From fdaa4cf7a48385e82806a787937cddf92c072db6 Mon Sep 17 00:00:00 2001
From: Ishaan Jaff <ishaan@berri.ai>
Date: Tue, 29 Sep 2026 22:59:13 -0700
Subject: [PATCH] test(agent-tracing): cover ClickHouseBatchLogger batching,
 backpressure, retry

---
 .../test_clickhouse_batch_logger.py           | 71 +++++++++++++++++++
 1 file changed, 71 insertions(+)
 create mode 100644 tests/test_litellm/integrations/clickhouse/test_clickhouse_batch_logger.py

diff --git a/tests/test_litellm/integrations/clickhouse/test_clickhouse_batch_logger.py b/tests/test_litellm/integrations/clickhouse/test_clickhouse_batch_logger.py
new file mode 100644
index 00000000000..c8ceed727b7
--- /dev/null
+++ b/tests/test_litellm/integrations/clickhouse/test_clickhouse_batch_logger.py
@@ -0,0 +1,71 @@
+"""
+Tests for the CustomBatchLogger-based ClickHouse base logger.
+"""
+
+import os
+import sys
+from unittest.mock import AsyncMock, MagicMock, patch
+
+sys.path.insert(0, os.path.abspath("../../.."))
+
+import pytest
+
+from litellm.integrations.clickhouse import clickhouse_batch_logger as module
+from litellm.integrations.clickhouse.clickhouse_batch_logger import ClickHouseBatchLogger
+from litellm.integrations.custom_batch_logger import CustomBatchLogger
+
+
+class _TestLogger(ClickHouseBatchLogger):
+    table = "test_table"
+
+
+def _logger(insert: AsyncMock) -> _TestLogger:
+    client = MagicMock()
+    client.insert_json_each_row = insert
+    return _TestLogger(client=client)
+
+
+def test_is_a_custom_batch_logger():
+    assert issubclass(ClickHouseBatchLogger, CustomBatchLogger)
+
+
+@pytest.mark.asyncio
+async def test_flush_splits_into_batches_and_empties_queue():
+    insert = AsyncMock()
+    logger = _logger(insert)
+    logger.batch_size = 2
+    logger.log_queue.extend([{"i": i} for i in range(5)])
+
+    await logger.flush_queue()
+
+    assert [len(c.args[1]) for c in insert.await_args_list] == [2, 2, 1]
+    assert all(c.args[0] == "test_table" for c in insert.await_args_list)
+    assert logger.log_queue == []
+    assert logger.rows_written == 5
+
+
+@pytest.mark.asyncio
+async def test_is_full_signals_backpressure():
+    logger = _logger(AsyncMock())
+    with patch.object(module, "CLICKHOUSE_MAX_BUFFERED_ROWS", 3):
+        logger.log_queue.extend([{}, {}])
+        assert logger.is_full() is False
+        logger.log_queue.append({})
+        assert logger.is_full() is True
+
+
+@pytest.mark.asyncio
+async def test_failed_insert_is_requeued_then_dropped():
+    insert = AsyncMock(side_effect=RuntimeError("clickhouse down"))
+    logger = _logger(insert)
+    logger.log_queue.extend([{"request_id": "a"}, {"request_id": "b"}])
+
+    with patch.object(module, "CLICKHOUSE_MAX_RETRIES", 2):
+        await logger.flush_queue()
+        assert len(logger.log_queue) == 2  # kept for retry
+        await logger.flush_queue()
+
+    assert insert.await_count == 2
+    assert logger.rows_dropped == 2
+    assert logger.rows_written == 0
+    assert logger.log_queue == []