In this tutorial, we will implement the steps to integrate MongoDB with CodeIgniter 4 and perform basic CRUD operations.

Step 1: Set Up CodeIgniter 4

If you haven’t already set up CodeIgniter 4, you can create a new project with Composer:

composer create-project codeigniter4/ci4mongodb

OR

Create ci4mongodb in your XAMPP’s htdocs folder and navigate to the project directory:

Step 2: Install MongoDB PHP Driver

To connect MongoDB with CodeIgniter, you need to install the MongoDB PHP driver. Run the following command using Composer:

composer require mongodb/mongodb

Step 3: Configure MongoDB Connection

Create a library class to manage the MongoDB connection. In CodeIgniter 4, database connections are typically defined in the configuration files, but for MongoDB, we will create a custom connection file.

Create a new file: app/Library/MongoDbConnection.php

namespace App/Libraries;

use MongoDB/Client;

class MongoDbConnection {

    protected $client;
    protected $db;

    public function __construct() {
        // Connect to MongoDB
        $this->client = new Client("mongodb://localhost:27017");

        // Select the database
        $this->db = $this->client->selectDatabase('ci4mongo_db');
    }

    public function getCollection($collection)  {
        return $this->db->selectCollection($collection);
    }

}

This class will manage the connection to MongoDB. It uses the MongoDBClient class provided by the MongoDB PHP driver.

Note: Please replace the (/) with a backward slash for the following code.

namespace App/Libraries;
use MongoDB/Client;

Step 4: Create a Model for CRUD Operations

Now that we have the MongoDB connection, let’s create a model to handle CRUD operations.

Create a file app/Models/login/LoginModel.php:

namespace App/Models/login;
use App/Libraries/MongoDbConnection;

class LoginModel {

    protected $collection;

    public function __construct() {
        $mongoDB         = new MongoDbConnection();
        $this->collection  = $mongoDB->getCollection('login_info');
    }

    // Create a new user
    public function createEntry($data) {
        $result = $this->collection->insertOne($data);
        return $result->getInsertedId();
    }

    // Get all users
    public function getEntryList($filter = [], $options = []) {
        return $this->collection->find($filter, $options)->toArray();
    }

    // Get a user by ID
    public function getEntry($filter = [], $options = [])  {
        // return $this->collection->findOne(['_id' => new MongoDBBSONObjectId($id)]);
        return $this->collection->findOne($filter, $options);
    }

    // Update a user by ID
    public function updateEntry($filter, $newData) {
        // return $this->collection->updateOne(
        //     ['_id' => new MongoDBBSONObjectId($id)],
        //     ['$set' => $data]
        // );
        return $this->collection->updateOne($filter, ['$set' => $newData]);
    }

    // Delete a user by ID
    public function deleteEntry($filter) {
        // return $this->collection->deleteOne(['_id' => new MongoDBBSONObjectId($id)]);
        return $this->collection->deleteOne($filter);
    }
}

This model allows you to perform basic CRUD operations: Create, Read, Update, and Delete. It connects to MongoDB through the MongoDbConnection class and performs operations on the specified collection.

Note: Please replace the (/) with a backward slash for the following code.

namespace App/Models/login;
use App/Libraries/MongoDbConnection;

Step 5: Create a Controller for CRUD Operations

Now let’s create a controller to handle the requests.

Create a new file app/Controllers/login/Login.php:

namespace App/Controllers/login;
use App/Controllers/BaseController;
use App/Models/login/LoginModel;

class Login extends BaseController {

    protected $login;

    public function __construct()  {

        $this->login         = new LoginModel();
        $this->loginDefer     = new LoginDeferModel();

        $this->ip_address      = $_SERVER['REMOTE_ADDR'];
        $this->datetime        = date("Y-m-d H:i:s");
    }

    public function delete() {
        $id          = $this->request->getPost('id');
        $where     = [
        '_id'     => new MongoDBBSONObjectId($id),
       ];
        $result = $this->login->deleteEntry($where);
        if($result) {
            $json = [
            'message'   => "<span class='text-success'>Selected login has been deleted successfully.</span>",
                    'status'    => true,
           ];
        } else {
            $json = [
            'message'   => "<span class='text-danger'>Something went wrong. Please try again.</span>",
                    'status'    => false,
              ];
        }
        echo json_encode($json);
    }

}

Note: Please replace the (/) with a backward slash for the following code.

namespace App/Controllers/login;
use App/Controllers/BaseController;
use App/Models/login/LoginModel;

Step 6: Define Routes

You need to define routes to access the CRUD operations. Open app/Config/Routes.php and add the following:

$routes->get('/', 'login/Login::index');

$routes->get('add',       'login/Login::add');
$routes->get('edit',      'login/Login::edit');
$routes->post('create',    'login/Login::create');
$routes->post('update',    'login/Login::update');
$routes->post('delete',    'login/Login::delete');
$routes->post('datatable',     'login/Login::datatable');

Note: Please replace the (/) with a backward slash for the following code.

Step 7: Create views header.php, footer.php, and template.php for reusable structure.

Create a new file app/View/innperpages/header.php:

<!DOCTYPE html>
<html lang="en">

<head>
    <title><?php echo $content_title; ?></title>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/css/bootstrap.min.css" rel="stylesheet">
    <link href="https://cdn.datatables.net/2.1.7/css/dataTables.dataTables.min.css">
    <link href="https://cdn.datatables.net/buttons/3.1.2/css/buttons.dataTables.min.css">
    <script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/js/bootstrap.bundle.min.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.7.1/jquery.min.js"></script>
    <script src="https://cdn.datatables.net/2.1.7/js/dataTables.min.js"></script>
    <script type="text/javascript" src="https://cdn.datatables.net/buttons/3.1.2/js/dataTables.buttons.min.js"></script>

</head>

<body>
    <div class="container-fluid p-5 bg-primary text-white text-center">
        <h1><?php echo $content_title; ?></h1>
    </div>
    
    <div class="container mt-5">
        <div class="row">
        <div class="col-sm-3"></div>
        <div class="col-sm-6">
            <div class="result"></div>
        </div>
    </div>
</div>

Create a new file app/View/innperpages/footer.php:

</body>
</html>

Create a new file app/View/innperpages/template.php:

<?php 
echo view('innerpages/header');
echo view($main_content);
echo view('innerpages/footer');

Step 7: Create views to delete the record from MongoDB

Create a new file app/View/login/scripts.php:

<script type="text/javascript">
    $(document).ready(function() {
        
        var table_login = $('#table-login').DataTable({
            "processing": true,
            "serverSide": true,
            "ajax": {
                "url"  : "<?= base_url('datatable') ?>",
                "type" : "POST",
            },
        });

        $("#table-login tbody").on('click', 'button', function() {
            var id = $(this).attr('data-id');
            if(this.name == "btn-delete") {
                var is_delete = confirm("Are your sure?");
                if(is_delete) {
                    $.post('<?php echo base_url("delete") ?>', {id: id}, function(result) {
                    if(result.status) {
                        $(".result").html(result.message);
                            table_login.ajax.reload();
                        } else {
                            $(".result").html(result.message);
                        }
                    }, 'json');
                }
            }
        });
    });
</script>

In this tutorial, we learned how to integrate MongoDB with CodeIgniter 4 and perform basic CRUD delete operations.