Response

The Io library also handles HTTP responses — setting status codes, headers, content, and sending JSON or HTML back to the client.

It is available in controllers via $this->io.

Overview

A typical response is built in three steps:

1. Set a status code with set_status_code()

2. Set headers and content

3. Call send() to flush everything to the client

<?php
$this->response->set_status_code(200);
$this->response->set_html_content('<h1>Hello World</h1>');
$this->response->send();

Setting a Status Code

<?php
$this->response->set_status_code(200);   // OK
$this->response->set_status_code(201);   // Created
$this->response->set_status_code(400);   // Bad Request
$this->response->set_status_code(401);   // Unauthorized
$this->response->set_status_code(403);   // Forbidden
$this->response->set_status_code(404);   // Not Found
$this->response->set_status_code(500);   // Internal Server Error

Adding Headers

Single header:

<?php
$this->response->add_header('Cache-Control', 'no-cache');

Multiple headers at once (pass an array):

<?php
$this->response->add_header([
    'Cache-Control'             => 'no-store',
    'X-Content-Type-Options'    => 'nosniff',
    'X-Frame-Options'           => 'DENY',
]);

Note

Headers are queued internally and only sent when send() is called.

Setting Content

Plain or HTML content:

<?php
$this->response->set_content('<p>Hello</p>');

HTML content (automatically adds ``Content-Type: text/html``):

<?php
$this->response->set_html_content('<h1>Welcome</h1>');

Sending the Response

send() flushes the status code, all queued headers, and the content body:

<?php
$this->response->set_status_code(200);
$this->response->add_header('X-Custom-Header', 'value');
$this->response->set_html_content('<p>Response body</p>');
$this->response->send();

Sending a JSON Response

send_json() automatically sets Content-Type: application/json, encodes the data, and calls send():

<?php
$this->response->set_status_code(200);
$this->response->send_json([
    'status'  => 'success',
    'message' => 'User created',
    'id'      => 42,
]);

JSON error response:

<?php
$this->response->set_status_code(422);
$this->response->send_json([
    'status'  => 'error',
    'message' => 'Validation failed',
    'errors'  => [
        'email' => 'The email field is required.',
    ],
]);

Common Response Patterns

200 OK with JSON data:

<?php
public function show($id)
{
    $this->call->model('UserModel');
    $user = $this->UserModel->find($id);

    if (!$user) {
        $this->response->set_status_code(404);
        $this->response->send_json(['message' => 'User not found']);
    }

    $this->response->set_status_code(200);
    $this->response->send_json($user);
}

201 Created after insert:

<?php
public function store()
{
    $this->call->model('UserModel');
    $id = $this->UserModel->insert($this->response->post());

    $this->response->set_status_code(201);
    $this->response->send_json(['message' => 'Created', 'id' => $id]);
}

204 No Content after delete:

<?php
public function destroy($id)
{
    $this->call->model('UserModel');
    $this->UserModel->delete($id);

    $this->response->set_status_code(204);
    $this->response->send();
}

HTML response with custom headers:

<?php
public function page()
{
    $this->response->set_status_code(200);
    $this->response->add_header('X-Frame-Options', 'SAMEORIGIN');
    $this->response->set_html_content('<h1>Hello from LavaLust</h1>');
    $this->response->send();
}

Redirect using a header:

<?php
public function old_page()
{
    $this->response->set_status_code(301);
    $this->response->add_header('Location', '/new-page');
    $this->response->send();
}

Method Reference

Method	Returns	Description
set_status_code($code)	void	Sets the HTTP response status code
add_header($name, $value)	void	Queues one or more response headers
set_content($content)	void	Sets the raw response body
set_html_content($content)	void	Sets the response body and adds Content-Type: text/html
send()	void	Sends the status code, all queued headers, and the content body
send_json($data)	void	Encodes $data as JSON, sets Content-Type: application/json, and sends