JWT (Json Web Tokens) can be used for user authentication. They are token-based. First, you need to encode the token and send it to the client. Client will save it in his local storage or cookie. In order to decode the token, user must provide the token. Both encode and decode function on JWT wll be performed on server side in PHP.
Or you can download and include it manually in your PHP project.
Encode JWT in PHP
When admin is logged-in, we need to generate his authentication token. First, you need to include the JWT and Key class on top of your file.
require_once "vendor/autoload.php";
use Firebase\JWT\JWT;
use Firebase\JWT\Key;
Following code will generate a JWT using ID.
$jwt_key = "your_secret_key"; // This should be consistent
$issued_at = time();
// $expiry = strtotime("+30 days");
// jwt valid for 30 days (60 seconds * 60 minutes * 24 hours * 30 days)
$expiry = $issued_at + (60 * 60 * 24 * 30);
$payload = [
'iss' => 'https://your-website.com',
'aud' => 'https://your-website.com',
'iat' => $issued_at, // issued at
'nbf' => $issued_at, // not before
'exp' => $expiry, // expiry time
"id" => 1
];
$jwt = JWT::encode($payload, $jwt_key, 'HS256');
Here, we have set the expiry date of this token to 30 days.
iss: Issuer. It tells who issued this token. Usually it is a URL of the server from where the JWT is being generated.
aud: Audience. This tells who can use this token. By providing the URL of your website, you are telling that this token will be valid if it comes from your website only. You can also pass it as an array if you want to allow multiple audience for same token.
iat: It will be a timestamp in seconds since January 01, 1970 00:00:00 UTC.
nbf: The timestamp seconds after which the token can be used. Token provided before this time will not be accepted. We are setting it same as issued time, so you will be able to use it as soon as you generate it.
exp: This will be the timestamp in seconds when the token will be expired. It will also be timestamps seconds since January 01, 1970 00:00:00 UTC. We are setting it’s validity for 30 days.
id: Optional. This is the custom claim that we are attaching with JWT. So when we decode the token, we will get this ID. This ID can be used to check if the user still exists in the database.
Here we are using HS256 algorithm that is used for authentication in JWT. It is a combination of 2 cryptographic methods:
HMAC (Hash-based Message Authentication Code)
SHA-256 (Secure Hash Algorithm 256 bit)
HMAC
HMAC combines cryptographic hash function with a secret key, in this case it will be $jwt_key. It ensures that the token is not been changed and is sent from the owner of secret key (your server).
SHA-256
SHA-256 generates a 256-bit hash from any given value. It is a one-way encryption method. It means that once the hash is generated, it cannot be decrypted back to its original state. So you will not be able to see the original message once it is encrypted.
So in JWT::encode function call, we are sending our payload and secret key. We are also telling the php-jwt library to use the HS256 algorithm. It takes our payload and encrypt it with our secret key and return the hash.
You do not have to save this token in your database. Just return it as a response to AJAX request and user can save it in his local storage.
localStorage.setItem("accessToken", accessToken)
To save the token on user side, we are using localStorage web API. This will keep the access token in local storage until removed using Javascript localStorage.removeItem(“accessToken”) or if the browsing history is deleted. However, it can store only upto 10 MB. But that will be enough in this case. The token generated will be a string of just a few bytes.
It stores the data in key-value pair. In this case, our key is “accessToken” and our value is the accessToken received from server.
Note: The first parameter is a string and second is a variable.
Decode JWT in PHP
Now whenever admin sends an AJAX request, he needs to pass that access token in headers.
Here, we are first creating an AJAX (Asynchronous JavaScript and XML) object. Then we are opening the request with method POST and the server URL is “index.php”, you can write your own route. Third parameter is async, it’s default value is also true. It means that the request will be processed asyncronously. If you use false, it will not return any value until the response is received, thus blocking the UI which is not good for user experience.
After that, we are attaching Authorization header with the AJAX request. It is a good practice to send authorization tokens in header for security and it is also a standardized way of sending tokens. So if you are developing a website or a mobile application, every developer will know that the token needs to be sent in the header.
