Remove centos7 job, python2 support

This change does the following:
- Removes the centos7 job, it uses python2 even though python2 was
  dropped from IPA in 2019.
  (see Ifd0e0b99bb82a7d7e82d6c14309468196f5734fc)
- Allow 60-ironic-python-agent-ramdisk-install to assume python3 and
  the venv module, the remaining centos7-python3 job will also test this
- Replaces the pip-and-virtualenv element with ensure-venv.
  pip-and-virtualenv exists to install virtualenv for python2
  environments, and it is unmaintained and mostly technical debt.

Change-Id: I9b6e03f50a4eb2484a04748e51d7348401b6ca04
(cherry picked from commit 66206d0b27)

dib/ironic-python-agent-ramdisk/element-deps

@@ -3,7 +3,7 @@ dhcp-all-interfaces
 ibft-interfaces
 install-static
 package-installs
-pip-and-virtualenv
+ensure-venv
 pkg-map
 source-repositories
 svc-map

dib/ironic-python-agent-ramdisk/environment.d/20-ipa-distro-family.bash

@@ -1,5 +1,5 @@
 # TODO(dtantsur): verify if opensuse can be added here
-if [[ $DISTRO_NAME =~ (fedora|centos|centos7|rhel|rhel7) ]]; then
+if [[ $DISTRO_NAME =~ (fedora|centos|rhel) ]]; then
     export IPA_DISTRO_FAMILY=rh
 else
     export IPA_DISTRO_FAMILY=other

dib/ironic-python-agent-ramdisk/install.d/ironic-python-agent-ramdisk-source-install/60-ironic-python-agent-ramdisk-install

@@ -13,33 +13,11 @@ IPADIR=/tmp/ironic-python-agent
 IRLIBDIR=/tmp/ironic-lib
 UPPER_CONSTRAINTS=/tmp/requirements/upper-constraints.txt
 VENVDIR=/opt/ironic-python-agent
-# 19.1.1 is required for cryptography.
-REQUIRED_PIP_STR="19.1.1"
-REQUIRED_PIP_TUPLE="(19, 1, 1)"
-
-IPA_PYTHON_VERSION=$DIB_PYTHON_VERSION
-IPA_PYTHON="$DIB_PYTHON"
-
-case "$DISTRO_NAME" in
-    centos7|rhel7)
-        # NOTE(dtantsur): C.UTF-8 doesn't seem to exist in CentOS 7
-        export LC_ALL=en_US.UTF-8
-
-        if grep -q 'Python :: 3 :: Only' $IPADIR/setup.cfg; then
-            echo "WARNING: using Python 3 on CentOS 7, this is not recommended"
-            ${YUM:-yum} install -y python3 python3-devel
-            IPA_PYTHON=python3
-            IPA_PYTHON_VERSION=3
-        fi
-        ;;
-esac
 
 # create the virtual environment using the default python
-if [ $IPA_PYTHON_VERSION == 3 ]; then
-  $IPA_PYTHON -m venv $VENVDIR
-else
-  $IPA_PYTHON -m virtualenv $VENVDIR
-fi
+python3 -m venv $VENVDIR
+REQUIRED_PIP_STR="21.3.1"
+REQUIRED_PIP_TUPLE="(21, 3, 1)"
 
 HAS_PIP=$($VENVDIR/bin/python -c \
     "import pip; print(tuple(map(int, pip.__version__.split('.'))) >= $REQUIRED_PIP_TUPLE)")
@@ -52,7 +30,7 @@ fi
 # NOTE(rpittau): if we want to keep compatibility with Python 2.x, we need to
 # upgrade setuptools in the virtualenv as the default installed has issues
 # when parsing requirements.
-if [ "$DISTRO_NAME" == "opensuse" ] || [ $IPA_PYTHON_VERSION == 2 ]; then
+if [ "$DISTRO_NAME" == "opensuse" ]; then
     $VENVDIR/bin/pip install -U setuptools
 fi
 

dib/ironic-python-agent-ramdisk/post-install.d/99-remove-extra-packages

@@ -21,7 +21,7 @@ done
 
 # TODO(dtantsur): implement the same for debian-based systems
 case "$DISTRO_NAME" in
-    fedora|centos|centos7|rhel|rhel7)
+    fedora|centos|rhel)
         ${YUM:-yum} remove -y postfix gcc make
         ${YUM:-yum} clean all
         # Rebuilding the rpm database after removing packages will reduce

releasenotes/notes/python2-removal-dee895550b1959af.yaml

@@ -0,0 +1,10 @@
+---
+upgrade:
+  - |
+    Support for python2 in ironic-python-agent was dropped in the Ussuri release
+    however it was still possible to build (non-functional) python2 images for
+    CentOS 7. This python2 support is now dropped from the image build also. As
+    part of this change, the `pip-and-virtualenv` element is not longer a
+    dependency, so any custom elements which depend on this element will need to
+    either include it explicitly or migrate to the recommended `ensure-venv`
+    element.

zuul.d/ironic-python-agent-builder-jobs.yaml

@@ -19,16 +19,6 @@
     vars:
       image_type: 'tinyipa'
 
-- job:
-    name: ironic-python-agent-build-image-dib-centos7
-    parent: ironic-python-agent-build-image-base
-    override-branch: stable/train
-    required-projects:
-      - openstack/diskimage-builder
-    vars:
-      image_type: 'dib'
-      image_distro: 'centos7'
-
 - job:
     name: ironic-python-agent-build-image-dib-centos8
     parent: ironic-python-agent-build-image-base
@@ -78,16 +68,6 @@
     vars:
       image_type: 'tinyipa'
 
-- job:
-    name: ironic-python-agent-check-image-dib-centos7
-    parent: ironic-python-agent-check-image-base
-    override-branch: stable/train
-    required-projects:
-      - openstack/diskimage-builder
-    vars:
-      image_type: 'dib'
-      image_distro: 'centos7'
-
 - job:
     name: ironic-python-agent-check-image-dib-centos7-python3
     parent: ironic-python-agent-check-image-base

zuul.d/project.yaml

@@ -11,12 +11,10 @@
         - ironic-python-agent-check-image-tinyipa
         - ironic-python-agent-check-image-dib-centos8
         - ironic-python-agent-check-image-dib-centos8-extra
-        - ironic-python-agent-check-image-dib-centos7
+        - ironic-python-agent-check-image-dib-centos7-python3
         - ironic-python-agent-check-image-dib-debian
         - ironic-python-agent-check-image-dib-debian-extra
         # Non-voting jobs
-        - ironic-python-agent-check-image-dib-centos7-python3:
-            voting: false
         - ironic-python-agent-check-image-dib-ubuntu:
             voting: false
         - ironic-python-agent-check-image-dib-opensuse:
@@ -37,7 +35,7 @@
         - ironic-python-agent-check-image-tinyipa
         - ironic-python-agent-check-image-dib-centos8
         - ironic-python-agent-check-image-dib-centos8-extra
-        - ironic-python-agent-check-image-dib-centos7
+        - ironic-python-agent-check-image-dib-centos7-python3
         - ironic-python-agent-check-image-dib-debian
         - ironic-python-agent-check-image-dib-debian-extra
     post: