Cleanup py27 and docs support

This repo is now testing only with Python 3, so let's make
a few cleanups:
- Remove python 2.7 stanza from setup.py
- Remove obsolete sections from setup.cfg
- Update classifiers
- Update requirements, no need for python_version anymore
- Cleanup doc/source/conf.py to remove now obsolete content,
  use sphinxcontrib.apidoc to build module index again (this
  seems to have been broken when switching to sphinx-build).
- Remove install_command from tox.ini, the default is fine
- Use TOX_CONSTRAINTS_FILE instead of obsolete UPPER_CONSTRAINTS_FILE.
- Update tox.ini for python3 only support.

Change-Id: Id8738ecfb0f578d2a7953c63ffe10779f835bcaf

.gitignore

@@ -1,6 +1,7 @@
 .coverage
 coverage.xml
 cover/*
+doc/source/developer/api/
 *~
 .testrepository
 *.sw?

doc/requirements.txt

@@ -3,6 +3,6 @@
 # process, which may cause wedges in the gate later.
 
 openstackdocstheme>=1.18.1 # 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
 reno>=2.5.0 # Apache-2.0
+sphinxcontrib-apidoc>=0.2.0  # BSD

doc/source/conf.py

@@ -5,7 +5,11 @@ import os
 # extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
 # ones.
 sys.path.append(os.path.abspath('../lib'))
-extensions = ['openstackdocstheme', 'element_deps', 'sphinx.ext.autodoc']
+extensions = ['openstackdocstheme',
+              'element_deps',
+              'sphinx.ext.autodoc',
+              'sphinxcontrib.apidoc'
+]
 
 # Add any paths that contain templates here, relative to this directory.
 templates_path = ['_templates']
@@ -29,18 +33,6 @@ bug_project = 'diskimage-builder'
 bug_tag = ''
 html_last_updated_fmt = '%Y-%m-%d %H:%M'
 
-# The version info for the project you're documenting, acts as replacement for
-# |version| and |release|, also used in various other places throughout the
-# built documents.
-#
-
-import pbr.version
-
-version_info =  pbr.version.VersionInfo('diskimage-builder')
-# The short X.Y version.
-release = version_info.release_string()
-# The full version, including alpha/beta/rc tags.
-version = version_info.version_string()
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.
@@ -244,3 +236,14 @@ texinfo_documents = [
 
 # If true, do not generate a @detailmenu in the "Top" node's menu.
 #texinfo_no_detailmenu = False
+
+# -- sphinxcontrib.apidoc configuration --------------------------------------
+
+apidoc_module_dir = '../../diskimage_builder'
+apidoc_output_dir = 'developer/api'
+apidoc_excluded_paths = [
+    'tests',
+    'block_device.tests',
+    'elements',
+    'lib',
+]

doc/source/developer/index.rst

@@ -12,6 +12,7 @@ Developer Guide
    dib_lint
    stable_interfaces
    vhd_creation
+   Module index <api/modules>
 
 This documentation explains how to get started with creating your own
 disk-image-builder elements as well as some high level concepts for element
@@ -40,7 +41,7 @@ Python module documentation
 ---------------------------
 
 For internal documentation on the DIB python components, see the
-:ref:`modindex`
+:ref:`modindex`.
 
 
 Finding Work
@@ -48,5 +49,5 @@ Finding Work
 
 We maintain a list of low-hanging-fruit tags on launchpad:
 
- * `https://bugs.launchpad.net/diskimage-builder/+bugs?field.tag=low-hanging-fruit`
-   <https://bugs.launchpad.net/diskimage-builder/+bugs?field.tag=low-hanging-fruit>
+* `https://bugs.launchpad.net/diskimage-builder/+bugs?field.tag=low-hanging-fruit
+  <https://bugs.launchpad.net/diskimage-builder/+bugs?field.tag=low-hanging-fruit>`_

requirements.txt

@@ -1,9 +1,8 @@
 # The order of packages is significant, because pip processes them in the order
 # of appearance. Changing the order has an impact on the overall integration
 # process, which may cause wedges in the gate later.
-# NOTE(fdegir): NetworkX 2.3 dropped support for Python 2
-networkx>=1.10,<2.3;python_version<'3.0' # BSD
-networkx>=1.10;python_version>='3.4' # BSD
+
+networkx>=1.10 # BSD
 pbr!=2.1.0,>=2.0.0 # Apache-2.0
 PyYAML>=3.12 # MIT
 six>=1.10.0 # MIT

setup.cfg

@@ -15,26 +15,10 @@ classifier =
     Programming Language :: Python :: 3.5
     Programming Language :: Python :: 3.6
     Programming Language :: Python :: 3.7
+    Programming Language :: Python :: 3.8
     Environment :: Console
 python-requires = >=3.5
 
