currentDate, int $days): bool that checks whether a key was generated within the last $days days.

createHourlyKeyGenerator(string $secretKey): Closure

Returns fn(DateTimeInterface $date): string that encodes date+hour into a hash. Uses YYYYMMDDHH (10 digits).

createHourlyKeyValidator(string $secretKey): Closure

Returns fn(string $hash, DateTimeInterface $currentDate, int $hours): bool for 1–24 hour windows.

License

MIT