How to perform database related code in model - node.js

Question

I am .NET developer and learning MEAN stack, developing an API for simple post and comment app. I am using MVC pattern without view as it is API. Here is how I am trying to create my model function :
const User = module.exports = mongoose.model('User',UserSchema);
module.exports.getUsers = function(callback){
User.find()
.exec(function(err,list_users){
if(err) { callback(); }
return list_users;
});
}
And here is the controller :
exports.user_list = function(req,res,next){
User.getUsers((err,list_users) => {
if(err){ next(err);}
res.json({user_list : list_users});
})
}
I am getting an error as getUsers is not getting imported. I am trying here to separate the data access code from controller and make controller only to manage request and response as I have been doing in .NET. Any help how can I achieve this?

Answer 1

I would look through the documentation to get familiar with how to use mongoose.
First thing I see is that you are not defining the methods correctly according to the documentation here http://mongoosejs.com/docs/guide.html#methods.
But you do not have to define a find() function. Mongoose already has it built in.
So the next step would be how are you creating the instance of the Model in your controller.
Your model should be:
const mongoose = require('mongoose'),
UserSchema = mongoose.Schema();
const User = new UserSchema({
// define user
});
module.exports = mongoose.model('User',UserSchema);
And the controller:
const User = require('path_to_User_model');
exports.user_list = function(req,res,next){
User.find((err,result)=>{
if(err)
// log err and send response
else
// send the result ex: res.json(result);
});
}
also read through the setup on the npmjs website. https://www.npmjs.com/package/mongoose
So to create have your data functions and have your controller use that function you may try
const mongoose = require('mongoose'),
UserSchema = mongoose.Schema();
const User = new UserSchema({
// define user
});
// data functions
User.methods.getUsers = function (){
User.find((err,result)=>{
if(err)
// log err and return something
return false;
else
return result;
});
}
module.exports = mongoose.model('User',UserSchema);
then the controller
const User = require('path_to_User_model');
exports.user_list = function(req,res,next){
var users = User.getUsers();
if (!users)
res.status(500).send('error_page');
else
res.json(users);
}