Is there a way to log python print statements in gunicorn?

Question

With my Procfile like this:

web: gunicorn app:app \
    --bind "$HOST:$PORT" \
    --error-logfile "-" \
    --enable-stdio-inheritance \
    --reload \
    --log-level "debug" 

is it in any way possible to get python print statements to be logged to stdout / bash? I am using the bottle framework here as well, if that affects anything.

Answer 1

It turns out the print statements were actually getting through, but with delay.

The gunicorn docs for --enable-stdio-inheritance note to set the PYTHONUNBUFFERED, which I thought I had, but it seems with wrong syntax.

I solved it using a .env file with my foreman setup to set the variable like this:

PYTHONUNBUFFERED=TRUE