Quick Start

Get your first SSE endpoint up and running in 3 steps — no configuration required.

---

1. Write a generator view

myapp/views.py

import time
from django_flosse import sse_stream, SSEEvent
from django_flosse.permissions import IsAuthenticated


@sse_stream(permission_classes=[IsAuthenticated])
def progress(request):
    for i in range(1, 11):
        yield ("progress", {"step": i, "total": 10, "pct": i * 10})
        time.sleep(1)

    yield SSEEvent(data="All done!", event="complete")

What's happening here?

• @sse_stream turns your generator into a fully-featured SSE endpoint.
• Each yield sends an event to the browser immediately.
• SSEEvent gives you full control over the event name, ID, and retry delay.
• IsAuthenticated blocks unauthenticated requests with a 403.

---

2. Wire up the URL

myapp/urls.py

from django.urls import path
from .views import progress

urlpatterns = [
    path("sse/progress/", progress),
]

---

3. Listen in the browser

myapp/templates/progress.html

const source = new EventSource("/sse/progress/");

source.addEventListener("progress", (e) => {
    const { step, total, pct } = JSON.parse(e.data);
    console.log(`Step ${step}/${total} — ${pct}%`);
});

source.addEventListener("complete", (e) => {
    console.log(e.data); // "All done!"
    source.close();
});

source.addEventListener("error", () => {
    source.close();
});

---

What you get for free

Every @sse_stream view automatically handles:

What	How
Correct headers	Content-Type: text/event-stream
No proxy buffering	X-Accel-Buffering: no
No caching	Cache-Control: no-cache, no-transform
Permission checks	Returns 403 if any class denies access
Error events	Exceptions are streamed as event: error
JSON serialisation	Dicts and non-strings are serialised for you

---

Next steps

• Yield Styles

  Learn all the ways you can yield events.

  Yield Styles

• Permissions

  Protect your streams with built-in or custom permission classes.

  Permissions

• Heartbeats

  Keep connections alive when proxies might close idle streams.

  Heartbeats

• Deployment

  Run in production with Gunicorn, Uvicorn, or Nginx.

  Deployment