Callback Hell Async/Await

callback-hell-async.js

const AWS = require(`aws-sdk`)
const fs = require(`fs`)
const path = require(`path`)

const dir = `./sample-dir`
const bucket = `bucket-name`

const s3bucket = new AWS.S3({params: {Bucket: bucket}})

async function readDirAsync(path) {

  return new Promise(function (resolve, reject) {
    fs.readdir(path, function (error, result) {
      if (error) {
        reject(error);
      } else {
        resolve(result);
      }
    })
  })

}

function readFileAsync(path) {

  return new Promise(function (resolve, reject) {
    fs.readFile(path, function (error, result) {
      if (error) {
        reject(error)
      } else {
        resolve(result)
      }
    })
  })

}

function s3UploadAsync(params){
 return new Promise(function (resolve, reject) {
   s3bucket.upload(params, function (error, result) {
      if (error) {
        reject(error)
      } else {
        resolve(result)
      }
    })
  })
}

async function unlinkAsync(path) {
  return new Promise(function (resolve, reject) {
    fs.unlink(path, function (error, result) {
      if (error) {
        reject(error)
      } else {
        resolve(result)
      }
    })
  })
}

async function start(){ 
    const files = await readDirAsync(dir)    
    files.forEach( async (fileName, fileIndex) => {
        const filePath = path.resolve(dir, fileName)
        const data = await readFileAsync(`${filePath}`)
        const params = {
            Key: fileName, 
            Body: data
        };
        await s3UploadAsync(params)
        await unlinkAsync(filePath)
    })
}

start()