Creating OS clients from the environment variables

Use `osclients.Clients.create_from_env' to create a Clients instance
from the environment variables. Useful for trying things in a Python
shell.

Change-Id: I807176183ff692f15b8700a8db1d0c231af3f5c6

rally/osclients.py

@@ -13,6 +13,8 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+import os
+
 from ceilometerclient import client as ceilometer
 from cinderclient import client as cinder
 from designateclient import v1 as designate
@@ -33,6 +35,7 @@ from zaqarclient.queues import client as zaqar
 from rally.common import log as logging
 from rally import consts
 from rally import exceptions
+from rally import objects
 
 
 CONF = cfg.CONF
@@ -85,6 +88,17 @@ class Clients(object):
         self.endpoint = endpoint
         self.cache = {}
 
+    @classmethod
+    def create_from_env(cls):
+        return cls(
+            objects.Endpoint(
+                os.environ["OS_AUTH_URL"],
+                os.environ["OS_USERNAME"],
+                os.environ["OS_PASSWORD"],
+                os.environ.get("OS_TENANT_NAME"),
+                region_name=os.environ.get("OS_REGION_NAME")
+            ))
+
     def clear(self):
         """Remove all cached client handles."""
         self.cache = {}

tests/unit/test_osclients.py

@@ -47,6 +47,21 @@ class OSClientsTestCase(test.TestCase):
     def tearDown(self):
         super(OSClientsTestCase, self).tearDown()
 
+    def test_create_from_env(self):
+        with mock.patch.dict("os.environ",
+                             {"OS_AUTH_URL": "foo_auth_url",
+                              "OS_USERNAME": "foo_username",
+                              "OS_PASSWORD": "foo_password",
+                              "OS_TENANT_NAME": "foo_tenant_name",
+                              "OS_REGION_NAME": "foo_region_name"}):
+            clients = osclients.Clients.create_from_env()
+
+        self.assertEqual("foo_auth_url", clients.endpoint.auth_url)
+        self.assertEqual("foo_username", clients.endpoint.username)
+        self.assertEqual("foo_password", clients.endpoint.password)
+        self.assertEqual("foo_tenant_name", clients.endpoint.tenant_name)
+        self.assertEqual("foo_region_name", clients.endpoint.region_name)
+
     def test_keystone(self):
         self.assertNotIn("keystone", self.clients.cache)
         client = self.clients.keystone()