testinfra: pass inventory and zuul data

Create a zuul_data fixture for testinfra.

The fixture directly loads the inventory from the inventory YAML file
written out.  This lets you get easy access to the IP addresses of the
hosts.

We pass in the "zuul" variable by writing it out to a YAML file on
disk, and then passing an environment variable to this.  This is
useful for things like determining which job is running.  Additional
arbitrary data could be added to this if required.

Change-Id: I8adb7601f7eec6d48509f8f1a42840beca70120c

playbooks/zuul/run-base.yaml

@@ -110,6 +110,18 @@
     - name: Run test playbook
       when: run_test_playbook is defined
       shell: "ANSIBLE_ROLES_PATH=/home/zuul/src/opendev.org/opendev/system-config/playbooks/roles ansible-playbook -v /home/zuul/src/opendev.org/opendev/system-config/{{ run_test_playbook }}"
+
+    - name: Generate testinfra extra data fixture
+      set_fact:
+        testinfra_extra_data:
+          zuul_job: '{{ zuul.job }}'
+          zuul: '{{ zuul }}'
+
+    - name: Write out testinfra extra data fixture
+      copy:
+        content: '{{ testinfra_extra_data | to_nice_yaml }}'
+        dest: '/home/zuul/testinfra_extra_data_fixture.yaml'
+
     - name: Run testinfra to validate configuration
       include_role:
         name: tox
@@ -117,4 +129,6 @@
         tox_envlist: testinfra
         # This allows us to run from external projects (like testinfra
         # itself)
+        tox_environment:
+          TESTINFRA_EXTRA_DATA: '/home/zuul/testinfra_extra_data_fixture.yaml'
         zuul_work_dir: src/opendev.org/opendev/system-config

testinfra/conftest.py

@@ -0,0 +1,20 @@
+import os
+import pytest
+import yaml
+
+@pytest.fixture
+def zuul_data():
+
+    data = {}
+
+    with open('/etc/ansible/hosts/inventory.yaml') as f:
+        inventory = yaml.load(f)
+        data['inventory'] = inventory
+
+    zuul_extra_data_file = os.environ.get('TESTINFRA_EXTRA_DATA')
+    if os.path.exists(zuul_extra_data_file):
+        with open(zuul_extra_data_file, 'r') as f:
+            extra = yaml.load(f)
+            data['extra'] = extra
+
+    return data

testinfra/test_bridge.py

@@ -17,6 +17,13 @@ import pytest
 testinfra_hosts = ['bridge.openstack.org']
 
 
+def test_zuul_data(host, zuul_data):
+    # Test the zuul_data fixture that picks up things set by Zuul
+    assert 'inventory' in zuul_data
+    assert 'extra' in zuul_data
+    assert 'zuul' in zuul_data['extra']
+
+
 def test_clouds_yaml(host):
     clouds_yaml = host.file('/etc/openstack/clouds.yaml')
     assert clouds_yaml.exists

tox.ini

@@ -33,6 +33,8 @@ deps = -r{toxinidir}/doc/requirements.txt
 commands = sphinx-build -W -E -b html doc/source doc/build/html
 
 [testenv:testinfra]
+passenv =
+  TESTINFRA_EXTRA_DATA
 commands = py.test --junit-xml junit.xml --connection=ansible --ansible-inventory=/etc/ansible/hosts/inventory.yaml -v testinfra {posargs}
 
 [flake8]