Issue #1652: Requests sessions stay around after a koji.ClientSession object is out of scope - koji

koji

#1652 Requests sessions stay around after a koji.ClientSession object is out of scope

Closed: Fixed Sep 23, 2019 by mikem. Opened Sep 19, 2019 by mprahl.

On the Module Build Service (MBS) backend, I've noticed hundreds of TCP connections in the "CLOSE_WAIT" state to the Koji hub. This seems to stem from the fact that koji.ClientSession objects don't close the underlying requests (as in python-requests) session after the koji.ClientSession goes out of scope. It's possible the garbage collector isn't actually destroying these koji.ClientSession objects. Interestingly enough, this only happens on Python 2.

Here is a reproducer script:

import gc
import os
import time
import koji
import psutil
def get_num_connections():
    return len(psutil.Process(os.getpid()).connections())
def get_session():
    session = koji.ClientSession('https://koji.fedoraproject.org/kojihub')
    session.getBuild(1382202)
print('Starting with {} connections'.format(get_num_connections()))
for i in range(20):
    get_session()
print(
    '{} connections after requesting 20 Koji sessions that are now out of scope'
    .format(get_num_connections())
)
gc.collect()
time.sleep(10)
print(
    '{} connections after running the garbage collector and sleeping for 10 seconds'
    .format(get_num_connections())
)