py3: Fix s3api header casing

Closes-Bug: #1853367

Change-Id: Ifb15ce50fc3bcfda9532a2c3dec542c272ea4933

swift/common/header_key_dict.py

@@ -16,13 +16,6 @@
 import six
 
 
-def _title(s):
-    if six.PY2:
-        return s.title()
-    else:
-        return s.encode('latin1').title().decode('latin1')
-
-
 class HeaderKeyDict(dict):
     """
     A dict that title-cases all keys on the way in, so as to be
@@ -36,35 +29,43 @@ class HeaderKeyDict(dict):
             self.update(base_headers)
         self.update(kwargs)
 
+    @staticmethod
+    def _title(s):
+        if six.PY2:
+            return s.title()
+        else:
+            return s.encode('latin1').title().decode('latin1')
+
     def update(self, other):
         if hasattr(other, 'keys'):
             for key in other.keys():
-                self[_title(key)] = other[key]
+                self[self._title(key)] = other[key]
         else:
             for key, value in other:
-                self[_title(key)] = value
+                self[self._title(key)] = value
 
     def __getitem__(self, key):
-        return dict.get(self, _title(key))
+        return dict.get(self, self._title(key))
 
     def __setitem__(self, key, value):
+        key = self._title(key)
         if value is None:
-            self.pop(_title(key), None)
+            self.pop(key, None)
         elif six.PY2 and isinstance(value, six.text_type):
-            return dict.__setitem__(self, _title(key), value.encode('utf-8'))
+            return dict.__setitem__(self, key, value.encode('utf-8'))
         elif six.PY3 and isinstance(value, six.binary_type):
-            return dict.__setitem__(self, _title(key), value.decode('latin-1'))
+            return dict.__setitem__(self, key, value.decode('latin-1'))
         else:
-            return dict.__setitem__(self, _title(key), str(value))
+            return dict.__setitem__(self, key, str(value))
 
     def __contains__(self, key):
-        return dict.__contains__(self, _title(key))
+        return dict.__contains__(self, self._title(key))
 
     def __delitem__(self, key):
-        return dict.__delitem__(self, _title(key))
+        return dict.__delitem__(self, self._title(key))
 
     def get(self, key, default=None):
-        return dict.get(self, _title(key), default)
+        return dict.get(self, self._title(key), default)
 
     def setdefault(self, key, value=None):
         if key not in self:
@@ -72,4 +73,4 @@ class HeaderKeyDict(dict):
         return self[key]
 
     def pop(self, key, default=None):
-        return dict.pop(self, _title(key), default)
+        return dict.pop(self, self._title(key), default)

swift/common/middleware/s3api/s3response.py

@@ -17,6 +17,7 @@ import re
 from collections import MutableMapping
 from functools import partial
 
+from swift.common import header_key_dict
 from swift.common import swob
 from swift.common.utils import config_true_value
 from swift.common.request_helpers import is_sys_meta
@@ -26,42 +27,21 @@ from swift.common.middleware.s3api.utils import snake_to_camel, \
 from swift.common.middleware.s3api.etree import Element, SubElement, tostring
 
 
-class HeaderKey(str):
+class HeaderKeyDict(header_key_dict.HeaderKeyDict):
     """
-    A string object that normalizes string as S3 clients expect with title().
+    Similar to the Swift's normal HeaderKeyDict class, but its key name is
+    normalized as S3 clients expect.
     """
-    def title(self):
-        if self.lower() == 'etag':
+    @staticmethod
+    def _title(s):
+        s = header_key_dict.HeaderKeyDict._title(s)
+        if s.lower() == 'etag':
             # AWS Java SDK expects only 'ETag'.
             return 'ETag'
-        if self.lower().startswith('x-amz-'):
+        if s.lower().startswith('x-amz-'):
             # AWS headers returned by S3 are lowercase.
-            return self.lower()
-        return str.title(self)
-
-
-class HeaderKeyDict(swob.HeaderKeyDict):
-    """
-    Similar to the HeaderKeyDict class in Swift, but its key name is normalized
-    as S3 clients expect.
-    """
-    def __getitem__(self, key):
-        return swob.HeaderKeyDict.__getitem__(self, HeaderKey(key))
-
-    def __setitem__(self, key, value):
-        return swob.HeaderKeyDict.__setitem__(self, HeaderKey(key), value)
-
-    def __contains__(self, key):
-        return swob.HeaderKeyDict.__contains__(self, HeaderKey(key))
-
-    def __delitem__(self, key):
-        return swob.HeaderKeyDict.__delitem__(self, HeaderKey(key))
-
-    def get(self, key, default=None):
-        return swob.HeaderKeyDict.get(self, HeaderKey(key), default)
-
-    def pop(self, key, default=None):
-        return swob.HeaderKeyDict.pop(self, HeaderKey(key), default)
+            return swob.bytes_to_wsgi(swob.wsgi_to_bytes(s).lower())
+        return s
 
 
 class S3ResponseBase(object):
@@ -116,7 +96,7 @@ class S3Response(S3ResponseBase, swob.Response):
 
         # Handle swift headers
         for key, val in sw_headers.items():
-            _key = key.lower()
+            _key = swob.bytes_to_wsgi(swob.wsgi_to_bytes(key).lower())
 
             if _key.startswith('x-object-meta-'):
                 # Note that AWS ignores user-defined headers with '=' in the

test/unit/common/middleware/s3api/test_s3response.py

@@ -35,6 +35,24 @@ class TestResponse(unittest.TestCase):
                 else:
                     self.assertEqual('"theetag"', s3resp.headers['ETag'])
 
+    def test_response_s3api_user_meta_headers(self):
+        resp = Response(headers={
+            'X-Object-Meta-Foo': 'Bar',
+            'X-Object-Meta-Non-\xdcnicode-Value': '\xff',
+            'X-Object-Sysmeta-Baz': 'quux',
+            'Etag': 'unquoted',
+            'Content-type': 'text/plain',
+            'content-length': '0',
+        })
+        s3resp = S3Response.from_swift_resp(resp)
+        self.assertEqual(dict(s3resp.headers), {
+            'x-amz-meta-foo': 'Bar',
+            'x-amz-meta-non-\xdcnicode-value': '\xff',
+            'ETag': '"unquoted"',
+            'Content-Type': 'text/plain',
+            'Content-Length': '0',
+        })
+
     def test_response_s3api_sysmeta_headers(self):
         for _server_type in ('object', 'container'):
             swift_headers = HeaderKeyDict(