Replace virtualenv-tools with a script

virtualenv-tools has a bug which gets triggered in gates: it can't
change the shebang of a virtualenv python bin/ files if they
were generated with a virtualenv script whose shebang ends with
python2 instead of python.

Because we can't modify virtualenv-tools, we use shell scripts
instead.

Change-Id: I62ae0b1f406f102fcb184913c5a6de54bb84c4c2
Partial-Bug: #1741634
Partial-Bug: #1764470

defaults/main.yml

@@ -260,7 +260,6 @@ monasca_requires_pip_packages:
   - python-keystoneclient
   - python-monascaclient
   - virtualenv
-  - virtualenv-tools
 
 monasca_pip_packages:
   - cassandra-driver

tasks/monasca_install.yml

@@ -113,7 +113,22 @@
     - ansible_pkg_mgr == 'yum'
     - monasca_get_venv | changed
 
-- name: Update virtualenv path
-  command: >
-    virtualenv-tools --update-path=auto --reinitialize {{ monasca_bin | dirname }}
+# NOTE(odyssey4me):
+# We reinitialize the venv to ensure that the right
+# version of python is in the venv, but we do not
+# want virtualenv to also replace pip, setuptools
+# and wheel so we tell it not to.
+# We do not use --always-copy for CentOS/SuSE due
+# to https://github.com/pypa/virtualenv/issues/565
+- name: Reset virtualenv and update its paths
+  shell: |
+    find {{ monasca_bin }} -name \*.pyc -delete
+    sed -si '1s/^.*python.*$/#!{{ monasca_bin | replace ('/','\/') }}\/python/' {{ monasca_bin }}/*
+    virtualenv {{ monasca_bin | dirname }} \
+        {{ (ansible_pkg_mgr == 'apt') | ternary('--always-copy', '') }} \
+        --no-pip \
+        --no-setuptools \
+        --no-wheel
   when: monasca_get_venv | changed
+  tags:
+    - skip_ansible_lint