Merge lp:~notmyname/swift/end_marker into lp:~hudson-openstack/swift/trunk

[John Dickinson]

added end_marker query parameter for container and object listings

Added end_marker query parameter for container and object listings. end_marker filters on the name <= end_marker

[John Dickinson (notmyname)]

I think "end_marker" is a good name, but better ones may be suggested. It's a lot easier to change it now.

[Chuck Thier (cthier)]

in swift/common/internal_proxy.py, you forgot to change marker to end_marker, and a test for that functionality would be nice :)

review: Needs Fixing

[John Dickinson (notmyname)]

fixed the erroneous marker to be end_marker

tests for internal_proxy would be very good, but they are not in the scope of this branch

review: Needs Resubmitting

[Chuck Thier (cthier)]

I get the following error when I run the unit tests:

ERROR: test_get_container_listing (test.unit.stats.test_log_processor.TestLogProcessor)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/cthier/swift/end_marker/test/unit/stats/test_log_processor.py", line 173, in test_get_container_listing
    result = p.get_container_listing('a', 'foo')
  File "/home/cthier/swift/end_marker/swift/stats/log_processor.py", line 162, in get_container_listing
    end_marker=end_key)
TypeError: get_container_list() got an unexpected keyword argument 'end_marker'

review: Needs Fixing

[Chuck Thier (cthier)]

Looks good to me now. All unit and functional tests pass.

review: Approve

=== modified file 'swift/account/reaper.py'
--- swift/account/reaper.py	2010-09-06 04:06:16 +0000
+++ swift/account/reaper.py	2010-11-17 15:38:03 +0000
@@ -224,7 +224,8 @@
             marker = ''
             while True:
                 containers = \
-                    list(broker.list_containers_iter(1000, marker, None, None))
+                    list(broker.list_containers_iter(1000, marker, None, None,
+                                                     None))
                 if not containers:
                     break
                 try:
 
=== modified file 'swift/account/server.py'
--- swift/account/server.py	2010-11-02 18:32:18 +0000
+++ swift/account/server.py	2010-11-17 15:38:03 +0000
@@ -200,6 +200,7 @@
                     return  HTTPPreconditionFailed(request=req,
                         body='Maximum limit is %d' % ACCOUNT_LISTING_LIMIT)
             marker = get_param(req, 'marker', '')
+            end_marker = get_param(req, 'end_marker')
             query_format = get_param(req, 'format')
         except UnicodeDecodeError, err:
             return HTTPBadRequest(body='parameters not utf8',
@@ -210,8 +211,8 @@
                                 ['text/plain', 'application/json',
                                  'application/xml', 'text/xml'],
                                 default_match='text/plain')
-        account_list = broker.list_containers_iter(limit, marker, prefix,
-                                                  delimiter)
+        account_list = broker.list_containers_iter(limit, marker, end_marker,
+                                                   prefix, delimiter)
         if out_content_type == 'application/json':
             json_pattern = ['"name":%s', '"count":%s', '"bytes":%s']
             json_pattern = '{' + ','.join(json_pattern) + '}'
 
=== modified file 'swift/common/db.py'
--- swift/common/db.py	2010-08-16 22:30:27 +0000
+++ swift/common/db.py	2010-11-17 15:38:03 +0000
@@ -940,8 +940,8 @@
                     rv.append(row['name'])
         return list(set(rv))
 
-    def list_objects_iter(self, limit, marker, prefix, delimiter, path=None,
-                          format=None):
+    def list_objects_iter(self, limit, marker, end_marker, prefix, delimiter,
+                          path=None, format=None):
         """
         Get a list of objects sorted by name starting at marker onward, up
         to limit entries.  Entries will begin with the prefix and will not
@@ -949,6 +949,7 @@
 
         :param limit: maximum number of entries to get
         :param marker: marker query
+        :param end_marker: end marker query
         :param prefix: prefix query
         :param delimeter: delimeter for query
         :param path: if defined, will set the prefix and delimter based on
@@ -977,6 +978,9 @@
                 query = '''SELECT name, created_at, size, content_type, etag
                            FROM object WHERE'''
                 query_args = []
+                if end_marker:
+                    query += ' name <= ? AND'
+                    query_args.append(end_marker)
                 if marker and marker >= prefix:
                     query += ' name > ? AND'
                     query_args.append(marker)
@@ -1440,7 +1444,8 @@
                     rv.append(row['name'])
         return list(set(rv))
 