We are using Bearer authorization token because they hide the sensitive data that we are sending in payload. Thus, even if someone reads the headers, he won’t be able to read the ID of user. And we are fetching the token value from local storage we saved earlier.
Finally, we are sending the request. If you are to send some data with the request too, you can send it in FormData object. Check our tutorial on how to send AJAX request with FormData.
Then on server side, we need to get the access token from Authorization header and decode it to see if it is valid.
// index.php
// Get the JWT from the Authorization header
try
{
$headers = getallheaders(); // returns an array of all headers attached in this request
if (!isset($headers['Authorization']))
{
echo json_encode([
"status" => "error",
"message" => "'authorization' header not present."
]);
exit();
}
$auth_header = $headers['Authorization'];
list($jwt) = sscanf($auth_header, "Bearer %s");
$decoded = JWT::decode($jwt, new Key($jwt_key, 'HS256'));
$id = $decoded->id;
return $id;
}
catch (\Exception $exp)
{
echo json_encode([
"status" => "error",
"message" => $exp->getMessage()
]);
exit();
}
First, we are fetching all the headers from the request. Then we are checking if the Authorization header is present in the request. If not, then we are throwing an error. So if user fails to attach the Authorization header in the request, it will not process further.
sscanf: This function is used to read and parse the value from a string. While “sprintf” is used to only format the data, but this function reads the data and parses as well.
Our format “Bearer %s” tells the function to expecct Bearer at the start of the string. And %s tells it to put the remaining string in a variable.
list() is a built-in function in PHP. It is used to assign multiple values to multiple variables respectively. In this case, we are assigning value of “%s” to $jwt variable.
After that, we are decoding the token. Decode function in JWT PHP is a little different than the encode function. First parameter is the token, second is an instance of Key class from php-jwt library. It also accepts 2 parameters, first is the secret key used to generate the token and second is the algorithm used while generating the token. If there is any mismatch in token, secret key or algorithm, it will throw an exception and we will receive that in catch block.
It will return the payload that we are saving in $decoded variable. From this decoded variable, you can get the ID of the authenticated user.
That’s how you can encode and decode the JWT in PHP. If you face any problem in following this, kindly do let me know.
Picture Competition is a mobile responsive real-time web application developed in Node JS and Mongo DB. Its frontend is designed in Bootstrap and Vue JS. You can create competition between 2 people and the others can vote on the person based on looks or skills etc.
It uses login authentication using JWT (JsonWebToken). It does not use the browser session due to the following reasons:
Sessions are destroyed once your app is restarted from terminal.
Sessions are not linked with the server, they are stored in browser only.
The benefit of using JWT is that you can always log out a user from your Mongo DB. Just go to the “users” collection and find the specific user. Then empty the “accessToken” field of that user’s document.
Login and Registration
2. Create Competitions
Registered users can create competitions between 2 users. You can enter name and upload 1 picture of each competitor. There is no limit in the number of competitions to create, you can create as many as you want. You can view your created competitions on your “My Competitions” page.
As soon as you create a competition, it will automatically be displayed to all the users as well as to the admin in real-time. Users do not have to refresh the page to see new competitions. It uses Socket IO to display data in real-time.
Create Competition
3. Search
Users can search competitions by the name of competitors. Data is filtered and rendered using Vue JS. There is no need to press the enter key, the data is filtered as soon as the user starts typing in the search box.
Search and Sort
4. Sort
Users can also sort the competitions by any of the following for sorting functions:
Highest votes to lowest.
Lowest votes to highest.
Oldest to newest.
Newest to oldest (default).
5. Vote on Competition
Logged-in users can vote on the competition. You can either vote on one of the competitors. Once the vote is cast on one competitor, it cannot be removed. Also, you can cast your vote on only one of the competitors, not on both of them. It is also real-time, as soon as the vote is cast, it will automatically be displayed to all the users and the counter is incremented. The counter displays the number of votes cast on each competitor.
Votes
6. Delete Competition
Competitions can only be deleted by either of the users who created the competition, or by the admin. Once the competition is deleted, all the uploaded images will be deleted too. As soon as the competition is deleted, it will automatically be removed from all the other users too, without having them refresh the page.
