Sign a JWS with an HMAC Key

See more JSON Web Signatures (JWS) Examples

Demonstrates Jws.SetMacKey, which sets the symmetric MAC key for a signature. The key bytes are supplied in a named encoding such as hex or base64.

func chilkatTest() {
    var success: Bool = false

    let jws = CkoJws()!

    //  Protected header specifying HMAC-SHA256.
    let header = CkoJsonObject()!
    header.updateString(jsonPath: "alg", value: "HS256")
    success = jws.setProtectedHeader(index: 0, json: header)
    if success == false {
        print("\(jws.lastErrorText!)")
        return
    }

    var bIncludeBom: Bool = false
    success = jws.setPayload(payload: "This is the content to sign.", charset: "utf-8", includeBom: bIncludeBom)
    if success == false {
        print("\(jws.lastErrorText!)")
        return
    }

    //  Set the symmetric MAC key for signature 0.  The key bytes are provided in the named encoding (here
    //  base64).  In production, obtain the key from a secure source rather than hard-coding it.
    var base64Key: String? = "YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4eXowMTIzNDU="
    success = jws.setMacKey(index: 0, key: base64Key, encoding: "base64")
    if success == false {
        print("\(jws.lastErrorText!)")
        return
    }

    var jwsCompact: String? = jws.create()
    if jws.lastMethodSuccess == false {
        print("\(jws.lastErrorText!)")
        return
    }

    print("\(jwsCompact!)")

}