Adds tripleo-repos molecule test job

Adds local method for testing the validity of the modified roles via
molecule on supported platforms.

This change is adding a pytest that calls molecule to validate
tripleo-repos role on supported platforms.

On CI this change uses a local docker installation but if the developer
wants, (s)he can just define a DOCKER_HOST=ssh://user@server variable
to enable remote execution of the containers (tested).

Change-Id: I2acecc16064b3f155de3e82368c64b060304a5e2
Story: https://tree.taiga.io/project/tripleo-ci-board/us/805
Depends-On: https://review.opendev.org/#/c/663599/

roles/tripleo-repos/molecule/Dockerfile.j2

@@ -0,0 +1,21 @@
+# Molecule managed
+
+{% if item.registry is defined %}
+FROM {{ item.registry.url }}/{{ item.image }}
+{% else %}
+FROM {{ item.image }}
+{% endif %}
+
+RUN if [ $(command -v apt-get) ]; then apt-get update && apt-get install -y python sudo bash ca-certificates && apt-get clean; \
+    elif [ $(command -v dnf) ]; then dnf makecache && dnf --assumeyes install python sudo python-devel python*-dnf bash {{ item.pkg_extras | default('') }} && dnf clean all; \
+    elif [ $(command -v yum) ]; then yum makecache fast && yum install -y python sudo yum-plugin-ovl python-setuptools bash {{ item.pkg_extras | default('') }} && sed -i 's/plugins=0/plugins=1/g' /etc/yum.conf && yum clean all; \
+    elif [ $(command -v zypper) ]; then zypper refresh && zypper install -y python sudo bash python-xml {{ item.pkg_extras | default('') }} && zypper clean -a; \
+    elif [ $(command -v apk) ]; then apk update && apk add --no-cache python sudo bash ca-certificates {{ item.pkg_extras | default('') }}; \
+    elif [ $(command -v xbps-install) ]; then xbps-install -Syu && xbps-install -y python sudo bash ca-certificates {{ item.pkg_extras | default('') }} && xbps-remove -O; fi
+
+{% for pkg in item.easy_install | default([]) %}
+# install pip for centos where there is no python-pip rpm in default repos
+RUN easy_install {{ pkg }}
+{% endfor %}
+
+CMD ["sh", "-c", "while true; do sleep 10000; done"]

roles/tripleo-repos/molecule/default/molecule.yml

@@ -0,0 +1,37 @@
+---
+driver:
+  name: docker
+log: true
+platforms:
+
+  - name: centos7-master
+    hostname: centos7-master
+    image: centos:7
+    dockerfile: ../Dockerfile.j2
+    pkg_extras: python-setuptools
+    easy_install: [pip]
+    environment: &env
+      http_proxy: "{{ lookup('env', 'http_proxy') }}"
+      https_proxy: "{{ lookup('env', 'https_proxy') }}"
+
+  - name: fedora28-master
+    hostname: fedora28-master
+    image: fedora:28
+    dockerfile: ../Dockerfile.j2
+    pkg_extras: python*-setuptools
+    environment:
+      <<: *env
+
+provisioner:
+  name: ansible
+  env:
+    ANSIBLE_STDOUT_CALLBACK: yaml
+    ANSIBLE_VERBOSITY: "2"
+scenario:
+  test_sequence:
+    - destroy
+    - create
+    - converge
+    - destroy
+lint:
+  enabled: false

roles/tripleo-repos/molecule/default/playbook.yml

@@ -0,0 +1,14 @@
+---
+
+- name: Converge
+  hosts: all
+  tasks:
+
+    - name: import tripleo-repos role
+      include_role:
+        name: tripleo-repos
+
+    - name: validate that we can install openstack-tripleo-common
+      package:
+        name: openstack-tripleo-common
+        state: latest

