KotJWT

KotJWT is a lightweight Kotlin Multiplatform library designed for encoding, decoding, and managing JSON Web Tokens (JWT) and refresh tokens. It supports a variety of cryptographic algorithms, including HMAC SHA-256, ECDSA, and RSA, while providing essential features like token expiration validation, blacklist management, and secure token handling.

✨ Features

• JWT Support – Encode and decode JWTs with HMAC SHA-256, ECDSA, and RSA signing.
• Refresh Token Support – Securely generate and validate refresh tokens.
• Expiration Handling – Automatically checks if a token is expired.
• Token Blacklist – Prevent the use of revoked tokens.
• base64 URL-Safe Encoding – Secure encoding and decoding for JWTs and refresh tokens.
• Multiple Signing Algorithms – Supports HMAC, ECDSA, and RSA for signing JWTs.
• Kotlin Multiplatform Support – Now available for JVM, iOS, macOS, and other platforms.

🚀 Usage

Encoding a JWT

To encode a JWT, you need to create a JwtPayload and use the encodeJwt function:

import com.jonathansteele.kojwt.*

val payload = JwtPayload(
    sub = "user123",
    exp = System.currentTimeMillis() / 1000 + 3600  // Expire in 1 hour
)
val secret = "your-secret-key"

val jwt = encodeJwt(payload, secret)
println("Encoded JWT: $jwt")

Decoding a JWT

To decode a JWT, use the decodeJwt function:

val decodedPayload = decodeJwt(jwt, secret)
println("Decoded Payload: $decodedPayload")

Encoding a Refresh Token

You can encode a refresh token using the encodeRefreshToken function:

val refreshTokenPayload = RefreshTokenPayload(
    sub = "user123",
    exp = System.currentTimeMillis() / 1000 + 86400  // Expire in 24 hours
)
val refreshToken = encodeRefreshToken(refreshTokenPayload, secret)
println("Encoded Refresh Token: $refreshToken")

Decoding a Refresh Token

To decode a refresh token, use the decodeRefreshToken function:

val decodedRefreshToken = decodeRefreshToken(refreshToken, secret)
println("Decoded Refresh Token: $decodedRefreshToken")

Blacklisting Tokens

You can add tokens to the blacklist to prevent further use:

TokenBlacklist.revoke(jwt)
TokenBlacklist.revoke(refreshToken)

🛣 Roadmap

• Kotlin Multiplatform support for additional targets

Contributions 🤝

This project is a work in progress, and contributions are welcome! Feel free to:

• Submit issues for bugs or feature suggestions
• Open pull requests to contribute directly