Hi Dev,

This article will give you an example of the Codeigniter 4 login and registration tutorial example. This post will give you a simple example of login and registration in Codeigniter 4. In this article, we will implement a Codeigniter 4 login and registration. I explained simply step by step Codeigniter 4 Authentication Login And Registration Tutorial Example. Alright, let’s dive into the steps.

I will tell you how to create a simple auth system with login and sign-up functionalities. We will specifically use the Codeigniter 4 session to store the state of authenticated users. The login process is done then the user successfully logs into an application.

So let's start to the example.

This is optional; however, if you have not created the codeigniter app, then you may go ahead and execute the below command:

composer create-project codeigniter4/appstarter ci-news

So in this step we will now set the basic configuration on the app/config/app.php file, so let’s implement to application/config/config.php and open this file on the text editor.

public $baseURL = 'http://localhost:8080';
To
public $baseURL = 'http://localhost/example/';

In this third step to generate a database table in your application database.

CREATE TABLE users (
    id INT PRIMARY KEY AUTO_INCREMENT,
    name VARCHAR(150),
    email VARCHAR(150),
    password VARCHAR(150),
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
) ENGINE=INNODB;

In your app/Config/Database.php, and insert database name, username and password into the file.

public $default = [
        'DSN'      => '',
        'hostname' => 'localhost',
        'username' => 'root',
        'password' => '',
        'database' => 'codeigniter_db',
        'DBDriver' => 'MySQLi',
        'DBPrefix' => '',
        'pConnect' => false,
        'DBDebug'  => (ENVIRONMENT !== 'development'),
        'cacheOn'  => false,
        'cacheDir' => '',
        'charset'  => 'utf8',
        'DBCollat' => 'utf8_general_ci',
        'swapPre'  => '',
        'encrypt'  => false,
        'compress' => false,
        'strictOn' => false,
        'failover' => [],
        'port'     => 3306,
    ];

In this step we need to create a user model in your CodeIgniter 4 application.

<?php 
namespace App\Models;  
use CodeIgniter\Model;
 
class UserModel extends Model{

    protected $table = 'users';
    
    protected $allowedFields = [
        'name',
        'email',
        'password',
        'created_at'
    ];
}

<?php 
namespace App\Controllers;  
use CodeIgniter\Controller;
use App\Models\UserModel;
  
class SignupController extends Controller
{
    /**
     * Write code on Method
     *
     * @return response()
     */
    public function index()
    {
        helper(['form']);
        $data = [];
        echo view('signup', $data);
    }
    
    /**
     * Write code on Method
     *
     * @return response()
     */
    public function store()
    {
        helper(['form']);
        $rules = [
            'name'          => 'required|min_length[2]|max_length[50]',
            'email'         => 'required|min_length[4]|max_length[100]|valid_email|is_unique[users.email]',
            'password'      => 'required|min_length[4]|max_length[50]',
            'confirmpassword'  => 'matches[password]'
        ];
          
        if($this->validate($rules)){
            $userModel = new UserModel();

            $data = [
                'name'     => $this->request->getVar('name'),
                'email'    => $this->request->getVar('email'),
                'password' => password_hash($this->request->getVar('password'), PASSWORD_DEFAULT)
            ];

            $userModel->save($data);
            return redirect()->to('/signin');
        }else{
            $data['validation'] = $this->validator;
            echo view('signup', $data);
        }
    }
}

<?php 
namespace App\Controllers;  
use CodeIgniter\Controller;
  
class ProfileController extends Controller
{
    /**
     * Write code on Method
     *
     * @return response()
     */
    public function index()
    {
        $session = session();
        echo "Hello : ".$session->get('name');
    }
}

<?php 
namespace App\Controllers;  
use CodeIgniter\Controller;
use App\Models\UserModel;
  
class SigninController extends Controller
{
    /**
     * Write code on Method
     *
     * @return response()
     */
    public function index()
    {
        helper(['form']);
        echo view('signin');
    } 
    
    /**
     * Write code on Method
     *
     * @return response()
     */
    public function loginAuth()
    {
        $session = session();
        $userModel = new UserModel();
        $email = $this->request->getVar('email');
        $password = $this->request->getVar('password');
        
        $data = $userModel->where('email', $email)->first();
        
        if($data){
            $pass = $data['password'];
            $authenticatePassword = password_verify($password, $pass);
            if($authenticatePassword){
                $ses_data = [
                    'id' => $data['id'],
                    'name' => $data['name'],
                    'email' => $data['email'],
                    'isLoggedIn' => TRUE
                ];