-    def list_containers_iter(self, limit, marker, prefix, delimiter):
+    def list_containers_iter(self, limit, marker, end_marker, prefix,
+                             delimiter):
         """
         Get a list of containerss sorted by name starting at marker onward, up
         to limit entries.  Entries will begin with the prefix and will not
@@ -1448,6 +1453,7 @@
 
         :param limit: maximum number of entries to get
         :param marker: marker query
+        :param end_marker: end marker query
         :param prefix: prefix query
         :param delimeter: delimeter for query
 
@@ -1469,6 +1475,9 @@
                     FROM container
                     WHERE deleted = 0 AND """
                 query_args = []
+                if end_marker:
+                    query += ' name <= ? AND'
+                    query_args.append(end_marker)
                 if marker and marker >= prefix:
                     query += ' name > ? AND'
                     query_args.append(marker)
 
=== modified file 'swift/common/internal_proxy.py'
--- swift/common/internal_proxy.py	2010-10-04 21:12:43 +0000
+++ swift/common/internal_proxy.py	2010-11-17 15:38:03 +0000
@@ -156,14 +156,16 @@
             tries += 1
         return 200 <= resp.status_int < 300
 
-    def get_container_list(self, account, container, marker=None, limit=None,
-                           prefix=None, delimiter=None, full_listing=True):
+    def get_container_list(self, account, container, marker=None,
+                           end_marker=None, limit=None, prefix=None,
+                           delimiter=None, full_listing=True):
         """
         Get container listing.
 
         :param account: account name for the container
         :param container: container name to get the listing of
         :param marker: marker query
+        :param end_marker: end marker query
         :param limit: limit to query
         :param prefix: prefix query
         :param delimeter: delimeter for query
@@ -173,7 +175,7 @@
         if full_listing:
             rv = []
             listing = self.get_container_list(account, container, marker,
-                limit, prefix, delimiter, full_listing=False)
+                end_marker, limit, prefix, delimiter, full_listing=False)
             while listing:
                 rv.extend(listing)
                 if not delimiter:
@@ -181,12 +183,14 @@
                 else:
                     marker = listing[-1].get('name', listing[-1].get('subdir'))
                 listing = self.get_container_list(account, container, marker,
-                    limit, prefix, delimiter, full_listing=False)
+                    end_marker, limit, prefix, delimiter, full_listing=False)
             return rv
         path = '/v1/%s/%s' % (account, container)
         qs = 'format=json'
         if marker:
             qs += '&marker=%s' % quote(marker)
+        if end_marker:
+            qs += '&end_marker=%s' % quote(end_marker)
         if limit:
             qs += '&limit=%d' % limit
         if prefix:
 
=== modified file 'swift/container/server.py'
--- swift/container/server.py	2010-11-02 18:32:18 +0000
+++ swift/container/server.py	2010-11-17 15:38:03 +0000
@@ -267,6 +267,7 @@
                 # delimiters can be made more flexible later
                 return HTTPPreconditionFailed(body='Bad delimiter')
             marker = get_param(req, 'marker', '')
+            end_marker = get_param(req, 'end_marker')
             limit = CONTAINER_LISTING_LIMIT
             given_limit = get_param(req, 'limit')
             if given_limit and given_limit.isdigit():
@@ -284,8 +285,8 @@
                                 ['text/plain', 'application/json',
                                  'application/xml', 'text/xml'],
                                 default_match='text/plain')
-        container_list = broker.list_objects_iter(limit, marker, prefix,
-                                                  delimiter, path)
+        container_list = broker.list_objects_iter(limit, marker, end_marker,
+                                                  prefix, delimiter, path)
         if out_content_type == 'application/json':
             json_pattern = ['"name":%s', '"hash":"%s"', '"bytes":%s',
                             '"content_type":%s, "last_modified":"%s"']
 
=== modified file 'swift/stats/log_processor.py'
--- swift/stats/log_processor.py	2010-11-04 19:56:08 +0000
+++ swift/stats/log_processor.py	2010-11-17 15:38:03 +0000
@@ -158,15 +158,14 @@
         container_listing = self.internal_proxy.get_container_list(
                                     swift_account,
                                     container_name,
-                                    marker=search_key)
+                                    marker=search_key,
+                                    end_marker=end_key)
         results = []
         if container_listing is not None:
             if listing_filter is None:
                 listing_filter = set()
             for item in container_listing:
                 name = item['name']
-                if end_key and name > end_key:
-                    break
                 if name not in listing_filter:
                     results.append(name)
         return results
 
