liveview

LiveView refers to a class of technologies that enable real-time, interactive web user interfaces by keeping most of the application logic on the server and updating the client through a persistent connection. Instead of delivering a static HTML page that then relies heavily on client-side JavaScript, a live view maintains an active connection—commonly via WebSockets—and sends small HTML diffs to the browser as the server state changes.

On the client, a lightweight JavaScript component establishes the connection and applies DOM diffs received from the server. When the user interacts with the page, events are sent back to the server, which updates its state, renders a new HTML fragment, and transmits the changes. This approach can preserve accessibility and search engine optimization because the initial rendering is server-generated, while delivering a dynamic experience without writing large amounts of JavaScript.

Phoenix LiveView is a prominent implementation of this concept within the Elixir-based Phoenix web framework. It renders user interfaces on the server and streams updates to the browser. Each connected user runs a live view process on the server; the server computes a diff of the DOM and sends patches to the client. Live views can compose with live components for reusable UI parts, and they support forms, validation, and file uploads handled in server code.

Benefits of live views include reduced JavaScript complexity and real-time interactivity with server-rendered HTML advantages. Limitations include the need for persistent connections and additional server resources, sensitivity to latency, and potential suitability trade-offs for highly interactive client-side applications or offline use cases.