Revert ffc7cae / PR #1239

The change caused a regression documented in issue #1290

Author: dpkp

kafka/consumer/fetcher.py

@@ -838,17 +838,12 @@ def _parse_fetched_data(self, completed_fetch):
 
         return parsed_records
 
-    class PartitionRecords(object):
+    class PartitionRecords(six.Iterator):
         def __init__(self, fetch_offset, tp, messages):
             self.fetch_offset = fetch_offset
             self.topic_partition = tp
             self.messages = messages
-            # When fetching an offset that is in the middle of a
-            # compressed batch, we will get all messages in the batch.
-            # But we want to start 'take' at the fetch_offset
-            for i, msg in enumerate(messages):
-                if msg.offset == fetch_offset:
-                    self.message_idx = i
+            self.message_idx = 0
 
         # For truthiness evaluation we need to define __len__ or __nonzero__
         def __len__(self):

test/test_fetcher.py

@@ -303,29 +303,6 @@ def test__handle_offset_response(fetcher, mocker):
     assert isinstance(fut.exception, NotLeaderForPartitionError)
 
 
-def test_partition_records_offset():
-    """Test that compressed messagesets are handled correctly
-    when fetch offset is in the middle of the message list
-    """
-    batch_start = 120
-    batch_end = 130
-    fetch_offset = 123
-    tp = TopicPartition('foo', 0)
-    messages = [ConsumerRecord(tp.topic, tp.partition, i,
-                               None, None, 'key', 'value', 'checksum', 0, 0)
-                for i in range(batch_start, batch_end)]
-    records = Fetcher.PartitionRecords(fetch_offset, None, messages)
-    assert len(records) > 0
-    msgs = records.take(1)
-    assert msgs[0].offset == 123
-    assert records.fetch_offset == 124
-    msgs = records.take(2)
-    assert len(msgs) == 2
-    assert len(records) > 0
-    records.discard()
-    assert len(records) == 0
-
-
 def test_fetched_records(fetcher, topic, mocker):
     fetcher.config['check_crcs'] = False
     tp = TopicPartition(topic, 0)