Deprecate dib-python; remove from in-tree elements

We are at the point that all distributions we are building have Python
3, so any tools running in the chroot can assume Python 3 exists.
This makes dib-python redundant; mark it as deprecated and start to
remove it from elements where it is no longer required.

Change-Id: I5d852843ec65d3b04444b77c54c5b82424455cd8

diskimage_builder/elements/debian-minimal/element-deps

@@ -1,3 +1,2 @@
 debootstrap
-dib-python
 pkg-map

diskimage_builder/elements/debian-minimal/root.d/75-debian-minimal-baseinstall

@@ -73,13 +73,6 @@ to_install+="busybox sudo "
 # required for dpkg element to be able to add apt keys
 to_install+="gnupg2 "
 
-if [ "$DIB_PYTHON_VERSION" == "2" ]; then
-    to_install+="python "
-elif [ "$DIB_PYTHON_VERSION" == "3" ]; then
 to_install+="python3 "
-else
-    echo "ERROR: DIB_PYTHON_VERSION is '$DIB_PYTHON_VERSION' but needs to be 2 or 3"
-    exit 1
-fi
 
 $apt_get install -y $to_install

diskimage_builder/elements/dib-python/README.rst

@@ -2,6 +2,11 @@
 dib-python
 ==========
 
+.. note::
+
+   This element is deprecated.  All distributions support Python 3 so
+   tools running in the chroot can simply use ``/usr/bin/python3``.
+
 Adds a symlink to ``/usr/local/bin/dib-python`` which points at either a
 ``python2`` or ``python3`` executable as appropriate.
 

diskimage_builder/elements/dracut-regenerate/finalise.d/50-dracut-regenerate

@@ -1,4 +1,4 @@
-#!/usr/local/bin/dib-python
+#!/usr/bin/env python3
 
 # Copyright 2017 Red Hat, Inc.
 #

diskimage_builder/elements/package-installs/bin/package-installs-v2

@@ -1,4 +1,4 @@
-#!/usr/local/bin/dib-python
+#!/usr/bin/env python3
 
 # Copyright 2014 Hewlett-Packard Development Company, L.P.
 #
@@ -14,8 +14,6 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
-from __future__ import print_function
-
 import argparse
 import json
 import locale

diskimage_builder/elements/package-installs/element-deps

@@ -1,3 +1,2 @@
-dib-python
 install-bin
 pkg-map

diskimage_builder/elements/pkg-map/bin/pkg-map

@@ -1,4 +1,4 @@
-#!/usr/local/bin/dib-python
+#!/usr/bin/env python3
 
 # Copyright 2014 Red Hat Inc.
 #

diskimage_builder/elements/pkg-map/element-deps

@@ -1 +0,0 @@
-dib-python

diskimage_builder/elements/pypi/element-deps

@@ -1 +0,0 @@
-dib-python

diskimage_builder/elements/pypi/pre-install.d/04-configure-pypi-mirror

@@ -1,4 +1,4 @@
-#!/usr/local/bin/dib-python
+#!/usr/bin/env python3
 #
 # Licensed under the Apache License, Version 2.0 (the "License"); you may
 # not use this file except in compliance with the License. You may obtain

diskimage_builder/elements/redhat-common/bin/map-packages

@@ -1,4 +1,4 @@
-#!/usr/local/bin/dib-python
+#!/usr/bin/env python3
 # dib-lint: disable=indent
 # dib-lint indent requirements causes issue with pep8
 
@@ -16,7 +16,6 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
-from __future__ import print_function
 import sys
 
 # Manually maintained for brevity; consider making this compiled from

diskimage_builder/elements/svc-map/bin/svc-map

@@ -1,4 +1,4 @@
-#!/usr/local/bin/dib-python
+#!/usr/bin/env python3
 
 # Copyright 2012 Hewlett-Packard Development Company, L.P.
 # Copyright 2014 Red Hat, Inc.

diskimage_builder/elements/ubuntu-minimal/root.d/75-ubuntu-minimal-baseinstall

@@ -56,17 +56,6 @@ if [ $DIB_RELEASE != "trusty" ] && [ $DIB_RELEASE != "xenial" ]; then
 fi
 
 # default required
-to_install+="busybox sudo " # dib-lint: safe_sudo
-# required for dpkg element to be able to add apt keys
-to_install+="gnupg2 "
-
-if [ "$DIB_PYTHON_VERSION" == "2" ]; then
-    to_install+="python "
-elif [ "$DIB_PYTHON_VERSION" == "3" ]; then
-    to_install+="python3 "
-else
-    echo "ERROR: DIB_PYTHON_VERSION is '$DIB_PYTHON_VERSION' but needs to be 2 or 3"
-    exit 1
-fi
+to_install+="busybox sudo python3 " # dib-lint: safe_sudo
 
 $apt_get install -y $to_install

diskimage_builder/elements/ubuntu-systemd-container/root.d/75-ubuntu-minimal-baseinstall

@@ -51,15 +51,6 @@ if [ $DIB_RELEASE != "trusty" ] && [ $DIB_RELEASE != "xenial" ]; then
 fi
 
 # default required
-to_install+="sudo " # dib-lint: safe_sudo
-
-if [ "$DIB_PYTHON_VERSION" == "2" ]; then
-    to_install+="python "
-elif [ "$DIB_PYTHON_VERSION" == "3" ]; then
-    to_install+="python3 "
-else
-    echo "ERROR: DIB_PYTHON_VERSION is '$DIB_PYTHON_VERSION' but needs to be 2 or 3"
-    exit 1
-fi
+to_install+="sudo python3 " # dib-lint: safe_sudo
 
 $apt_get install -y $to_install

releasenotes/notes/dib-python-deprecate-8401c35a87559076.yaml

@@ -0,0 +1,5 @@
+---
+deprecations:
+  - |
+    The ``dib-python`` element is deprecated.  In chroot Python tools
+    should use ``#!/usrbin/env python3`` on all distributions now.