Adding lazy loading support for storage default project.

Author: dhermes

gcloud/storage/__init__.py

@@ -45,6 +45,7 @@
 from gcloud.storage._implicit_environ import get_default_bucket
 from gcloud.storage._implicit_environ import get_default_connection
 from gcloud.storage._implicit_environ import get_default_project
+from gcloud.storage._implicit_environ import set_default_project
 from gcloud.storage.api import create_bucket
 from gcloud.storage.api import get_all_buckets
 from gcloud.storage.api import get_bucket
@@ -59,7 +60,6 @@
          'https://www.googleapis.com/auth/devstorage.read_write')
 
 _BUCKET_ENV_VAR_NAME = 'GCLOUD_BUCKET_NAME'
-_PROJECT_ENV_VAR_NAME = 'GCLOUD_PROJECT'
 
 
 def set_default_bucket(bucket=None):
@@ -88,25 +88,6 @@ def set_default_bucket(bucket=None):
         _implicit_environ._DEFAULTS.bucket = bucket
 
 
-def set_default_project(project=None):
-    """Set default bucket name either explicitly or implicitly as fall-back.
-
-    In implicit case, currently only supports enviroment variable but will
-    support App Engine, Compute Engine and other environments in the future.
-
-    Local environment variable used is:
-    - GCLOUD_PROJECT
-
-    :type project: string
-    :param project: Optional. The project name to use as default.
-    """
-    if project is None:
-        project = os.getenv(_PROJECT_ENV_VAR_NAME)
-
-    if project is not None:
-        _implicit_environ._DEFAULTS.project = project
-
-
 def set_default_connection(connection=None):
     """Set default connection either explicitly or implicitly as fall-back.
 

gcloud/storage/_implicit_environ.py

@@ -19,6 +19,55 @@
 """
 
 
+import os
+
+from gcloud._helpers import _lazy_property_deco
+
+
+_PROJECT_ENV_VAR_NAME = 'GCLOUD_PROJECT'
+
+
+def _get_production_project():
+    """Gets the production project if it can be inferred."""
+    return os.getenv(_PROJECT_ENV_VAR_NAME)
+
+
+def _determine_default_project(project=None):
+    """Determine default project ID explicitly or implicitly as fall-back.
+
+    In implicit case, currently only supports enviroment variable but will
+    support App Engine, Compute Engine and other environments in the future.
+
+    Local environment variable used is:
+    - GCLOUD_PROJECT
+
+    :type project: string
+    :param project: Optional. The project name to use as default.
+
+    :rtype: string or ``NoneType``
+    :returns: Default project if it can be determined.
+    """
+    if project is None:
+        project = _get_production_project()
+
+    return project
+
+
+def set_default_project(project=None):
+    """Set default project either explicitly or implicitly as fall-back.
+
+    :type project: string
+    :param project: Optional. The project name to use as default.
+
+    :raises: :class:`EnvironmentError` if no project was found.
+    """
+    project = _determine_default_project(project=project)
+    if project is not None:
+        _DEFAULTS.project = project
+    else:
+        raise EnvironmentError('No project could be inferred.')
+
+
 class _DefaultsContainer(object):
     """Container for defaults.
 
@@ -32,8 +81,16 @@ class _DefaultsContainer(object):
     :param connection: Persistent implied connection from environment.
     """
 
-    def __init__(self, project=None, bucket=None, connection=None):
-        self.project = project
+    @_lazy_property_deco
+    @staticmethod
+    def project():
+        """Return the implicit default project."""
+        return _determine_default_project()
+
+    def __init__(self, project=None, bucket=None, connection=None,
+                 implicit=False):
+        if project is not None or not implicit:
+            self.project = project
         self.bucket = bucket
         self.connection = connection
 
@@ -65,4 +122,4 @@ def get_default_connection():
     return _DEFAULTS.connection
 
 
-_DEFAULTS = _DefaultsContainer()
+_DEFAULTS = _DefaultsContainer(implicit=True)

gcloud/storage/test___init__.py

@@ -135,73 +135,6 @@ def test_set_explicit_None_w_env_var_set(self):
                 self.assertEqual(default_bucket.connection, CONNECTION)
 
 
-class Test_set_default_project(unittest2.TestCase):
-
-    def setUp(self):
-        from gcloud.storage._testing import _setup_defaults
-        _setup_defaults(self)
-
-    def tearDown(self):
-        from gcloud.storage._testing import _tear_down_defaults
-        _tear_down_defaults(self)
-
-    def _callFUT(self, project=None):
-        from gcloud.storage import set_default_project
-        return set_default_project(project=project)
-
-    def _monkey(self, implicit_project):
-        import os
-        from gcloud.storage import _PROJECT_ENV_VAR_NAME
-        from gcloud._testing import _Monkey
-        environ = {_PROJECT_ENV_VAR_NAME: implicit_project}
-        return _Monkey(os, getenv=environ.get)
-
-    def test_no_env_var_set(self):
-        from gcloud.storage import _implicit_environ
-        with self._monkey(None):
-            self._callFUT()
-        self.assertEqual(_implicit_environ.get_default_project(), None)
-
-    def test_set_from_env_var(self):
-        from gcloud.storage import _implicit_environ
-        IMPLICIT_PROJECT = 'IMPLICIT'
-        with self._monkey(IMPLICIT_PROJECT):
-            self._callFUT()
-        self.assertEqual(_implicit_environ.get_default_project(),
-                         IMPLICIT_PROJECT)
-
-    def test_set_explicit_w_env_var_set(self):
-        from gcloud.storage import _implicit_environ
-        EXPLICIT_PROJECT = 'EXPLICIT'
-        with self._monkey(None):
-            self._callFUT(EXPLICIT_PROJECT)
-        self.assertEqual(_implicit_environ.get_default_project(),
-                         EXPLICIT_PROJECT)
-
-    def test_set_explicit_no_env_var_set(self):
-        from gcloud.storage import _implicit_environ
-        IMPLICIT_PROJECT = 'IMPLICIT'
-        EXPLICIT_PROJECT = 'EXPLICIT'
-        with self._monkey(IMPLICIT_PROJECT):
-            self._callFUT(EXPLICIT_PROJECT)
-        self.assertEqual(_implicit_environ.get_default_project(),
-                         EXPLICIT_PROJECT)
-
-    def test_set_explicit_None_wo_env_var_set(self):
-        from gcloud.storage import _implicit_environ
-        with self._monkey(None):
-            self._callFUT(None)
-        self.assertEqual(_implicit_environ.get_default_project(), None)
-
-    def test_set_explicit_None_w_env_var_set(self):
-        from gcloud.storage import _implicit_environ
-        IMPLICIT_PROJECT = 'IMPLICIT'
-        with self._monkey(IMPLICIT_PROJECT):
-            self._callFUT(None)
-        self.assertEqual(_implicit_environ.get_default_project(),
-                         IMPLICIT_PROJECT)
-
-
 class Test_set_default_connection(unittest2.TestCase):
 
     def setUp(self):

gcloud/storage/test__implicit_environ.py

@@ -0,0 +1,162 @@
+# Copyright 2014 Google Inc. All rights reserved.
+#
+# 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 unittest2
+
+
+class Test__get_production_project(unittest2.TestCase):
+
+    def _callFUT(self):
+        from gcloud.storage import _implicit_environ
+        return _implicit_environ._get_production_project()
+
+    def test_no_value(self):
+        import os
+        from gcloud._testing import _Monkey
+
+        environ = {}
+        with _Monkey(os, getenv=environ.get):
+            project = self._callFUT()
+            self.assertEqual(project, None)
+
+    def test_value_set(self):
+        import os
+        from gcloud._testing import _Monkey
+        from gcloud.storage._implicit_environ import _PROJECT_ENV_VAR_NAME
+
+        MOCK_PROJECT = object()
+        environ = {_PROJECT_ENV_VAR_NAME: MOCK_PROJECT}
+        with _Monkey(os, getenv=environ.get):
+            project = self._callFUT()
+            self.assertEqual(project, MOCK_PROJECT)
+
+
+class Test__determine_default_project(unittest2.TestCase):
+
+    def _callFUT(self, project=None):
+        from gcloud.storage._implicit_environ import _determine_default_project
+        return _determine_default_project(project=project)
+
+    def _determine_default_helper(self, prod=None, project=None):
+        from gcloud._testing import _Monkey
+        from gcloud.storage import _implicit_environ
+
+        _callers = []
+
+        def prod_mock():
+            _callers.append('prod_mock')
+            return prod
+
+        patched_methods = {
+            '_get_production_project': prod_mock,
+        }
+
+        with _Monkey(_implicit_environ, **patched_methods):
+            returned_project = self._callFUT(project)
+
+        return returned_project, _callers
+
+    def test_no_value(self):
+        project, callers = self._determine_default_helper()
+        self.assertEqual(project, None)
+        self.assertEqual(callers, ['prod_mock'])
+
+    def test_explicit(self):
+        PROJECT = object()
+        project, callers = self._determine_default_helper(project=PROJECT)
+        self.assertEqual(project, PROJECT)
+        self.assertEqual(callers, [])
+
+    def test_prod(self):
+        PROJECT = object()
+        project, callers = self._determine_default_helper(prod=PROJECT)
+        self.assertEqual(project, PROJECT)
+        self.assertEqual(callers, ['prod_mock'])
+
+
+class Test_set_default_project(unittest2.TestCase):
+
+    def setUp(self):
+        from gcloud.storage._testing import _setup_defaults
+        _setup_defaults(self)
+
+    def tearDown(self):
+        from gcloud.storage._testing import _tear_down_defaults
+        _tear_down_defaults(self)
+
+    def _callFUT(self, project=None):
+        from gcloud.storage._implicit_environ import set_default_project
+        return set_default_project(project=project)
+
+    def test_raises(self):
+        from gcloud._testing import _Monkey
+        from gcloud.storage import _implicit_environ
+
+        _called_project = []
+
+        def mock_determine(project):
+            _called_project.append(project)
+            return None
+
+        with _Monkey(_implicit_environ,
+                     _determine_default_project=mock_determine):
+            self.assertRaises(EnvironmentError, self._callFUT)
+
+        self.assertEqual(_called_project, [None])
+
+    def test_set_correctly(self):
+        from gcloud._testing import _Monkey
+        from gcloud.storage import _implicit_environ
+
+        self.assertEqual(_implicit_environ._DEFAULTS.project, None)
+
+        PROJECT = object()
+        _called_project = []
+
+        def mock_determine(project):
+            _called_project.append(project)
+            return PROJECT
+
+        with _Monkey(_implicit_environ,
+                     _determine_default_project=mock_determine):
+            self._callFUT()
+
+        self.assertEqual(_implicit_environ._DEFAULTS.project, PROJECT)
+        self.assertEqual(_called_project, [None])
+
+
+class Test_lazy_loading(unittest2.TestCase):
+
+    def setUp(self):
+        from gcloud.storage._testing import _setup_defaults
+        _setup_defaults(self, implicit=True)
+
+    def tearDown(self):
+        from gcloud.storage._testing import _tear_down_defaults
+        _tear_down_defaults(self)
+
+    def test_descriptor_for_project(self):
+        from gcloud._testing import _Monkey
+        from gcloud.storage import _implicit_environ
+
+        self.assertFalse('project' in _implicit_environ._DEFAULTS.__dict__)
+
+        DEFAULT = object()
+
+        with _Monkey(_implicit_environ,
+                     _determine_default_project=lambda: DEFAULT):
+            lazy_loaded = _implicit_environ._DEFAULTS.project
+
+        self.assertEqual(lazy_loaded, DEFAULT)
+        self.assertTrue('project' in _implicit_environ._DEFAULTS.__dict__)

regression/storage.py

@@ -20,13 +20,14 @@
 from gcloud import exceptions
 from gcloud import storage
 from gcloud.storage._helpers import _base64_md5hash
+from gcloud.storage import _implicit_environ
 from gcloud.storage.batch import Batch
 
 
 HTTP = httplib2.Http()
 SHARED_BUCKETS = {}
 
-storage._PROJECT_ENV_VAR_NAME = 'GCLOUD_TESTS_PROJECT_ID'
+_implicit_environ._PROJECT_ENV_VAR_NAME = 'GCLOUD_TESTS_PROJECT_ID'
 storage.set_defaults()