javaimport java.security.MessageDigest;

public class CheckSumBuilder {
    // 计算并获取CheckSum
    public static String getCheckSum(String appSecret, String nonce, String curTime) {
        return encode("sha1", appSecret + nonce + curTime);
    }
    
    // 计算并获取md5值
    public static String getMD5(String requestBody) {
        return encode("md5", requestBody);
    }

    private static String encode(String algorithm, String value) {
        if (value == null) {
            return null;
        }
        try {
            MessageDigest messageDigest
                    = MessageDigest.getInstance(algorithm);
            messageDigest.update(value.getBytes());
            return getFormattedText(messageDigest.digest());
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
    private static String getFormattedText(byte[] bytes) {
        int len = bytes.length;
        StringBuilder buf = new StringBuilder(len * 2);
        for (int j = 0; j < len; j++) {
            buf.append(HEX_DIGITS[(bytes[j] >> 4) & 0x0f]);
            buf.append(HEX_DIGITS[bytes[j] & 0x0f]);
        }
        return buf.toString();
    }
    private static final char[] HEX_DIGITS = { '0', '1', '2', '3', '4', '5',
            '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
}

const { SHA1 } = require("crypto-js");

function randString(x) {
  let s = "";
  while (s.length < x && x > 0) {
    const v = Math.random() < 0.5 ? 32 : 0;
    s += String.fromCharCode(
      Math.round(Math.random() * (122 - v - (97 - v)) + (97 - v))
    );
  }
  return s;
}

const [Nonce, CurTime] = [randString(20), new Date().getTime().toString().slice(0, 10)]

function CheckSum(AppSecret, Nonce, CurTime) {
  return SHA1(AppSecret + Nonce + CurTime);
}