Francesco Ciulla
Francesco Ciulla

Follow

Francesco Ciulla

Follow
JavaScript CRUD Rest API using Nodejs, Express, Sequelize,  Postgres, Docker and Docker Compose

JavaScript CRUD Rest API using Nodejs, Express, Sequelize, Postgres, Docker and Docker Compose

Here is a step-by-step procedure from scratch that will guide through the process of creating the APIS and dockerize the project

Francesco Ciulla's photo
Francesco Ciulla
ยทJan 13, 2021ยท

7 min read

Let's create a CRUD rest API in JavaScript, using:

  • Node.js

  • Express

  • Sequelize

  • Postgres

  • Docker

  • Docker Compose

If you prefer a video version:

Intro

Here is a schema of the architecture of the application we are going to create:

crud, read, update, delete, to a node.js app and postgres service, connected with docker compose. POstman and tableplus to test it

We will create 5 endpoints for basic CRUD operations:

  • Create

  • Read all

  • Read one

  • Update

  • Delete

We will create a Node.js application using:

  • Express as a framework

  • Sequelize as an ORM

  1. We will Dockerize the Node.js application

  2. We will have a Postgres istance, we will test it with Tableplus

  3. We will create a docker compose file to run both the services

  4. We will test the APIs with Postman


Step-by-step guide

Here is a step-by step guide.

create a new folder

mkdir node-crud-api

step into it

cd node-crud-api

initialize a new npm project

npm init -y

install the dependencies

npm i express pg sequelize
  • express is the Node.js framework

  • pg is a driver for a connection with a Postgres db

  • sequelize is the ORM so we avoid typing SQL queries

create 4 folders

mkdir controllers routes util models

Open the folder with your favorite IDE. If you have Visual Studio Code, you can type this from the terminal:

code .

You should now have a folder similar to this one:

controller, routes, model, util folder, a node_modules and package.json file, package-lock.json file

Now let's start coding.

Database connection

Create a file called "database.js" inside the "util" folder.

This file will contain the internal configuration to allow the connection between the Node.js application and the running Postgres instance.

Populate the util/database.js file

const Sequelize = require('sequelize');

const sequelize = new Sequelize(
    process.env.PG_DB,
    process.env.PG_USER,
    process.env.PG_PASSWORD,
    {
        host: process.env.PG_HOST,
        dialect: 'postgres',
    }
);

module.exports = sequelize;

User model

Create a file called "user.js" inside the "models" folder.

This file will contain the model, in this case a user with an auto-incremented id, a name and an email.

Populate the models/user.js file:

const Sequelize = require('sequelize');
const db = require('../util/database');

const User = db.define('user', {
    id: {
        type: Sequelize.INTEGER,
        autoIncrement: true,
        allowNull: false,
        primaryKey: true
    },
    name: Sequelize.STRING,
    email: Sequelize.STRING
});

module.exports = User;

Controllers

This is the file that contains all the functions to execute in order to interact with the database and have the 4 basic functionalities:

Create a file called "users.js" inside the "controllers" folder

Populate the controllers/users.js file

const User = require('../models/user');

// CRUD Controllers

//get all users
exports.getUsers = (req, res, next) => {
    User.findAll()
        .then(users => {
            res.status(200).json({ users: users });
        })
        .catch(err => console.log(err));
}

//get user by id
exports.getUser = (req, res, next) => {
    const userId = req.params.userId;
    User.findByPk(userId)
        .then(user => {
            if (!user) {
                return res.status(404).json({ message: 'User not found!' });
            }
            res.status(200).json({ user: user });
        })
        .catch(err => console.log(err));
}

//create user
exports.createUser = (req, res, next) => {
  const name = req.body.name;
  const email = req.body.email;
  User.create({
    name: name,
    email: email
  })
    .then(result => {
      console.log('Created User');
      res.status(201).json({
        message: 'User created successfully!',
        user: result
      });
    })
    .catch(err => {
      console.log(err);
    }); 
}

//update user
exports.updateUser = (req, res, next) => {
  const userId = req.params.userId;
  const updatedName = req.body.name;
  const updatedEmail = req.body.email;
  User.findByPk(userId)
    .then(user => {
      if (!user) {
        return res.status(404).json({ message: 'User not found!' });
      }
      user.name = updatedName;
      user.email = updatedEmail;
      return user.save();
    })
    .then(result => {
      res.status(200).json({message: 'User updated!', user: result});
    })
    .catch(err => console.log(err));
}

//delete user
exports.deleteUser = (req, res, next) => {
  const userId = req.params.userId;
  User.findByPk(userId)
    .then(user => {
      if (!user) {
        return res.status(404).json({ message: 'User not found!' });
      }
      return User.destroy({
        where: {
          id: userId
        }
      });
    })
    .then(result => {
      res.status(200).json({ message: 'User deleted!' });
    })
    .catch(err => console.log(err));
}

Routes

Create a file called "users.js" inside the "routes" folder.

