Start of docker hook unit tests

Other hooks process json then execute commands. The docker hook
makes socket API calls via the docker-py module. For this reason
a different approach has been taken with testing this hook:
- symlink hook-docker.py to the tests package as hook_docker.py
- in the test, mock out the docker import and run main() directly

Change-Id: Ia069b2cc0db71952732dea310a8986b73981b656

hot/software-config/elements/heat-config-docker/install.d/hook-docker.py

@@ -18,7 +18,11 @@ import logging
 import os
 import sys
 
-import docker
+try:
+    import docker
+except ImportError:
+    docker = None
+
 import yaml
 
 
@@ -142,7 +146,7 @@ def update_pod_state(pod_state, is_container_running):
 
 def configure_logging():
     log = logging.getLogger('heat-config')
-    log.setLevel('DEBUG')
+    log.setLevel(logging.DEBUG)
     formatter = logging.Formatter(
         '[%(asctime)s] (%(name)s) [%(levelname)s] %(message)s')
 
@@ -154,23 +158,23 @@ def configure_logging():
     deploy_stdout = cStringIO.StringIO()
     handler = logging.StreamHandler(deploy_stdout)
     handler.setFormatter(formatter)
-    handler.setLevel('DEBUG')
+    handler.setLevel(logging.DEBUG)
     log.addHandler(handler)
 
     deploy_stderr = cStringIO.StringIO()
     handler = logging.StreamHandler(deploy_stderr)
     handler.setFormatter(formatter)
-    handler.setLevel('DEBUG')
+    handler.setLevel(logging.WARN)
     log.addHandler(handler)
 
     return log, deploy_stdout, deploy_stderr
 
 
-def main(argv=sys.argv):
+def main(argv=sys.argv, sys_stdin=sys.stdin, sys_stdout=sys.stdout):
     (log, deploy_stdout, deploy_stderr) = configure_logging()
     client = get_client(log)
 
-    c = json.load(sys.stdin)
+    c = json.load(sys_stdin)
 
     pod_name = c.get('name')
     input_values = dict((i['name'], i['value']) for i in c['inputs'])
@@ -182,8 +186,8 @@ def main(argv=sys.argv):
     else:
         yaml_config = yaml.load(config)
 
-    containers = yaml_config.get('containers')
-    volumes = yaml_config.get('volumes')
+    containers = yaml_config.get('containers', [])
+    volumes = yaml_config.get('volumes', [])
 
     remove_all_containers_for_pod(client, log, pod_name)
 
@@ -196,7 +200,7 @@ def main(argv=sys.argv):
             'deploy_stderr': deploy_stderr.getvalue(),
             'deploy_status_code': 0,
         }
-        json.dump(response, sys.stdout)
+        json.dump(response, sys_stdout)
         return
 
     mount_external_volumes(log, volumes)
@@ -260,7 +264,7 @@ def main(argv=sys.argv):
         'deploy_stderr': deploy_stderr.getvalue(),
         'deploy_status_code': pod_state,
     }
-    json.dump(response, sys.stdout)
+    json.dump(response, sys_stdout)
 
 
 if __name__ == '__main__':

tests/software_config/hook_docker.py

@@ -0,0 +1 @@
+../../hot/software-config/elements/heat-config-docker/install.d/hook-docker.py

tests/software_config/test_hook_docker.py

@@ -0,0 +1,63 @@
+#
+#    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 cStringIO
+import json
+import mock
+import testtools
+from testtools import matchers
+
+from tests.software_config import hook_docker
+
+
+class HookDockerTest(testtools.TestCase):
+
+    def setUp(self):
+        super(HookDockerTest, self).setUp()
+        docker = mock.MagicMock()
+        self.docker_client = mock.MagicMock()
+        docker.Client.return_value = self.docker_client
+        self.docker_client.version.return_value = {
+            'ApiVersion': '1.3.0'
+        }
+        hook_docker.docker = docker
+
+    def assertLogEntries(self, entries, log):
+        for (entry, line) in zip(entries, log.split('\n')):
+            self.assertThat(line, matchers.EndsWith(entry))
+
+    def test_empty_input(self):
+        config = {
+            'name': 'deployment_name',
+            'options': {},
+            'inputs': [],
+            'outputs': [],
+            'config': {}
+        }
+        sys_stdin = cStringIO.StringIO(json.dumps(config))
+        sys_stdout = cStringIO.StringIO()
+        hook_docker.main([], sys_stdin, sys_stdout)
+
+        response = json.loads(sys_stdout.getvalue())
+
+        self.assertLogEntries([
+            'Connecting to unix:///var/run/docker.sock',
+            'Connected to version 1.3.0',
+            'Removing all containers from deployment_name'
+        ], response.pop('deploy_stdout'))
+
+        self.assertLogEntries([], response.pop('deploy_stderr'))
+
+        self.assertEqual(
+            {"deploy_status_code": 0}, response)