How Can I Properly Call A List Of Async Functions In Order?

I am attempting to write a 'robocopy /mir' like function within Node.js and cannot seem to wrap my head around how to properly execute several async functions in order. Some backgr

Solution 1:

Maybe something like that will do the trick :

var $j = function(val, space) {
  returnJSON.stringify(val, null, space || '')
}
var log = function(val) {
  document.body.insertAdjacentHTML('beforeend', '<div><pre>' + val + '</div></pre>')
}



var files = '12345'.split('').map(function(v) {
  return {
    name: 'file_' + v + '.js',
    load: function() {
      var cur = this;
      var pro = newPromise(function(resolve, reject) {

        log('loading : ' + cur.name);
        
        // we simualate the loading stuffsetTimeout(function() {
          resolve(cur.name);
        }, 1 * 1000);

      }).then( function( val ) {
        
        // once loaded log('loaded : ' + val);
        return val;
      
      });

      return pro;

    }
  };
});


files.reduce(function(t, v) {

  t.promise = t.promise.then(function(){ 
      return v.load();
  });
  
  return t;
}, {
  promise: Promise.resolve(1)
});

Solution 2:

Use async.eachSeries on arrays, or async.forEachOfSeries on objects.

Looping an object

varasync = require('async');
var filesObject = {'file/path/1': {}, 'file/path/2': {}};

async.forEachOfSeries(filesObject, copyFileFromObj, allDone);

functioncopyFileFromObj(value, key, callback) {
  console.log('Copying file ' + key + '...');
  callback(); // when done
}

functionallDone(err) {
  if (err) {
    console.error(err.message);
  }
  console.log('All done.');
}                

Looping an array

varasync = require('async');
var filesArray = ['file/path/1', 'file/path/2'];

async.eachSeries(filesArray, copyFile, allDone);

functioncopyFile(file, callback) {
  console.log('Copying file ' + file + '...');
  callback(); // when done
}

functionallDone(err) {
  if (err) {
    console.error(err.message);
  }
    console.log('All done.');
}

Working example here: https://tonicdev.com/edinella/sync-loop-of-async-operations