From 84df4013a0f5e404d5c383c32c81cd94f478d431 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Eigil=20Skj=C3=A6veland?= <eigil@vipps.no>
Date: Thu, 20 Jun 2024 13:49:18 +0200
Subject: [PATCH] python client: Support empty lines

---
 python/zeroeventhub/tests/test_client.py   | 25 ++++++++++++++++++++++
 python/zeroeventhub/zeroeventhub/client.py |  2 ++
 2 files changed, 27 insertions(+)

diff --git a/python/zeroeventhub/tests/test_client.py b/python/zeroeventhub/tests/test_client.py
index 85cf474..eab7c60 100644
--- a/python/zeroeventhub/tests/test_client.py
+++ b/python/zeroeventhub/tests/test_client.py
@@ -311,6 +311,31 @@ async def test_fetch_events_succeeds_when_response_is_empty(
     mock_event_receiver.checkpoint.assert_not_called()
 
 
+async def test_fetch_events_succeeds_when_response_is_empty_line(
+    client, mock_event_receiver, respx_mock
+):
+    """Test that fetch_events gracefully handles an empty line in the response."""
+    # arrange
+    cursors = [Cursor(1, "cursor1"), Cursor(2, "cursor2")]
+    page_size_hint = 10
+    headers = None
+
+    respx_mock.get(client.url).mock(
+        return_value=httpx.Response(
+            status_code=204,
+            headers={"content_type": "application/x-ndjson"},
+            content="\n",
+        )
+    )
+
+    # act
+    await receive_events(mock_event_receiver, client.fetch_events(cursors, page_size_hint, headers))
+
+    # assert that the event and checkpoint methods were not called
+    mock_event_receiver.event.assert_not_called()
+    mock_event_receiver.checkpoint.assert_not_called()
+
+
 async def test_raises_error_when_response_contains_invalid_json_line(
     client, mock_event_receiver, respx_mock
 ):
diff --git a/python/zeroeventhub/zeroeventhub/client.py b/python/zeroeventhub/zeroeventhub/client.py
index 03904a0..fd4715e 100644
--- a/python/zeroeventhub/zeroeventhub/client.py
+++ b/python/zeroeventhub/zeroeventhub/client.py
@@ -119,6 +119,8 @@ async def _process_response(
         res.raise_for_status()
 
         async for line in aiter_lines(res, "\n"):
+            if not line:
+                continue
             yield self._parse_checkpoint_or_event(line)
 
     def _parse_checkpoint_or_event(self, raw_line: str) -> Union[Event, Cursor]: