CodeIgniter 4 Rest Api Example Tutorial

torque-programming 0 Comments how to create REST APIs in PHP CodeIgniter 4 framework, How to Create RESTful API in CodeIgniter 4 8 min read

Codeigniter tutorial, you will learn how to create REST APIs in PHP CodeIgniter 4 framework. REST APIs are used to exchange data between applications and servers. This tutorial will show you how to create, read, update, and delete data from a database table using REST APIs in CodeIgniter 4. Before creating a REST API, it’s important to understand the architecture of a RESTful API. By following the steps outlined in this tutorial, you’ll be able to create a REST API in CodeIgniter 4 and use it to exchange data between your server and applications.

How to Create RESTful API in CodeIgniter 4

How To Create RESTAPI in Codeigniter 4 Framework Torque Programming

Follow the below given steps and create rest API in CodeIgniter 4 framework:

Create Database and Table
Download Codeigniter Latest
Basic Configurations
Setup Database Credentials
Create Model
Create Controller
Start Development server

Step 1: Create Database and Table

Now, we need to create a database for our CodeIgniter 4 application. To do this, we will use PHPMyAdmin, which is a popular web-based database management tool.

To get started, open PHPMyAdmin and create a new database with the name “demo”. You can do this by selecting the “New” button from the left-hand menu and then entering the name “demo” in the appropriate field.

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: Download Codeigniter Project

To get started with CodeIgniter 4, the first step is to download the latest version of the framework. You can download the framework from the official CodeIgniter website at https://codeigniter.com/download.

Once you have downloaded the CodeIgniter 4 setup, unzip the archive and save it in your local system. You can save it in the XAMPP/htdocs/ directory if you are using XAMPP as your local development environment.

Step 3: Basic Configurations

Now, we need to configure some basic settings in the “app/config/app.php” file. To do this, we will open the “config.php” file located in the “application/config” folder using a text editor.

Set Base Url Like This

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

Step 4: Setup Database Credentials

Now, we need to connect our CodeIgniter 4 project to the database. To do this, we will open the “database.php” file located in the “app/Config” folder using a text editor.

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

To create a model in CodeIgniter 4, go to the “app/Models/” directory and create a new file called “ProductModel.php”. Then, add the following code to the “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: