Node.js - Express Persistent Session Store with PostgreSQL + Sequelize

Node.js - Express Persistent Session Store with PostgreSQL + Sequelize

Node.js - Express Persistent Session Store with PostgreSQL + Sequelize

Your application may use session to authenticate user. If you're using Node.js, the most popular option to implement session is using a library called Passport.js. The problem is by default sessions are not stored persistently. If the application is restarted, all sessions will be lost. The easiest way to store sessions persistently is by using database to store them. In this tutorial, I'm going to show you how to store session persistently to PostgreSQL database with Sequelize as the ORM.

Add Dependencies to Your Project

Below are the dependencies you'll need to follow this tutorial. Add them to your package.json and run npm install.

package.json

{
"dependencies": {
"bcrypt": "~3.0.0",
"bluebird": "~3.5.1",
"connect-session-sequelize": "~6.0.0",
"dotenv": "~6.1.0",
"express-session": "~1.15.6",
"lodash": "~4.17.11",
"passport": "~0.4.0",
"passport-local": "~1.0.0",
"sequelize": "~4.38.0"
}
}

Edit your .env

Put these variables on your .env file and adjust the values according to your database setup. In addition to database config, you also need to set a session secret.

DATABASE_NAME=your_db_name
DATABASE_USERNAME=your_db_username
DATABASE_PASSWORD=your_db_password
DATABASE_HOST=your_db_ip
DATABASE_PORT=your_db_port
SESSION_SECRET=randomstringabcde123

Create Singleton Sequelize Object

You only need to create a singleton connection object to the same database and use the same object anywhere you need it.

utils/sequelize-singleton.js

require('dotenv').config();

const Sequelize = require('sequelize');

const self = module.exports;
let sequelize;

/**
 * Construct a singleton sequelize object to query the database
 * 
 * @returns {object} - Sequelize object
 */
exports.initialize = () => {
if (!sequelize) {
 const dbName = process.env.DATABASE_NAME;
 const dbUsername = process.env.DATABASE_USERNAME;
 const dbPassword = process.env.DATABASE_PASSWORD;
 const dbHost = process.env.DATABASE_HOST;
 const dbPort = process.env.DATABASE_PORT;
return new Sequelize(dbName, dbUsername, dbPassword, {
host: dbHost,
port: dbPort,
dialect: 'postgres',
});
}

return sequelize;
};

module.exports = self.initialize();

Create User Model

The user data is stored in database, so you need to define the model for it. We use bcrypt to hash the password which is done inside beforeSave hook. There is also compareMethod prototype function used to check whether a given password matches the hashed value stored in database.

models/User.js

const _ = require('lodash');
const bcrypt = require('bcrypt');
const Bluebird = require('bluebird');
const Sequelize = require('sequelize');

const sequelize = require('../singleton/sequelize-singleton');

const mappings = {
userId: {
type: Sequelize.UUID,
primaryKey: true,
defaultValue: Sequelize.DataTypes.UUIDV4,
},
name: {
type: Sequelize.TEXT,
allowNull: false,
},
email: {
type: Sequelize.TEXT,
allowNull: false,
unique: true,
},
password: {
type: Sequelize.TEXT,
allowNull: false,
},
};

const User = sequelize.define('User', mappings, {
indexes: [
{
name: 'user_userId_index',
method: 'BTREE',
fields: ['userId'],
},
{
name: 'user_email_index',
method: 'BTREE',
fields: ['email'],
},
{
name: 'user_role_index',
method: 'BTREE',
fields: ['role'],
},
{
name: 'user_status_index',
method: 'BTREE',
fields: ['status'],
},
],
});

User.prototype.comparePassword = function (password) { // eslint-disable-line func-names
return Bluebird.resolve()
.then(() => bcrypt.compareSync(password, this.password))
.catch((err) => {
console.log(err);

return false;
});
};

User.hook('beforeSave', (user) => {
user.name = _.trim(user.name);

if ((user.previous('password') !== user.password) && (!_.isEmpty(user.password))) {
const salt = bcrypt.genSaltSync(10);
const hash = bcrypt.hashSync(user.password, salt);
user.password = hash;
}

return user;
});

exports.getMapping = () => mappings;

exports.getModel = () => User;

Create Query Helpers

In order to get user data from database, we need to use some queries. First for getting user by ID (used to deserialize user) and the other is for getting user by email (used on login).

queries/user.js

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

exports.getUserById = userId => User.findOne({
where: { userId },
});

exports.getUserByEmail = email => User.findOne({
where: { email },
});

Create Passport.js Configuration.

To use Passport.js, we need to create the configuration by implementing required methods (serializeUser and deserializeUser) and defining the authentication strategy we want to use. In this tutorial, we use local authentication using passport-local.

config/passport.js

const Bluebird = require('bluebird');
const LocalStrategy = require('passport-local').Strategy;

const userQueries = require('../queries/user');

module.exports = (passport) => {
passport.serializeUser((user, done) => {
done(null, user.userId);
});

passport.deserializeUser((id, done) => Bluebird.resolve()
.then(async () => {
const user = await userQueries.getUserById(id);

done(null, user);
})
.catch(done));

passport.use('local', new LocalStrategy(
{
usernameField: 'email',
passwordField: 'password',
passReqToCallback: true,
},
(req, email, password, done) => Bluebird.resolve()
.then(async () => {
const user = await userQueries.getUserByEmail(email);

if (!user || !await user.comparePassword(password)) {
return done(null, null);
}

return done(null, user);
})
.catch(done),
));
};

Create Session Model

As you need to store session in database and use Sequelize as the ORM, you need to create a model for the session. The table has 3 columns:

  • sid (STRING) : The session ID
  • expires (DATE): Time when the token becomes expired
  • data (STRING): Contains cookie data and user ID in JSON format. Example: {"cookie":{"originalMaxAge":2592000000,"expires":"2018-12-22T07:29:53.051Z","httpOnly":true,"path":"/"},"passport":{"user":"4b946762-b931-4bc2-b285-0a7464ad3c3a"}}
const Sequelize = require('sequelize');

const sequelize = require('../singleton/sequelizeSingleton');

/**
 * Sessions table is used to store user session persistently.
 * 
 *
   * Read more on https://www.npmjs.com/package/connect-session-sequelize
 */
const mappings = {
sid: {
type: Sequelize.STRING,
primaryKey: true,
},
expires: Sequelize.DATE,
data: Sequelize.STRING(50000),
};

const Session = sequelize.define('Session', mappings, {
indexes: [
{
name: 'session_sid_index',
method: 'BTREE',
fields: ['sid'],
},
],
});

exports.getMapping = () => mappings;

exports.getModel = () => Session;

Add Controllers to Handle Sign In and Sign Out

Of course we need to create a controller to handle sign in and another one to handle sign out. Below is the controller for sign in. It authenticates user by using local strategy (the name of the strategy must match what we've already defined on passport configuration). Every time a user successfully logged in, a new session is regenerated for that user.

routes/sign-in.js

const Bluebird = require('bluebird');
const passport = require('passport');

/**
 * Authenticate with passport.
 * @param {Object} req
 * @param {Object} res
 * @param {Function} next
 */
const authenticate = (req, res, next) => new Bluebird((resolve, reject) => {
passport.authenticate('local', (err, user) => {
if (err) {
return reject(err);
}

return resolve(user);
})(req, res, next);
});

