Server Push

Starlette includes support for HTTP/2 and HTTP/3 server push, making it possible to push resources to the client to speed up page load times.

Request.send_push_promise

Used to initiate a server push for a resource. If server push is not available this method does nothing.

Signature: send_push_promise(path)

  • path - A string denoting the path of the resource.
from starlette.applications import Starlette
from starlette.responses import HTMLResponse
from starlette.routing import Route, Mount
from starlette.staticfiles import StaticFiles


async def homepage(request):
    """
    Homepage which uses server push to deliver the stylesheet.
    """
    await request.send_push_promise("/static/style.css")
    return HTMLResponse(
        '<html><head><link rel="stylesheet" href="/static/style.css"/></head></html>'
    )

routes = [
    Route("/", endpoint=homepage),
    Mount("/static", StaticFiles(directory="static"), name="static")
]

app = Starlette(routes=routes)