Set up JWT authentication with Symfony using the LexikJWTAuthenticationBundle

JSON Web Token (JWT) is an open standard (RFC 7519) that defines a compact and self-contained way for securely transmitting information between parties as a JSON object. This information can be verified and trusted because it is digitally signed. JWTs can be signed using a secret (with the HMAC algorithm) or a public/private key pair using RSA or ECDSA.

Now, let’s proceed with setting up JWT authentication with Symfony using the LexikJWTAuthenticationBundle, you can follow these steps:

1- Install the LexikJWTAuthenticationBundle using Composer:

composer require “lexik/jwt-authentication-bundle”

2- Generate keypairs for encoding JWTs:

php bin/console lexik:jwt:generate-keypair

3- Configure SSL keys and JWT passphrase in your .env file:

###> lexik/jwt-authentication-bundle ###
JWT_SECRET_KEY=%kernel.project_dir%/config/jwt/private.pem
JWT_PUBLIC_KEY=%kernel.project_dir%/config/jwt/public.pem
JWT_PASSPHRASE=<your passphrase here, it can be anything>
###< lexik/jwt-authentication-bundle ###

4- Configure LexikJWTAuthenticationBundle in config/packages/lexik_jwt_authentication.yaml:

lexik_jwt_authentication:
    secret_key: '%env(resolve:JWT_SECRET_KEY)%'
    public_key: '%env(resolve:JWT_PUBLIC_KEY)%'
    pass_phrase: '%env(JWT_PASSPHRASE)%'
    token_ttl: 3600

5- Modify your security configuration in config/packages/security.yaml:

security:
    enable_authenticator_manager: true
    # https://symfony.com/doc/current/security.html#registering-the-user-hashing-passwords
    password_hashers:
        Symfony\Component\Security\Core\User\PasswordAuthenticatedUserInterface: 'auto'
    # https://symfony.com/doc/current/security.html#loading-the-user-the-user-provider
    providers:
        # used to reload user from session & other features (e.g. switch_user)
        app_user_provider:
            entity:
                class: App\Entity\User
                property: username
    firewalls:
       
        main:
            lazy: true
            provider: app_user_provider
            json_login:
                check_path: /api/login_check
                #                username_path: email
                #                password_path: password
                success_handler: lexik_jwt_authentication.handler.authentication_success
                failure_handler: lexik_jwt_authentication.handler.authentication_failure
        api:
            pattern: ^/api/
            stateless: true
            jwt: ~
            # activate different ways to authenticate
            # https://symfony.com/doc/current/security.html#the-firewall

            # https://symfony.com/doc/current/security/impersonating_user.html
            # switch_user: true

    # Easy way to control access for large sections of your site
    # Note: Only the *first* access control that matches will be used
    access_control:
        - { path: ^/api/login, roles: PUBLIC_ACCESS }
        # - { path: ^/admin, roles: ROLE_ADMIN }
        # - { path: ^/profile, roles: ROLE_USER }

6- Define the route for login check in config/routes.yaml:

api_login_check:
    path: /api/login_check

Now, you can authenticate by sending a POST request (using postman) to /api/login_check with the following body:

{
“username”: “test@exemple.com”,
“password”: “123456”
}

The response will contain a JWT token

To authenticate future requests, include the token as a Bearer token in the Authorization header:

Authorization: Bearer <your token here>

That’s it!, by following these steps, you can set up JWT authentication in Symfony using the LexikJWTAuthenticationBundle.