Umbral Realtime

Polling is the sound of a UI that doesn't trust the server to tell it anything. Umbral Realtime pushes instead: target a single user or a whole room, and let an ORM post_save signal fan a change out to everyone watching — a new comment appears, a dashboard counter ticks, a moderation queue lights up — without the browser asking "anything yet?" every two seconds. A default connection cap and per-connection message-rate cap keep one client from flooding the server.

Install

cargo add umbral-realtime

Wire it up

Hang a handler off a model's lifecycle and push when it fires.

use umbral::prelude::*;
use umbral_realtime::{RealtimePlugin, ModelEvent, ModelAction};

let app = App::builder()
    .database("default", pool)
    .plugin(
        RealtimePlugin::default()
            .on_model::<Comment, _, _>(|ev: ModelEvent| async move {
                if ev.action == ModelAction::Created {
                    // notify watchers of this thread
                }
            }),
    )
    .build()?;

Browsers subscribe over SSE at /realtime/sse.

Target: a live, superuser-only notification

Target by user id (never a public group) and only superusers ever receive the event — a normal visitor's connection is never sent it.

use umbral_realtime::Realtime;

Realtime::to_user(admin_id.to_string())
    .send("admin_notification", &payload).await;

What you get

• Push over SSE (WebSocket on the roadmap)
• Target a single user or a named room
• ORM post_save signals fan out changes automatically
• Default connection cap + per-connection message-rate cap
• User-targeted events = private channels with no group to guess