tests/test_molecule.py

@@ -0,0 +1,51 @@
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+# implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import os
+import pytest
+import subprocess
+
+
+# detect if we have a working docker setup and skip with warning if not
+docker_skip = False
+docker_reason = ''
+try:
+    import docker
+    client = docker.from_env(timeout=5)
+    if not client.ping():
+        raise Exception("Failed to ping docker server.")
+except Exception as e:
+    docker_reason = "Skipping molecule tests due: %s" % e
+    docker_skip = True
+
+
+def pytest_generate_tests(metafunc):
+    # detects all molecule scenarios inside the project
+    matches = []
+    if 'testdata' in metafunc.fixturenames:
+        for role in os.listdir("./roles"):
+            role_path = os.path.abspath('./roles/%s' % role)
+            for _, dirnames, _ in os.walk(role_path + '/molecule'):
+                for scenario in dirnames:
+                    if os.path.isfile('%s/molecule/%s/molecule.yml' %
+                                      (role_path, scenario)):
+                        matches.append([role_path, scenario])
+    metafunc.parametrize('testdata', matches)
+
+
+@pytest.mark.skipif(docker_skip, reason=docker_reason)
+def test_molecule(testdata):
+    cwd, scenario = testdata
+    cmd = ['python', '-m', 'molecule', 'test', '-s', scenario]
+    print("running: %s (from %s)" % (" " .join(cmd), cwd))
+    r = subprocess.call(cmd, cwd=cwd)
+    assert r == 0

tox.ini

@@ -1,6 +1,6 @@
 [tox]
 # keep py3 before py2 to assure they are preffered for envs like linters:
-envlist = linters,py{37,36,35,27}
+envlist = linters,py{37,36,35,27},mol
 minversion = 3.4.0
 ignore_basepython_conflict = True
 skip_missing_interpreters = True
@@ -8,10 +8,23 @@ skip_missing_interpreters = True
 [testenv]
 usedevelop = True
 setenv =
+    ANSIBLE_FORCE_COLOR=1
+    ANSIBLE_INVENTORY={toxinidir}/test/hosts.ini
+    ANSIBLE_NOCOWS=1
+    ANSIBLE_RETRY_FILES_ENABLED=0
+    ANSIBLE_STDOUT_CALLBACK=debug
+    PY_COLORS=1
     VIRTUAL_ENV={envdir}
     # Avoid 2020-01-01 warnings: https://github.com/pypa/pip/issues/6207
     PYTHONWARNINGS=ignore:DEPRECATION::pip._internal.cli.base_command
     PIP_DISABLE_PIP_VERSION_CHECK=1
+passenv =
+    ANSIBLE_*
+    DOCKER_*
+    MOLECULE_*
+    SSH_AUTH_SOCK
+    TERM
+
 deps = -r{toxinidir}/test-requirements.txt
        -r{toxinidir}/requirements.txt
 whitelist_externals =
@@ -20,7 +33,7 @@ commands_pre =
     pip install -q bindep
     bindep test
 commands =
-    python -m pytest --html={envlogdir}/reports.html --self-contained-html {posargs:--cov=emit_releases_file}
+    python -m pytest --html={envlogdir}/reports.html --self-contained-html {posargs:--cov=emit_releases_file} scripts
 
 [testenv:venv]
 commands = {posargs}
@@ -36,6 +49,17 @@ whitelist_externals = {[testenv]whitelist_externals}
 commands = {[testenv:linters]commands}
 
 [testenv:cireport]
-passenv =
-  SSH_AUTH_SOCK
 commands = python scripts/tripleo-jobs-gerrit.py {posargs}
+
+[testenv:molecule]
+deps =
+    ansi2html  # GPL (soft-dependency of pytest-html)
+    docker>=3.7  # Apache
+    molecule>=2.22rc1  # MIT
+    paramiko>=2.5.0  # LGPL (soft-dependency of docker that enables ssh protocol)
+    pytest  # MIT
+    pytest-cov  # MIT
+    pytest-html  # MPL 2.0
+    pytest-xdist  # MIT
+commands =
+    python -m pytest -ra --html={envlogdir}/reports.html --self-contained-html {tty:-s} {posargs} tests

zuul.d/layout.yaml

@@ -14,6 +14,7 @@
       - tripleo-standalone-scenarios-full
       - tripleo-undercloud-jobs
       - tripleo-periodic
+      - openstack-tox-molecule
     check:
       jobs:
         - openstack-tox-linters