[ansible] fix wwn facts and root device hints

Apparently only checking that pyudev is importable is not enough,
as it can fail later if udev itself is not available on the system

Also bring the (empty) default between these two to be empty dict,
and fix logging invocations in WWN fact collecting module.

Change-Id: I137990280e90c9ca2687b38d98f6c5343e26e8d0

ironic_staging_drivers/ansible/playbooks/library/facts_wwn.py

@@ -1,4 +1,3 @@
-#!/usr/bin/python
 # -*- coding: utf-8 -*-
 #
 # Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -13,36 +12,33 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
-try:
-    import pyudev
-    HAS_PYUDEV = True
-except ImportError:
-    HAS_PYUDEV = False
-
-
 COLLECT_INFO = (('wwn', 'WWN'), ('serial', 'SERIAL_SHORT'),
                 ('wwn_with_extension', 'WWN_WITH_EXTENSION'),
                 ('wwn_vendor_extension', 'WWN_VENDOR_EXTENSION'))
 
 
-def get_devices_wwn(devices):
-
-    if not HAS_PYUDEV:
-        LOG.warning('Can not collect "wwn", "wwn_with_extension", '
-                    '"wwn_vendor_extension" and "serial" when using '
-                    'root device hints because there\'s no UDEV python '
-                    'binds installed')
-        return
+# TODO(pas-ha) replace module.log with module.warn
+# after we require Ansible >= 2.3
+def get_devices_wwn(devices, module):
+    try:
+        import pyudev
+        # NOTE(pas-ha) creating context might fail if udev is missing
+        context = pyudev.Context()
+    except ImportError:
+        module.log('Can not collect "wwn", "wwn_with_extension", '
+                   '"wwn_vendor_extension" and "serial" when using '
+                   'root device hints because there\'s no UDEV python '
+                   'binds installed')
+        return {}
 
     dev_dict = {}
-    context = pyudev.Context()
     for device in devices:
         name = '/dev/' + device
         try:
             udev = pyudev.Device.from_device_file(context, name)
         except (ValueError, EnvironmentError, pyudev.DeviceNotFoundError) as e:
-            LOG.warning('Device %(dev)s is inaccessible, skipping... '
-                        'Error: %(error)s', {'dev': name, 'error': e})
+            module.log('Device %(dev)s is inaccessible, skipping... '
+                       'Error: %(error)s', {'dev': name, 'error': e})
             continue
 
         dev_dict[device] = {}
@@ -61,7 +57,7 @@ def main():
     )
 
     devices = module.params['devices']
-    data = get_devices_wwn(devices)
+    data = get_devices_wwn(devices, module)
     module.exit_json(**data)
 
 

ironic_staging_drivers/ansible/playbooks/library/root_hints.py

@@ -1,4 +1,3 @@
-#!/usr/bin/python
 # -*- coding: utf-8 -*-
 #
 # Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -74,7 +73,7 @@ def main():
     devices = module.params['ansible_devices']
     devices_wwn = module.params['ansible_devices_wwn']
 
-    if devices_wwn is None:
+    if not devices_wwn:
         extra = set(hints) & EXTRA_PARAMS
         if extra:
             module.fail_json(msg='Extra hints (supported by additional ansible'

ironic_staging_drivers/ansible/playbooks/roles/discover/tasks/roothints.yaml

@@ -1,8 +1,9 @@
 - name: get devices wwn facts
   facts_wwn:
     devices: "{{ ansible_devices.keys() }}"
+
 - name: calculate root hint
   root_hints:
     root_device_hints: "{{ ironic.root_device_hints }}"
     ansible_devices: "{{ ansible_devices }}"
-    ansible_devices_wwn: "{{ devices_wwn | default(None) }}"
+    ansible_devices_wwn: "{{ devices_wwn | default({}) }}"