7. Realtime Update using Sockets
Sockets are used for real-time communication. Instead of fetching the data from the server after regular intervals, sockets attach listeners to the client-side. Listeners are listening to the events sent from the server. The server will emit the event and the client will listen to that event and respond accordingly. In this project, sockets are used for the following features:
When competition is created.
When competition is deleted.
To increase the counter after vote is casted to the competition.
Notifications.
8. Notifications
When a competition is deleted by the admin, the admin will write the reason for the deletion. Thus, a notification will be sent to the user along with the reason why his competition was removed. By default, notification status is “unread” and they are highlighted. As soon as the user clicks on any of the notifications, that notification will be marked as “read” and it will no longer be highlighted.
Notifications
9. Load More Button
When the data in the database increases, it is not feasible to load all the data in a single AJAX request. So a “load more” button is created to solve this problem. For example, 10 records are fetched in the first AJAX request. The next 10 records will be fetched when the “load more” button is clicked, and so on.
Load More
10. Admin Panel
Admin panel is created so you (administrator) can delete any competition you find offensive. The default email and password of admin are:
email = admin@gmail.com password = admin
11. Manage Competitions
Admin can delete competitions that he finds offensive. However, the admin must give the reason why that competition is deleted. A notification will be sent to the user who created that competition and he will be able to view it from the top navigation bar.
12. Reset Password
Now you will be able to reset your password if you ever forgot. You just need to enter your email address and an email will be sent to you with a link to reset the password. We are using the nodemailer module to send an email.
Forgot PasswordReset Password
13. Email Verification
When a new user registers, we are sending a verification email to the user’s entered email address. The user will not be able to log in until he verifies his email address. When a user clicks the link on his email address, he will receive a message that says that his account is verified. Then he will be able to log in successfully.
Email Verification
14. SMTP Configurations from Admin Panel
To send an email, you will need an SMTP server. Every SMTP server requires some configurations to set up that include, host, port, email, and password. You can write these values directly hardcoded in your code, but to update these values in the future, you have to find these values in the code and update them.
In this project, you can set these configurations directly from the admin panel. Once the values are set, new emails will be sent using the new configurations.
SMTP configurations from admin panel
15. Adult Image Validation
This is a must-have feature if you are creating a website that allows users to upload pictures and they will be seen to the world. Anyone can upload an image that contains adult content, and it will not be good for your business. So when the user is uploading pictures while creating competition, the system will automatically check if the image is safe to upload.
If the image is an adult image, then an error will be shown to the user and it will not be uploaded.
16. Admin Panel Stats
Admin can see total users, total competitions, and total votes cast so far. They are also real-time, so when a new user is registered, or new competition is created, or event a new vote is cast, it will automatically be incremented here.
Also, when competition is deleted, the number will automatically get decremented as well, without having the admin refresh the page.
Admin Panel Stats
17. Real-time Comments
Users can comment on each competition. And they are also real-time as well. Once a new comment is added, it will immediately be displayed to all the other users as well. They do not have to refresh the page to see new comments.
Real-time Comments
18. User Profile
Users can now update their names and profile pictures. We are using the fs (file system) module to upload the picture. User can also add their bio, date of birth, country, and social media links. Media links include Facebook, Instagram, google plus, Twitter, and LinkedIn.
User can also change their account password. In order to change the password, the user must enter the current password. The new password should be entered twice for confirmation.
User Profile
19. Free Customer Support
This is not a feature of the project, but it is a free service provided for the pro version only. That means if you find any difficulty in installing or configuring the project, we will help you install it. Also, if you encounter any error or a bug in the released version, then it can be fixed too.
These are all the features we have right now in the picture competition web app. We are open to more ideas. If you have more ideas to add, kindly do let us know.
This tutorial will discuss how you can create a JWT authentication system (Login, Registration, and Logout) using JSON Web Token in Node JS and Mongo DB. You can follow the video below if you prefer a video tutorial:
First, make sure you have downloaded and installed Node JS and Mongo DB. You can also download Mongo DB Compass to view the database.
