系统稳定高可用的方案以及用户密码验证函数

fun checkPW(id: String, pwd: String, encodedPwd: String): Boolean {
    if(id.isEmpty() || pwd.isEmpty() || encodedPwd.isEmpty()) return false
    return encodedPwd == (id.md5() + pwd.md5()).sha1()
}
fun String.md5(): String {
    val digest = MessageDigest.getInstance("MD5")
    val result = digest.digest(this.toByteArray())
    return toHex(result)
}
fun String.sha1(): String {
    val digest = MessageDigest.getInstance("SHA-1")
    val result = digest.digest(this.toByteArray())
    return toHex(result)
}
private fun toHex(result: ByteArray): String {
    return with(StringBuilder()) {
        result.forEach {
            val hex = it.toInt() and (0xff)
            val hexStr = hex.toString()
            if (hexStr.length == 1) {
                append("0").append(hexStr)
            } else {
                append(hexStr)
            }
        }
        toString()
    }
}