javascript - Last callback not being called using async -

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i cannot seem last callback (commented "optional callback") called send result browser. pointers doing wrong? using following modules: async, restify , postgresql node.js

console.log('start');  var async = require('async'); var restify = require('restify'); var server = restify.createserver(); server.use(restify.bodyparser());  server.get('/user/creationdate/:username', function(req, res, next) {     var username = req.params.username;     var record;      async.parallel([         function(callback){             getuserbyname(username, function(err, user) {                 if (err) return callback(err);                 record = user;             });         }     ], // optional callback         function(err){             console.log('5. following record has been retrieved:' + record);             res.send(record);         });      next(); });  server.listen(8080, function () {     console.log('%s listening @ %s', server.name, server.url); });  handleerror = function handleerror(err) {     if(!err) { return false; }     else {         console.log('the following error occurred:' + err);      }     return true; };  function getpgclient(){     var pg = require('pg');      var client = new pg.client({         user: 'postgres',         password: 'password',         database: 'foobar',         host: '192.168.1.100',         port: 5432     });      client.on('drain', client.end.bind(client)); //disconnect client when queries finished      return client; }  function getuserbyname(username, callback){     var client = getpgclient();     console.log('2. trying connect db');      client.connect(function(err) {         console.log('3. error connecting db:' + handleerror(err));         if(handleerror(err)) return callback(err);          client.query("select created_at users username='" + username + "'", function(err, result) {             if(handleerror(err)) return;             console.log('4. error occurred:' + err);             console.log(result);             console.log(callback);             callback(null, result);         })     }); }

i'm not sure why you're using async since you're calling 1 asynchronous function. reason callback isn't called because you're not ending first function calling callback: 

async.parallel([   function(callback) {     getuserbyname(username, function(err, user) {       // call async callback err , user       callback(err, user);     });   } ], function(err, record) {   console.log('5. following record has been retrieved:' + record);   res.send(record); });

or, shorter:

async.parallel([   function(callback) {     getuserbyname(callback);   } ], function(err, record) {   console.log('5. following record has been retrieved:' + record);   res.send(record); });

or, in case, shorter (and without need async):

getuserbyname(function(err, record) {   // handle error, or ...   console.log('5. following record has been retrieved:' + record);   res.send(record); });

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