Fix for PEP517 issue with Python 3.6.8

When creating a virtualenv with Python 3.6.8 using the
--system-site-packages option and pip>=19.0.0 a bug affects
the virtualenv breaking pep build isolation.
This patch downgrade pip to version 19.0.0 as a
workaround.

Also converts pip3 command to pip.

See [1] for more info.

[1] https://github.com/pypa/pip/issues/6264

Change-Id: I738d7c2e50914a773920e5381305e8c5131ccd5f

playbooks/roles/bifrost-ironic-install/defaults/main.yml

@@ -309,7 +309,7 @@ ironic_inspector:
     # DEPRECATED(TheJulia): Inheritance of ironic_db_password params
     # should be removed in Queens.
 
-pip_opts: "--upgrade-strategy only-if-needed"
+pip_opts: "{{ lookup('env', 'PIP_OPTS') | default('') }}"
 
 # Timeout for gathering facts.
 fact_gather_timeout: "{{ lookup('config', 'DEFAULT_GATHER_TIMEOUT', on_missing='skip') | default(omit, true) }}"

playbooks/roles/bifrost-ironic-install/tasks/pip_install.yml

@@ -19,6 +19,11 @@
     venv_command: "python3 -m venv"
   when: enable_venv
 
+- name: workaround for PEP517 issue
+  set_fact:
+    extra_args: ""
+  when: ansible_python_version == "3.6.8"
+
 - name: Set extra_args if upper_constraints_file is defined
   set_fact:
     constraints_extra_args: "{{ extra_args | default('') }} -c {{ upper_constraints_file }}"
@@ -57,12 +62,10 @@
   delay: 10
   when: (source_install is not defined or source_install | bool == false ) and enable_venv | default(false) | bool == false
 
-# NOTE (cinerama): We should be able to use the pip module here
 - name: "Install requirements from {{ sourcedir }} using pip"
-  command: |
-      pip3 install -r {{ sourcedir }}/requirements.txt
-      {{ extra_args | default('') }}
-      {% if upper_constraints_file %}-c {{ upper_constraints_file }}{% endif %}
+  pip:
+    extra_args: "{{ extra_args | default('') }} {% if upper_constraints_file %}-c {{ upper_constraints_file }}{% endif %}"
+    requirements: "{{ sourcedir }}/requirements.txt"
   register: pip_package_install_done
   until: pip_package_install_done is succeeded
   retries: 5

playbooks/roles/bifrost-keystone-install/defaults/main.yml

@@ -61,4 +61,4 @@ keystone:
     password: ChangeThisPa55w0rd
     host: localhost
 
-pip_opts: "--upgrade-strategy only-if-needed"
+pip_opts: "{{ lookup('env', 'PIP_OPTS') | default('') }}"

scripts/install-deps.sh

@@ -156,7 +156,17 @@ PYTHON=$(which python3)
 # requests, one of our indirect dependencies (bug 1459947).
 #
 ls $PYTHON
-sudo -H -E $PYTHON -m pip install -U pip --ignore-installed
+
+# workaround for PEP517 issue
+PYTHON_VER=$($PYTHON -V)
+if [[ $PYTHON_VER == "Python 3.6.8" ]]; then
+    sudo -H -E $PYTHON -m pip install pip==19.0 --ignore-installed
+    export PIP_OPTS=""
+else
+    sudo -H -E $PYTHON -m pip install -U pip --ignore-installed
+    export PIP_OPTS="--upgrade-strategy only-if-needed"
+fi
+
 if [ "$?" != "0" ]; then
     wget -O /tmp/get-pip.py https://bootstrap.pypa.io/3.4/get-pip.py
     sudo -H -E ${PYTHON} /tmp/get-pip.py