CodeIgniter 4 Rest Api Example Tutorial

CodeIgniter 4 is the latest version of the popular PHP framework CodeIgniter. It is a powerful tool for creating web applications and APIs. In this tutorial, we will create a simple REST API using CodeIgniter 4.

We will create a simple API that will allow users to register, login, and retrieve user information. We will also use the CodeIgniter 4 authentication library to secure our API.

1. Setting Up the Project

First, we need to set up our project. We will use Composer to install CodeIgniter 4.

Run the following command in your terminal to install CodeIgniter 4:

composer create-project codeigniter4/appstarter

This will create a new project in the current directory.

2. Configuring the Database

Next, we need to configure the database. Open the file `app/Config/Database.php` and enter your database credentials.

3. Creating the Model

Now, we need to create the model for our API. Create a new file `app/Models/UserModel.php` and add the following code:

‘required|min_length[3]’, ’email’ => ‘required|valid_email|is_unique[users.email]’, ‘password’ => ‘required|min_length[8]’ ]; if (! $this->validate($rules)) { // Return error response return $this->fail($this->validator->getErrors()); } // Create user $userModel = new UserModel(); $userModel->save([ ‘name’ => $this->request->getVar(‘name’), ’email’ => $this->request->getVar(’email’), ‘password’ => $this->request->getVar(‘password’) ]); // Return success response return $this->respond([ ‘message’ => ‘User created successfully’ ]); } }

This controller will handle the registration of new users.

5. Creating the Authentication Library

Next, we need to create the authentication library for our API. Create a new file `app/Libraries/Auth.php` and add the following code:

db =& $db; } public function login($email, $password) { // Validate the request data $rules = [ ’email’ => ‘required|valid_email’, ‘password’ => ‘required|min_length[8]’ ]; if (! $this->validate($rules)) { // Return error response return $this->fail($this->validator->getErrors()); } // Check if user exists $user = $this->db->table(‘users’)->where(’email’, $email)->get()->getRow(); if (! $user) { // Return error response return $this->fail(‘User not found’); } // Validate password if (! password_verify($password, $user->password)) { // Return error response return $this->fail(‘Invalid password’); } // Return success response return $this->respond([ ‘message’ => ‘User logged in successfully’, ‘user’ => $user ]); } }

This library will handle the authentication of users.

6. Configuring the Routes

Finally, we need to configure the routes for our API. Open the file `app/Config/Routes.php` and add the following code:

$routes->group(‘api’, function($routes) { $routes->post(‘register’, ‘Api::register’); $routes->post(‘login’, ‘Api::login’); });

This will create two routes for our API: one for registering users and one for logging in users.

7. Testing the API

Now, we can test our API. Open a terminal and run the following command to start the development server:

php spark serve

Now, you can make requests to the API using a tool like Postman.

Conclusion

In this tutorial, we have created a simple REST API using CodeIgniter 4. We have also used the authentication library to secure our API.

I hope this tutorial has been helpful. If you have any questions or comments, please let me know in the comments below.

In this Codeigniter 4 rest API example tutorial, you will learn how to create rest API in PHP codeigniter 4 frameworks.

If you want to exchange data between apps and servers. So at that time, you need to rest APIs for exchange data between server and apps.

So this Codeigniter rest API example tutorial will help you to create rest API in Codeigniter 4 framework. And how to create, read, update, and delete data from database table using these APIs.

Before creating a rest API and use it in codeigniter. You can see the architecture of the RESTful API:

How to Create REST ful APIs in CodeIgniter 4

By using the following steps, you can create rest API in CodeIgniter 4 framework:

Step 1: Setup Database and Table
Step 2: Setup Codeigniter Project
Step 3: Basic Configurations
Step 4: Setup Database Credentials
Step 5: Create Model
Step 6: Create Controller
Step 7: Start Development server

Step 1: Setup Database and Table

First of all, start your local server and start phpmyadin.

