Implementing Persistent Sessions in Phoenix LiveView

In a detailed guide, Henrik Nyh explains how to maintain persistent session data across Phoenix LiveView sessions. Due to the stateful but ephemeral nature of LiveView processes, traditional methods of modifying sessions are ineffective. Instead, Nyh suggests initiating an Ajax request from the client to the Phoenix server upon user interactions, such as typing in a chat input, to update session storage. This method leverages a cookie-based session that is signed (to prevent tampering) but still readable by the server, allowing session data to persist even after a browser restart. The solution involves setting up a dedicated API endpoint for session updates, controlling session lifetime, and creating a LiveView JavaScript hook to manage the Ajax requests. Furthermore, Nyh illustrates how to handle session updates across multiple LiveViews, allowing for real-time synchronization of session data without page refresh.