import time
from aiohttp import web
from aiohttp_session import setup, get_session
from aiohttp_session_mongo import MongoStorage
import motor.motor_asyncio as aiomotor
import asyncio


async def handler(request):
    session = await get_session(request)
    last_visit = session['last_visit'] if 'last_visit' in session else None
    session['last_visit'] = time.time()
    text = 'Last visited: {}'.format(last_visit)
    return web.Response(text=text)


async def init_mongo(loop):
    url = "mongodb://localhost:27017"
    conn = aiomotor.AsyncIOMotorClient(
        url, maxPoolSize=2, io_loop=loop)
    db = 'my_db'
    return conn[db]


async def setup_mongo(app, loop):
    db = await init_mongo(loop)

    async def close_mongo(app):
        db.client.close()

    app.on_cleanup.append(close_mongo)
    return db


async def make_app():
    app = web.Application()
    loop = asyncio.get_event_loop()

    db = await setup_mongo(app, loop)
    session_collection = db['sessions']

    max_age = 3600 * 24 * 365 # 1 year
    setup(app, MongoStorage(session_collection, max_age=max_age))

    app.router.add_get('/', handler)
    return app


web.run_app(make_app())