Ensure future

[r0fls]

I'm not sure how this would work exactly with #408 but I'm convinced it's helpful.

[r0fls]

I'll add a test and an example @seemethere then you'll see how awesome this is :P

[r0fls]

This simplifies integration with another server like websockets down to this:

app = sanic.Sanic()

async def time(websocket, path):
    while True:
        now = datetime.datetime.utcnow().isoformat() + 'Z'
        await websocket.send(now)
        await asyncio.sleep(random.random() * 3)

start_server = websockets.serve(time, 'localhost', 3000)
app.ensure_future(start_server)

@app.route('/')
def hello(request):
    return html(open('ws.html').read())

app.run(port=8000)

Instead of how you would probably do this currently:

app = sanic.Sanic()

async def time(websocket, path):
    while True:
        now = datetime.datetime.utcnow().isoformat() + 'Z'
        await websocket.send(now)
        await asyncio.sleep(random.random() * 3)

def init(app, loop):
    start_server = websockets.serve(time, 'localhost', 3000)
    loop.run_until_complete(start_server)

@app.route('/')
def hello(request):
    return html(open('ws.html').read())

app.run(port=8000, before_start=init)

It works with any Future, coroutine or awaitable, since it's just calling the ensure_future method later.

[seemethere]

Maybe a sleep should be added here just in case?

[r0fls]

I do the sleep in the route, but yes that would also work or both wouldn't hurt. But, if you think about the chain of events, 0.1 in the /late route should always be enough. Since the first call to sanic_endpoint_test starts the coro which only sleeps for 0.05 seconds. Then this route (/late) sleeps for twice that time, and doesn't start until afterwards. So, I think it's sufficient length...

[r0fls]

I just dislike those tests that pause for a long time because my heart always sinks thinking I broke something :)

[r0fls]

If you're still not convinced I can add it :)

[seemethere]

No it's okay I think it should be fine.