                $session->set($ses_data);
                return redirect()->to('/profile');
            
            }else{
                $session->setFlashdata('msg', 'Password is incorrect.');
                return redirect()->to('/signin');
            }

        }else{
            $session->setFlashdata('msg', 'Email does not exist.');
            return redirect()->to('/signin');
        }
    }
}

Next step we require create a auth view file in your application under directiory;

<!doctype html>
<html lang="en">
<head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title>Codeigniter 4 Authentication Login And Registration Tutorial Example - Mywebtuts.com</title>
    <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.0.2/dist/css/bootstrap.min.css" rel="stylesheet">
</head>
<body>
    <div class="container mt-5">
        <div class="row justify-content-md-center">
            <div class="col-5">
                <h2>Register User</h2>
                <?php if(isset($validation)):?>
                    <div class="alert alert-warning">
                       <?= $validation->listErrors() ?>
                    </div>
                <?php endif;?>
                <form action="<?php echo base_url(); ?>/SignupController/store" method="post">
                    <div class="form-group mb-3">
                        <input type="text" name="name" placeholder="Name" value="<?= set_value('name') ?>" class="form-control" >
                    </div>
                    <div class="form-group mb-3">
                        <input type="email" name="email" placeholder="Email" value="<?= set_value('email') ?>" class="form-control" >
                    </div>
                    <div class="form-group mb-3">
                        <input type="password" name="password" placeholder="Password" class="form-control" >
                    </div>
                    <div class="form-group mb-3">
                        <input type="password" name="confirmpassword" placeholder="Confirm Password" class="form-control" >
                    </div>
                    <div class="d-grid">
                        <button type="submit" class="btn btn-dark">Signup</button>
                    </div>
                </form>
            </div>
        </div>
    </div>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title>Codeigniter 4 Authentication Login And Registration Tutorial Example - Mywebtuts.com</title>
    <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.0.2/dist/css/bootstrap.min.css" rel="stylesheet">
</head>
<body>
    <div class="container">
        <div class="row justify-content-md-center">
            <div class="col-5">
                <h2>Login in</h2>        
                <?php if(session()->getFlashdata('msg')):?>
                    <div class="alert alert-warning">
                       <?= session()->getFlashdata('msg') ?>
                    </div>
                <?php endif;?>
                <form action="<?php echo base_url(); ?>/SigninController/loginAuth" method="post">
                    <div class="form-group mb-3">
                        <input type="email" name="email" placeholder="Email" value="<?= set_value('email') ?>" class="form-control" >
                    </div>
                    <div class="form-group mb-3">
                        <input type="password" name="password" placeholder="Password" class="form-control" >
                    </div>
                    <div class="d-grid">
                         <button type="submit" class="btn btn-success">Signin</button>
                    </div>     
                </form>
            </div>
        </div>
    </div>
</body>
</html>

In the next step, get inside the app/Config/Filters.php, look for $aliases array and replace the whole array with the recommended code.

public $aliases = [
    'csrf'     => \CodeIgniter\Filters\CSRF::class,
    'toolbar'  => \CodeIgniter\Filters\DebugToolbar::class,
    'honeypot' => \CodeIgniter\Filters\Honeypot::class,
    'authGuard' => \App\Filters\AuthGuard::class,
];

<?php 
namespace App\Filters;
use CodeIgniter\HTTP\RequestInterface;
use CodeIgniter\HTTP\ResponseInterface;
use CodeIgniter\Filters\FilterInterface;

class AuthGuard implements FilterInterface
{   
    /**
     * Write code on Method
     *
     * @return response()
     */
    public function before(RequestInterface $request, $arguments = null)
    {
        if (!session()->get('isLoggedIn')){
            return redirect()->to('/signin');
        }
    }
    
    /**
     * Write code on Method
     *
     * @return response()
     */
    public function after(RequestInterface $request, ResponseInterface $response, $arguments = null)
    {
        
    }
}

// custom routes

$routes->get('/', 'SignupController::index');
$routes->get('/signup', 'SignupController::index');
$routes->get('/signin', 'SigninController::index');
$routes->get('/profile', 'ProfileController::index',['filter' => 'authGuard']);

All the required steps have been done, now you have to type the given below command and hit enter to run the Codeigniter app:

php spark serve

Now, Go to your web browser, type the given URL and view the app output:

http://localhost:8080/

Now you can check your own.

I hope it can help you...