/**
 * Login
 * @param {Object} req
 * @param {Object} user
 */
const login = (req, user) => new Bluebird((resolve, reject) => {
req.login(user, (err) => {
if (err) {
return reject(err);
}

return resolve();
});
});

/**
 * Regenerate user session.
 * @param {Object} req
 */
const regenerateSession = req => new Bluebird((resolve, reject) => {
req.session.regenerate((err) => {
if (err) {
return reject(err);
}

return resolve();
});
});

/**
 * Save user session.
 * @param {Object} req
 */
const saveSession = req => new Bluebird((resolve, reject) => {
req.session.save((err) => {
if (err) {
return reject(err);
}

return resolve();
});
});

/**
 * HTTP handler for sign in.
 *
 * @param {Object} req
 * @param {Object} res
 * @param {Function} next
 */
module.exports = (req, res, next) => Bluebird.resolve()
.then(async () => {
const user = await authenticate(req, res, next);

if (!user) {
return res.status(401).send('Invalid email or password');
}

await login(req, user);
const temp = req.session.passport;

await regenerateSession(req);
req.session.passport = temp;

await saveSession(req);

return res.send();
})
.catch(next);

The logout controller is very simple, just make the session expired by calling req.logout().

routes/sign-out.js

/**
 * HTTP handler for sign out.
 *
 * @param {Object} req
 * @param {Object} res
 */
module.exports = (req, res) => {
req.logout();

res.send();
};

Use Passport.js and Session Store on Your Application

Finally, load the Passport.js configurtaion in your application. Then use express-session along with the configuration. To save sessions persistently, you need to add store configuration with a new instance of connect-session-sequelize. As for db, pass the sequelize singletion object, while the table should be filled with the name of the table that stores the sessions - in this tutorial the table name is Session. Don't forget to load the models of Staff and Session beforehand.

app.js

const app = require('express')();
const session = require('express-session');

const passport = require('passport');
const SequelizeStore = require('connect-session-sequelize')(session.Store);

const passportConfig = require('./config/passport');
const sequelize = require('./utils/sequelize-singleton');

require('./models/Staff');
require('./models/Session');

passportConfig(passport);
app.use(session({
secret: process.env.SESSION_SECRET,
resave: false,
saveUninitialized: false,
cookie: {
maxAge: 30 * 24 * 60 * 60 * 1000, // 1 month
},
store: new SequelizeStore({
db: sequelize,
table: 'Session',
}),
}));
app.use(passport.initialize());
app.use(passport.session());

app.post('/sign-in', require('./routes/sign-in'));
app.post('/sign-out', require('./routes/sign-out'));

Now you can try the code by sending HTTP request to the sign in and sign out endpoints. If it works, you should see user session stored in Sessions table. The session of a user will become expired if the user calls the sign out endpoint.

That's all about how to store session persistently in PostgreSQL database using Passport authentication and Sequelize ORM.

Secure Node.js, Express.js and PostgreSQL API using Passport.js

Secure Node.js, Express.js and PostgreSQL API using Passport.js

The comprehensive step by step tutorial on building secure Node.js, Express.js, Passport.js, and PostgreSQL Restful Web Service

The comprehensive step by step tutorial on building secure Node.js, Express.js, Passport.js, and PostgreSQL Restful Web Service. Previously, we have shown you a combination of Node.js, Express.js, and PostgreSQL tutorial. Now, we just add a security for that RESTful Web Service endpoints. Of course, we will start this tutorial from scratch or from zero application. We will use JWT for this Node.js, Express.js, Passport.js, and PostgreSQL tutorial.

Table of Contents:

The following tools, frameworks, and modules are required for this tutorial:

We assume that you have installed PostgreSQL server in your machine or can use your own remote server (we are using PostgreSQL 9.5.13). Also, you have installed Node.js in your machine and can run node, npm or yarn command in your terminal or command line. Next, check their version by type this commands in your terminal or command line.

node -v
v8.12.0
npm -v
6.4.1
yarn -v
1.10.1

That the versions that we are uses. Let’s continue with the main steps.

1. Create Express.js Project and Install Required Modules

Open your terminal or node command line the go to your projects folder. First, install express generator using this command.

sudo npm install express-generator -g

Next, create an Express.js app using this command.

express secure-node --view=ejs

This will create Express.js project with the EJS view instead of Jade view template because using ‘–view=ejs’ parameter. Next, go to the newly created project folder then install node modules.

cd secure-node && npm install

You should see the folder structure like this.

There’s no view yet using the latest Express generator. We don’t need it because we will create a RESTful API.

2. Add and Configure Sequelize.js Module and Dependencies

Before installing the modules for this project, first, install Sequelize-CLI by type this command.

sudo npm install -g sequelize-cli

To install Sequelize.js module, type this command.

npm install --save sequelize

Then install the module for PostgreSQL.

npm install --save pg pg-hstore

Next, create a new file at the root of the project folder.

touch .sequelizerc

Open and edit that file then add this lines of codes.

const path = require('path');

module.exports = {
  "config": path.resolve('./config', 'config.json'),
  "models-path": path.resolve('./models'),
  "seeders-path": path.resolve('./seeders'),
  "migrations-path": path.resolve('./migrations')
};

That files will tell Sequelize initialization to generate config, models, seeders and migrations files to specific directories. Next, type this command to initialize the Sequelize.

sequelize init

That command will create config/config.json, models/index.js, migrations and seeders directories and files. Next, open and edit config/config.json then make it like this.

{
  "development": {
    "username": "djamware",
    "password": "[email protected]@r3",
    "database": "secure_node",
    "host": "127.0.0.1",
    "dialect": "postgres"
  },
  "test": {
    "username": "root",
    "password": "[email protected]@r3",
    "database": "secure_node",
    "host": "127.0.0.1",
    "dialect": "postgres"
  },
  "production": {
    "username": "root",
    "password": "[email protected]@r3",
    "database": "secure_node",
    "host": "127.0.0.1",
    "dialect": "postgres"
  }
}

We use the same configuration for all the environment because we are using the same machine, server, and database for this tutorial.

Before run and test connection, make sure you have created a database as described in the above configuration. You can use the psql command to create a user and database.

psql postgres --u postgres

Next, type this command for creating a new user with password then give access for creating the database.

postgres-# CREATE ROLE djamware WITH LOGIN PASSWORD '[email protected]@r3';
postgres-# ALTER ROLE djamware CREATEDB;

Quit psql then log in again using the new user that previously created.

postgres-# \q
psql postgres -U djamware

Enter the password, then you will enter this psql console.

psql (9.5.13)
Type "help" for help.

postgres=>

Type this command to creating a new database.

postgres=> CREATE DATABASE secure_node;

Then give that new user privileges to the new database then quit the psql.

postgres=> GRANT ALL PRIVILEGES ON DATABASE secure_node TO djamware;
postgres=> \q

3. Create or Generate Models and Migrations

We will use Sequelize-CLI to generating a new model. Type this command to create a model for Products and User model for authentication.

sequelize model:create --name Product --attributes prod_name:string,prod_desc:string,prod_price:float
sequelize model:create --name User --attributes username:string,password:string

That command creates a model file to the model’s folder and a migration file to folder migrations. Next, modify models/user.js and then import this module.

var bcrypt = require('bcrypt-nodejs');

Add the new methods to the User model, so the user.js class will be like this.

module.exports = (sequelize, DataTypes) => {
  const User = sequelize.define('User', {
    username: DataTypes.STRING,
    password: DataTypes.STRING
  }, {});
  User.beforeSave((user, options) => {
    if (user.changed('password')) {
      user.password = bcrypt.hashSync(user.password, bcrypt.genSaltSync(10), null);
    }
  });
  User.prototype.comparePassword = function (passw, cb) {
    bcrypt.compare(passw, this.password, function (err, isMatch) {
        if (err) {
            return cb(err);
        }
        cb(null, isMatch);
    });
  };
  User.associate = function(models) {
    // associations can be defined here
  };
  return User;
};

For the models/product.js there’s no action needed, leave it as default generated the model class.

