Comment 4 for bug 1913625

Reviewed: https://review.opendev.org/c/openstack/glance/+/785552
Committed: https://opendev.org/openstack/glance/commit/e87d3fbbe5e0bd404337a0e82b496edc30370e63
Submitter: "Zuul (22348)"
Branch: stable/ussuri

commit e87d3fbbe5e0bd404337a0e82b496edc30370e63
Author: Dan Smith <email address hidden>
Date: Mon Feb 22 12:52:03 2021 -0800

    Add housekeeping module and staging cleaner

    As noted in previous discussions, glance should clean its staging
    directory on startup. This is important for scenarios where we
    started an import operation, but failed in the middle. If, when we
    recover, the image has already been deleted from the database, then
    we will never remove the (potentially very large) residue from disk
    in our staging directory.

    This is currently a problem with web-download, but will also occur
    with glance-direct once we have the non-shared distributed import
    functionality merged.

    Conflicts:
            glance/tests/unit/common/test_wsgi_app.py: Does not exist

    Closes-Bug: #1913625
    Change-Id: Ib80e9cfb58680f9e8ead5993dc206f4da882dd09
    (cherry picked from commit 232177e68c547a815c31a2f30b6d1f95cdb3098d)
    (cherry picked from commit 94679941368d37520975e0a1dc81d27424167191)