Set the config ID as an ansible variable

This change sets the ansible variable called heat_config_id to the
'id' value of the heat config data.

This will be useful in some playbooks to make idempotency decisions.

Change-Id: I5f03e012b2fb97cc0076c886ca7bd3f284d19032

heat-config-ansible/install.d/hook-ansible.py

@@ -47,6 +47,7 @@ def main(argv=sys.argv):
     c = json.load(sys.stdin)
 
     variables = {}
+    variables['heat_config_id'] = c['id']
     for input in c['inputs']:
         variables[input['name']] = input.get('value', '')
 

tests/test_hook_ansible.py

@@ -187,6 +187,7 @@ class HookAnsibleTest(common.RunScriptTest):
         variables = self.json_from_file(vars_filename)
         self.assertEqual('bar', variables['foo'])
         self.assertEqual('input', variables['another'])
+        self.assertEqual('1234', variables['heat_config_id'])
         self.assertEqual(self.outputs_dir.join('1234'),
                          variables['heat_outputs_path'])