[轉]datatable datatables nodejs

https://newcodingera.com/datatables-server-side-processing-using-nodejs-mysql/

https://1drv.ms/u/s!At2KEcnT9DVaiw88MAEXeML0bRf3

Important! SqlInjection

======================
datatables mongodb
https://github.com/deepikagunda/datatables

[轉]secp256k1簽章的message，長度都必須是256 bits，也就是32 bytes

https://medium.com/@antonassocareer/web3-secp256k1-%E7%B0%BD%E7%AB%A0%E8%88%87solidity%E9%A9%97%E7%AB%A0-26ded518cfdc

那麼如果我們想要單純用私鑰簽章一段資料，不要有Ethereum定義的那些prefix的話，就必須要直接調用 secp256k1 這一包library了。不過在用之前要知道，所有要丟給secp256k1簽章的message，長度都必須是256 bits，也就是32 bytes。剛剛我們說web3的簽名函式丟什麼都可以，是因為它會幫我加上prefix之後再做sha3 Hash (keccak)，最後一定會變成一個32 bytes的東西。如果我們自己純靠私要簽章訊息的話，也勢必要先通過這個函式來整理input長度

sha3 Hash (keccak)

bip39 mnemonic bip32 seed ed25519 elliptic

const bip39 = require('bip39')
const bip32 = require('bip32');
const EC = require('elliptic').ec;

json =`test json file`
mnemonic = "簡 熙 夢 幾 聲 可 高 汪 煙 版 統 仇"
path = "m/2018'/5'/1'/0/1"

const sJWSinit = async () => {
  console.log('-----sJWS Initial Start----- \n');

  dkey = await DeriveKey(mnemonic, path)
  console.log("\nGet dkey: %o \n", dkey)
  
  console.log('\n-----elliptic ed25519 Start----- \n');

  var EdDSA = require('elliptic').eddsa
  var ec = new EdDSA('ed25519');
  var eckeypair = ec.keyFromSecret(dkey.privateKey)
  
  var privateKeyHex = new Buffer.from(eckeypair.getSecret()).toString('hex')
  var publickeyHex = new Buffer.from(eckeypair.getPublic()).toString('hex')
  console.log("private key hex: %o", privateKeyHex)
  console.log("public key hex: %o\n", publickeyHex)

  var signature = eckeypair.sign(json).toHex();
  console.log("signature: %o\n", signature)

  var ec2 = new EdDSA('ed25519');
  var ec2keypair2 = ec2.keyFromPublic(publickeyHex, 'hex');
  console.log("EdDSA json verify: %o", ec2keypair2.verify(json, signature));
}

(async () => {
  console.log("--- aysnc sJWS init---")
  await sJWSinit();
})();

async function DeriveKey(mnemonic, derivePath) {
  if (bip39.validateMnemonic(mnemonic)) { console.log("mnemonic is fake!") }

  return bip39.mnemonicToSeed(mnemonic).then((vseed)=>{
    var root = bip32.fromSeed(vseed)
    var PathNode = root.derivePath(derivePath)
        
    console.log("# PATH 是 m/2018'/5'/1'/0/1/0  因為底下為derive(0)，所以 path + '/0' \n")
    console.log("privateKey (Hex): %o", PathNode.derive(0).privateKey.toString('hex'))
    console.log("publicKey (Hex): %o", PathNode.derive(0).publicKey.toString('hex')) // 024ac10a81e3a0f86cb4dad68c6a26031d805a057f36048f80a5b91b1c2cb0588c 符合

    return {
      prv_buf: PathNode.derive(0).privateKey,
      pub_buf: PathNode.derive(0).publicKey,
      wif: PathNode.derive(0).toWIF(),
      publicKey: PathNode.derive(0).publicKey.toString('hex'),
      privateKey: PathNode.derive(0).privateKey.toString('hex'),
      path: derivePath
    }
  }).catch((e) => {
    console.error('handle error here: ', e.message)
  })
     
}