fix(jina): log transient failures at WARNING without traceback (#2484) (#2485)

The exception handler in JinaClient.crawl used logger.exception, which
emits an ERROR-level record with the full httpx/httpcore/anyio traceback
for every transient network failure (timeout, connection refused). Other
search/crawl providers in the project log the same class of recoverable
failures as a single line. One offline/slow-network session could produce
dozens of multi-frame ERROR stack traces, drowning out real problems.

Switch to logger.warning with a concise message that includes the
exception type and its str, matching the style used elsewhere for
recoverable transient failures (aio_sandbox, ddg, etc.). The exception
type now also surfaces into the returned "Error: ..." string so callers
retain diagnostic signal.

Adds a regression test that asserts the log record is WARNING, carries
no exc_info, and includes the exception class name.

Co-authored-by: voidborne-d <voidborne-d@users.noreply.github.com>
Co-authored-by: Willem Jiang <willem.jiang@gmail.com>

backend/packages/harness/deerflow/community/jina_ai/jina_client.py

@@ -38,6 +38,6 @@ class JinaClient:
 
             return response.text
         except Exception as e:
-            error_message = f"Request to Jina API failed: {str(e)}"
+            error_message = f"Request to Jina API failed: {type(e).__name__}: {e}"
-            logger.exception(error_message)
+            logger.warning(error_message)
             return f"Error: {error_message}"

backend/tests/test_jina_client.py

@@ -80,6 +80,28 @@ async def test_crawl_network_error(jina_client, monkeypatch):
     assert "failed" in result.lower()
 
 
+@pytest.mark.anyio
+async def test_crawl_transient_failure_logs_without_traceback(jina_client, monkeypatch, caplog):
+    """Transient network failures must log at WARNING without a traceback and include the exception type."""
+
+    async def mock_post(self, url, **kwargs):
+        raise httpx.ConnectTimeout("timed out")
+
+    monkeypatch.setattr(httpx.AsyncClient, "post", mock_post)
+
+    with caplog.at_level(logging.DEBUG, logger="deerflow.community.jina_ai.jina_client"):
+        result = await jina_client.crawl("https://example.com")
+
+    jina_records = [r for r in caplog.records if r.name == "deerflow.community.jina_ai.jina_client"]
+    assert len(jina_records) == 1, f"expected exactly one log record, got {len(jina_records)}"
+    record = jina_records[0]
+    assert record.levelno == logging.WARNING, f"expected WARNING, got {record.levelname}"
+    assert record.exc_info is None, "transient failures must not attach a traceback"
+    assert "ConnectTimeout" in record.getMessage()
+    assert result.startswith("Error:")
+    assert "ConnectTimeout" in result
+
+
 @pytest.mark.anyio
 async def test_crawl_passes_headers(jina_client, monkeypatch):
     """Test that correct headers are sent."""