Stub out ?versioning command.

This is necessary for CyberDuck, which issues the versioning command and errors
out if that doesn't work. This implementation simply returns that versioning
hasn't been configured.

swift3/middleware.py

@@ -270,7 +270,7 @@ def canonical_string(req):
         path, args = path.split('?', 1)
         for key in urlparse.parse_qs(args, keep_blank_values=True):
             if key in ('acl', 'logging', 'torrent', 'location',
-                       'requestPayment'):
+                       'requestPayment', 'versioning'):
                 return "%s%s?%s" % (buf, path, key)
     return buf + path
 
@@ -431,6 +431,12 @@ class BucketController(WSGIContext):
         if 'acl' in args:
             return get_acl(self.account_name, headers)
 
+        if 'versioning' in args:
+            # Just report there is no versioning configured here.
+            body = ('<VersioningConfiguration '
+                'xmlns="http://s3.amazonaws.com/doc/2006-03-01/"/>')
+            return Response(body=body, content_type="text/plain")
+
         if status != HTTP_OK:
             if status == HTTP_UNAUTHORIZED:
                 return get_err_response('AccessDenied')

swift3/test/unit/test_swift3.py

@@ -408,6 +408,16 @@ class TestSwift3(unittest.TestCase):
         resp = local_app(req.environ, local_app.app.do_start_response)
         self._check_acl('test:tester', resp)
 
+    def test_bucket_versioning_GET(self):
+        local_app = swift3.filter_factory({})(FakeAppBucket())
+        bucket_name = 'junk'
+        req = Request.blank('/%s?versioning' % bucket_name,
+                            environ={'REQUEST_METHOD': 'GET'},
+                            headers={'Authorization': 'AWS test:tester:hmac'})
+        resp = local_app(req.environ, local_app.app.do_start_response)
+        dom = xml.dom.minidom.parseString("".join(resp))
+        self.assertEquals(dom.firstChild.nodeName, 'VersioningConfiguration')
+
     def _test_object_GETorHEAD(self, method):
         local_app = swift3.filter_factory({})(FakeAppObject())
         req = Request.blank('/bucket/object',