4. Create Routers for RESTful Web Service and Authentication

To authenticating users and secure the resources or endpoint create this file as a router.

touch routes/api.js

Open and edit routes/api.js then declares all require variables.

const express = require('express');
const jwt = require('jsonwebtoken');
const passport = require('passport');
const router = express.Router();
require('../config/passport')(passport);
const Product = require('../models').Product;
const User = require('../models').User;

Create a router for signup or register the new user.

router.post('/signup', function(req, res) {
  console.log(req.body);
  if (!req.body.username || !req.body.password) {
    res.status(400).send({msg: 'Please pass username and password.'})
  } else {
    User
      .create({
        username: req.body.username,
        password: req.body.password
      })
      .then((user) => res.status(201).send(user))
      .catch((error) => {
        console.log(error);
        res.status(400).send(error);
      });
  }
});

Create a router for sign in or login with username and password.

router.post('/signin', function(req, res) {
  User
      .find({
        where: {
          username: req.body.username
        }
      })
      .then((user) => {
        if (!user) {
          return res.status(401).send({
            message: 'Authentication failed. User not found.',
          });
        }
        user.comparePassword(req.body.password, (err, isMatch) => {
          if(isMatch && !err) {
            var token = jwt.sign(JSON.parse(JSON.stringify(user)), 'nodeauthsecret', {expiresIn: 86400 * 30});
            jwt.verify(token, 'nodeauthsecret', function(err, data){
              console.log(err, data);
            })
            res.json({success: true, token: 'JWT ' + token});
          } else {
            res.status(401).send({success: false, msg: 'Authentication failed. Wrong password.'});
          }
        })
      })
      .catch((error) => res.status(400).send(error));
});

Create a secure router to get and post product data.

router.get('/product', passport.authenticate('jwt', { session: false}), function(req, res) {
  var token = getToken(req.headers);
  if (token) {
    Product
      .findAll()
      .then((products) => res.status(200).send(products))
      .catch((error) => { res.status(400).send(error); });
  } else {
    return res.status(403).send({success: false, msg: 'Unauthorized.'});
  }
});

router.post('/product', passport.authenticate('jwt', { session: false}), function(req, res) {
  var token = getToken(req.headers);
  if (token) {
    Product
      .create({
        prod_name: req.body.prod_name,
        prod_desc: req.body.prod_desc,
        prod_price: req.body.prod_price
      })
      .then((product) => res.status(201).send(product))
      .catch((error) => res.status(400).send(error));
  } else {
    return res.status(403).send({success: false, msg: 'Unauthorized.'});
  }
});

Create a function for extract the token.

getToken = function (headers) {
  if (headers && headers.authorization) {
    var parted = headers.authorization.split(' ');
    if (parted.length === 2) {
      return parted[1];
    } else {
      return null;
    }
  } else {
    return null;
  }
};

Finally, export the router as a module.

module.exports = router;

5. Run and Test Secure Node.js, Express.js, Passport.js, and PostgreSQL Web Service

To run and test this secure Node.js, Express.js, Passport.js, and PostgreSQL Web Service, run the PostgreSQL instance first then run this command from the Terminal.

nodemon

or

npm start

To test the secure Product endpoint, open the Postman then type fill all required fields like this image.

You should get the response message Unauthorized and status code 401. Next, test signup using the Postman by changing the method to POST, add the address localhost:3000/api/signup, add the header Content-type with value application/json and the body of request raw text like this.

{ "username":"[email protected]", "password":"qqqq1111" }

You should get this response when executing successfully.

Next, test to log in with the above signed/registered username and password by changing the URL to localhost:3000/api/signin. You should get this response when executes successfully.

Now, you can back using the previous GET method with additional header using the token get from the sign in/log in response. You should see the Product data like below.

That it’s, the secure Node.js, Express.js, Passport.js, and PostgreSQL Web Service. You can get the working source code from our GitHub.

Learn More

The Complete Node.js Developer Course (2nd Edition)

Learn and Understand NodeJS

Node JS: Advanced Concepts

GraphQL: Learning GraphQL with Node.Js

Angular (Angular 2+) & NodeJS - The MEAN Stack Guide

The Complete Python & PostgreSQL Developer Course

SQL & Database Design A-Z™: Learn MS SQL Server + PostgreSQL

The Complete SQL Bootcamp

The Complete Oracle SQL Certification Course

How to Use Express.js, Node.js and MongoDB.js

How to Use Express.js, Node.js and MongoDB.js

In this post, I will show you how to use Express.js, Node.js and MongoDB.js. We will be creating a very simple Node application, that will allow users to input data that they want to store in a MongoDB database. It will also show all items that have been entered into the database.

In this post, I will show you how to use Express.js, Node.js and MongoDB.js. We will be creating a very simple Node application, that will allow users to input data that they want to store in a MongoDB database. It will also show all items that have been entered into the database.

Creating a Node Application

To get started I would recommend creating a new database that will contain our application. For this demo I am creating a directory called node-demo. After creating the directory you will need to change into that directory.

mkdir node-demo
cd node-demo

Once we are in the directory we will need to create an application and we can do this by running the command
npm init

This will ask you a series of questions. Here are the answers I gave to the prompts.

The first step is to create a file that will contain our code for our Node.js server.

touch app.js

In our app.js we are going to add the following code to build a very simple Node.js Application.

var express = require("express");
var app = express();
var port = 3000;
 
app.get("/", (req, res) => {
  res.send("Hello World");
});
 
app.listen(port, () => {
  console.log("Server listening on port " + port);
});

What the code does is require the express.js application. It then creates app by calling express. We define our port to be 3000.

The app.use line will listen to requests from the browser and will return the text “Hello World” back to the browser.

The last line actually starts the server and tells it to listen on port 3000.

Installing Express

Our app.js required the Express.js module. We need to install express in order for this to work properly. Go to your terminal and enter this command.

npm install express --save

This command will install the express module into our package.json. The module is installed as a dependency in our package.json as shown below.

To test our application you can go to the terminal and enter the command

node app.js

Open up a browser and navigate to the url http://localhost:3000

You will see the following in your browser

Creating Website to Save Data to MongoDB Database

Instead of showing the text “Hello World” when people view your application, what we want to do is to show a place for user to save data to the database.

We are going to allow users to enter a first name and a last name that we will be saving in the database.

To do this we will need to create a basic HTML file. In your terminal enter the following command to create an index.html file.

touch index.html

In our index.html file we will be creating an input filed where users can input data that they want to have stored in the database. We will also need a button for users to click on that will add the data to the database.

