Fix multiple CI failures

1. Clean up some requirements

* Drop the py26 marker for futures; we don't support 2.6 anymore.
* Split hacking version used based on python version.
* Clean up sphinx split -- 2.0+ aren't available to install on py2,
  anyway.

Depends-On: https://review.opendev.org/#/c/752340/
Depends-On: https://review.opendev.org/#/c/752736/
(cherry picked from commit 5cb906148709ccc74ca96463fd69a5cae2381edb)

2. Drop lower-constraints testing

The OpenStack community consensus seems to be that it's not worth the
hassle of fixing. *Maybe* we can revisit this if we ever drop py2
support?

Reasonable spot to start on ML threads:
http://lists.openstack.org/pipermail/openstack-discuss/2021-January/019672.html

(cherry picked from commit 06b36ae0e2ee6054162bfb1d9f3cdda39eacbad5)

3. [goal] Migrate testing to ubuntu focal

As per victoria cycle testing runtime and community goal[1]
we need to migrate upstream CI/CD to Ubuntu Focal(20.04).

- Keep py2 functional job run on Bionic node

Story: #2007865
Task: #40221

(cherry picked from commit 9f69908f759daafc99a162b136b24570a2822ee2)

tests: Make test_delete_container_versions less flakey

Hammering that test in a tight loop, I'd often see failures due to
ordering issues. Make the delete single-threaded to avoid that.

(cherry picked from commit c73792c2e55e4fbdff78a192a991e064a317e840)

Change-Id: I5a6ba8e65c23ada7297f6684dcbdd886591d0af5

7 files changed, 8 insertions, 59 deletions

diff --git a/.zuul.yaml b/.zuul.yaml
index 87ac54b..70db8ab 100644
--- a/.zuul.yaml
+++ b/.zuul.yaml
@@ -23,10 +23,13 @@
     vars:
       # Override value from parent job to use swiftclient tests
       zuul_work_dir: "{{ zuul.projects['opendev.org/openstack/python-swiftclient'].src_dir }}"
+      # swift can use different tox env names
+      tox_envlist: func
 
 - job:
     name: swiftclient-functional-py2
     parent: swiftclient-functional
+    nodeset: openstack-single-node-bionic
     description: |
       Run functional tests of python-swiftclient under Python 2
     vars:
@@ -36,7 +39,6 @@
     templates:
       - check-requirements
       - lib-forward-testing-python3
-      - openstack-lower-constraints-jobs
       - openstack-python-jobs
       - openstack-python3-victoria-jobs
       - publish-openstack-docs-pti
diff --git a/doc/requirements.txt b/doc/requirements.txt
index 3ee9fc2..5700e3b 100644
--- a/doc/requirements.txt
+++ b/doc/requirements.txt
@@ -1,5 +1,4 @@
 keystoneauth1>=3.4.0  # Apache-2.0
-sphinx!=1.6.6,!=1.6.7,<2.0.0,>=1.6.2;python_version=='2.7' # BSD
-sphinx>=2.0.0,!=2.1.0;python_version>='3.4' # BSD
+sphinx>=1.6.2,!=1.6.6,!=1.6.7,!=2.1.0,!=3.0.0  # BSD
 reno>=2.5.0 # Apache-2.0
 openstackdocstheme>=1.31.2 # Apache-2.0
diff --git a/lower-constraints.txt b/lower-constraints.txt
deleted file mode 100644
index 1e4ffb9..0000000
--- a/lower-constraints.txt
+++ /dev/null
@@ -1,46 +0,0 @@
-alabaster==0.7.10
-Babel==2.3.4
-certifi==2018.1.18
-chardet==3.0.4
-coverage==4.0
-docutils==0.11
-dulwich==0.15.0
-extras==1.0.0
-fixtures==3.0.0
-flake8==2.2.4
-futures==3.0.0
-hacking==0.10.0
-idna==2.6
-imagesize==0.7.1
-iso8601==0.1.8
-Jinja2==2.10
-keystoneauth1==3.4.0
-linecache2==1.0.0
-MarkupSafe==1.0
-mccabe==0.2.1
-mock==1.2.0
-netaddr==0.7.10
-openstackdocstheme==2.0.0
-openstacksdk==0.11.0
-oslo.config==1.2.0
-pbr==2.0.0
-pep8==1.5.7
-PrettyTable==0.7.1
-pyflakes==0.8.1
-Pygments==2.2.0
-python-keystoneclient==0.7.0
-python-mimeparse==1.6.0
-python-subunit==1.0.0
-pytz==2013.6
-PyYAML==3.12
-reno==2.5.0
-requests==1.1.0
-six==1.9.0
-snowballstemmer==1.2.1
-sphinx==2.0.0
-sphinxcontrib-websupport==1.0.1
-stestr==2.0.0
-testtools==2.2.0
-traceback2==1.4.0
-unittest2==1.1.0
-urllib3==1.22
diff --git a/requirements.txt b/requirements.txt
index 1c2ce33..4757239 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,3 +1,3 @@
-futures>=3.0.0;python_version=='2.7' or python_version=='2.6' # BSD
+futures>=3.0.0;python_version=='2.7' # BSD
 requests>=1.1.0
 six>=1.9.0
diff --git a/test-requirements.txt b/test-requirements.txt
index 5dba1a6..c2fb2c6 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -1,4 +1,5 @@
-hacking>=1.1.0,<1.2.0 # Apache-2.0
+hacking>=1.1.0,<1.2.0;python_version<'3.0' # Apache-2.0
+hacking>=3.2.0,<3.3.0;python_version>='3.0' # Apache-2.0
 
 coverage!=4.4,>=4.0 # Apache-2.0
 keystoneauth1>=3.4.0  # Apache-2.0
diff --git a/test/unit/test_shell.py b/test/unit/test_shell.py
index f94e5e2..46ba52c 100644
--- a/test/unit/test_shell.py
+++ b/test/unit/test_shell.py
@@ -1547,7 +1547,7 @@ class TestShell(unittest.TestCase):
             [None, []],
         ]
         connection.return_value.attempts = 0
-        argv = ["", "delete", "--versions", "container"]
+        argv = ["", "delete", "--versions", "container", "--object-threads=1"]
         connection.return_value.head_object.return_value = {}
         swiftclient.shell.main(argv)
         connection.return_value.delete_container.assert_called_with(
diff --git a/tox.ini b/tox.ini
index 4131436..0837a06 100644
--- a/tox.ini
+++ b/tox.ini
@@ -102,13 +102,6 @@ usedevelop = False
 deps = -r{toxinidir}/doc/requirements.txt
 commands = sphinx-build -a -W -E -d releasenotes/build/doctrees -b html releasenotes/source releasenotes/build/html
 
-[testenv:lower-constraints]
-basepython = python3
-deps =
-  -c{toxinidir}/lower-constraints.txt
-  -r{toxinidir}/test-requirements.txt
-  .[keystone]
-
 [testenv:pdf-docs]
 basepython = python3
 deps = {[testenv:docs]deps}