Basic backend with Node, Express, and MongoDB
In my last post, I introduced some of the most common concepts of Node. Now, let’s create something more useful, a local database and API.
The repo is in the following link
https://github.com/delgadociteriowa/node-01-basic-backend
For the database, there are many different options, but for this tutorial, we will be using MongoDB:
Create a new folder ‘api-rest’ (or with another name), and create a now node project with npm init. Once it is created, in order to develop an API in an easy way, we will need a popular framework, Express.
npm install express — save
With express, with just a few lines of code, we can have a server up and running:
Inside the project, index.js:
‘use strict’
const express = require(‘express’);
const app = express();
app.listen(5000, () => {
console.log(‘API Running in localhost 5000’)
})
Console:
node index.js
In order to interact with a database, first, you must start the database system, in this case mongo:
Console:
mongod
Our API will need a library for easily connect to the database system. In order to connect with Mongo, we will need to install mongoose:
npm i -S mongoose
Once mongoose is installed, you will need to connect your API with Mongo. The following code is an example of that:
mongoose.connect(‘mongodb://localhost:27017/shop’, (err, res) => {
if (err) {
return console.log(‘DB connection error: ‘, err)
}
console.log(‘DB Connected’);
app.listen(5000, () => {
console.log(`API Running in localhost ${port}`);
})
})
Before going directly to the CRUD part of our API, first, let’s create a model folder with the Schema of objects we want to store in the database. For this example, the objects are going to be products for a store:
models/product.js
‘use strict’
const mongoose = require(‘mongoose’);
const Schema = mongoose.Schema;
const ProductSchema = Schema({
name: String,
picture: String,
price: { type: Number, default: 0},
category: {
type: String,
enum: [‘computers’, ‘phones’, ‘accesories’]
},
description: String
});
module.exports = mongoose.model(‘Product’, ProductSchema);
Then we import the product Schema in our index.js:
const mongoose = require(‘mongoose’);
const Product = require(‘./models/product’);
So now, we can use it in our get, post, put and delete methods:
app.get(‘/api/product’, (req, res) => {
Product.find({}, (err, products) => {
if (err) return res.status(500).send({ message: `Request error: ${err}`});
if (!products) return res.status(404).send({message: ‘There are no existances’});
res.status(200).send({ products })
})
});
The other methods are in the repository.
And this is basically all you need in order to create a basic RESTful API.
Happy Hacking!
