starlette/docs/applications.md

Starlette also includes an App class that nicely ties together all of its other functionality.

from starlette.app import App
from starlette.response import PlainTextResponse
from starlette.staticfiles import StaticFiles


app = App()
app.mount("/static", StaticFiles(directory="static"))


@app.route('/')
def homepage(request):
    return PlainTextResponse('Hello, world!')


@app.route('/user/{username}')
def user(request, username):
    return PlainTextResponse('Hello, %s!' % username)


@app.websocket_route('/ws')
async def websocket_endpoint(session):
    await session.accept()
    await session.send_text('Hello, websocket!')
    await session.close()

Adding routes to the application

You can use any of the following to add handled routes to the application:

• .add_route(path, func, methods=["GET"]) - Add an HTTP route. The function may be either a coroutine or a regular function, with a signature like func(request **kwargs) -> response.
• .add_websocket_route(path, func) - Add a websocket session route. The function must be a coroutine, with a signature like func(session, **kwargs).
• .mount(prefix, app) - Include an ASGI app, mounted under the given path prefix
• .route(path) - Add an HTTP route, decorator style.
• .websocket_route(path) - Add a WebSocket route, decorator style.