Setup the Project
First, create an empty folder anywhere on your computer and open the command prompt in it. Once CMD is open inside the folder, run the following command:
express: A framework used for better routing, middleware etc.
express-formidable: To get the values from AJAX.
mongodb: To interact with database.
http: To handle HTTP requests.
bcrypt: To encrypt and decrypt the password.
jsonwebtoken: To generate JSON Web Token used for authentication.
ejs: View engine to display HTML pages.
Now, create a file named “server.js” at the root of your folder. To start the server you can use the following command:
node server.js
But every time you made some changes in the server.js file, you have to run that command again. To prevent this, you can install the nodemon module using the following command:
npm install -g nodemon
Then you can use the following command to keep the server running:
nodemon server.js
Start the Server
Open your server.js file and write the following code in it:
// include express module
var express = require("express");
// create instance of express
var app = express();
// use express-formidable middleware
var formidable = require("express-formidable");
app.use(formidable());
// include mongodb module
var mongodb = require("mongodb");
// get mongodb client
var mongoClient = mongodb.MongoClient;
// get ObjectId, it is unique for each document
var ObjectId = mongodb.ObjectId;
// create http server from express instance
var http = require("http").createServer(app);
// include bcrypt module
var bcrypt = require("bcrypt");
// include jsonwebtoken module
var jwt = require("jsonwebtoken");
// random secret string
var accessTokenSecret = "myAccessTokenSecret1234567890";
// use public folder for css and js files
app.use(express.static(__dirname + "public"));
// use ejs engine to render html files
app.set("view engine", "ejs");
var mainURL = "http://localhost:3000";
// start the server at port 3000
http.listen(3000, function () {
console.log("Server started.");
// connect with mongodb
mongoClient.connect("mongodb://localhost:27017", function (error, client) {
// database name will be "jwt_authentication"
var database = client.db("jwt_authentication");
console.log("Database connected");
});
});
This will include all the necessary modules and start the server at port 3000. The module used for JWT authentication is named jsonwebtoken. You can access it from your browser with the following link:
http://localhost:3000/
You will see an error because there isn’t any route for the home page. Open your CMD and you will see 2 messages:
“Server started.”
“Database connected”
If you open the Mongo DB Compass you will not see a database. Because database will be created only there is at least one collection in it. So our database will be created when there is at least one user in our database.
User Registration
Go to the following address in your browser:
http://localhost:3000/signup
First, we are going to create a route in our server.js right after the database is connected.
server.js
// route for signup requests
app.route("/signup")
// get request accessed from browser
.get(function (request, result) {
// render signup.ejs file inside "views" folder
result.render("signup");
});
Now we need to create a folder named views at our root folder. Inside this folder, create a file named signup.ejs (note the extension). Also create 2 more files, header.ejs and footer.ejs.
header.ejs
<!-- menu items will be created using Javascript -->
<ul id="main-menu">
</ul>
<script>
// variables used in all files
var mainURL = "http://localhost:3000";
var accessTokenKey = "accessToken";
var user = null;
</script>
<script>
function doRegister(form) {
// disable the submit button and show "Loading..." text
form.submit.setAttribute("disabled", "disabled");
form.submit.value = "Loading...";
// create AJAX object
var ajax = new XMLHttpRequest();
// 1. method is POST
// 2. path where request will be sent
// 3. request will be asynchronous
ajax.open("POST", mainURL + "/signup", true);
// called everytime status of request changes
ajax.onreadystatechange = function () {
// when response is received from server
if (this.readyState == 4) {
// if the request is OK
if (this.status == 200) {
// response received from server
console.log(this.responseText);
// enable the submit button
form.submit.removeAttribute("disabled");
form.submit.value = "Register";
// convert the JSON string into Javascript object
var response = JSON.parse(this.responseText);
// display message
alert(response.message);
// if the user is created, then redirect to login
if (response.status == "success") {
window.location.href = "/login";
}
}
// if there is an internal server error
if (this.status == 500) {
console.log(this.responseText);
}
}
};
// create form data object from form
var formData = new FormData(form);
// actually sending the AJAX request
ajax.send(formData);
// prevent the form from submitting
return false;
}
</script>
This will show a form with input fields for name, email and password. Now we need to create a POST route in our server.js. We will chain the POST route after our “/signup” GET route.