-[build_sphinx]
-all_files = 1
-build-dir = doc/build
-source-dir = doc/source
-warning-is-error = 1
-
-[pbr]
-autodoc_index_modules = 1
-autodoc_exclude_modules =
-     setup.py
-     diskimage_builder.tests.*
-     diskimage_builder.block_device.tests.*
-     # elements are a weird mix of scripts & python
-     diskimage_builder.elements.*
-     # this is non-pythony stuff
-     diskimage_builder.lib.*
-
 [files]
 packages =
     diskimage_builder

setup.py

@@ -13,17 +13,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-# THIS FILE IS MANAGED BY THE GLOBAL REQUIREMENTS REPO - DO NOT EDIT
 import setuptools
 
-# In python < 2.7.4, a lazy loading of package `pbr` will break
-# setuptools if some other modules registered functions in `atexit`.
-# solution from: http://bugs.python.org/issue15881#msg170215
-try:
-    import multiprocessing  # noqa
-except ImportError:
-    pass
-
 setuptools.setup(
     setup_requires=['pbr>=2.0.0'],
     pbr=True)

test-requirements.txt

@@ -2,8 +2,7 @@
 # of appearance. Changing the order has an impact on the overall integration
 # process, which may cause wedges in the gate later.
 
-pylint==1.7.6;python_version=='2.7' # GPLv2
-pylint;python_version>'3.0' #GPLv2
+pylint>=1.7.1 #GPLv2
 
 fixtures>=3.0.0 # Apache-2.0/BSD
 mock>=2.0.0 # BSD

tox.ini

@@ -1,13 +1,14 @@
 [tox]
 envlist = pep8,pylint,py35,py36,py37,py38
-minversion = 2.0
+minversion = 3.1.1
 skipsdist = True
+ignore_basepython_conflict = True
 
 [testenv]
 usedevelop = True
-install_command = pip install {opts} {packages}
+basepython = python3
 deps=
-      -c{env:UPPER_CONSTRAINTS_FILE:https://opendev.org/openstack/requirements/raw/branch/master/upper-constraints.txt}
+      -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
       -r{toxinidir}/requirements.txt
       -r{toxinidir}/test-requirements.txt
 commands=
@@ -20,17 +21,14 @@ deps = bindep
 commands = bindep test
 
 [testenv:pep8]
-basepython = python3
 commands =
   flake8 {posargs}
   dib-lint
 
 [testenv:pylint]
-basepython = python3
 commands = pylint --rcfile pylint.cfg diskimage_builder
 
 [testenv:venv]
-basepython = python3
 commands = {posargs}
 
 [testenv:func]
@@ -45,7 +43,11 @@ basepython = python3
 commands = python setup.py test --coverage --coverage-package-name diskimage_builder --testr-args='{posargs}'
 
 [testenv:docs]
-deps= -r{toxinidir}/doc/requirements.txt
+deps=
+      -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+      -r{toxinidir}/requirements.txt
+      -r{toxinidir}/test-requirements.txt
+      -r{toxinidir}/doc/requirements.txt
 basepython = python3
 whitelist_externals =
   rm
@@ -55,7 +57,6 @@ commands =
 
 [testenv:releasenotes]
 deps = {[testenv:docs]deps}
-basepython = python3
 commands = sphinx-build -a -W -E -d releasenotes/build/doctrees -b html releasenotes/source releasenotes/build/html
 
 [flake8]
@@ -63,7 +64,6 @@ ignore = E125,E126,E127,H202,H803,W503,W504
 exclude =  .venv,.git,.tox,dist,doc/build,doc/source,*lib/python*,*egg,build,conf.py
 
 [testenv:lower-constraints]
-basepython = python3
 deps =
   -c{toxinidir}/lower-constraints.txt
   -r{toxinidir}/test-requirements.txt