=== modified file 'test/unit/common/test_db.py'
--- test/unit/common/test_db.py	2010-08-16 22:30:27 +0000
+++ test/unit/common/test_db.py	2010-11-17 15:38:03 +0000
@@ -978,52 +978,57 @@
                               normalize_timestamp(time()), 0, 'text/plain',
                               'd41d8cd98f00b204e9800998ecf8427e')
 
-        listing = broker.list_objects_iter(100, '', None, '')
+        listing = broker.list_objects_iter(100, '', None, None, '')
         self.assertEquals(len(listing), 100)
         self.assertEquals(listing[0][0], '0/0000')
         self.assertEquals(listing[-1][0], '0/0099')
 
-        listing = broker.list_objects_iter(100, '0/0099', None, '')
+        listing = broker.list_objects_iter(100, '', '0/0050', None, '')
+        self.assertEquals(len(listing), 51)
+        self.assertEquals(listing[0][0], '0/0000')
+        self.assertEquals(listing[-1][0], '0/0050')
+
+        listing = broker.list_objects_iter(100, '0/0099', None, None, '')
         self.assertEquals(len(listing), 100)
         self.assertEquals(listing[0][0], '0/0100')
         self.assertEquals(listing[-1][0], '1/0074')
 
-        listing = broker.list_objects_iter(55, '1/0074', None, '')
+        listing = broker.list_objects_iter(55, '1/0074', None, None, '')
         self.assertEquals(len(listing), 55)
         self.assertEquals(listing[0][0], '1/0075')
         self.assertEquals(listing[-1][0], '2/0004')
 
-        listing = broker.list_objects_iter(10, '', '0/01', '')
+        listing = broker.list_objects_iter(10, '', None, '0/01', '')
         self.assertEquals(len(listing), 10)
         self.assertEquals(listing[0][0], '0/0100')
         self.assertEquals(listing[-1][0], '0/0109')
 
-        listing = broker.list_objects_iter(10, '', '0/', '/')
+        listing = broker.list_objects_iter(10, '', None, '0/', '/')
         self.assertEquals(len(listing), 10)
         self.assertEquals(listing[0][0], '0/0000')
         self.assertEquals(listing[-1][0], '0/0009')
 
-        listing = broker.list_objects_iter(10, '', '', '/')
+        listing = broker.list_objects_iter(10, '', None, '', '/')
         self.assertEquals(len(listing), 4)
         self.assertEquals([row[0] for row in listing],
                           ['0/', '1/', '2/', '3/'])
 
-        listing = broker.list_objects_iter(10, '2', None, '/')
+        listing = broker.list_objects_iter(10, '2', None, None, '/')
         self.assertEquals(len(listing), 2)
         self.assertEquals([row[0] for row in listing], ['2/', '3/'])
 
-        listing = broker.list_objects_iter(10, '2/', None, '/')
+        listing = broker.list_objects_iter(10, '2/',None,  None, '/')
         self.assertEquals(len(listing), 1)
         self.assertEquals([row[0] for row in listing], ['3/'])
 
-        listing = broker.list_objects_iter(10, '2/0050', '2/', '/')
+        listing = broker.list_objects_iter(10, '2/0050', None, '2/', '/')
         self.assertEquals(len(listing), 10)
         self.assertEquals(listing[0][0], '2/0051')
         self.assertEquals(listing[1][0], '2/0051/')
         self.assertEquals(listing[2][0], '2/0052')
         self.assertEquals(listing[-1][0], '2/0059')
 
-        listing = broker.list_objects_iter(10, '3/0045', '3/', '/')
+        listing = broker.list_objects_iter(10, '3/0045', None, '3/', '/')
         self.assertEquals(len(listing), 10)
         self.assertEquals([row[0] for row in listing],
                            ['3/0045/', '3/0046', '3/0046/', '3/0047',
@@ -1032,33 +1037,34 @@
 
         broker.put_object('3/0049/', normalize_timestamp(time()), 0,
                           'text/plain', 'd41d8cd98f00b204e9800998ecf8427e')
-        listing = broker.list_objects_iter(10, '3/0048', None, None)
+        listing = broker.list_objects_iter(10, '3/0048', None, None, None)
         self.assertEquals(len(listing), 10)
         self.assertEquals([row[0] for row in listing],
             ['3/0048/0049', '3/0049', '3/0049/',
             '3/0049/0049', '3/0050', '3/0050/0049', '3/0051', '3/0051/0049',
             '3/0052', '3/0052/0049'])
 