// route for signup requests
app.route("/signup")
// get request accessed from browser
.get(function (request, result) {
// render signup.ejs file inside "views" folder
result.render("signup");
})
// post request called from AJAX
.post(async function (request, result) {
// get values from signup form
var name = request.fields.name;
var email = request.fields.email;
var password = request.fields.password;
// check if email already exists
var user = await database.collection("users").findOne({
"email": email
});
if (user != null) {
result.json({
"status": "error",
"message": "Email already exists."
});
return true;
}
// encrypt the password
bcrypt.hash(password, 10, async function (error, hash) {
// insert in database
await database.collection("users").insertOne({
"name": name,
"email": email,
"password": hash,
"accessToken": ""
});
// send the response back to client
result.json({
"status": "success",
"message": "Signed up successfully. You can login now."
});
});
});
If you run the code now, you will see a registration form. You can enter your name, email, and password and hit enter. The first time, you will see a success message and you will be redirected to the login route. You can refresh your Mongo DB Compass, and you will see your database and one collection of “users”. Inside this collection, you will see your document inserted. If you enter the same email again, you will get an error.
User Login – JWT authentication
Go to the following address in your browser:
http://localhost:3000/login
First, we are going to create a route in our server.js right after the signup route.
server.js
// route for login requests
app.route("/login")
// get request accessed from browser
.get(function (request, result) {
// render login.ejs file inside "views" folder
result.render("login");
});
Then create a file named login.ejs and write the following code in it:
<script>
function doLogin(form) {
// disable the submit button and show "Loading..." text
form.submit.setAttribute("disabled", "disabled");
form.submit.value = "Loading...";
// create AJAX object
var ajax = new XMLHttpRequest();
// 1. method is POST
// 2. path where request will be sent
// 3. request will be asynchronous
ajax.open("POST", mainURL + "/login", true);
// called everytime status of request changes
ajax.onreadystatechange = function () {
// when response is received from server
if (this.readyState == 4) {
// if the request is OK
if (this.status == 200) {
// response received from server
console.log(this.responseText);
// enable the submit button
form.submit.removeAttribute("disabled");
form.submit.value = "Login";
// convert the JSON string into Javascript object
var response = JSON.parse(this.responseText);
// if user is logged in successfully
if (response.status == "success") {
// get access token from server
var accessToken = response.accessToken;
// save in local storage
localStorage.setItem("accessToken", accessToken);
// redirect to home page
window.location.href = "/";
} else {
// display message
alert(response.message);
}
}
// if there is an internal server error
if (this.status == 500) {
console.log(this.responseText);
}
}
};
// create form data object from form
var formData = new FormData(form);
// actually sending the AJAX request
ajax.send(formData);
// prevent the form from submitting
return false;
}
</script>
This will show a form with input fields for email and password. Now we need to create a POST route in our server.js. We will chain the POST route after our “/login” GET route.
// route for login requests
app.route("/login")
// get request accessed from browser
.get(function (request, result) {
// render login.ejs file inside "views" folder
result.render("login");
})
// post request called from AJAX
.post(async function (request, result) {
// get values from login form
var email = request.fields.email;
var password = request.fields.password;
// check if email exists
var user = await database.collection("users").findOne({
"email": email
});
if (user == null) {
result.json({
"status": "error",
"message": "Email does not exists."
});
return false;
}
// check if password is correct
bcrypt.compare(password, user.password, async function (error, isVerify) {
if (isVerify) {
// generate JWT of user
var accessToken = jwt.sign({
"email": email
}, accessTokenSecret);
// update JWT of user in database
await database.collection("users").findOneAndUpdate({
"email": email
}, {
$set: {
"accessToken": accessToken
}
});
result.json({
"status": "success",
"message": "Login successfully.",
"accessToken": accessToken
});
return false;
}
result.json({
"status": "error",
"message": "Password is not correct."
});
});
});
If you run the code now, you will see a login form. You can enter your email and password and hit enter. If the credentials are correct, then it will save the access token in your local storage in your browser, and you will be redirected to the home page. You can refresh your Mongo DB Compass, and you will see that the accessToken field of the user has been updated. If you enter the wrong credentials, then it will not update the database.
