Framework Laravel Package

Getting Started

Minimal Steps to Begin

1. Installation

   • Use Composer to install via:

     composer create-project codeigniter4/appstarter my-project
     

   • Or add to an existing project:

     composer require codeigniter4/framework
     

2. Project Structure

   • Key directories:
     • app/ – Core application logic (Models, Controllers, Views, Libraries).
     • public/ – Web root (entry point: index.php).
     • writable/ – Configs, caches, logs (ensure permissions: chmod -R 775 writable).

3. First Use Case: Hello World

   • Create a controller:

     // app/Controllers/Home.php
     namespace App\Controllers;
     class Home extends BaseController {
         public function index() {
             return view('welcome_message');
         }
     }
     

   • Create a view:

     // app/Views/welcome_message.php
     <h1>Hello, CodeIgniter!</h1>
     

   • Run the server:

     php spark serve
     

   • Visit http://localhost:8080.

4. Configuration

   • Edit app/Config/ files (e.g., App.php, Database.php).
   • Environment variables: .env (copy .env.example first).

5. Routing

   • Define routes in app/Config/Routes.php:

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

Implementation Patterns

Core Workflows

MVC Integration

• Controllers: Extend BaseController; use dependency injection (DI) for services.

  class UserController extends BaseController {
      public function __construct(private UserModel $userModel) {}
  }
  

• Models: Extend BaseModel for database interactions.

  class UserModel extends BaseModel {
      protected $table = 'users';
      protected $allowedFields = ['name', 'email'];
  }
  

• Views: Use view() helper or BaseController's render() method.

  return view('user/profile', ['user' => $user]);
  

Dependency Injection (DI)

• Register services in app/Config/Services.php:

  services => [
      'auth' => \App\Services\AuthService::class,
  ],
  

• Inject into controllers:

  public function __construct(private AuthService $auth) {}
  

Database Operations

• Query Builder:

  $users = $db->table('users')->where('active', 1)->get();
  

• Migrations:

  php spark migrate
  

  Define migrations in app/Database/Migrations/.

Validation

• Use Validation library:

  $rules = [
      'email' => 'required|valid_email',
      'password' => 'required|min_length[8]',
  ];
  $validation = \Config\Services::validation();
  if (!$validation->run($rules, $data)) {
      throw \CodeIgniter\Exceptions\PageNotFoundException::forPageNotFound();
  }
  

API Development

• Use JSONResponse for APIs:

  return $this->response->setJSON([
      'status' => 'success',
      'data' => $users,
  ]);
  

• Leverage Filter for API input sanitization.

Caching

• Enable caching in app/Config/Cache.php.
• Use Cache service:

  $cache = \Config\Services::cache();
  $data = $cache->get('key');
  $cache->save('key', $data, 60);
  

Events and Filters

• Events: Dispatch and listen in app/Config/Events.php.

  Events::on('preSystemShutdown', function () {
      log_message('info', 'System shutting down...');
  });
  

• Filters: Use before/after hooks in controllers or globally in app/Config/Filters.php.

Integration Tips

Third-Party Libraries

• Load libraries in app/Config/Services.php:

  'library' => [
      'parser' => \CodeIgniter\Parser\Parser::class,
      'session' => \CodeIgniter\Session\Session::class,
  ],
  

• Use Services facade:

  $session = service('session');
  

CLI Tasks

• Create custom CLI commands by extending BaseCommand:

  // app/Commands/Example.php
  namespace App\Commands;
  use CodeIgniter\CLI\BaseCommand;
  
  class Example extends BaseCommand {
      public $group = 'custom';
      public $name = 'example';
      protected $description = 'Example command';
  
      public function run() {
          $this->output->writeln('Hello from CLI!');
      }
  }
  

• Register in app/Config/Commands.php and run:

  php spark example
  

Testing

• Use phpunit (included):

  composer test
  

• Write tests in tests/ directory:

  // tests/Unit/HomeTest.php
  public function testIndex() {
      $response = $this->get('/');
      $response->assertOK();
  }
  

Security

• Use Security helper for XSS/CSRF protection:

  echo esc($userInput); // Escape output
  csrf_token(); // In forms
  

• Configure in app/Config/Security.php.

Gotchas and Tips

Pitfalls

1. Case Sensitivity

   • File/namespace paths are case-sensitive on Linux/macOS. Stick to lowercase for consistency.

2. Autoloading Issues

   • Ensure composer dump-autoload runs after adding new classes.
   • Verify autoload.psr-4 in composer.json includes app/.

3. Database Transactions

   • Use db->transStart()/transComplete() for multi-query transactions:

     $db->transStart();
     try {
         $db->table('users')->insert($data);
         $db->table('logs')->insert(['user_id' => $userId]);
         $db->transComplete();
     } catch (\Exception $e) {
         $db->transRollback();
     }
     

4. Session Handling

   • Sessions require session driver in app/Config/Sessions.php.
   • Ensure writable/sessions is writable (chmod 775).

5. Route Caching

   • Cache routes for performance but clear cache after changes:

     php spark route:clear
     

6. Model Relationships

   • Use hasMany, belongsTo, etc., but ensure foreign keys match:

     protected $hasMany = ['posts' => PostModel::class];
     

7. File Uploads

   • Validate file types/sizes in app/Config/Validation.php:

     'upload' => 'uploaded[file]|max_size[file,1024]|mime_in[file,image/jpg,image/png]',
     

8. Environment Switching

   • Use .env for environment-specific configs (e.g., APP_ENV=development).
   • Avoid hardcoding paths; use rootPath(), baseURL().

Debugging Tips

1. Error Logging

   • Check writable/logs/ for errors.
   • Enable debug mode in app/Config/App.php:

     debugToolbar => env('CI_DEBUG_TOOLBAR', true),
     

2. Debug Toolbar

   • Install codeigniter4-debugbar for a PHP Debug Bar:

     composer require --dev peridot-php/codeigniter4-debugbar
     

3. Var Dumping

   • Use var_dump() or dd() (from Debug helper):

     dd($variable); // Dump and die
     

4. Query Logging

   • Enable in app/Config/Database.php:

     'debug' => env('CI_DEBUG_DATABASE', true),
     

5. Route Debugging

   • List all routes:

     php spark route:list
     

Extension Points

1. Custom Libraries

   • Place in app/Libraries/ and autoload in composer.json:

     "autoload": {
         "psr-4": {
             "App\\": "app/"
         }
     }
     

2. Custom Helpers

   • Add to app/Helpers/ and register in app/Config/Autoloader.php:

     $psr4['App\\Helpers'] = APPPATH . 'Helpers';
     

3. Custom Commands

   • Extend BaseCommand (see CLI Tasks above).

4. Custom Filters