Here is what our index.html file looks like.

<!DOCTYPE html>
<html>
  <head>
    <title>Intro to Node and MongoDB<title>
  <head>

  <body>
    <h1>Into to Node and MongoDB<&#47;h1>
    <form method="post" action="/addname">
      <label>Enter Your Name<&#47;label><br>
      <input type="text" name="firstName" placeholder="Enter first name..." required>
      <input type="text" name="lastName" placeholder="Enter last name..." required>
      <input type="submit" value="Add Name">
    </form>
  <body>
<html>

If you are familiar with HTML, you will not find anything unusual in our code for our index.html file. We are creating a form where users can input their first name and last name and then click an “Add Name” button.

The form will do a post call to the /addname endpoint. We will be talking about endpoints and post later in this tutorial.

Displaying our Website to Users

We were previously displaying the text “Hello World” to users when they visited our website. Now we want to display our html file that we created. To do this we will need to change the app.use line our our app.js file.

We will be using the sendFile command to show the index.html file. We will need to tell the server exactly where to find the index.html file. We can do that by using a node global call __dirname. The __dirname will provide the current directly where the command was run. We will then append the path to our index.html file.

The app.use lines will need to be changed to
app.use("/", (req, res) => {   res.sendFile(__dirname + "/index.html"); });

Once you have saved your app.js file, we can test it by going to terminal and running node app.js

Open your browser and navigate to “http://localhost:3000”. You will see the following

Connecting to the Database

Now we need to add our database to the application. We will be connecting to a MongoDB database. I am assuming that you already have MongoDB installed and running on your computer.

To connect to the MongoDB database we are going to use a module called Mongoose. We will need to install mongoose module just like we did with express. Go to your terminal and enter the following command.
npm install mongoose --save

This will install the mongoose model and add it as a dependency in our package.json.

Connecting to the Database

Now that we have the mongoose module installed, we need to connect to the database in our app.js file. MongoDB, by default, runs on port 27017. You connect to the database by telling it the location of the database and the name of the database.

In our app.js file after the line for the port and before the app.use line, enter the following two lines to get access to mongoose and to connect to the database. For the database, I am going to use “node-demo”.

var mongoose = require("mongoose"); mongoose.Promise = global.Promise; mongoose.connect("mongodb://localhost:27017/node-demo");

Creating a Database Schema

Once the user enters data in the input field and clicks the add button, we want the contents of the input field to be stored in the database. In order to know the format of the data in the database, we need to have a Schema.

For this tutorial, we will need a very simple Schema that has only two fields. I am going to call the field firstName and lastName. The data stored in both fields will be a String.

After connecting to the database in our app.js we need to define our Schema. Here are the lines you need to add to the app.js.
var nameSchema = new mongoose.Schema({   firstName: String,   lastNameName: String });

Once we have built our Schema, we need to create a model from it. I am going to call my model “DataInput”. Here is the line you will add next to create our mode.
var User = mongoose.model("User", nameSchema);

Creating RESTful API

Now that we have a connection to our database, we need to create the mechanism by which data will be added to the database. This is done through our REST API. We will need to create an endpoint that will be used to send data to our server. Once the server receives this data then it will store the data in the database.

An endpoint is a route that our server will be listening to to get data from the browser. We already have one route that we have created already in the application and that is the route that is listening at the endpoint “/” which is the homepage of our application.

HTTP Verbs in a REST API

The communication between the client(the browser) and the server is done through an HTTP verb. The most common HTTP verbs are
GET, PUT, POST, and DELETE.

The following table explains what each HTTP verb does.

HTTP Verb Operation
GET Read
POST Create
PUT Update
DELETE Delete

As you can see from these verbs, they form the basis of CRUD operations that I talked about previously.

Building a CRUD endpoint

If you remember, the form in our index.html file used a post method to call this endpoint. We will now create this endpoint.

In our previous endpoint we used a “GET” http verb to display the index.html file. We are going to do something very similar but instead of using “GET”, we are going to use “POST”. To get started this is what the framework of our endpoint will look like.

app.post("/addname", (req, res) => {
 
});
Express Middleware

To fill out the contents of our endpoint, we want to store the firstName and lastName entered by the user into the database. The values for firstName and lastName are in the body of the request that we send to the server. We want to capture that data, convert it to JSON and store it into the database.

Express.js version 4 removed all middleware. To parse the data in the body we will need to add middleware into our application to provide this functionality. We will be using the body-parser module. We need to install it, so in your terminal window enter the following command.

npm install body-parser --save

Once it is installed, we will need to require this module and configure it. The configuration will allow us to pass the data for firstName and lastName in the body to the server. It can also convert that data into JSON format. This will be handy because we can take this formatted data and save it directly into our database.

To add the body-parser middleware to our application and configure it, we can add the following lines directly after the line that sets our port.

var bodyParser = require('body-parser');
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: true }));
Saving data to database

Mongoose provides a save function that will take a JSON object and store it in the database. Our body-parser middleware, will convert the user’s input into the JSON format for us.

To save the data into the database, we need to create a new instance of our model that we created early. We will pass into this instance the user’s input. Once we have it then we just need to enter the command “save”.

Mongoose will return a promise on a save to the database. A promise is what is returned when the save to the database completes. This save will either finish successfully or it will fail. A promise provides two methods that will handle both of these scenarios.

If this save to the database was successful it will return to the .then segment of the promise. In this case we want to send text back the user to let them know the data was saved to the database.

If it fails it will return to the .catch segment of the promise. In this case, we want to send text back to the user telling them the data was not saved to the database. It is best practice to also change the statusCode that is returned from the default 200 to a 400. A 400 statusCode signifies that the operation failed.

Now putting all of this together here is what our final endpoint will look like.

app.post("/addname", (req, res) => {
  var myData = new User(req.body);
  myData.save()
    .then(item => {
      res.send("item saved to database");
    })
    .catch(err => {
      res.status(400).send("unable to save to database");
    });
});
Testing our code

Save your code. Go to your terminal and enter the command node app.js to start our server. Open up your browser and navigate to the URL “http://localhost:3000”. You will see our index.html file displayed to you.

Make sure you have mongo running.

Enter your first name and last name in the input fields and then click the “Add Name” button. You should get back text that says the name has been saved to the database like below.

Access to Code

The final version of the code is available in my Github repo. To access the code click here. Thank you for reading !

Node, Express, PostgreSQL, Vue 2 and GraphQL CRUD Web App

Node, Express, PostgreSQL, Vue 2 and GraphQL CRUD Web App

A comprehensive step by step tutorial on building CRUD Web App using Node, Express, PostgreSQL, Vue 2 and Graphql CRUD Web App

A comprehensive step by step tutorial on building CRUD Web App using Node, Express, PostgreSQL, Vue 2 and Graphql CRUD Web App

For the client side (Vue 2) we will use Vue-Apollo module. For the backend side, we will use Node, Express, Sequelize, and PostgreSQL with Express-Graphql module and their dependencies. The scenario for this tutorial is simple as usual, just the CRUD operation which data accessible through GraphQL.

