How to add an additional handler to default logger?

[ockan]

I code

app = Application(__name__)
from logging.handlers import RotatingFileHandler
handler = RotatingFileHandler("app.log", maxBytes=10240, backupCount=3)
app.logger.addHandler(handler)

then

@app.route('/')
async def index(request, **server):
    session = request.ctx.session
    logger = server['logger']
    logger.info('Current page: /')
    if session is None or not session.is_logged_in():
        return b'You are not logged in. <a href="/login">Login</a>.'

    return b'Welcome to Dashboard. <a href="/logout">Logout</a>.'

the logging just print on console, not in 'app.log'('app.log' file created,but still blank)

[nggit]

The logger handler behaviour is not reliably inherited to child process. When you do it in main. Especially when using spawn / Windows?

What if you do it inside @app.on_worker_start?

@app.on_worker_start
async def worker_start(app):
    handler = RotatingFileHandler("app.log", maxBytes=10240, backupCount=3)
    app.logger.addHandler(handler)


@app.route('/')
async def index(request, logger, **server):
    session = request.ctx.session
    logger.info('Current page: /')

[ockan]

this works. it is unimaginably queer

[nggit]

It's expected. app inside worker_start hook is a worker's app, a completely separated app object than the main's.

If you want the same object, true single process (no worker) use Tremolo.serve() rather than Tremolo.run() e.g:

asyncio.run(app.serve(host, port))