s3api: fix the copy of non-ASCII objects

Trying to copy an object with non-ASCII characters in its name results
in, depending on the pipeline:
- an error code 412 because of a badly urlencoded path
- an error code 500 "TypeError: Expected a WSGI string"

This commit fixes the problem by calling str_to_wsgi on the object name
after it has been urldecoded. We do not need to call this on the
container name because it is supposed to contain only ASCII characters.

Change-Id: If837d4e55735b10a783c85d91f37fbea5e3baf1d

swift/common/middleware/s3api/s3request.py

@@ -910,7 +910,8 @@ class S3Request(swob.Request):
         headers = swob.HeaderKeyDict()
         headers.update(self._copy_source_headers())
 
-        src_resp = self.get_response(app, 'HEAD', src_bucket, src_obj,
+        src_resp = self.get_response(app, 'HEAD', src_bucket,
+                                     swob.str_to_wsgi(src_obj),
                                      headers=headers, query=query)
         if src_resp.status_int == 304:  # pylint: disable-msg=E1101
             raise PreconditionFailed()

test/functional/s3api/test_object.py

@@ -1,4 +1,5 @@
-# Copyright (c) 2015 OpenStack Foundation
+# -*- coding: utf-8 -*-
+# Copyright (c) 2015-2021 OpenStack Foundation
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -25,12 +26,11 @@ import email.parser
 from email.utils import formatdate, parsedate
 from time import mktime
 import six
-from six.moves.urllib.parse import quote
 
 import test.functional as tf
 
 from swift.common.middleware.s3api.etree import fromstring
-from swift.common.utils import md5
+from swift.common.utils import md5, quote
 
 from test.functional.s3api import S3ApiBase
 from test.functional.s3api.s3_test_client import Connection
@@ -59,7 +59,7 @@ class TestS3ApiObject(S3ApiBase):
         self.assertCommonResponseHeaders(headers, etag)
 
     def test_object(self):
-        obj = 'object name with %-sign'
+        obj = u'object name with %-sign 🙂'
         content = b'abc123'
         etag = md5(content, usedforsecurity=False).hexdigest()