Use domain env variables as defaults

Use OS_USER_DOMAIN_NAME and OS_PROJECT_DOMAIN_NAME
env variables as the defaults for keystone v3 in
integration tests.

Change-Id: Idb58431cf95988a91504ccac5116e0f8e339578f
Closes-Bug: #1560032
diff --git a/common/clients.py b/common/clients.py
index acbf239..8913595 100644
--- a/common/clients.py
+++ b/common/clients.py
@@ -110,7 +110,8 @@
                 password=self.conf.password)
 
     def _get_identity_client(self):
-        domain = self.conf.domain_name
+        user_domain_name = self.conf.user_domain_name
+        project_domain_name = self.conf.project_domain_name
         kwargs = {
             'username': self.conf.username,
             'password': self.conf.password,
@@ -120,8 +121,8 @@
         # keystone v2 can't ignore domain details
         if self.auth_version == '3':
             kwargs.update({
-                'project_domain_name': domain,
-                'user_domain_name': domain})
+                'user_domain_name': user_domain_name,
+                'project_domain_name': project_domain_name})
         auth = password.Password(**kwargs)
         if self.insecure:
             verify_cert = False
@@ -196,7 +197,8 @@
         return swift_client.Connection(**args)
 
     def _get_metering_client(self):
-        domain = self.conf.domain_name
+        user_domain_name = self.conf.user_domain_name
+        project_domain_name = self.conf.project_domain_name
         try:
             endpoint = self.identity_client.get_endpoint_url('metering',
                                                              self.conf.region)
@@ -218,8 +220,8 @@
             # v2 auth_url
             if self.auth_version == '3':
                 args.update(
-                    {'user_domain_name': domain,
-                     'project_domain_name': domain})
+                    {'user_domain_name': user_domain_name,
+                     'project_domain_name': project_domain_name})
 
             return ceilometer_client.Client(self.CEILOMETER_VERSION,
                                             endpoint, **args)
diff --git a/common/config.py b/common/config.py
index 3aee48f..e99d034 100644
--- a/common/config.py
+++ b/common/config.py
@@ -38,9 +38,13 @@
     cfg.StrOpt('auth_url',
                default=os.environ.get('OS_AUTH_URL'),
                help="Full URI of the OpenStack Identity API (Keystone)"),
-    cfg.StrOpt('domain_name',
-               default='default',
-               help="User/project domain name, if keystone v3 auth_url"
+    cfg.StrOpt('user_domain_name',
+               default=os.environ.get('OS_USER_DOMAIN_NAME'),
+               help="User domain name, if keystone v3 auth_url"
+                    "is used"),
+    cfg.StrOpt('project_domain_name',
+               default=os.environ.get('OS_PROJECT_DOMAIN_NAME'),
+               help="Project domain name, if keystone v3 auth_url"
                     "is used"),
     cfg.StrOpt('region',
                default=os.environ.get('OS_REGION_NAME'),