Home Page
Now we need to create a route for our home page in server.js:
// route for home page
app.get("/", function (request, result) {
result.render("index");
});
Create a file named index.ejs inside views folder and write the following code in it:
<%- include ("header") %>
<%- include ("footer") %>
Now comes the footer part. Following will be the code of your footer.ejs file:
footer.ejs
<script>
// get user on page load
window.addEventListener("load", function () {
getUser();
});
function getUser() {
// check if user is logged in
if (localStorage.getItem(accessTokenKey)) {
// call AJAX to get user data
var ajax = new XMLHttpRequest();
ajax.open("POST", mainURL + "/getUser", true);
ajax.onreadystatechange = function () {
if (this.readyState == 4) {
if (this.status == 200) {
// console.log(this.responseText);
var response = JSON.parse(this.responseText);
if (response.status == "success") {
// user is logged in
window.user = response.user;
} else {
// user is logged out
localStorage.removeItem(accessTokenKey);
}
showMainMenu();
}
if (this.status == 500) {
console.log(this.responseText);
}
}
};
var formData = new FormData();
formData.append("accessToken", localStorage.getItem(accessTokenKey));
ajax.send(formData);
return false;
}
showMainMenu();
}
function doLogout() {
// send beacon to server before redirecting
var formData = new FormData();
formData.append("accessToken", localStorage.getItem(accessTokenKey));
navigator.sendBeacon(mainURL + "/logout", formData);
// remove access token from local storage
localStorage.removeItem(accessTokenKey);
return true;
}
function showMainMenu() {
var html = "";
// if user is logged in
if (localStorage.getItem(accessTokenKey)) {
html += `<li>
<a href='/login' onclick='return doLogout();'>Logout</a>
</li>`;
} else {
html += `<li>
<a href='/login'>Login</a>
</li>`;
html += `<li>
<a href='/signup'>Signup</a>
</li>`;
}
// show in main menu
document.getElementById("main-menu").innerHTML = html;
}
</script>
This will show login and signup links if the user is not logged in. If the user is logged in, then it will display a logout button. When the logout button is clicked, it will be redirected to the “/login” route. But before redirecting, it will send a beacon to the server to empty the accessToken field in the database. So we need to create POST routes for “/getUser” and for “/logout”:
// return user data using access token
app.post("/getUser", async function (request, result) {
var accessToken = request.fields.accessToken;
var user = await database.collection("users").findOne({
"accessToken": accessToken
});
if (user == null) {
result.json({
"status": "error",
"message": "User has been logged out. Please login again."
});
return false;
}
result.json({
"status": "success",
"message": "Data has been fetched.",
"user": user
});
});
// empty the access token of user (logout)
app.post("/logout", async function (request, result) {
var accessToken = request.fields.accessToken;
await database.collection("users").findOneAndUpdate({
"accessToken": accessToken
}, {
$set: {
"accessToken": ""
}
});
result.json({
"status": "success",
"message": "User has been logged out."
});
});
With that, your authentication is completed. You can log in and log out now. Once you log out and refresh the Mongo DB Compass, you will see the accessToken field becomes empty. And it will again have the value once the user logged in again.
Why we used Beacon ?
You might have noticed that we have used Beacon instead of AJAX when the logout button is clicked. The reason for this is when the browser navigates from one page to another, the AJAX calls are sometimes aborted by the browser. To prevent this, we use beacons.
Get Data using AJAX
Now that your authentication system is done, you might want to show data to logged-in users only. So for example, you have a blogging website and you want to show your blog posts to logged-in users only. So you need to do the following steps.
1) Create Variable and a Function
In the file where you want to fetch and display the data, create the following variable and a function in Javascript.
<script>
var onPostsPage = true;
function getPosts() {
// call ajax
}
</script>
If you want to learn how to call an AJAX request and show data from it, follow this tutorial.
2) Call Function if Variable is Set
In your footer.ejs, when the user is logged-in, check if this variable is set and is true. If yes, then simply call that function.
// user is logged in
window.user = response.user;
if (typeof onPostsPage !== "undefined" && onPostsPage) {
getPosts();
}
So, that’s how you can create a JWT authentication system In Node JS and Mongo DB.