glanceclient doesn't cleanup session it creates if one is not provided

[Alex Schultz]

If a session object is not provided to the glance client, the HTTPClient defined in glanceclient.common.http will create a session object. This session object leaks open connections because it is not properly closed when the object is no longer needed. This leads to a ResourceWarning about an unclosed socket:

sys:1: ResourceWarning: unclosed <ssl.SSLSocket fd=3, family=AddressFamily.AF_INET, type=SocketKind.SOCK_STREAM, proto=6, laddr=('192.168.24.2', 55912), raddr=('192.168.24.2', 13292)>

Example code:

$ cat g.py
#!/usr/bin/python3 -Wd
import glanceclient.common.http as h
client = h.get_http_client(endpoint='https://192.168.24.2:13292',
                           token='<my magical token>',
                           cacert='/etc/pki/ca-trust/source/anchors/cm-local-ca.pem',
                           insecure=False)
print(client.get('/v2/images'))

Results in:

$ ./g.py
/usr/lib64/python3.6/importlib/_bootstrap_external.py:426: ImportWarning: Not importing directory /usr/lib/python3.6/site-packages/repoze: missing __init__
  _warnings.warn(msg.format(portions[0]), ImportWarning)
/usr/lib64/python3.6/importlib/_bootstrap_external.py:426: ImportWarning: Not importing directory /usr/lib/python3.6/site-packages/paste: missing __init__
  _warnings.warn(msg.format(portions[0]), ImportWarning)
/usr/lib/python3.6/site-packages/pytz/__init__.py:499: ResourceWarning: unclosed file <_io.TextIOWrapper name='/usr/share/zoneinfo/zone.tab' mode='r' encoding='UTF-8'>
  for l in open(os.path.join(_tzinfo_dir, 'zone.tab'))
/usr/lib/python3.6/site-packages/eventlet/patcher.py:1: DeprecationWarning: the imp module is deprecated in favour of importlib; see the module's documentation for alternative uses
  import imp
(<Response [200]>, {'images': [{<image data>}], 'first': '/v2/images', 'schema': '/v2/schemas/images'})
sys:1: ResourceWarning: unclosed <ssl.SSLSocket fd=3, family=AddressFamily.AF_INET, type=SocketKind.SOCK_STREAM, proto=6, laddr=('192.168.24.2', 55912), raddr=('192.168.24.2', 13292)>

This can be mitigated by adding a __del__ function to glanceclient.common.http.HTTPClient that closes the session.

[Alex Schultz (alex-schultz)]

https://review.opendev.org/#/c/674133/

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/674133
Committed: https://git.openstack.org/cgit/openstack/python-glanceclient/commit/?id=436f797e8db2fc11b7dace7cb7020e4d44a3d2d7
Submitter: Zuul
Branch: master

commit 436f797e8db2fc11b7dace7cb7020e4d44a3d2d7
Author: Alex Schultz <email address hidden>
Date: Thu Aug 1 14:39:46 2019 -0600

    Cleanup session object

    If a session object is not provided to the get_http_client function (as
    is done via osc), the glance client uses it's own HTTPClient class. This
    class creates a session but does not properly close it when it is done.
    This can lead to resource warnings about unclosed sockets. This change
    adds a __del__() to the HTTPClient class to close out the session
    correctly.

    Change-Id: Idccff338fa84c46ca0e429bb533a2a5217205eef
    Closes-Bug: #1838694

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/python-glanceclient 3.0.0 release.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/train
Review: https://review.opendev.org/712461

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/712461
Committed: https://git.openstack.org/cgit/openstack/python-glanceclient/commit/?id=1aba8f2d248040364e690dd8dc7f3a508baed631
Submitter: Zuul
Branch: stable/train

commit 1aba8f2d248040364e690dd8dc7f3a508baed631
Author: Alex Schultz <email address hidden>
Date: Thu Aug 1 14:39:46 2019 -0600

    Cleanup session object

    If a session object is not provided to the get_http_client function (as
    is done via osc), the glance client uses it's own HTTPClient class. This
    class creates a session but does not properly close it when it is done.
    This can lead to resource warnings about unclosed sockets. This change
    adds a __del__() to the HTTPClient class to close out the session
    correctly.

    Change-Id: Idccff338fa84c46ca0e429bb533a2a5217205eef
    Closes-Bug: #1838694
    (cherry picked from commit 436f797e8db2fc11b7dace7cb7020e4d44a3d2d7)