Add support for the Bucket's 'versioning' field.

See: https://cloud.google.com/storage/docs/object-versioning

Addresses part of #314.

Author: tseaver

gcloud/storage/bucket.py

@@ -25,6 +25,7 @@ class Bucket(_MetadataMixin):
         'acl': 'get_acl',
         'defaultObjectAcl': 'get_default_object_acl',
         'lifecycle': 'get_lifecycle',
+        'versioning': 'get_versioning',
     }
     """Mapping of field name -> accessor for fields w/ custom accessors."""
 
@@ -471,6 +472,36 @@ def update_lifecycle(self, rules):
         """
         self.patch_metadata({'lifecycle': {'rule': rules}})
 
+    def get_versioning(self):
+        """Is versioning enabled for this bucket?
+
+        See:  https://cloud.google.com/storage/docs/object-versioning for
+        details.
+
+        :rtype: boolean
+        :returns: True if enabled, else False.
+        """
+        if not self.has_metadata(field='versioning'):
+            self.reload_metadata()
+        versioning = self.metadata.get('versioning', {})
+        return versioning.get('enabled', False)
+
+    def enable_versioning(self):
+        """Enable versioning for this bucket.
+
+        See:  https://cloud.google.com/storage/docs/object-versioning for
+        details.
+        """
+        self.patch_metadata({'versioning': {'enabled': True}})
+
+    def disable_versioning(self):
+        """Disable versioning for this bucket.
+
+        See:  https://cloud.google.com/storage/docs/object-versioning for
+        details.
+        """
+        self.patch_metadata({'versioning': {'enabled': False}})
+
 
 class BucketIterator(Iterator):
     """An iterator listing all buckets.

gcloud/storage/test_bucket.py

@@ -781,6 +781,60 @@ def test_update_lifecycle(self):
         self.assertEqual(entries[0]['action']['type'], 'Delete')
         self.assertEqual(entries[0]['condition']['age'], 42)
 
+    def test_get_versioning_eager(self):
+        NAME = 'name'
+        before = {'bar': 'Bar', 'versioning': {'enabled': True}}
+        connection = _Connection()
+        bucket = self._makeOne(connection, NAME, before)
+        self.assertEqual(bucket.get_versioning(), True)
+        kw = connection._requested
+        self.assertEqual(len(kw), 0)
+
+    def test_get_versioning_lazy(self):
+        NAME = 'name'
+        before = {'bar': 'Bar'}
+        after = {'bar': 'Bar', 'versioning': {'enabled': True}}
+        connection = _Connection(after)
+        bucket = self._makeOne(connection, NAME, before)
+        self.assertEqual(bucket.get_versioning(), True)
+        kw = connection._requested
+        self.assertEqual(len(kw), 1)
+        self.assertEqual(kw[0]['method'], 'GET')
+        self.assertEqual(kw[0]['path'], '/b/%s' % NAME)
+        self.assertEqual(kw[0]['query_params'], {'projection': 'noAcl'})
+
+    def test_enable_versioning(self):
+        NAME = 'name'
+        before = {'versioning': {'enabled': False}}
+        after = {'versioning': {'enabled': True}}
+        connection = _Connection(after)
+        bucket = self._makeOne(connection, NAME, before)
+        self.assertFalse(bucket.get_versioning())
+        bucket.enable_versioning()
+        self.assertTrue(bucket.get_versioning())
+        kw = connection._requested
+        self.assertEqual(len(kw), 1)
+        self.assertEqual(kw[0]['method'], 'PATCH')
+        self.assertEqual(kw[0]['path'], '/b/%s' % NAME)
+        self.assertEqual(kw[0]['data'], {'versioning': {'enabled': True}})
+        self.assertEqual(kw[0]['query_params'], {'projection': 'full'})
+
+    def test_disable_versioning(self):
+        NAME = 'name'
+        before = {'versioning': {'enabled': True}}
+        after = {'versioning': {'enabled': False}}
+        connection = _Connection(after)
+        bucket = self._makeOne(connection, NAME, before)
+        self.assertTrue(bucket.get_versioning())
+        bucket.disable_versioning()
+        self.assertFalse(bucket.get_versioning())
+        kw = connection._requested
+        self.assertEqual(len(kw), 1)
+        self.assertEqual(kw[0]['method'], 'PATCH')
+        self.assertEqual(kw[0]['path'], '/b/%s' % NAME)
+        self.assertEqual(kw[0]['data'], {'versioning': {'enabled': False}})
+        self.assertEqual(kw[0]['query_params'], {'projection': 'full'})
+
 
 class TestBucketIterator(unittest2.TestCase):