Table of Contents:
  • Create Express.js Application and Install Required Modules
  • Add and Configure Sequelize.js Module and Dependencies
  • Create or Generate Models and Migrations
  • Install GraphQL Modules and Dependencies
  • Create GraphQL Schemas for the Book
  • Add Mutation for CRUD Operation to the Schema
  • Test GraphQL using GraphiQL
  • Create Vue 2 Application
  • Install Required Modules, Dependencies, and Router
  • Create a Component to Display List of Books
  • Create a Component to Show and Delete Books
  • Create a Component to Add a New Book
  • Create a Component to Edit a Book
  • Run and Test GraphQL CRUD from the Vue 2 Application

The following tools, frameworks, and modules are required for this tutorial:

  • Node.js (choose recommended version)
  • Vue 2
  • Express.js
  • GraphQL
  • Express-GraphQL
  • Vue-Apollo
  • Bootstrap-Vue
  • Terminal (Mac/Linux) or Node Command Line (Windows)
  • IDE or Text Editor (We are using Visual Studio Code)

We assume that you have already Installed Node.js. Make sure Node.js command line is working (on Windows) or runnable in Linux/OS X terminal.

node -v
v10.15.1
npm -v
6.8.0
yarn -v
1.10.1

That the versions that we are uses. Let's continue with the main steps.

1. Create Express.js Application and Install Required Modules

Open your terminal or node command line the go to your projects folder. First, install express generator using this command.

sudo npm install express-generator -g

Next, create an Express.js app using this command.

express vue-graphql

This will create Express.js project with files and directories.

create : vue-graphql/
create : vue-graphql/public/
create : vue-graphql/public/javascripts/
create : vue-graphql/public/images/
create : vue-graphql/public/stylesheets/
create : vue-graphql/public/stylesheets/style.css
create : vue-graphql/routes/
create : vue-graphql/routes/index.js
create : vue-graphql/routes/users.js
create : vue-graphql/views/
create : vue-graphql/views/error.jade
create : vue-graphql/views/index.jade
create : vue-graphql/views/layout.jade
create : vue-graphql/app.js
create : vue-graphql/package.json
create : vue-graphql/bin/
create : vue-graphql/bin/www

Next, go to the newly created project folder then install node modules.

cd vue-graphql && npm install

There's no view yet using the latest Express generator. We don't need it because we will create a GraphQL server.

2. Add and Configure Sequelize.js Module and Dependencies

Before installing the modules for this project, first, install Sequelize-CLI by type this command.

sudo npm install -g sequelize-cli

To install Sequelize.js module, type this command.

npm install --save sequelize

Then install the module for PostgreSQL.

npm install --save pg pg-hstore

Next, create a new file at the root of the project folder.

touch .sequelizerc

Open and edit that file then add these lines of codes.

const path = require('path');

module.exports = {
  "config": path.resolve('./config', 'config.json'),
  "models-path": path.resolve('./models'),
  "seeders-path": path.resolve('./seeders'),
  "migrations-path": path.resolve('./migrations')
};

That files will tell Sequelize initialization to generate config, models, seeders and migrations files to specific directories. Next, type this command to initialize the Sequelize.

sequelize init

That command will create config/config.json, models/index.js, migrations and seeders directories and files. Next, open and edit config/config.json then make it like this.

{
  "development": {
    "username": "djamware",
    "password": "[email protected]@r3",
    "database": "node_sequelize",
    "host": "127.0.0.1",
    "dialect": "postgres"
  },
  "test": {
    "username": "root",
    "password": "[email protected]@r3",
    "database": "node_sequelize",
    "host": "127.0.0.1",
    "dialect": "postgres"
  },
  "production": {
    "username": "root",
    "password": "[email protected]@r3",
    "database": "node_sequelize",
    "host": "127.0.0.1",
    "dialect": "postgres"
  }
}

We use the same configuration for all the environment because we are using the same machine, server, and database for this tutorial.

Before run and test connection, make sure you have created a database as described in the above configuration. You can use the psql command to create a user and database.

psql postgres --u postgres

Next, type this command for creating a new user with password then give access for creating the database.

postgres-# CREATE ROLE djamware WITH LOGIN PASSWORD '[email protected]@r3';
postgres-# ALTER ROLE djamware CREATEDB;

Quit psql then log in again using the new user that previously created.

postgres-# \q
psql postgres -U djamware

Enter the password, then you will enter this psql console.

psql (9.5.13)
Type "help" for help.

postgres=>

Type this command to creating a new database.

postgres=> CREATE DATABASE book_store;

Then give that new user privileges to the new database then quit the psql.

postgres=> GRANT ALL PRIVILEGES ON DATABASE book_store TO djamware;
postgres=> \q

3. Create or Generate Models and Migrations

We will use Sequelize-CLI to generate a new model. Type this command to create a model for 'Book'.

sequelize model:generate --name Book --attributes isbn:string,title:string,author:string,description:string,publishedYear:integer,publisher:string

That commands will generate models and migration files. The content of the model file looks like this.

'use strict';
module.exports = (sequelize, DataTypes) => {
  const Book = sequelize.define('Book', {
    isbn: DataTypes.STRING,
    title: DataTypes.STRING,
    author: DataTypes.STRING,
    description: DataTypes.STRING,
    publishedYear: DataTypes.INTEGER,
    publisher: DataTypes.STRING
  }, {});
  Book.associate = function(models) {
    // associations can be defined here
  };
  return Book;
};

And the migration file looks like this.

'use strict';
module.exports = {
  up: (queryInterface, Sequelize) => {
    return queryInterface.createTable('Books', {
      id: {
        allowNull: false,
        autoIncrement: true,
        primaryKey: true,
        type: Sequelize.INTEGER
      },
      isbn: {
        type: Sequelize.STRING
      },
      title: {
        type: Sequelize.STRING
      },
      author: {
        type: Sequelize.STRING
      },
      description: {
        type: Sequelize.STRING
      },
      publishedYear: {
        type: Sequelize.INTEGER
      },
      publisher: {
        type: Sequelize.STRING
      },
      createdAt: {
        allowNull: false,
        type: Sequelize.DATE
      },
      updatedAt: {
        allowNull: false,
        type: Sequelize.DATE
      }
    });
  },
  down: (queryInterface, Sequelize) => {
    return queryInterface.dropTable('Books');
  }
};

Finally, for migrations, there's nothing to change and they all ready to generate the table to the PostgreSQL Database. Type this command to generate the table to the database.

sequelize db:migrate

4. Install GraphQL Modules and Dependencies

Now, the GraphQL time. Type this command to install GraphQL modules and it's dependencies.

npm install express express-graphql graphql graphql-date cors --save

Next, open and edit app.js then declare all of those modules and dependencies.

var graphqlHTTP = require('express-graphql');
var schema = require('./graphql/bookSchemas');
var cors = require("cors");

The schema is not created yet, we will create it in the next steps. Next, add these lines of codes for configuring GraphQL that can use over HTTP.

app.use('*', cors());
app.use('/graphql', cors(), graphqlHTTP({
  schema: schema,
  rootValue: global,
  graphiql: true,
}));

That's configuration are enabled CORS and the GraphiQL. GraphiQL is the user interface for testing GraphQL query.

