Check openstack kuryr prerequisites

In order to fail gracefully we must detect when Neutron is not
configured in the way Kuryr needs.

Change-Id: I2c07ddc864b8622b958f18b4808f9d96f3906532
Signed-off-by: Antoni Segura Puimedon <antonisp@celebdor.com>

roles/openshift_openstack/library/os_network_extensions.py

@@ -0,0 +1,101 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+
+# Copyright 2018 Red Hat, Inc. and/or its affiliates
+# and other contributors as indicated by the @author tags.
+#
+# 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.
+
+
+# pylint: disable=unused-wildcard-import,wildcard-import,unused-import,redefined-builtin
+
+''' os_network_extensions '''
+
+from ansible.module_utils.basic import AnsibleModule
+import keystoneauth1
+
+try:
+    import shade
+    HAS_SHADE = True
+except ImportError:
+    HAS_SHADE = False
+
+DOCUMENTATION = '''
+---
+module: os_network_extensions_facts
+short_description: Retrieve OpenStack Networking extension facts
+description:
+    - Retrieves all the OpenStack Neutron available extensions
+notes:
+    - This module creates a new top-level C(openstack_network_extensions) fact
+      which contains a list of supported OpenStack Neutron extensions
+author:
+    - "Antoni Segura Puimedon <antoni@redhat.com>"
+'''
+
+RETURN = '''
+openstack_network_extensions:
+    description: List of available extensions in the Cloud Neutron
+    type: list
+    returned: always
+    sample:
+      - agent
+      - router
+      - subnet_allocation
+      - trunk
+'''
+
+
+def main():
+    ''' Main module function '''
+    module = AnsibleModule(argument_spec={}, supports_check_mode=True)
+
+    if not HAS_SHADE:
+        module.fail_json(msg='shade is required for this module')
+
+    try:
+        cloud = shade.openstack_cloud()
+    except Exception:
+        module.fail_json(msg='Failed to connect to the cloud')
+
+    try:
+        adapter = keystoneauth1.adapter.Adapter(
+            session=cloud.keystone_session,
+            service_type=cloud.cloud_config.get_service_type('network'),
+            interface=cloud.cloud_config.get_interface('network'),
+            endpoint_override=cloud.cloud_config.get_endpoint('network'),
+            version=cloud.cloud_config.get_api_version('network'))
+    except Exception:
+        module.fail_json(msg='Failed to get an adapter to talk to the Neutron '
+                             'API')
+
+    try:
+        response = adapter.get('/extensions.json')
+    except Exception:
+        module.fail_json(msg='Failed to retrieve Neutron extensions')
+
+    extensions = []
+    try:
+        for ext_record in response.json()['extensions']:
+            extensions.append(ext_record['alias'])
+    except Exception:
+        module.fail_json(msg='Failed to process cloud networking '
+                         'extensions')
+
+    module.exit_json(
+        changed=False,
+        ansible_facts={'openstack_network_extensions': extensions})
+
+
+if __name__ == '__main__':
+    main()

roles/openshift_openstack/tasks/check-prerequisites.yml

@@ -17,6 +17,22 @@
     that: 'shade_result.rc == 0'
     msg: "Python module shade is not installed"
 
+# Gather Neutron extension facts
+- name: Check for Neutron trunk support
+  os_network_extensions:
+
+# Check trunk support
+- fail:
+    msg: "Trunk ports enabled but support lacking in Neutron"
+  when: (use_trunk_ports | default(False)) and
+        ('trunk' not in openstack_network_extensions)
+
+# Check lbaasv2 support
+- fail:
+    msg: "Kuryr enabled but lacking required lbaasv2 support in Neutron"
+  when: (openshift_use_kuryr | default(False)) and
+        ('lbaasv2' not in openstack_network_extensions)
+
 # Check jmespath
 - name: Try to import python module shade
   command: python -c "import jmespath"