javascript - Promise moving onto next .then() before resolving? -

i have simple web app logging onto customer facing webservers , downloading log files on request. when send request route module initiates connects via sftp webserver , downloads logs locally, 2 separate servers. reason last then() method in chain getting triggered before promise resolves.

router.js:

var express = require('express'); var router = express.router(); var gather = require('../api/gather'); /* home page. */ router.get('/', function(req, res, next) {   res.render('home'); }); router.get('/api/gather',function(req,res,next){   console.log('sending web9 target');   gather.logs(['web9'])     .then((logsfound)=>{       console.log('sending web 11 target');       gather.logs(['web11',logsfound])   })   .then((logsfound)=>{     console.log(logsfound);     console.log('downloading finished rendering home message');     res.render('home',{message: logsfound+' log files ready pickup'});   })     .catch((e)=>{     res.render('home',{message: e});     });  }); module.exports = router; 

/api/gather.js

//require ftp modules , define client let client = require('ssh2-sftp-client'); let sftp = new client(); var fs = require('fs'); let sftp2 = new client(); //set server configs var boomeconfig = {     host: process.env.ftp_host,     port: process.env.ftp_port,     username: process.env.ftp_user,     password: process.env.ftp_pass }; var webserverconfig = {     port: process.env.web_port,     username: process.env.web_user,     password: process.env.web_pass }; let message; const logdir = '/opt/foobar/logs/'; module.exports.logs = function(req, res){     console.log('hit gather module');     const target = req[0];     let logsfound = req[1] || 0;     return new promise((resolve,reject)=>{             if(target === 'web9'){                 webserverconfig.host = process.env.web9_host;             }else if(target === 'web11'){                 webserverconfig.host = process.env.web11_host;                 }else{                 message = 'no server target found';                 resolve(message);             }                 sftp.connect(webserverconfig)             .then(()=>{                 return sftp.list(logdir);             })             .then((data)=>{                 for(var = 0; < data.length; i++){                     const remotefilename = logdir + data[i].name;                     const localfilename = './downloads/'+target+'/' + data[i].name;                     //console.log('saving file '+localfilename);                     sftp.get(remotefilename).then((stream) => {                         stream.pipe(fs.createwritestream(localfilename));                     });                 }                 console.log('found '+data.length+' logs on '+target);                 sftp.end();                 logsfound += data.length;                 console.log('got '+target+' files moving next');                 if(target ==='web11'){                     console.log('total count '+logsfound);                 }             }).then((logsfound)=>{                 resolve(logsfound);             })             .catch((e)=>{                 console.log('error: '+e);                 reject(e);                 });     })     } 

my home route getting rendered logsfound undefined.

the thing can think of possible

sftp.get(remotefilename).then((stream) => {                         stream.pipe(fs.createwritestream(localfilename));                     }); 

is still streaming files when promise resolves.

issue was resolving promises way route written creating promise constructor antipattern. bergi , kevin b.

edited route

    var express = require('express');     var router = express.router();     var gather = require('../api/gather');     /* home page. */     router.get('/', function(req, res, next) {       res.render('home');     });     router.get('/api/gather',function(req,res,next){       console.log('sending web9 target');       return gather.logs(['web9'])         .then((logsfound)=>{           console.log('sending web 11 target');           return gather.logs(['web11',logsfound])       })       .then((logsfound)=>{         console.log(logsfound);         console.log('downloading finished rendering home message');         res.render('home',{message: logsfound+' log files ready pickup'});       })         .catch((e)=>{         res.render('home',{message: e});         });      });     module.exports = router;