Requests and responses

A request is what the browser sent to the site: the address, parameters, form fields. A response is what the site sends back. In a controller the request is available as $this->request and the response as $this->response. There is no need to create them: both objects come from BaseController.

Address parameters

Parameters after the question mark are read with getGet():

// app/Controllers/Posts.php
public function search(): string
{
    $query = $this->request->getGet('q');
 
    return 'You searched for: ' . esc($query);
}

Add the route $routes->get('search', 'Posts::search'); and open /search?q=php — the page shows "You searched for: php". If the parameter is missing, getGet() returns null. The esc() function makes text safe to output; the lesson about views covers it.

Form fields

Data sent by a form with the POST method is read with getPost():

public function create(): string
{
    $title = $this->request->getPost('title');
 
    return 'Title received: ' . esc($title);
}

Without an argument getPost() returns an array of all fields.

Other request methods

Method	What it returns
`getGet('q')`	An address parameter
`getPost('title')`	A form field
`getJSON(true)`	The JSON request body as an array
`getMethod()`	The request method: `GET`, `POST`
`is('post')`	`true` if the request was sent with POST
`getIPAddress()`	The visitor's address

Redirect

After a form is saved the visitor is sent to another page:

public function create()
{
    // the data is saved here
 
    return redirect()->to('/posts');
}

The browser opens /posts by itself. There are other variants too:

return redirect()->route('posts.show', [5]); // by route name
return redirect()->back();                   // to the previous page

A JSON response

JSON is a text data format understood by JavaScript programs and mobile apps:

public function status()
{
    return $this->response->setJSON(['status' => 'ok', 'posts' => 12]);
}

The browser receives a string like {"status":"ok","posts":12} and a header with the application/json type.

Status code

The status code tells how the request ended: 200 is success, 404 is not found. setStatusCode() sets it:

return $this->response->setStatusCode(404)->setBody('Post not found');

Common mistake

Calling redirect()->to('/posts'); without the word return does nothing: the function only creates a response object, and the framework sends it after receiving it from the method. The method keeps running and the visitor stays on a blank page. Always write return before redirect().

Thanks for reading!