javascript–nodejs异步到同步

我是nodejs和Javascript的新手,我正在开发一个开源项目,因为昨晚我试图将这个函数从异步转换为同步,但我不能,我使用async / await但我认为我不太了解这个概念,这个函数使用aes256算法加密和压缩文件,我的工作异常,但我想添加这个新功能,允许你递归地加密目录的内容.

function encrypt({ file, password }, error_callback, succ_callback) {
const initVect = crypto.randomBytes(16);
// Generate a cipher key from the password.
const CIPHER_KEY = crypto.createHash('sha256').update(password).digest();;
const readStream = fs.createReadStream(file);
const gzip = zlib.createGzip();
const cipher = crypto.createCipheriv('aes-256-cbc', CIPHER_KEY, initVect);
const appendInitVect = new AppendInitVect(initVect);
// Create a write stream with a different file extension.
const writeStream = fs.createWriteStream(path.join(file + ".dnc"));
readStream
.pipe(gzip)
.pipe(cipher)
.pipe(appendInitVect)
.pipe(writeStream);
readStream.on('error', error_callback);
readStream.on('end', succ_callback);
}


解决方法:

尝试使用promises.通过稍微更改代码,您可以宣传该功能,然后在采取行动之前等待所有承诺解决或拒绝.

function encrypt({ file, password }) {
const initVect = crypto.randomBytes(16);
// Generate a cipher key from the password.
const CIPHER_KEY = crypto.createHash('sha256').update(password).digest();;
const readStream = fs.createReadStream(file);
const gzip = zlib.createGzip();
const cipher = crypto.createCipheriv('aes-256-cbc', CIPHER_KEY, initVect);
const appendInitVect = new AppendInitVect(initVect);
// Create a write stream with a different file extension.
const writeStream = fs.createWriteStream(path.join(file + ".dnc"));
readStream
.pipe(gzip)
.pipe(cipher)
.pipe(appendInitVect)
.pipe(writeStream);
const promise = new Promise();
writeStream.on('error', err => promise.reject(err));
writeStream.on('end', data => promise.resolve(data));
return promise;
}
const promise1 = encrypt({file1, password1});
const promise2 = encrypt({file2, password2});
Promise.all([promise1, promise2])
.then(succ_callback)
.catch(error_callback);


我没有运行此代码,因此可能需要进行一些调整以使其工作,但这是一般要点.