From 7a962e9d1cb4c680dcbc7c73c7080c0bd9e90a39 Mon Sep 17 00:00:00 2001
From: Ian Wienand <iwienand@redhat.com>
Date: Wed, 12 Apr 2017 05:49:47 +1000
Subject: [PATCH] Skip python3-virtualenv on <= trusty

If DIB_PYTHON_VERSION is < 3 on the !redhat path, that means we're on
an older platform that may not have python3-virtualenv packages.  Skip
install.

Ensure the order of operations happens by forcing the installs

Also add a note about limited platform support (patches welcome :)

Change-Id: I18412767f0ebf946d557a0a126285369e96af159
---
 .../elements/pip-and-virtualenv/README.rst    |  3 +++
 .../04-install-pip                            | 27 ++++++++++++++-----
 2 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/diskimage_builder/elements/pip-and-virtualenv/README.rst b/diskimage_builder/elements/pip-and-virtualenv/README.rst
index 5217f62ff..bf79ff2f6 100644
--- a/diskimage_builder/elements/pip-and-virtualenv/README.rst
+++ b/diskimage_builder/elements/pip-and-virtualenv/README.rst
@@ -47,6 +47,9 @@ The system will be left in the following state:
 
 (note python3 ``virtualenv`` script is *not* installed, see below)
 
+Source install is supported on limited platforms.  See the code, but
+this includes Ubuntu and RedHat platforms.
+
 Using the tools
 ===============
 
diff --git a/diskimage_builder/elements/pip-and-virtualenv/install.d/pip-and-virtualenv-source-install/04-install-pip b/diskimage_builder/elements/pip-and-virtualenv/install.d/pip-and-virtualenv-source-install/04-install-pip
index 932c8031a..1f368b2dd 100755
--- a/diskimage_builder/elements/pip-and-virtualenv/install.d/pip-and-virtualenv-source-install/04-install-pip
+++ b/diskimage_builder/elements/pip-and-virtualenv/install.d/pip-and-virtualenv-source-install/04-install-pip
@@ -101,15 +101,28 @@ EOF
         echo "exclude=$packages" >> ${conf}
     fi
 else
-    # pre-install packages, we will overwrite with latest below
-    apt-get -y install python-pip python3-pip \
-            python-virtualenv python3-virtualenv
+    # pre-install packages so depedencies are there.  We will
+    # overwrite with latest below.
+    packages="python-pip python3-pip python-virtualenv"
+    # unfortunately older ubuntu (trusty) doesn't have a
+    # python3-virtualenv package -- it seems it wasn't ready at the
+    # time and you had to use "python -m venv".  Since then virtualenv
+    # has gained 3.4 support so the pip install below will work
+    if [[ ${DIB_PYTHON_VERSION} == 3 ]]; then
+        packages+=" python3-virtualenv"
+    fi
+
+    apt-get -y install $packages
+
+    # force things to happen so our assumptions hold
+    pip_args="-U --force-reinstall"
 
     # These install into /usr/local/bin so override any packages, even
     # if installed later.
-    python3 /tmp/get-pip.py
-    python2 /tmp/get-pip.py
 
-    pip3 install virtualenv
-    pip install virtualenv
+    python3 /tmp/get-pip.py $pip_args
+    python2 /tmp/get-pip.py $pip_args
+
+    pip3 install $pip_args virtualenv
+    pip install $pip_args virtualenv
 fi