Revert "Add sphinx_python variable to sphinx role and job"

This reverts commit 1f8c473765.

Change-Id: I98e7414337d58af0f4819163ee0e88702a52c051

roles/ensure-sphinx/README.rst

@@ -16,11 +16,6 @@ All pip installs are done with a provided constraints file, if given.
 
    List of python packages to install for building docs.
 
-.. zuul:rolevar:: sphinx_python
-   :default: python2
-
-   Version of python to use, either ``python2`` or ``python3``.
-
 .. zuul:rolevar:: zuul_work_virtualenv
    :default: ~/.venv
 

roles/ensure-sphinx/defaults/main.yaml

@@ -1,5 +1,4 @@
 zuul_work_dir: "{{ zuul.project.src_dir }}"
 zuul_work_virtualenv: "{{ ansible_user_dir }}/.venv"
-sphinx_python: python2
 doc_building_packages:
   - sphinx

roles/ensure-sphinx/tasks/main.yaml

@@ -9,27 +9,36 @@
   include_role:
     name: find-constraints
 
-# Note (dmsimard): This installs doc/requirements.txt or test-requirements.txt
-# if the former is not found. If neither are found, this task is skipped.
-# TODO(dmsimard) Don't assume virtualenv is installed
-- name: Initialize virtual environment
-  pip:
-    requirements: "{{ item }}"
+- name: Install virtualenv and doc requirements files if found
+  shell:
+    executable: /bin/bash
     chdir: "{{ zuul_work_dir }}"
-    virtualenv: "{{ zuul_work_virtualenv }}"
-    virtualenv_python: "{{ sphinx_python }}"
-    extra_args: "{{ upper_constraints | default(omit) }}"
-  with_first_found:
-    - files:
-        - "{{ zuul_work_dir }}/doc/requirements.txt"
-        - "{{ zuul_work_dir }}/test-requirements.txt"
-      skip: true
+    # NOTE(mordred) There is a bug in ansible-lint that mistakenly detects
+    # setting the VENV variable below as an error if it occurs on the fist
+    # line. Work around that by putting a comment as the first line until we
+    # can get a fix upstream.
+    cmd: |
+      # Create virtualenv is it does not already exist
+      VENV={{ zuul_work_virtualenv }}
+      if [ ! -d $VENV ] ; then
+          virtualenv $VENV
+      fi
+      source $VENV/bin/activate
+      # skipping requirements.txt as it gets picked up by installing the
+      # python package itself
+      for f in doc/requirements.txt test-requirements.txt ; do
+          if [ -f $f ] ; then
+              pip install $CONSTRAINTS -r $f
+              break
+          fi
+      done
+  environment:
+    CONSTRAINTS: "{{ upper_constraints|default('') }}"
 
 - name: Install doc building packages
   pip:
     name: "{{ item }}"
     chdir: "{{ zuul_work_dir }}"
     virtualenv: "{{ zuul_work_virtualenv }}"
-    virtualenv_python: "{{ sphinx_python }}"
-    extra_args: "{{ upper_constraints | default(omit) }}"
+    extra_args: "{{ upper_constraints|default(omit) }}"
   with_items: "{{ doc_building_packages }}"