5. Create GraphQL Schemas for the Book

Create a folder at the server folder for hold GraphQL Schema files then create a Javascript file for the schema.

mkdir graphql
touch graphql/bookSchemas.js

Next, open and edit server/graphql/bookSchemas.js then declares all required modules and models.

var GraphQLSchema = require('graphql').GraphQLSchema;
var GraphQLObjectType = require('graphql').GraphQLObjectType;
var GraphQLList = require('graphql').GraphQLList;
var GraphQLObjectType = require('graphql').GraphQLObjectType;
var GraphQLNonNull = require('graphql').GraphQLNonNull;
var GraphQLID = require('graphql').GraphQLID;
var GraphQLString = require('graphql').GraphQLString;
var GraphQLInt = require('graphql').GraphQLInt;
var GraphQLDate = require('graphql-date');
var BookModel = require('../models').Book;

Create a GraphQL Object Type for Book models.

var bookType = new GraphQLObjectType({
  name: "book",
  fields: function() {
    return {
      id: {
        type: GraphQLInt
      },
      isbn: {
        type: GraphQLString
      },
      title: {
        type: GraphQLString
      },
      author: {
        type: GraphQLString
      },
      description: {
        type: GraphQLString
      },
      publishedYear: {
        type: GraphQLInt
      },
      publisher: {
        type: GraphQLString
      },
      createdAt: {
        type: GraphQLDate
      },
      updatedAt: {
        type: GraphQLDate
      }
    };
  }
});

Next, create a GraphQL query type that calls a list of book and single book by ID.

var queryType = new GraphQLObjectType({
  name: 'Query',
  fields: function () {
    return {
      books: {
        type: new GraphQLList(bookType),
        resolve: function () {
          const books = BookModel.findAll({
            order: [
              ['createdAt', 'DESC']
            ],
          })
          if (!books) {
            throw new Error('Error')
          }
          return books
        }
      },
      book: {
        type: bookType,
        args: {
          id: {
            name: 'id',
            type: GraphQLString
          }
        },
        resolve: function (root, params) {
          const bookDetails = BookModel.findByPk(params.id).exec()
          if (!bookDetails) {
            throw new Error('Error')
          }
          return bookDetails
        }
      }
    }
  }
});

Finally, exports this file as GraphQL schema by adding this line at the end of the file.

module.exports = new GraphQLSchema({query: queryType});

6. Add Mutation for CRUD Operation to the Schema

For completing CRUD (Create, Read, Update, Delete) operation of the GraphQL, we need to add a mutation that contains create, update and delete operations. Open and edit graphql/bookSchemas.js then add this mutation as GraphQL Object Type.

var mutation = new GraphQLObjectType({
  name: 'Mutation',
  fields: function () {
    return {
      addBook: {
        type: bookType,
        args: {
          isbn: {
            type: new GraphQLNonNull(GraphQLString)
          },
          title: {
            type: new GraphQLNonNull(GraphQLString)
          },
          author: {
            type: new GraphQLNonNull(GraphQLString)
          },
          description: {
            type: new GraphQLNonNull(GraphQLString)
          },
          publishedYear: {
            type: new GraphQLNonNull(GraphQLInt)
          },
          publisher: {
            type: new GraphQLNonNull(GraphQLString)
          }
        },
        resolve: function (root, params) {
          const bookModel = new BookModel(params);
          const newBook = bookModel.save();
          if (!newBook) {
            throw new Error('Error');
          }
          return newBook
        }
      },
      updateBook: {
        type: bookType,
        args: {
          id: {
            name: 'id',
            type: new GraphQLNonNull(GraphQLInt)
          },
          isbn: {
            type: new GraphQLNonNull(GraphQLString)
          },
          title: {
            type: new GraphQLNonNull(GraphQLString)
          },
          author: {
            type: new GraphQLNonNull(GraphQLString)
          },
          description: {
            type: new GraphQLNonNull(GraphQLString)
          },
          publishedYear: {
            type: new GraphQLNonNull(GraphQLInt)
          },
          publisher: {
            type: new GraphQLNonNull(GraphQLString)
          }
        },
        resolve(root, params) {
          return BookModel
          .findByPk(params.id)
          .then(book => {
            if (!book) {
              throw new Error('Not found');
            }
            return book
              .update({
                isbn: params.isbn || book.isbn,
                title: params.title || book.title,
                author: params.author || book.author,
                description: params.description || book.description,
                publishedYear: params.publishedYear || book.publishedYear,
                publisher: params.publisher || book.publisher,
              })
              .then(() => { return book; })
              .catch((error) => { throw new Error(error); });
          })
          .catch((error) => { throw new Error(error); });
        }
      },
      removeBook: {
        type: bookType,
        args: {
          id: {
            type: new GraphQLNonNull(GraphQLInt)
          }
        },
        resolve(root, params) {
          return BookModel
          .findByPk(params.id)
          .then(book => {
            if (!book) {
              throw new Error('Not found');
            }
            return book
              .destroy()
              .then(() => { return book; })
              .catch((error) => { throw new Error(error); });
          })
          .catch((error) => { throw new Error(error); });
        }
      }
    }
  }
});

Finally, add this mutation to the GraphQL Schema exports like below.

module.exports = new GraphQLSchema({query: queryType, mutation: mutation});

7. Test GraphQL using GraphiQL

To test the queries and mutations of CRUD operations, re-run again the Express.js app then open the browser. Go to this address [http://localhost:3000/graphql](http://localhost:3000/graphql "http://localhost:3000/graphql") to open the GraphiQL User Interface.

To get the list of books, replace all of the text on the left pane with this GraphQL query then click the Play button.

To get a single book by ID, use this GraphQL query.

{
  book(id: 1) {
    id
    isbn
    title
    author
    description
    publishedYear
    publisher
    updatedAt
  }
}

To add a book, use this GraphQL mutation.

mutation {
  addBook(
    isbn: "12345678",
    title: "Whatever this Book Title",
    author: "Mr. Bean",
    description: "The short explanation of this Book",
    publisher: "Djamware Press",
    publishedYear: 2019
  ) {
    updatedAt
  }
}

You will the response at the right pane like this.

{
  "data": {
    "addBook": {
      "updatedAt": "2019-02-26T13:55:39.160Z"
    }
  }
}

To update a book, use this GraphQL mutation.

mutation {
  updateBook(
    id: 1,
    isbn: "12345678221",
    title: "The Learning Curve of GraphQL",
    author: "Didin J.",
    description: "The short explanation of this Book",
    publisher: "Djamware Press",
    publishedYear: 2019
  ) {
    id,
    updatedAt
  }
}

You will see the response in the right pane like this.

{
  "data": {
    "updateBook": {
      "id": 1,
      "updated_date": "2019-02-26T13:58:35.811Z"
    }
  }
}

To delete a book by ID, use this GraphQL mutation.

mutation {
  removeBook(id: 1) {
    id
  }
}

You will see the response in the right pane like this.

{
  "data": {
    "removeBook": {
      "id": 1
    }
  }
}

8. Create Vue 2 Application

To install Vue-CLI type this command from the Terminal or Node command line.

sudo npm install -g @vue/cli

or

yarn global add @vue/cli

Next, check the version to make sure that you have the 3.x version of Vue-CLI.

vue --version
3.7.0

Next, create a new Vue.js project by type this command.

vue create client

For now, use the default for every question that shows up in the Terminal. Next, go to the newly created folder.

cd ./client

To make sure that created Vue.js project working, type this command to run the Vue.js application.

npm run serve

or

yarn serve

You will see this page when open [http://localhost:8080/](http://localhost:8080/ "http://localhost:8080/") in the browser.

