HTTP Sessions

The default PHP Sessions do not work seamlessly with Swoole, as they are designed for PHP scripts handling one HTTP request at a time. This limitation necessitated the development of a custom solution to enable sessions in Swoole-based applications.

Understanding Sessions

You can use sessions to persist arbitrary data on the server tied to an HTTP client that supports Cookies.

This data is not necessarily tied to a specific user. It's only related to the specific client.

On the client side, only the session cookie is stored (with the globally unique identifier of the session), and the rest of the data is stored on the server. You can use this to store some volatile data that should not be accessible directly by the HTTP browser.

For example, you can use sessions for storing the contents of an e-commerce shopping basket for the current client device.

Usage

Session Manager relies on Redis for storage and igbinary for data serialization.

Redis connection is obtained from the connection pool only when the session is requested. Sessions do not start automatically with HTTP Requests.

Configuration

You need to specify the session cookie parameters and the desired Redis connection pool that the session manager is going to use:

config.ini
ini
; ...

[session]
cookie_name = dmsession
; lifespan in seconds
cookie_lifespan = 86400
redis_connection_pool = default

; ...

Session Manager

Resonance\SessionManager is a singleton, and you can use it with Dependency Injection.

The typical usage follows the 'start -> modify -> persist' pattern:

php
<?php

/**
 * Start a new session or reuse the session that has already been started for
 * the current request.
 * 
 * `$sessionManager->start()` also sets the session cookie in the response.
 * 
 * @var Resonance\Session $session
 * @var Psr\Http\Message\ServerRequestInterface $request
 * @var Swoole\Http\Response $response
 */
$session = $sessionManager->start($request);

/**
 * Anything that is serializable by igbinary can be used as a value.
 */
$session->data->put('my-data-key', 'my-value');

/**
 * Only now the session data is persisted and stored in the Redis database.
 * Just setting the data in `$session->data` does not persist that data.
 */
$sessionManager->persistSession($request);

If you are using Session Manager from inside the HTTP Responders or Controllers, you do not have to persist the session data manually. Resonance does that after Swoole sends the HTTP response back to the client.