digest ';' ALGORITHM ';' FILE

static final String _digestHelp = "${digest;<algo>;<in>}, get a digest (e.g. MD5, SHA-256) of a file";

/**
 * Get a digest of a file.
 *
 * @throws NoSuchAlgorithmException
 * @throws IOException
 */
public String _digest(String... args) throws NoSuchAlgorithmException, IOException {
    verifyCommand(args, _digestHelp, null, 3, 3);

    MessageDigest digester = MessageDigest.getInstance(args[1]);
    File f = domain.getFile(args[2]);
    IO.copy(f, digester);
    byte[] digest = digester.digest();
    return Hex.toHexString(digest);
}