JWT Wrapper

Create and validate JWT tokens in a few lines, with the same API for a shared secret or a key pair, and no weak keys accepted.

Why

Signing a token is easy; getting the details right is not. Claims like iat, exp and nbf have to be set and checked, the token has to be read from the Authorization header, and a short HMAC secret silently makes every token easy to forge.

JWT Wrapper takes care of them:

$jwt = new JwtWrapper('example.com', new JwtHashHmacSecret(getenv('JWT_SECRET')));

$token = $jwt->generateToken($jwt->createJwtData(['userId' => 123], 3600));
$data  = $jwt->extractData();   // reads "Authorization: Bearer ..." and validates it

• One API, two kinds of keys. Swap JwtHashHmacSecret for JwtOpenSSLKey (RSA or ECDSA) and nothing else changes.
• No weak secrets. An HMAC secret shorter than the algorithm needs is refused, and generateSecret() creates a proper one.

Features

• Simple API: Create and validate JWT tokens with minimal code
• Flexible Signing: Support for both HMAC (shared secret) and RSA/ECDSA (public/private key) methods
• Automatic Claims: Built-in handling of standard JWT claims (iat, exp, nbf)
• HTTP Integration: Helper methods for extracting tokens from HTTP headers
• Key Management: Intuitive interfaces for different key types

Installation

composer require "byjg/jwt-wrapper"

Quick Example

The HMAC secret must be base64 encoded and decode to at least 64 bytes for the default HS512 algorithm (32 for HS256, 48 for HS384); a shorter key fails with Provided key is too short. See Key Types.

// Create a JWT token using HMAC
$server = "example.com";
// Base64 of at least 64 random bytes, created once with JwtWrapper::generateSecret(64)
$secret = new \ByJG\JwtWrapper\JwtHashHmacSecret(getenv("JWT_SECRET"));
$jwtWrapper = new \ByJG\JwtWrapper\JwtWrapper($server, $secret);

// Add custom data and set expiration
$token = $jwtWrapper->generateToken(
    $jwtWrapper->createJwtData(["userId" => 123], 3600)
);

// Validate and extract data
try {
    $jwtData = $jwtWrapper->extractData($token);
    $userId = $jwtData->data->userId;
} catch (\UnexpectedValueException | \ByJG\JwtWrapper\JwtWrapperException $e) {
    // Handle invalid, expired or tampered token
}

Documentation

Detailed documentation:

Document	Description
Overview	Introduction and core concepts
Key Types	HMAC and OpenSSL key configuration
Creating Tokens	Token generation and customization
Validating Tokens	Token validation and data extraction
API Reference	Complete class and method documentation

Examples

The library includes complete examples in the example directory showing:

• Token creation with login.php
• Token validation with api.php
• Client-side usage with client.html

Running Tests

vendor/bin/phpunit

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Open source ByJG