返回promise节点js

Question

我有一个值seed，它返回一个promise，我需要将它传递给将使用该输出的hdkey函数。

seed返回一个promise，然后抛出一个异常，因为我需要那个未包装的响应。

我看了一些关于它的其他帖子，我想知道我试图设置的值(root)会被用于后续命令。

我应该继续做.then()吗？

var bip39 = require('bip39');
var hdkey = require('hdkey');
var createHash = require('create-hash');
//var btcLib = require('bitcoinjs-lib');
var bs58check = require('bs58check');

//const mnemonic = bip39.generateMnemonic(); //generates string
const mnemonic = "gentle mutual speak consider mandate kingdom cash explain soul exile cabin squeeze";
const seed = bip39.mnemonicToSeed(mnemonic)
                  .then(a => ); //creates seed buffer
console.log('Seed: ' + seed);
console.log('mnemonic: ' + mnemonic);

const root = hdkey.fromMasterSeed(seed);
const masterPrivateKey = root.privateKey.toString('hex');

Answer 1

您需要等待Promise来获取seed缓冲区：

const bip39 = require('bip39')
const hdkey = require('hdkey');

const mnemonic = "gentle mutual speak consider mandate kingdom cash explain soul exile cabin squeeze";
bip39.mnemonicToSeed(mnemonic)
  .then(seed => {
    console.log('Seed: ', seed);
    console.log('mnemonic: ', mnemonic);

    const root = hdkey.fromMasterSeed(seed);
    const masterPrivateKey = root.privateKey.toString('hex');
    console.log(masterPrivateKey);
  })
  .catch(err => {
    console.error('error to seed', err)
  })

或者使用bip39.mnemonicToSeedSync方法来避免使用Promise接口-但性能较差

const bip39 = require('bip39')
const hdkey = require('hdkey');

const mnemonic = "gentle mutual speak consider mandate kingdom cash explain soul exile cabin squeeze";
const seed = bip39.mnemonicToSeedSync(mnemonic)

console.log('Seed: ', seed);
console.log('mnemonic: ', mnemonic);

const root = hdkey.fromMasterSeed(seed);
const masterPrivateKey = root.privateKey.toString('hex');
console.log(masterPrivateKey);