(Swift 3,4,5...) Duplicate Java HMAC-SHA1 using Chilkat

This example uses Chilkat to produce the same results as this Java code:

import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.binary.Hex;

import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
import java.security.InvalidKeyException;
import java.security.Key;
import java.security.NoSuchAlgorithmException;

public void hmacSignatureExample() throws NoSuchAlgorithmException,
InvalidKeyException {

final String method = "POST";
final Long epoch = 1456765639015L; // Hardcoding for this example
final String uri = "/api/v5/policy/1234567890";
final String newline = "\n";

final String privateKey = "qwfvUeVRWAwyjlAzGivefFPTg+m6QtBPmDVv7Ra
/u7K3UuVVRhrZ/qc8EPh8IGJatuxsWD4EX+D9qE/eVvLTpw==";
final String publicKey = "16baedbe244b6c063968850716afb319a";

// Prepare the signature
final String plainText = method + newline + epoch + newline + uri + newline;

// Hash the plaintext with the private key
final byte[] keyBytes = privateKey.getBytes();
final Key key = new SecretKeySpec(keyBytes, 0, keyBytes.length, "HmacSHA1");
final Mac mac = Mac.getInstance("HmacSHA1");
mac.init(key);
String signatureHash = new String(Hex.encodeHex(mac.doFinal(plainText.
getBytes())));

// Prefix with public key
signatureHash = publicKey + ":" + signatureHash;

// Base64 encode to produce AUTHORIZATION
final String authorization = new String(Base64.encodeBase64(signatureHash.
getBytes()));
}

Chilkat Downloads for the Swift Programming Language MAC OS X (Cocoa) Objective-C/Swift Libs iOS Objective-C/Swift Libs

func chilkatTest() {
    // This example assumes the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    var success: Bool

    // This is clearly in base64 encoding.
    var privateKey: String? = "qwfvUeVRWAwyjlAzGivefFPTg+m6QtBPmDVv7Ra/u7K3UuVVRhrZ/qc8EPh8IGJatuxsWD4EX+D9qE/eVvLTpw=="

    // This is clearly in the hex encoding.
    var publicKey: String? = "16baedbe244b6c063968850716afb319a"

    var plainText: String? = "POST\n1456765639015\n/api/v5/policy/1234567890\n"

    let crypt = CkoCrypt2()!

    // We want HMAC-SHA1.
    crypt.macAlgorithm = "HMAC"
    crypt.hashAlgorithm = "SHA1"

    // The Java code (above) is literally using the us-ascii chars of the base64 string as the HMAC key.
    // (It is NOT using the base64 decoded bytes.)
    crypt.setMacKeyEncoded(privateKey, encoding: "us-ascii")

    // We want our HMAC-SHA1 output to be a hex string.
    crypt.encodingMode = "hex_lower"

    var hmacHex: String? = crypt.macStringENC(plainText)

    print("\(hmacHex!)")

    // The expected result is: dd3e8440f6b550f152156ea5e12d3e20b262adae

    let sbSignatureHash = CkoStringBuilder()!
    sbSignatureHash.append(publicKey)
    sbSignatureHash.append(":")
    sbSignatureHash.append(hmacHex)

    var authorization: String? = sbSignatureHash.getEncoded("base64", charset: "utf-8")
    print("Authorization: \(authorization!)")

    // The expected result is:  MTZiYWVkYmUyNDRiNmMwNjM5Njg4NTA3MTZhZmIzMTlhOmRkM2U4NDQwZjZiNTUwZjE1MjE1NmVhNWUxMmQzZTIwYjI2MmFkYWU=

}