Magento Request/Response

The Request object provides access to all HTTP request data.

Getting request data:

$request = $this->getRequest();

// URL parameters
$id = $request->getParam('id');
$page = $request->getParam('p', 1); // With default

// POST data
$postData = $request->getPostValue();
$title = $request->getPostValue('title');

// All parameters
$allParams = $request->getParams();

// HTTP method
$method = $request->getMethod(); // GET, POST, PUT, DELETE

// Request URI
$uri = $request->getRequestUri();
$pathInfo = $request->getPathInfo();

// Headers
$accept = $request->getHeader('Accept');
$contentType = $request->getHeader('Content-Type');

Request object methods:

// Route information
$routeName = $request->getRouteName();
$controllerName = $request->getControllerName();
$actionName = $request->getActionName();

// Set parameters (for forwarding)
$request->setParam('key', 'value');
$request->setRouteName('catalog');
$request->setControllerName('product');
$request->setActionName('view');

// Check request type
$isPost = $request->isPost();
$isGet = $request->isGet();
$isAjax = $request->isAjax();

JSON request body:

$jsonData = $request->getContent();
$data = json_decode($jsonData, true);

The Response object controls the HTTP response sent to the client.

Setting response data:

$response = $this->getResponse();

// Set body
$response->setBody('Hello World');
$response->setBody(json_encode($data));

// Set headers
$response->setHeader('Content-Type', 'application/json');
$response->setHeader('X-Custom-Header', 'value');

// Remove header
$response->setHeader('X-Custom-Header', null, true);

// Set HTTP status code
$response->setStatusCode(200); // OK
$response->setStatusCode(404); // Not Found
$response->setStatusCode(500); // Server Error

Response for JSON API:

public function execute()
{
    $data = ['status' => 'success', 'message' => 'Saved'];
    
    $response = $this->getResponse();
    $response->setHeader('Content-Type', 'application/json');
    $response->setBody(json_encode($data));
    
    return $response;
}

Response for file download:

public function execute()
{
    $response = $this->getResponse();
    $response->setHeader('Content-Type', 'text/csv');
    $response->setHeader('Content-Disposition', 'attachment; filename="export.csv"');
    $response->setHeader('Content-Transfer-Encoding', 'binary');
    $response->setBody($csvContent);
    
    return $response;
}

Managing HTTP headers and cookies in Magento.

HTTP headers:

// Set header
$this->getResponse()->setHeader('Content-Type', 'text/html');

// Set multiple headers
$this->getResponse()->setHeader('Cache-Control', 'no-cache, no-store');
$this->getResponse()->setHeader('Pragma', 'no-cache');

// Check if header exists
if ($this->getResponse()->canSetHeaders()) {
    $this->getResponse()->setHeader('X-Frame-Options', 'SAMEORIGIN');
}

Cookies:

// Get cookie value
$value = $this->getRequest()->getCookieValue('cookie_name');

// Set cookie via CookieManager
$cookieManager = $this->_objectManager->get(
    \Magento\Framework\Stdlib\Cookie\CookieManagerInterface::class
);

$cookieManager->setCookie(
    'cookie_name',
    'cookie_value',
    [
        'path' => '/',
        'domain' => '.example.com',
        'httponly' => true,
        'secure' => true,
        'lifetime' => 3600
    ]
);

// Delete cookie
$cookieManager->deleteCookie('cookie_name');

Session:

// Get session
$session = $this->_objectManager->get(
    \Magento\Framework\Session\SessionManagerInterface::class
);

// Set session data
$session->setData('key', 'value');

// Get session data
$value = $session->getData('key');

// Clear session
$session->unsData('key');

Proper HTTP status codes for API and web responses.

Common status codes:

200 OK — Successful request
201 Created — Resource created
204 No Content — Successful, no response body
301 Moved Permanently — Permanent redirect
302 Found — Temporary redirect
400 Bad Request — Invalid input
401 Unauthorized — Authentication required
403 Forbidden — Permission denied
404 Not Found — Resource doesn't exist
405 Method Not Allowed — HTTP method not supported
422 Unprocessable Entity — Validation failed
500 Internal Server Error — Server error
503 Service Unavailable — Service down

Setting status codes:

// In controller
$this->getResponse()->setStatusCode(404);
$this->getResponse()->setBody(__('Page not found'));return $this->getResponse();

// JSON API response
public function execute()
{
    try {
        $result = $this->service->process();
        
        $response = $this->getResponse();
        $response->setStatusCode(200);
        $response->setHeader('Content-Type', 'application/json');
        $response->setBody(json_encode($result));
        
        return $response;
    } catch (\Exception $e) {
        $response = $this->getResponse();
        $response->setStatusCode(500);
        $response->setHeader('Content-Type', 'application/json');
        $response->setBody(json_encode(['error' => $e->getMessage()]));
        
        return $response;
    }
}

REST API status codes:

// GET success: 200
// POST success: 201
// PUT success: 200
// DELETE success: 204
// Validation error: 422
// Not found: 404
// Unauthorized: 401