9. Install/Configure the Required Modules, Dependencies, and Router

Now, we have to install and configure all of the required modules and dependencies. Type this command to install the modules.

npm install apollo-boost vue-apollo graphql-tag graphql vue-router --save

Next, open and edit src/main.js then add these imports.

import ApolloClient from "apollo-boost";
import VueApollo from "vue-apollo";

Add these constant variables then register VueApollo in Vue 2 app.

const apolloClient = new ApolloClient({
  uri: 'http://localhost:3000/graphql'
});

const apolloProvider = new VueApollo({
  defaultClient: apolloClient
});

Vue.use(VueApollo);

new Vue({
  apolloProvider,
  render: h => h(App)
}).$mount('#app')

To register or create routes for the whole application navigation, create a router folder and index.js file.

mkdir src/router
touch src/router/index.js

Open and edit src/router/index.js then add these imports.

import VueRouter from 'vue-router'
import BookList from '@/components/BookList'
import ShowBook from '@/components/ShowBook'
import AddBook from '@/components/AddBook'
import EditBook from '@/components/EditBook'

Add the router to each component or page.

export default new VueRouter({
  routes: [
    {
      path: '/',
      name: 'BookList',
      component: BookList
    },
    {
      path: '/show-book/:id',
      name: 'ShowBook',
      component: ShowBook
    },
    {
      path: '/add-book',
      name: 'AddBook',
      component: AddBook
    },
    {
      path: '/edit-book/:id',
      name: 'EditBook',
      component: EditBook
    }
  ]
})

Add Vue files for above-registered components or pages.

touch src/components/BookList.vue
touch src/components/ShowBook.vue
touch src/components/AddBook.vue
touch src/components/EditBook.vue

Finally, add or register this router file to src/main.js by adding these imports.

import VueRouter from 'vue-router'
import router from './router'

Register the Vue-Router after Vue.config.

Vue.use(VueRouter)

Modify new Vue to be like this.

new Vue({
  apolloProvider,
  router,
  render: h => h(App)
}).$mount('#app')

10. Create a Component to Display List of Books

Before create or show data to the views, we have to add Bootstrap-Vue. Type this command to install the module.

npm i bootstrap-vue

Next, open and edit src/main.js then add these imports.

import BootstrapVue from 'bootstrap-vue'
import 'bootstrap/dist/css/bootstrap.css'
import 'bootstrap-vue/dist/bootstrap-vue.css'

Add this line after Vue.config.

Vue.use(BootstrapVue);

Now, open and edit src/components/BookList.vue then add this template tags that contain a bootstrap-vue table.

<template>
  <b-row>
    <b-col cols="12">
      <h2>
        Book List
        <b-link href="#/add-Book">(Add Book)</b-link>
      </h2>
      <b-table striped hover :items="books" :fields="fields">
        <template slot="actions" scope="row">
          <b-btn size="sm" @click.stop="details(row.item)">Details</b-btn>
        </template>
      </b-table>
    </b-col>
  </b-row>
</template>

Next, add the script tag for hold all Vue 2 codes.

<script></script>

Inside the script tag, add these imports.

import gql from "graphql-tag";
import router from "../router";

Declare the constant variables for GraphQL query.

const GET_BOOKS = gql`
  {
    books {
      id
      title
      author
    }
  }
`;

Add the main Vue 2 export that contains Vue-Apollo calls that filled Vue 2 data.

export default {
  name: "BookList",
  apollo: {
    books: {
      query: GET_BOOKS,
      pollInterval: 300
    }
  },
  data() {
    return {
      fields: {
        title: { label: "Title", sortable: true, class: "text-left" },
        author: { label: "Author", sortable: true, class: "text-left" },
        actions: { label: "Action", class: "text-center" }
      },
      books: []
    };
  },
  methods: {
    details(book) {
      router.push({ name: "ShowBook", params: { id: book.id } });
    }
  }
};

Finally, add the style tag for styling the template.

<style>
.table {
  width: 96%;
  margin: 0 auto;
}
</style>

11. Create a Component to Show and Delete Books

To show the book details that contains all book detail, edit and delete buttons, open and edit src/components/ShowBook.vue then add these template tags that contain a bootstrap-vue component for display the details.

<template>
  <b-row>
    <b-col cols="12">
      <h2>
        Book List
        <b-link href="#/">(Book List)</b-link>
      </h2>
      <b-jumbotron>
        <template slot="header">{{book.title}}</template>
        <template slot="lead">
          ISBN: {{book.isbn}}
          <br>
          Author: {{book.author}}
          <br>
          Description: {{book.description}}
          <br>
          Published Year: {{book.publishedYear}}
          <br>
          Publisher: {{book.publisher}}
          <br>
          Update At: {{book.updatedAt}}
          <br>
        </template>
        <hr class="my-4">
        <b-btn class="edit-btn" variant="success" @click.stop="editBook(book.id)">Edit</b-btn>
        <b-btn variant="danger" @click.stop="deleteBook(book.id)">Delete</b-btn>
      </b-jumbotron>
    </b-col>
  </b-row>
</template>

Next, add the script tag.

<script></script>

Inside the script tag, add these imports.

import gql from "graphql-tag";
import router from "../router";

Declare the constant variables that handle get a single book and delete book queries.

const GET_BOOK = gql`
  query book($bookId: Int) {
    book(id: $bookId) {
      id
      isbn
      title
      author
      description
      publishedYear
      publisher
      updatedAt
    }
  }
`;

const DELETE_BOOK = gql`
  mutation removeBook($id: Int!) {
    removeBook(id: $id) {
      id
    }
  }
`;

Inside main Vue export, add all required functions, variables, and Vue-Apollo function.

export default {
  name: "ShowBook",
  data() {
    return {
      book: '',
      bookId: parseInt(this.$route.params.id)
    };
  },
  apollo: {
    book: {
      query: GET_BOOK,
      pollInterval: 300,
      variables() {
        return {
          bookId: this.bookId
        };
      }
    }
  },
  methods: {
    editBook(id) {
      router.push({
        name: "EditBook",
        params: { id: id }
      });
    },
    deleteBook(id) {
      this.$apollo
        .mutate({
          mutation: DELETE_BOOK,
          variables: {
            id: id
          }
        })
        .then(data => {
          console.log(data);
        })
        .catch(error => {
          console.error(error);
        });
    }
  }
};

Finally, add the style tags to give the view some styles.

<style>
.jumbotron {
  padding: 2rem;
}
.edit-btn {
  margin-right: 20px;
  width: 70px;
}
</style>

12. Create a Component to Add a New Book

To add a new book, open and edit src/components/AddBook.vue then add this Vue 2 template tag that contains a bootstrap-vue form.

