jwt

Package jwt

This package provides functions to create, parse, and verify JWT (JSON Web Tokens) using the github.com/golang-jwt/jwt/v5 library.

Types

1. Payload

A struct representing the payload claims for a JWT token.

Fields:

• PlayerID string: The player ID associated with the token.
• ServerGroup string: The server group associated with the token.

Functions

1. CreateToken

Creates and signs a new JWT token using the provided key and payload.

Parameters:

• key []byte: Secret key used for signing the token.
• payload Payload: The payload containing player ID and server group information.

Returns:

• A string representing the signed JWT token.
• An error if any occurs during token creation or signing.

Example Usage:

key := []byte("my_secret_key")
playerID := "12345"
serverGroup := "groupA"

payload := Payload{
    PlayerID:    playerID,
    ServerGroup: serverGroup,
}

tokenString, err := CreateToken(key, payload)
if err != nil {
    log.Fatalf("Failed to create token: %v", err)
}
fmt.Println(tokenString)

2. CheckSignature

Verifies the signature of a JWT token using the provided key.

Parameters:

• tokenString string: The JWT token to verify.
• key []byte: Secret key used for signing the token.

Returns:

• A boolean indicating whether the token's signature is valid.
• An error if any occurs during verification.

Example Usage:

tokenString := "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9..."
key := []byte("my_secret_key")

valid, err := CheckSignature(tokenString, key)
if err != nil {
    log.Fatalf("Failed to check token signature: %v", err)
}
fmt.Println(valid) // true or false

3. ParseUnverified

Parses a JWT token without verifying its signature.

Parameters:

• tokenString string: The JWT token to parse.

Returns:

• A Payload struct containing the parsed claims.
• An error if any occurs during parsing.

Example Usage:

tokenString := "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9..."

payload, err := ParseUnverified(tokenString)
if err != nil {
    log.Fatalf("Failed to parse unverified token: %v", err)
}
fmt.Println(payload.PlayerID) // "player_id_value"

4. ParseToken

Parses and verifies a JWT token using the provided key.

Parameters:

• tokenString string: The JWT token to parse.
• key []byte: Secret key used for signing the token.

Returns:

• A Payload struct containing the parsed claims.
• An error if any occurs during parsing or verification.

Example Usage:

tokenString := "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9..."
key := []byte("my_secret_key")

payload, err := ParseToken(tokenString, key)
if err != nil {
    log.Fatalf("Failed to parse token: %v", err)
}
fmt.Println(payload.PlayerID) // "player_id_value"

Notes:

• CreateToken: This function creates a new JWT token with the specified payload and signs it using HMAC SHA256.

• CheckSignature: It verifies if the provided JWT token is signed correctly without extracting any claims from it.

• ParseUnverified: Parses a JWT token but does not verify its signature. Use this for scenarios where you only need to extract claims without verifying them.

• ParseToken: Parses and verifies a JWT token using the specified key, ensuring that the token's signature matches before returning the payload claims.