Then use the following command to create a database:

After that, select your database and run the following sql query to create a Product table into your database:

CREATE TABLE product(
product_id INT(11) PRIMARY KEY AUTO_INCREMENT,
product_name VARCHAR(200),
product_price DOUBLE
)ENGINE=INNODB;

Next, run the following query to insert some data into product table:

INSERT INTO product(product_name,product_price) VALUES
('Product 1','2000'),
('Product 2','5000'),
('Product 3','4000'),
('Product 4','6000'),
('Product 5','7000');

Step 2: Setup Codeigniter Project

In this step, we will download the latest version of Codeigniter 4, Go to this link https://codeigniter.com/download Download Codeigniter 4 fresh new setup and unzip the setup in your local system xampp/htdocs/ . And change the download folder name “demo”

Step 3: Basic Configurations

Next, we will set some basic configuration on the app/config/app.php file, so let’s go to application/config/config.php and open this file on text editor.

Set Base URL like this

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

Step 4: Setup Database Credentials

In this step, we need to connect our project to the database. we need to go app/Config/Database.php and open database.php file in text editor. After opening the file in a text editor, We need to set up database credentials in this file like below.

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

Step 5: Create Model

So go to app/Models/ and create here one model. And you need to create one model name ProductModel.php and update the following code into your ProductModel.php file:

<?php namespace App\Models;
 
use CodeIgniter\Model;
 
class ProductModel extends Model
{
    protected $table = 'product';
    protected $primaryKey = 'product_id';
    protected $allowedFields = ['product_name','product_price'];
}

Step 6: Create Controller

Now, Navigate app/Controllers and create a controller name Products.php. Then update the following method into Products.php controller file:

<?php namespace App\Controllers;
 
use CodeIgniter\RESTful\ResourceController;
use CodeIgniter\API\ResponseTrait;
use App\Models\ProductModel;
 
class Products extends ResourceController
{
    use ResponseTrait;
    // get all product
    public function index()
    {
        $model = new ProductModel();
        $data = $model->findAll();
        return $this->respond($data);
    }
 
    // get single product
    public function show($id = null)
    {
        $model = new ProductModel();
        $data = $model->getWhere(['product_id' => $id])->getResult();
        if($data){
            return $this->respond($data);
        }else{
            return $this->failNotFound('No Data Found with id '.$id);
        }
    }
 
    // create a product
    public function create()
    {
        $model = new ProductModel();
        $data = [
            'product_name' => $this->request->getVar('product_name'),
            'product_price' => $this->request->getVar('product_price')
        ];
        $model->insert($data);
        $response = [
            'status'   => 201,
            'error'    => null,
            'messages' => [
                'success' => 'Data Saved'
            ]
        ];
        return $this->respondCreated($response);
    }
 
    // update product
    public function update($id = null)
    {
        $model = new ProductModel();
        $input = $this->request->getRawInput();
        $data = [
            'product_name' => $input['product_name'],
            'product_price' => $input['product_price']
        ];
        $model->update($id, $data);
        $response = [
            'status'   => 200,
            'error'    => null,
            'messages' => [
                'success' => 'Data Updated'
            ]
        ];
        return $this->respond($response);
    }
 
    // delete product
    public function delete($id = null)
    {
        $model = new ProductModel();
        $data = $model->find($id);
        if($data){
            $model->delete($id);
            $response = [
                'status'   => 200,
                'error'    => null,
                'messages' => [
                    'success' => 'Data Deleted'
                ]
            ];
            return $this->respondDeleted($response);
        }else{
            return $this->failNotFound('No Data Found with id '.$id);
        }
         
    }
 
}

In the above controller method works as follow:

Index() – This is used to fetch all product.
create() – This method is used to insert product info into DB table.
update() – This is used to validate the form data server-side and update it into the MySQL database.
show() – This method is used to fetch single product info into DB table.
delete() – This method is used to delete data from the MySQL database.

Now Navigate to App/Configuration folder. And Open the file “Routes.php”, then find the following code: