Merge pull request #622 from tseaver/move-thread_local_stack_up

Move the 'thread-local stack' implementation up from datastore.

Author: tseaver

gcloud/_localstack.py

@@ -0,0 +1,61 @@
+# 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.
+"""Thread-local resource stack.
+
+This module is not part of the public API surface of `gcloud`.
+"""
+
+try:
+    from threading import local as Local
+except ImportError:     # pragma: NO COVER (who doesn't have it?)
+    class Local(object):
+        """Placeholder for non-threaded applications."""
+
+
+class _LocalStack(Local):
+    """Manage a thread-local LIFO stack of resources.
+
+    Intended for use in :class:`gcloud.datastore.batch.Batch.__enter__`,
+    :class:`gcloud.storage.batch.Batch.__enter__`, etc.
+    """
+    def __init__(self):
+        super(_LocalStack, self).__init__()
+        self._stack = []
+
+    def __iter__(self):
+        """Iterate the stack in LIFO order.
+        """
+        return iter(reversed(self._stack))
+
+    def push(self, resource):
+        """Push a resource onto our stack.
+        """
+        self._stack.append(resource)
+
+    def pop(self):
+        """Pop a resource from our stack.
+
+        :raises: IndexError if the stack is empty.
+        :returns: the top-most resource, after removing it.
+        """
+        return self._stack.pop()
+
+    @property
+    def top(self):
+        """Get the top-most resource
+
+        :returns: the top-most item, or None if the stack is empty.
+        """
+        if len(self._stack) > 0:
+            return self._stack[-1]

gcloud/datastore/batch.py

@@ -13,66 +13,15 @@
 # limitations under the License.
 
 """Create / interact with a batch of updates / deletes."""
-try:
-    from threading import local as Local
-except ImportError:     # pragma: NO COVER (who doesn't have it?)
-    class Local(object):
-        """Placeholder for non-threaded applications."""
 
+from gcloud._localstack import _LocalStack
 from gcloud.datastore import _implicit_environ
 from gcloud.datastore import helpers
 from gcloud.datastore.key import _dataset_ids_equal
 from gcloud.datastore import _datastore_v1_pb2 as datastore_pb
 
 
-class _Batches(Local):
-    """Manage a thread-local LIFO stack of active batches / transactions.
-
-    Intended for use only in :class:`gcloud.datastore.batch.Batch.__enter__`
-    """
-    def __init__(self):
-        super(_Batches, self).__init__()
-        self._stack = []
-
-    def __iter__(self):
-        """Iterate the stack in LIFO order.
-        """
-        return iter(reversed(self._stack))
-
-    def push(self, batch):
-        """Push a batch / transaction onto our stack.
-
-        Intended for use only in :meth:`gcloud.datastore.batch.Batch.__enter__`
-
-        :type batch: :class:`gcloud.datastore.batch.Batch` or
-                    :class:`gcloud.datastore.transaction.Transaction`
-        """
-        self._stack.append(batch)
-
-    def pop(self):
-        """Pop a batch / transaction from our stack.
-
-        Intended for use only in :meth:`gcloud.datastore.batch.Batch.__enter__`
-
-        :rtype: :class:`gcloud.datastore.batch.Batch` or
-                :class:`gcloud.datastore.transaction.Transaction`
-        :raises: IndexError if the stack is empty.
-        """
-        return self._stack.pop()
-
-    @property
-    def top(self):
-        """Get the top-most batch / transaction
-
-        :rtype: :class:`gcloud.datastore.batch.Batch` or
-                :class:`gcloud.datastore.transaction.Transaction` or None
-        :returns: the top-most item, or None if the stack is empty.
-        """
-        if len(self._stack) > 0:
-            return self._stack[-1]
-
-
-_BATCHES = _Batches()
+_BATCHES = _LocalStack()
 
 
 class Batch(object):

gcloud/datastore/test_batch.py

@@ -15,34 +15,6 @@
 import unittest2
 
 
-class Test_Batches(unittest2.TestCase):
-
-    def _getTargetClass(self):
-        from gcloud.datastore.batch import _Batches
-
-        return _Batches
-
-    def _makeOne(self):
-        return self._getTargetClass()()
-
-    def test_it(self):
-        batch1, batch2 = object(), object()
-        batches = self._makeOne()
-        self.assertEqual(list(batches), [])
-        self.assertTrue(batches.top is None)
-        batches.push(batch1)
-        self.assertTrue(batches.top is batch1)
-        batches.push(batch2)
-        self.assertTrue(batches.top is batch2)
-        popped = batches.pop()
-        self.assertTrue(popped is batch2)
-        self.assertTrue(batches.top is batch1)
-        self.assertEqual(list(batches), [batch1])
-        popped = batches.pop()
-        self.assertTrue(batches.top is None)
-        self.assertEqual(list(batches), [])
-
-
 class TestBatch(unittest2.TestCase):
 
     def _getTargetClass(self):

gcloud/test__localstack.py

@@ -0,0 +1,43 @@
+# 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__LocalStack(unittest2.TestCase):
+
+    def _getTargetClass(self):
+        from gcloud._localstack import _LocalStack
+
+        return _LocalStack
+
+    def _makeOne(self):
+        return self._getTargetClass()()
+
+    def test_it(self):
+        batch1, batch2 = object(), object()
+        batches = self._makeOne()
+        self.assertEqual(list(batches), [])
+        self.assertTrue(batches.top is None)
+        batches.push(batch1)
+        self.assertTrue(batches.top is batch1)
+        batches.push(batch2)
+        self.assertTrue(batches.top is batch2)
+        popped = batches.pop()
+        self.assertTrue(popped is batch2)
+        self.assertTrue(batches.top is batch1)
+        self.assertEqual(list(batches), [batch1])
+        popped = batches.pop()
+        self.assertTrue(batches.top is None)
+        self.assertEqual(list(batches), [])