javascript - TypeError: undefined is not a function in Node.js -

in group model, i'm exporting 1 function pass result of query using callback.

in router file, i'm calling function, after requiring other file.

that's ./models/groups.js:

var groupschema = new mongoose.schema({  [...]  module.exports.getall =  function(cb) {     groupschema.find({}, function(err, groups) {         if (err) return cb(err)         cb(null, groups)     }) }  [...]  module.exports = mongoose.model('group', groupschema); 

and that's ./routes/groups.js file.

var group = require('../models/group') router.route('/groups')      .get(function(req, res, next) {         group.getall( function(err, group){             if (err) res.send(err)             res.send(group)         })     })  [...] 

this not working, because every time make request, i'm getting typeerror: undefined not function error. know can make query right on router file, think separating things between routes , methods better practice.

you're overwriting object defined getall function when assign new value module.exports.

you've got 2 options:

1. extend model getall function, , export today.
   looks like:

   var model = mongoose.model('group', groupschema); model.getall = function(cb) {   ... }; module.exports = model; 

   but that's not "clean".

2. export model under named property alongside getall function.
   looks this:

   module.exports.getall = function(cb) {   ... }; module.exports.model = mongoose.model('group', groupschema); 

   then in routes, you'd have:

   var groups = require('../models/group'); // have groups.getall & groups.model 

   this more flexible overall , allow export other types/functions/values see fit.