How to convert this Java code to JavaScript?

public static String getSignature(String skey, String iv, String data) throws Exception {
  IvParameterSpec Ⅳ = new IvParameterSpec(iv.getBytes("utf-8"));
  DESKeySpec desKey = new DESKeySpec(skey.getBytes("utf-8"));
  SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
  SecretKey key = keyFactory.generateSecret(desKey);
  Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
  cipher.init(Cipher.ENCRYPT_MODE, key, Ⅳ);
  byte[] databyte = cipher.doFinal(data.getBytes("utf-8"));
  return new String(Base64.getEncoder().encode(databyte));
}

I tried it myself and the result is:

  function getSignature(
    skey,
    iv,
    data,
  ) {
    const IV = Buffer.from(ivString, 'utf-8');
    const desKey = Buffer.from(skey, 'utf-8');

    const cipher = crypto.createCipheriv('des-cbc', desKey, IV);
    let encrypted = cipher.update(data, 'utf-8', 'base64');
    encrypted += cipher.final('base64');
    return encrypted;
  }

But I am getting ERR_CRYPTO_INVALID_KEYLEN error because my key length is not 8. I'm guessing that my JavaScript code is missing this part of Java code, but I don't know how to translate this part to JavaScript... :

SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
  SecretKey key = keyFactory.generateSecret(desKey);