-        listing = broker.list_objects_iter(10, '3/0048', '3/', '/')
+        listing = broker.list_objects_iter(10, '3/0048', None, '3/', '/')
         self.assertEquals(len(listing), 10)
         self.assertEquals([row[0] for row in listing],
             ['3/0048/', '3/0049', '3/0049/', '3/0050',
             '3/0050/', '3/0051', '3/0051/', '3/0052', '3/0052/', '3/0053'])
 
-        listing = broker.list_objects_iter(10, None, '3/0049/', '/')
+        listing = broker.list_objects_iter(10, None, None, '3/0049/', '/')
         self.assertEquals(len(listing), 2)
         self.assertEquals([row[0] for row in listing],
             ['3/0049/', '3/0049/0049'])
 
-        listing = broker.list_objects_iter(10, None, None, None, '3/0049')
+        listing = broker.list_objects_iter(10, None, None, None, None,
+                                           '3/0049')
         self.assertEquals(len(listing), 1)
         self.assertEquals([row[0] for row in listing], ['3/0049/0049'])
 
-        listing = broker.list_objects_iter(2, None, '3/', '/')
+        listing = broker.list_objects_iter(2, None, None, '3/', '/')
         self.assertEquals(len(listing), 2)
         self.assertEquals([row[0] for row in listing], ['3/0000', '3/0000/'])
 
-        listing = broker.list_objects_iter(2, None, None, None, '3')
+        listing = broker.list_objects_iter(2, None, None, None, None, '3')
         self.assertEquals(len(listing), 2)
         self.assertEquals([row[0] for row in listing], ['3/0000', '3/0001'])
 
@@ -1082,11 +1088,11 @@
 
         #def list_objects_iter(self, limit, marker, prefix, delimiter, path=None,
         #                          format=None):
-        listing = broker.list_objects_iter(100, None, '/pets/f', '/')
-        self.assertEquals([row[0] for row in listing], ['/pets/fish/', '/pets/fish_info.txt'])
-        listing = broker.list_objects_iter(100, None, '/pets/fish', '/')
-        self.assertEquals([row[0] for row in listing], ['/pets/fish/', '/pets/fish_info.txt'])
-        listing = broker.list_objects_iter(100, None, '/pets/fish/', '/')
+        listing = broker.list_objects_iter(100, None, None, '/pets/f', '/')
+        self.assertEquals([row[0] for row in listing], ['/pets/fish/', '/pets/fish_info.txt'])
+        listing = broker.list_objects_iter(100, None, None, '/pets/fish', '/')
+        self.assertEquals([row[0] for row in listing], ['/pets/fish/', '/pets/fish_info.txt'])
+        listing = broker.list_objects_iter(100, None, None, '/pets/fish/', '/')
         self.assertEquals([row[0] for row in listing], ['/pets/fish/a', '/pets/fish/b'])
 
     def test_double_check_trailing_delimiter(self):
@@ -1114,19 +1120,19 @@
                           'text/plain', 'd41d8cd98f00b204e9800998ecf8427e')
         broker.put_object('c', normalize_timestamp(time()), 0,
                           'text/plain', 'd41d8cd98f00b204e9800998ecf8427e')
-        listing = broker.list_objects_iter(15, None, None, None)
+        listing = broker.list_objects_iter(15, None, None, None, None)
         self.assertEquals(len(listing), 10)
         self.assertEquals([row[0] for row in listing],
             ['a', 'a/', 'a/a', 'a/a/a', 'a/a/b', 'a/b', 'b', 'b/a', 'b/b', 'c'])
-        listing = broker.list_objects_iter(15, None, '', '/')
+        listing = broker.list_objects_iter(15, None, None, '', '/')
         self.assertEquals(len(listing), 5)
         self.assertEquals([row[0] for row in listing],
             ['a', 'a/', 'b', 'b/', 'c'])
-        listing = broker.list_objects_iter(15, None, 'a/', '/')
+        listing = broker.list_objects_iter(15, None, None, 'a/', '/')
         self.assertEquals(len(listing), 4)
         self.assertEquals([row[0] for row in listing],
             ['a/', 'a/a', 'a/a/', 'a/b'])
-        listing = broker.list_objects_iter(15, None, 'b/', '/')
+        listing = broker.list_objects_iter(15, None, None, 'b/', '/')
         self.assertEquals(len(listing), 2)
         self.assertEquals([row[0] for row in listing], ['b/a', 'b/b'])
 
@@ -1646,57 +1652,62 @@
             broker.put_container('3/%04d/0049' % cont,
                                  normalize_timestamp(time()), 0, 0, 0)
 
-        listing = broker.list_containers_iter(100, '', None, '')
+        listing = broker.list_containers_iter(100, '', None, None, '')
         self.assertEquals(len(listing), 100)
         self.assertEquals(listing[0][0], '0/0000')
         self.assertEquals(listing[-1][0], '0/0099')
 
-        listing = broker.list_containers_iter(100, '0/0099', None, '')
+        listing = broker.list_containers_iter(100, '', '0/0050', None, '')
+        self.assertEquals(len(listing), 51)
+        self.assertEquals(listing[0][0], '0/0000')
+        self.assertEquals(listing[-1][0], '0/0050')
+
+        listing = broker.list_containers_iter(100, '0/0099', None, None, '')
         self.assertEquals(len(listing), 100)
         self.assertEquals(listing[0][0], '0/0100')
         self.assertEquals(listing[-1][0], '1/0074')
 
-        listing = broker.list_containers_iter(55, '1/0074', None, '')
+        listing = broker.list_containers_iter(55, '1/0074', None, None, '')
         self.assertEquals(len(listing), 55)
         self.assertEquals(listing[0][0], '1/0075')
         self.assertEquals(listing[-1][0], '2/0004')
 
-        listing = broker.list_containers_iter(10, '', '0/01', '')
-        self.assertEquals(len(listing), 10)
-        self.assertEquals(listing[0][0], '0/0100')
-        self.assertEquals(listing[-1][0], '0/0109')
-
-        listing = broker.list_containers_iter(10, '', '0/01', '/')
-        self.assertEquals(len(listing), 10)
-        self.assertEquals(listing[0][0], '0/0100')
-        self.assertEquals(listing[-1][0], '0/0109')
-
-        listing = broker.list_containers_iter(10, '', '0/', '/')
+        listing = broker.list_containers_iter(10, '', None, '0/01', '')
+        self.assertEquals(len(listing), 10)
+        self.assertEquals(listing[0][0], '0/0100')
+        self.assertEquals(listing[-1][0], '0/0109')
+
+        listing = broker.list_containers_iter(10, '', None, '0/01', '/')
+        self.assertEquals(len(listing), 10)
+        self.assertEquals(listing[0][0], '0/0100')
+        self.assertEquals(listing[-1][0], '0/0109')
+
+        listing = broker.list_containers_iter(10, '', None, '0/', '/')
         self.assertEquals(len(listing), 10)
         self.assertEquals(listing[0][0], '0/0000')
         self.assertEquals(listing[-1][0], '0/0009')
 
-        listing = broker.list_containers_iter(10, '', '', '/')
+        listing = broker.list_containers_iter(10, '', None, '', '/')
         self.assertEquals(len(listing), 4)
         self.assertEquals([row[0] for row in listing],
                           ['0/', '1/', '2/', '3/'])
 
-        listing = broker.list_containers_iter(10, '2/', None, '/')
+        listing = broker.list_containers_iter(10, '2/', None, None, '/')
         self.assertEquals(len(listing), 1)
         self.assertEquals([row[0] for row in listing], ['3/'])
 
-        listing = broker.list_containers_iter(10, '', '2', '/')
+        listing = broker.list_containers_iter(10, '', None, '2', '/')
         self.assertEquals(len(listing), 1)
         self.assertEquals([row[0] for row in listing], ['2/'])
 
-        listing = broker.list_containers_iter(10, '2/0050', '2/', '/')
+        listing = broker.list_containers_iter(10, '2/0050', None, '2/', '/')
         self.assertEquals(len(listing), 10)
         self.assertEquals(listing[0][0], '2/0051')
         self.assertEquals(listing[1][0], '2/0051/')
         self.assertEquals(listing[2][0], '2/0052')
         self.assertEquals(listing[-1][0], '2/0059')
 
