From ae6db7a387f8a2a779c5e9c33830d1f8d8af7971 Mon Sep 17 00:00:00 2001
From: Chris Hoge <chris@openstack.org>
Date: Tue, 12 Feb 2019 21:53:34 +0000
Subject: [PATCH] Fix broken symlinks from virtualenv 16.4.0 update

The virtualenv 16.4.0 updates fixes the handling of creating
symlinks of libraries to existing installations. Previously,
virtualenv would copy existing libraries into the virtualenv
making nested environments possible without retaining the
"parent" virtualenv. Now virtualenv builds a symlink chain,
which means we need to preserve the bootstrap virtualenv that
gives us an up-to-date installation of pip and virtualenv.

As distributions update their default virtualenv installations,
we might be able to use the --always-copy flag to stop using
symlinks and just copy dependencies over directly. However, the
virtualenv that ships with CentOS has a bug that causes the use
of that flag to fail, meaning as of right now we can't use it
to boostrap pip.

This patch moves the boostrap virtualenv from /tmp/venv, where
it is deleted in the build process, to /var/lib/pipboostrap,
where the symlink chain from

/var/lib/openstack -> /var/lib/pipbootstrap -> /usr/lib

will be remain unbroken.

Change-Id: I99124c2cfeb6ba7468a034ab510071eb67d98d66
---
 scripts/setup_pip.sh | 28 ++++++++++++++++++++++------
 1 file changed, 22 insertions(+), 6 deletions(-)

diff --git a/scripts/setup_pip.sh b/scripts/setup_pip.sh
index 292d748..6edc367 100755
--- a/scripts/setup_pip.sh
+++ b/scripts/setup_pip.sh
@@ -2,6 +2,7 @@
 
 set -ex
 
+
 if [[ "${PYTHON3}" == "no" ]]; then
     TMP_VIRTUALENV="virtualenv"
 else
@@ -13,12 +14,27 @@ fi
 if (( $(${TMP_VIRTUALENV} --version | cut -d. -f1) >= 14 )); then
     SETUPTOOLS="--no-setuptools"
 fi
-${TMP_VIRTUALENV} --extra-search-dir=/tmp/wheels ${SETUPTOOLS} /tmp/venv
-source /tmp/venv/bin/activate
 
-# TODO: Remove virtualenv version pinning once a suitable fix is found
-# to this issue:
-# http://lists.openstack.org/pipermail/openstack-discuss/2019-February/002592.html
-pip install --upgrade ${PIP_ARGS} virtualenv==16.3.0
+# virtualenv 16.4.0 fixed symlink handling. The interaction of the new
+# corrected behavior with legacy bugs in packaged virtualenv releases in
+# distributions means we need to hold on to the pip bootstrap installation
+# chain to preserve symlinks. As distributions upgrade their default
+# installations we may not need this workaround in the future
+PIPBOOTSTRAP=/var/lib/pipbootstrap
+
+# Create the boostrap environment so we can get pip from virtualenv
+${TMP_VIRTUALENV} --extra-search-dir=/tmp/wheels ${SETUPTOOLS} ${PIPBOOTSTRAP}
+source ${PIPBOOTSTRAP}/bin/activate
+
+# Upgrade to the latest version of virtualenv
+pip install --upgrade ${PIP_ARGS} virtualenv
+
+# Forget the cached locations of python binaries
 hash -r
+
+# Create the virtualenv with the updated toolchain for openstack service
 virtualenv --extra-search-dir=/tmp/wheels /var/lib/openstack
+
+# Deactivate the old bootstrap virtualenv and switch to the new one
+deactivate
+source /var/lib/openstack/bin/activate