How to link a collection with user? - node.js

Question

I am working on MEAN application(Angular2+). I want to maintain a seprate data for each user. As of now the data are like anyone can view any of the details but i want like, If i login and enter details, only I can view those details. Basically I want to link user collection with other collection. Since I am new to Mongo, I have no idea about this.
user.ts
import * as mongoose from 'mongoose'
const userSchema = new mongoose.Schema({
username: String,
email: { type: String, unique: true, lowercase: true, trim: true },
password: String,
role: String
});
cat.ts
import * as mongoose from 'mongoose';
const catSchema = new mongoose.Schema({
name : String,
height: String,
weight: String,
});
I have no idea what is this
base.ts
abstract class BaseCtrl {
abstract model: any;
// Get all
getAll = (req, res) => {
this.model.find({}, (err, docs) => {
if (err) { return console.error(err); }
res.json(docs);
});
}
// Count all
count = (req, res) => {
this.model.count((err, count) => {
if (err) { return console.error(err); }
res.json(count);
});
}
// Insert
insert = (req, res) => {
const obj = new this.model(req.body);
obj.save((err, item) => {
// 11000 is the code for duplicate key error
if (err && err.code === 11000) {
res.sendStatus(400);
}
if (err) {
return console.error(err);
}
res.status(200).json(item);
});
}
// Get by id
get = (req, res) => {
this.model.findOne({ _id: 'req.params.id '}, (err, obj) => {
if (err) { return console.error(err); }
res.json(obj);
});
}
// Update by id
update = (req, res) => {
this.model.findOneAndUpdate({ _id: req.params.id }, req.body, (err) => {
if (err) { return console.error(err); }
res.sendStatus(200);
});
}
// Delete by id
delete = (req, res) => {
this.model.findOneAndRemove({ _id: req.params.id }, (err) => {
if (err) { return console.error(err); }
res.sendStatus(200);
});
}
}
export default BaseCtrl;
Reference project : https://github.com/DavideViolante/Angular-Full-Stack

Answer 1

You need to add user_id field to catSchema. The user_id will be the reference for the user who add/save that cat.
cat.ts
import * as mongoose from 'mongoose';
const catSchema = new mongoose.Schema({
name : String,
height: String,
weight: String,
user_id: String, // Or may be ObjectId
});
And you need to query the user from users collection to retrieve the data everytime.
Or you can use DBRef of mongodb. To implement this in mongoose you can follow this link.
Basically your cat model will be
cat.ts
import * as mongoose from 'mongoose';
const catSchema = new mongoose.Schema({
name : String,
height: String,
weight: String,
user: { type: mongoose.Schema.ObjectId, ref: 'User' }
});
To insert the cat, get the userid from login details/sessions and add to collection.
For you, you need to add the 'user' field to req.body as in base controller you are creating model from req.body.
If you don't want to add to req.body, you can override the insert method for cat controller and manually create the cat model with userid.
controller/cat.ts
import Cat from '../models/cat';
import BaseCtrl from './base';
export default class CatCtrl extends BaseCtrl {
model = Cat;
insert = (req, res) => {
const data = {
title: req.body.title,
height: req.body.height,
weight: req.body.weight,
user: getUser() // Get the logged in userid
};
const obj = new this.model(data);
obj.save((err, item) => {
if (err && err.code === 11000) {
res.sendStatus(400);
}
if (err) {
return console.error(err);
}
res.status(200).json(item);
})
}
}
Just like above, you can modify and filter all your documents according to user.
Edit:
To make it simple, send the current logged in user in the form itself. cats.component.ts
addCat() {
this.addCatForm.value.userid = this.authService.currentUser._id; // You might need to use callback here
... // All other code
}
Revert the cat controller to as it was before.