Skip to content
Postman API Testing Tips

How To Use Postman With Codeigniter

API Testing Blog

Setting up Your CodeIgniter Project for API Testing

Before you start diving into Postman, ensure your CodeIgniter project is properly configured for API development. Here’s a quick guide:

1. Install the REST Server Library:

2. Configure the Library:

  • Usually, this involves adding the library to your autoload.php file and configuring basic settings like the API version, error handling, etc. Refer to the library’s documentation for specific instructions.

3. Create an API Controller:

  • Create a new controller (e.g., Api_controller.php) within the controllers folder that will handle all your API requests.

4. Define API Endpoints:

  • In your API controller, define methods that represent different API endpoints. For example:
    • get_users()
    • create_user()
    • update_user()
    • delete_user()

5. Implement the Logic:

  • Within each method, write the business logic for processing the API request. This will involve interacting with your database, handling data transformations, and returning responses.

Using Postman for CodeIgniter API Testing

Postman is a powerful tool that simplifies the process of making API requests and analyzing responses. Here’s how to leverage its features for testing your CodeIgniter API:

1. Sending Requests

  • Launch Postman: Open the Postman app or access its web interface.
  • Choose a Method: Select the appropriate HTTP method (GET, POST, PUT, DELETE, etc.) for your API endpoint.
  • Enter the URL: Type in the full URL of your API endpoint. For example: http://localhost/your_project_name/api/users
  • Add Headers: If your API requires authorization or specific headers, set them in the “Headers” tab.
  • Provide Body Data: For methods like POST, PUT, or PATCH, add the necessary data in the “Body” tab. You can choose the appropriate format (form-data, raw JSON, etc.).
  • Send the Request: Click the “Send” button to execute the request.

2. Example: GET Request

CodeIgniter API (users controller):

<?php
defined('BASEPATH') OR exit('No direct script access allowed');


class Users extends CI_Controller {


    public function __construct() {
        parent::__construct();
        $this->load->library('rest_controller');
    }


    public function get_users() {
        $users = $this->db->get('users')->result_array();
        $this->response($users, REST_Controller::HTTP_OK);
    }
}

Postman Request:

  • Method: GET
  • URL: http://localhost/your_project_name/api/users
  • Headers: None (if your API doesn’t need authorization)
  • Body: (None for a GET request)

Response:

  • Postman will display the response in the “Body” tab. It should be a JSON array containing the data of your users.

3. Example: POST Request

CodeIgniter API (users controller):

<?php
defined('BASEPATH') OR exit('No direct script access allowed');


class Users extends CI_Controller {


    public function __construct() {
        parent::__construct();
        $this->load->library('rest_controller');
    }


    public function create_user() {
        $data = $this->input->post();
        $this->db->insert('users', $data);
        $this->response(['message' => 'User created successfully'], REST_Controller::HTTP_CREATED);
    }
}

Postman Request:

  • Method: POST
  • URL: http://localhost/your_project_name/api/users
  • Headers:
    • Content-Type: application/json
  • Body: (JSON)
{
    "name": "John Doe",
    "email": "john.doe@example.com"
}

Response:

  • Postman will display a success message in the “Body” tab. The status code should be 201 (Created).

Advanced Techniques

1. Testing Error Cases

  • Send requests with invalid parameters or missing fields to test the API’s error handling.
  • Analyze the error responses in Postman, verifying that the appropriate error messages and status codes are returned.

2. Using Environment Variables

  • Postman allows you to store environment variables, making it easy to switch between different API environments (development, testing, production).
  • Define the base URL and any API keys or secrets within environment variables for convenient configuration.

3. Running Tests with Collections

  • Create collections in Postman to group related API requests.
  • Implement test scripts to automate verification of responses and assertions.
  • Run your collections repeatedly for regression testing or continuous integration.

Conclusion

Postman is an essential tool for testing CodeIgniter APIs. By using its intuitive interface and powerful features, you can thoroughly test your API’s functionality, error handling, and performance. Follow the steps provided in this guide to enhance your CodeIgniter API development process and ensure the quality of your applications.

API Testing Blog