node.js - NodeJS: How to use for async helper method for async method -

i'm using async library asynchronous programming on nodejs. want make helper method (that use async method), rather put code in same place.

here sample code:

var solve = function() {   async.waterfall([       // long working task. huh       function (callback) {           settimeout(function() {               console.log('hello world!');               callback();           }, 2000);       },        function (callback) {           authorservice.helperasync();       },        function (callback) {           settimeout(function() {               console.log('bye bye!');           }, 2000);       }    ]); };  solve(); 

in other file, make async function:

var helperasync = function() {     async.waterfall([        function(callback) {            console.log('task 1');            callback();        },         function (callback) {             console.log('task 2');             callback();         }     ]); } 

i want result should be:

hello world task 1 task 2 bye bye 

but output

hello world task 1 task 2 

. how can fix code ?

thanks :)

you need setup each file used module, involves exporting function you'd return, so:

solve.js

var async = require('async'); var helperasync = require('./helperasync.js');    module.exports = function solve() {      async.waterfall([          function helloone(next) {             settimeout(function() {                 console.log('hello world!');                 return next();             }, 2000);         },          function helpercall(next) {             helperasync(params, function(){                return next();             });         },          function byebye(next) {             settimeout(function() {                 console.log('bye bye!');                 return next();             }, 2000);         }     ], function(result){       return result;     });    }; 

helperasync.js

var async = require('async');  module.exports = function helperasync (params, callback) {    async.waterfall([       function(next) {          console.log('task 1');          return next();        },         function (next) {           console.log('task 2');           return next();         }   ], function(result){       return callback(result);   });  }; 

i've renamed callback async.waterfall next in order prevent confusion main callback of module.