<template>
  <b-row>
    <b-col cols="12">
      <h2>
        Add Book
        <b-link href="#/">(Book List)</b-link>
      </h2>
      <b-jumbotron>
        <b-form @submit="onSubmit">
          <b-form-group
            id="fieldsetHorizontal"
            horizontal
            :label-cols="4"
            breakpoint="md"
            label="Enter ISBN"
          >
            <b-form-input id="isbn" v-model.trim="book.isbn"></b-form-input>
          </b-form-group>
          <b-form-group
            id="fieldsetHorizontal"
            horizontal
            :label-cols="4"
            breakpoint="md"
            label="Enter Title"
          >
            <b-form-input id="title" v-model.trim="book.title"></b-form-input>
          </b-form-group>
          <b-form-group
            id="fieldsetHorizontal"
            horizontal
            :label-cols="4"
            breakpoint="md"
            label="Enter Author"
          >
            <b-form-input id="author" v-model.trim="book.author"></b-form-input>
          </b-form-group>
          <b-form-group
            id="fieldsetHorizontal"
            horizontal
            :label-cols="4"
            breakpoint="md"
            label="Enter Description"
          >
            <b-form-textarea
              id="description"
              v-model="book.description"
              placeholder="Enter something"
              :rows="2"
              :max-rows="6"
            >{{book.description}}</b-form-textarea>
          </b-form-group>
          <b-form-group
            id="fieldsetHorizontal"
            horizontal
            :label-cols="4"
            breakpoint="md"
            label="Enter Publisher"
          >
            <b-form-input id="publisher" v-model.trim="book.publisher"></b-form-input>
          </b-form-group>
          <b-form-group
            id="fieldsetHorizontal"
            horizontal
            :label-cols="4"
            breakpoint="md"
            label="Enter Published Year"
          >
            <b-form-input type="number" id="publishedYear" v-model.trim="book.publishedYear"></b-form-input>
          </b-form-group>
          <b-button type="submit" variant="primary">Save</b-button>
        </b-form>
      </b-jumbotron>
    </b-col>
  </b-row>
</template>

Next, add the script tag.

<script></script>

Inside the script, tag adds Vue 2 codes that contain Vue-Apollo GraphQL mutation to save a new book.

import gql from "graphql-tag";
import router from "../router";

const ADD_BOOK = gql`
  mutation AddBook(
    $isbn: String!
    $title: String!
    $author: String!
    $description: String!
    $publisher: String!
    $publishedYear: Int!
  ) {
    addBook(
      isbn: $isbn
      title: $title
      author: $author
      description: $description
      publisher: $publisher
      publishedYear: $publishedYear
    ) {
      id
    }
  }
`;

export default {
  name: "AddBook",
  data() {
    return {
      book: {}
    };
  },
  methods: {
    onSubmit(evt) {
      evt.preventDefault();

      this.$apollo
        .mutate({
          mutation: ADD_BOOK,
          variables: {
            isbn: this.book.isbn,
            title: this.book.title,
            author: this.book.author,
            description: this.book.description,
            publisher: this.book.publisher,
            publishedYear: parseInt(this.book.publishedYear)
          }
        })
        .then(data => {
          console.log(data);
          router.push({ name: "BookList" });
        })
        .catch(error => {
          console.error(error);
        });
    }
  }
};

Finally, give the view a style by adding the style tag.

<style>
.jumbotron {
  padding: 2rem;
}
</style>

13. Create a Component to Edit a Book

To edit a book after getting single book data, open and edit src/components/EditBook.vue then add this Vue 2 template that contains a bootstrap-vue form.

<template>
  <b-row>
    <b-col cols="12">
      <h2>
        Edit Book
        <router-link :to="{ name: 'ShowBook', params: { id: bookId } }">(Show Book)</router-link>
      </h2>
      <b-jumbotron>
        <b-form @submit="onSubmit">
          <b-form-group
            id="fieldsetHorizontal"
            horizontal
            :label-cols="4"
            breakpoint="md"
            label="Enter ISBN"
          >
            <b-form-input id="isbn" v-model.trim="book.isbn"></b-form-input>
          </b-form-group>
          <b-form-group
            id="fieldsetHorizontal"
            horizontal
            :label-cols="4"
            breakpoint="md"
            label="Enter Title"
          >
            <b-form-input id="title" v-model.trim="book.title"></b-form-input>
          </b-form-group>
          <b-form-group
            id="fieldsetHorizontal"
            horizontal
            :label-cols="4"
            breakpoint="md"
            label="Enter Author"
          >
            <b-form-input id="author" v-model.trim="book.author"></b-form-input>
          </b-form-group>
          <b-form-group
            id="fieldsetHorizontal"
            horizontal
            :label-cols="4"
            breakpoint="md"
            label="Enter Description"
          >
            <b-form-textarea
              id="description"
              v-model="book.description"
              placeholder="Enter something"
              :rows="2"
              :max-rows="6"
            >{{book.description}}</b-form-textarea>
          </b-form-group>
          <b-form-group
            id="fieldsetHorizontal"
            horizontal
            :label-cols="4"
            breakpoint="md"
            label="Enter Publisher"
          >
            <b-form-input id="publisher" v-model.trim="book.publisher"></b-form-input>
          </b-form-group>
          <b-form-group
            id="fieldsetHorizontal"
            horizontal
            :label-cols="4"
            breakpoint="md"
            label="Enter Published Year"
          >
            <b-form-input type="number" id="publishedYear" v-model.trim="book.publishedYear"></b-form-input>
          </b-form-group>
          <b-button type="submit" variant="primary">Update</b-button>
        </b-form>
      </b-jumbotron>
    </b-col>
  </b-row>
</template>

Next, add the script tag that contains all required Vue 2 codes with get data and update function.

<script>
import gql from "graphql-tag";
import router from "../router";

const GET_BOOK = gql`
  query book($bookId: Int) {
    book(id: $bookId) {
      id
      isbn
      title
      author
      description
      publishedYear
      publisher
    }
  }
`;

const UPDATE_BOOK = gql`
  mutation updateBook(
    $id: Int!
    $isbn: String!
    $title: String!
    $author: String!
    $description: String!
    $publisher: String!
    $publishedYear: Int!
  ) {
    updateBook(
      id: $id
      isbn: $isbn
      title: $title
      author: $author
      description: $description
      publisher: $publisher
      publishedYear: $publishedYear
    ) {
      updatedAt
    }
  }
`;

export default {
  name: "EditBook",
  data() {
    return {
      bookId: this.$route.params.id,
      book: {}
    };
  },
  apollo: {
    book: {
      query: GET_BOOK,
      variables() {
        return {
          bookId: this.bookId
        };
      }
    }
  },
  methods: {
    onSubmit(evt) {
      evt.preventDefault();

      this.$apollo
        .mutate({
          mutation: UPDATE_BOOK,
          variables: {
            id: parseInt(this.book.id),
            isbn: this.book.isbn,
            title: this.book.title,
            author: this.book.author,
            description: this.book.description,
            publisher: this.book.publisher,
            publishedYear: parseInt(this.book.publishedYear)
          }
        })
        .then(data => {
          console.log(data);
          router.push({
            name: "ShowBook",
            params: { id: this.$route.params.id }
          });
        })
        .catch(error => {
          console.error(error);
        });
    }
  }
};
</script>

Finally, give the view some style by adding the style tag.

<style>
.jumbotron {
  padding: 2rem;
}
</style>

14. Run and Test GraphQL CRUD from the Vue 2 Application

We assume the PostgreSQL server already running, so you just can run Node/Express.js application and Vue 2 app in the separate terminal tabs.

nodemon
cd client
npm run serve

Next, open the browser then go to this address localhost:8080 and you should see these pages.

That it's, the Node, Express, PostgreSQL, Vue 2 and Graphql CRUD Web App. You can find the full source code on our GitHub.