s3api: Make the 'Quiet' key value case insensitive

When deleting multiple objects, S3 allows to enable
a quiet mode with the 'Quiet' key.

At AWS S3, the value of this key is case-insensitive.
- Quiet mode is enabled if the value is 'true'
  (regardless of case).
- Otherwise, in all other cases (even a non-boolean value),
  this mode will be disabled.

Also, some tools (like Minio's python API) send the value 'True'
(and not 'true').

Change-Id: Id9d1da2017b8d13242ae1f410347febb013e9ce1

doc/s3api/rnc/delete.rnc

@@ -1,6 +1,6 @@
 start =
   element Delete {
-    element Quiet { xsd:boolean }? &
+    element Quiet { xsd:string }? &
     element Object {
       element Key { xsd:string } &
       element VersionId { xsd:string }?

swift/common/middleware/s3api/controllers/multi_delete.py

@@ -81,10 +81,7 @@ class MultiObjectDeleteController(Controller):
             elem = fromstring(xml, 'Delete', self.logger)
 
             quiet = elem.find('./Quiet')
-            if quiet is not None and quiet.text.lower() == 'true':
-                self.quiet = True
-            else:
-                self.quiet = False
+            self.quiet = quiet is not None and quiet.text.lower() == 'true'
 
             delete_list = list(object_key_iter(elem))
             if len(delete_list) > self.conf.max_multi_delete_objects:

swift/common/middleware/s3api/schema/delete.rng

@@ -5,7 +5,7 @@
       <interleave>
         <optional>
           <element name="Quiet">
-            <data type="boolean"/>
+            <data type="string"/>
           </element>
         </optional>
         <oneOrMore>

test/unit/common/middleware/s3api/test_multi_delete.py

@@ -249,8 +249,9 @@ class TestS3ApiMultiDelete(S3ApiTestCase):
         self.swift.register('DELETE', '/v1/AUTH_test/bucket/Key2',
                             swob.HTTPNotFound, {}, None)
 
+        for true_value in ('true', 'True', 'TRUE', 'trUE'):
             elem = Element('Delete')
-        SubElement(elem, 'Quiet').text = 'true'
+            SubElement(elem, 'Quiet').text = true_value
             for key in ['Key1', 'Key2']:
                 obj = SubElement(elem, 'Object')
                 SubElement(obj, 'Key').text = key
@@ -260,7 +261,8 @@ class TestS3ApiMultiDelete(S3ApiTestCase):
 
             req = Request.blank('/bucket?delete',
                                 environ={'REQUEST_METHOD': 'POST'},
-                            headers={'Authorization': 'AWS test:tester:hmac',
+                                headers={
+                                    'Authorization': 'AWS test:tester:hmac',
                                     'Date': self.get_date_header(),
                                     'Content-MD5': content_md5},
                                 body=body)