Populate the routes/users.js file

const controller = require('../controllers/users');
const router = require('express').Router();

// CRUD Routes /users
router.get('/', controller.getUsers); // /users
router.get('/:userId', controller.getUser); // /users/:userId
router.post('/', controller.createUser); // /users
router.put('/:userId', controller.updateUser); // /users/:userId
router.delete('/:userId', controller.deleteUser); // /users/:userId

module.exports = router;

Index file

To run our application we need to create on more file at the root level. this is the file that will be executed by the docker container.

in the root folder, create a file called index.js

Populate the "index.js file":

const express = require('express');
const bodyparser = require('body-parser');
const sequelize = require('./util/database');
const User = require('./models/user');

const app = express();

app.use(bodyparser.json());
app.use(bodyparser.urlencoded({ extended: false }));

app.use((req, res, next) => {
  res.setHeader('Access-Control-Allow-Origin', '*');
  res.setHeader('Access-Control-Allow-Methods', 'GET, POST, PUT, DELETE');
  next();
});

//test route
app.get('/', (req, res, next) => {
  res.send('Hello World');
});

//CRUD routes
app.use('/users', require('./routes/users'));

//error handling
app.use((error, req, res, next) => {
  console.log(error);
  const status = error.statusCode || 500;
  const message = error.message;
  res.status(status).json({ message: message });
});

//sync database
sequelize
  .sync()
  .then(result => {
    console.log("Database connected");
    app.listen(3000);
  })
  .catch(err => console.log(err));

Docker Part

Let's create 3 more files at the root level:

  • .dockerignore (it starts with a dot)

  • Dockerfile (capital D)

  • docker-compose.yml

The structure should look like this:

Image description

the .dockerignore will contain a single line:

node_modules

the .dockerignore file with a single line: node_modules


The Dockerfile

To create a Docker image we need a simple yet powerfule file. That's called "Dockerfile" (capital D). We might use a different name but let's keep things simple for now.

FROM node:14

# Create app directory
WORKDIR /app

COPY package*.json ./

RUN npm install

# Bundle app source
COPY . .

EXPOSE 3000

CMD [ "node", "index.js" ]

Docker compose file

To run multiple services an easy way is to create a file called "docker-compose.yml"

The docker-compose.yml file:

version: "3.9"

services:
  node_app:
    container_name: node_app
    build: .
    image: francescoxx/node_live_app
    ports:
      - "3000:3000"
    environment:
      - PG_DB=node_live_db
      - PG_USER=francesco
      - PG_PASSWORD=12345
      - PG_HOST=node_db
    depends_on:
      - node_db

  node_db:
    container_name: node_db
    image: postgres:12
    ports:
      - "5432:5432"
    environment:
      - POSTGRES_DB=node_live_db
      - POSTGRES_USER=francesco
      - POSTGRES_PASSWORD=12345
    volumes:
      - node_db_data:/var/lib/postgresql/data

volumes:
  node_db_data: {}

Build the Docker image and run the docker containers

Run Postgres in a container

First, let's run the postgres container:

docker compose up -d node_db

To check the logs, we can type:

docker compose logs

you should get an output similar to this one:

..... 2023-02-12 13:07:41.342 UTC [1] LOG:  database system is ready to accept connections

if we see "database system is ready to accept connections" we are good to go!

Let's test it using TablePlus.

Click on the + to create a new connection

Image description

copy the values from the docker-compose.yml file. (password is 12345 if you left the values as they are)

Image description

Build and run the Docker service

Second, let's build our Docker iamge:

docker compose build

Image description

finally, let's start the service:

docker compose up node_app

This should be the output on the terminal

Image description

Test the app with Postman

Let's test the app using Postman.

Make a GET request to localhost:3000

Image description

Make a GET request to localhost:3000/users

We should have an empty array as a response

Image description

Let's create 3 users: aaa, bbb, and ccc

Image description

Image description

Image description

Let's check again all the users:

Make a GET request to localhost:3000/users

We should see 3 users:

Image description

Let's get a single user, for example the user 2

Make a GET request to localhost:3000/users/2

Image description

Let's update an existing user, for example the same user 2

Make a PUT reqeust to localhost:3000/users/2 with a different body

Image description

Finally, let's delete the user number 3

Make a DELETE reuqest to localhost:3000/users/3

Image description

We can also check the values using TablePlus

Image description

Conclusion

This is a basic example of building a CRUD rest API using Node.js, Express, Sequelize, Postres, Docker, and Docker Compose.

All the code is available in the GitHub repository: https://github.com/FrancescoXX/crud-node-live

For a video version: If you prefer a video version:

That's all. If you have any questions, drop a comment below.

Francesco

Did you find this article valuable?

Support Francesco Ciulla by becoming a sponsor. Any amount is appreciated!

See recent sponsors |ย Learn more about Hashnode Sponsors
ย 
Share this