-        listing = broker.list_containers_iter(10, '3/0045', '3/', '/')
+        listing = broker.list_containers_iter(10, '3/0045', None, '3/', '/')
         self.assertEquals(len(listing), 10)
         self.assertEquals([row[0] for row in listing],
                            ['3/0045/', '3/0046', '3/0046/', '3/0047',
@@ -1704,21 +1715,21 @@
                             '3/0049/', '3/0050'])
 
         broker.put_container('3/0049/', normalize_timestamp(time()), 0, 0, 0)
-        listing = broker.list_containers_iter(10, '3/0048', None, None)
+        listing = broker.list_containers_iter(10, '3/0048', None, None, None)
         self.assertEquals(len(listing), 10)
         self.assertEquals([row[0] for row in listing],
                            ['3/0048/0049', '3/0049', '3/0049/', '3/0049/0049',
                             '3/0050', '3/0050/0049', '3/0051', '3/0051/0049',
                             '3/0052', '3/0052/0049'])
 
-        listing = broker.list_containers_iter(10, '3/0048', '3/', '/')
+        listing = broker.list_containers_iter(10, '3/0048', None, '3/', '/')
         self.assertEquals(len(listing), 10)
         self.assertEquals([row[0] for row in listing],
                            ['3/0048/', '3/0049', '3/0049/', '3/0050',
                             '3/0050/', '3/0051', '3/0051/', '3/0052',
                             '3/0052/', '3/0053'])
 
-        listing = broker.list_containers_iter(10, None, '3/0049/', '/')
+        listing = broker.list_containers_iter(10, None, None, '3/0049/', '/')
         self.assertEquals(len(listing), 2)
         self.assertEquals([row[0] for row in listing],
                           ['3/0049/', '3/0049/0049'])
@@ -1738,20 +1749,20 @@
         broker.put_container('b/a', normalize_timestamp(time()), 0, 0, 0)
         broker.put_container('b/b', normalize_timestamp(time()), 0, 0, 0)
         broker.put_container('c', normalize_timestamp(time()), 0, 0, 0)
-        listing = broker.list_containers_iter(15, None, None, None)
+        listing = broker.list_containers_iter(15, None, None, None, None)
         self.assertEquals(len(listing), 10)
         self.assertEquals([row[0] for row in listing],
                            ['a', 'a/', 'a/a', 'a/a/a', 'a/a/b', 'a/b', 'b',
                             'b/a', 'b/b', 'c'])
-        listing = broker.list_containers_iter(15, None, '', '/')
+        listing = broker.list_containers_iter(15, None, None, '', '/')
         self.assertEquals(len(listing), 5)
         self.assertEquals([row[0] for row in listing],
                           ['a', 'a/', 'b', 'b/', 'c'])
-        listing = broker.list_containers_iter(15, None, 'a/', '/')
+        listing = broker.list_containers_iter(15, None, None, 'a/', '/')
         self.assertEquals(len(listing), 4)
         self.assertEquals([row[0] for row in listing],
                           ['a/', 'a/a', 'a/a/', 'a/b'])
-        listing = broker.list_containers_iter(15, None, 'b/', '/')
+        listing = broker.list_containers_iter(15, None, None, 'b/', '/')
         self.assertEquals(len(listing), 2)
         self.assertEquals([row[0] for row in listing], ['b/a', 'b/b'])
 
 
=== modified file 'test/unit/stats/test_log_processor.py'
--- test/unit/stats/test_log_processor.py	2010-11-05 05:26:53 +0000
+++ test/unit/stats/test_log_processor.py	2010-11-17 15:38:03 +0000
@@ -46,12 +46,16 @@
         pass
 
 class DumbInternalProxy(object):
-    def get_container_list(self, account, container, marker=None):
+    def get_container_list(self, account, container, marker=None,
+                           end_marker=None):
         n = '2010/03/14/13/obj1'
         if marker is None or n > marker:
+            if end_marker and n <= end_marker:
+                return [{'name': n}]
+            elif end_marker:
+                return []
             return [{'name': n}]
-        else:
-            return []
+        return []
 
     def get_object(self, account, container, object_name):
         code = 200