Complete "Drop Python 2.7 Support" goal

The goal definition in the TC repo [1] defines the completion criteria.
We have already completed 1, 2, 3 and partially 4 in [1].
This commit completes 4 (requirements.txt etc) and 5 (release note).

Python dependency in the installation guide is updated.
Django support plan in Ussuri is updated as well.
References to python 2.7 in the document are updated as well.

[1] https://governance.openstack.org/tc/goals/selected/ussuri/drop-py27.html

Change-Id: I0383920e32e053e1611519be774fab8dec124ccc

doc/requirements.txt

@@ -7,8 +7,7 @@
 # be installed in a specific order.
 openstackdocstheme>=1.20.0 # Apache-2.0
 reno>=2.5.0 # Apache-2.0
-sphinx!=1.6.6,!=1.6.7,>=1.6.2,<2.0.0;python_version=='2.7' # BSD
-sphinx!=1.6.6,!=1.6.7,!=2.1.0,>=1.6.2;python_version>='3.4' # BSD
+sphinx!=1.6.6,!=1.6.7,!=2.1.0,>=1.6.2 # BSD
 doc8>=0.6.0 # Apache-2.0
 
 # The below is rewquired to build testing module reference

doc/source/contributor/quickstart.rst

@@ -21,13 +21,6 @@ On Ubuntu
 
     $ sudo apt-get install git python3-dev python3-pip
 
-To get a full python2.7 development environment, you also need to install
-the following packages:
-
-.. code-block:: console
-
-    python-dev
-
 On RPM-based distributions (e.g., Fedora/RHEL/CentOS)
 
 .. code-block:: console

doc/source/contributor/testing.rst

@@ -76,11 +76,11 @@ pep8
 Runs pep8, which is a tool that checks Python code style. You can read more
 about pep8 at https://www.python.org/dev/peps/pep-0008/
 
-py27
+py37
 ----
 
 Runs the Python unit tests against the current default version of Django
-with Python 2.7 environment. Check ``requirements.txt`` in horizon
+with Python 3.7 environment. Check ``requirements.txt`` in horizon
 repository to know which version of Django is actually used.
 
 All other dependencies are as defined by the upper-constraints file at
@@ -89,20 +89,20 @@ https://opendev.org/openstack/requirements/raw/branch/master/upper-constraints.t
 You can run a subset of the tests by passing the test path as an argument to
 tox::
 
-  $ tox -e py27 -- openstack_dashboard.dashboards.identity.users.tests
+  $ tox -e py37 -- openstack_dashboard.dashboards.identity.users.tests
 
 The following is more example to run a specific test class and a
 specific test:
 
 .. code-block:: console
 
-   $ tox -e py27 -- openstack_dashboard.dashboards.identity.users.tests:UsersViewTests
-   $ tox -e py27 -- openstack_dashboard.dashboards.identity.users.tests:UsersViewTests.test_index
+   $ tox -e py37 -- openstack_dashboard.dashboards.identity.users.tests:UsersViewTests
+   $ tox -e py37 -- openstack_dashboard.dashboards.identity.users.tests:UsersViewTests.test_index
 
 You can also pass other arguments. For example, to drop into a live debugger
 when a test fails you can use::
 
-  $ tox -e py27 -- --pdb
+  $ tox -e py37 -- --pdb
 
 py3-dj111, py3-dj21, py3-dj22
 -----------------------------
@@ -115,11 +115,6 @@ py36
 
 Runs the Python unit tests with a Python 3.6 environment.
 
-py37
-----
-
-Runs the Python unit tests with a Python 3.7 environment.
-
 releasenotes
 ------------
 

doc/source/contributor/topics/packaging.rst

@@ -203,8 +203,8 @@ Packaging Horizon for distributions
 
 Horizon is a Python module. Preferably, it is installed at the default
 location for python. In Fedora and openSUSE, this is
-``/usr/lib/python2.7/site-packages/horizon``, and in Debian/Ubuntu it is
-``/usr/lib/python2.7/dist-packages/horizon``.
+``/usr/lib/python3.7/site-packages/horizon``, and in Debian/Ubuntu it is
+``/usr/lib/python3.7/dist-packages/horizon``.
 
 Configuration files should reside under ``/etc/openstack-dashboard``.
 Policy files should be created and modified there as well.

doc/source/install/system-requirements.rst

@@ -2,20 +2,16 @@
 System Requirements
 ===================
 
-The Train release of horizon has the following dependencies.
+The Ussuri release of horizon has the following dependencies.
 
-* Python 2.7, 3.6 or 3.7
+* Python 3.6 or 3.7
 
-* Django 1.11, 2.0 and 2.2
+* Django 2.2
 
-  * Django 2.0 and 2.2 support are experimental in Train release.
-
-    * Note that Ussuri release (the upcoming release after Train release)
-      will use Django 2.2 as the primary Django version.
-      Django 2.0 support will be dropped.
-
-  * Django 1.8 to 1.10 are no longer supported since Rocky release.
   * Django support policy is documented at :doc:`/contributor/policy`.
+  * Ussuri release uses Django 2.2 (the latest LTS) as the primary Django
+    version. The prevouos LTS of Django 1.11 will be dropped during
+    Ussuri cycle. Django 2.0 support will be dropped as well.
 
 * An accessible `keystone <https://docs.openstack.org/keystone/latest/>`_ endpoint
 

releasenotes/notes/drop-python27-support-160366ba52a1205b.yaml

@@ -0,0 +1,6 @@
+---
+upgrade:
+  - |
+    Python 2.7 support has been dropped. Last release of horizon
+    to support python 2.7 is OpenStack Train. The minimum version of Python now
+    supported by horizon is Python 3.6.

requirements.txt

@@ -11,8 +11,7 @@ pbr!=2.1.0,>=2.0.0 # Apache-2.0
 # Horizon Core Requirements
 Babel!=2.4.0,>=2.3.4 # BSD
 debtcollector>=1.2.0 # Apache-2.0
-Django<2,>=1.11;python_version<'3.0'  # BSD
-Django>=1.11;python_version>='3.0'  # BSD
+Django>=1.11 # BSD
 django-babel>=0.6.2 # BSD
 django-compressor>=2.0 # MIT
 django-debreach>=1.4.2 # BSD License (2 clause)

test-requirements.txt

@@ -9,7 +9,7 @@
 # Hacking should appear first in case something else depends on pep8
 hacking>=1.1.0,<2 # Apache-2.0
 #
-astroid==2.1.0;python_version>='3.0' # LGPLv2.1
+astroid==2.1.0 # LGPLv2.1
 bandit!=1.6.0,>=1.4.0 # Apache-2.0
 coverage!=4.4,>=4.0 # Apache-2.0
 flake8-import-order==0.12 # LGPLv3
@@ -17,7 +17,7 @@ mock>=2.0.0 # BSD
 mox3>=0.20.0 # Apache-2.0
 nodeenv>=0.9.4 # BSD
 python-memcached>=1.59 # PSF
-pylint==2.2.2;python_version>='3.0' # GPLv2
+pylint==2.2.2 # GPLv2
 selenium>=2.50.1 # Apache-2.0
 testscenarios>=0.4 # Apache-2.0/BSD
 testtools>=2.2.0 # MIT