Merge pull request #614 from vivek0369/codex/metadata-factory-exception-shielding

 Feature: Context-Aware Metadata Factory Exception Shielding

Author: param20h

backend/app/rag/tracing.py

@@ -87,7 +87,17 @@ def trace_function(
     def decorator(fn: Callable[..., Any]) -> Callable[..., Any]:
         @wraps(fn)
         def wrapped(*args: Any, **kwargs: Any) -> Any:
-            metadata = metadata_factory(*args, **kwargs) if metadata_factory else None
+            metadata = None
+            if metadata_factory:
+                try:
+                    metadata = metadata_factory(*args, **kwargs)
+                except Exception:
+                    logger.warning(
+                        "Metadata factory failed for trace %r; continuing without metadata.",
+                        name,
+                        exc_info=True,
+                    )
+                    metadata = {}
             return trace_call(
                 name,
                 fn,

backend/tests/test_tracing.py

@@ -0,0 +1,54 @@
+import logging
+
+from app.rag import tracing
+
+
+def test_trace_function_uses_metadata_factory(monkeypatch):
+    captured = {}
+
+    def fake_trace_call(name, fn, *args, run_type, metadata, **kwargs):
+        captured.update(name=name, run_type=run_type, metadata=metadata)
+        return fn(*args, **kwargs)
+
+    monkeypatch.setattr(tracing, "trace_call", fake_trace_call)
+
+    @tracing.trace_function(
+        "answer-question",
+        metadata_factory=lambda value: {"value": value},
+    )
+    def decorated(value):
+        return value.upper()
+
+    assert decorated("hello") == "HELLO"
+    assert captured == {
+        "name": "answer-question",
+        "run_type": "chain",
+        "metadata": {"value": "hello"},
+    }
+
+
+def test_trace_function_shields_metadata_factory_exceptions(monkeypatch, caplog):
+    captured = {}
+
+    def fake_trace_call(name, fn, *args, run_type, metadata, **kwargs):
+        captured["metadata"] = metadata
+        return fn(*args, **kwargs)
+
+    def failing_metadata_factory(value):
+        raise KeyError(value)
+
+    monkeypatch.setattr(tracing, "trace_call", fake_trace_call)
+
+    @tracing.trace_function(
+        "answer-question",
+        metadata_factory=failing_metadata_factory,
+    )
+    def decorated(value):
+        return value.upper()
+
+    with caplog.at_level(logging.WARNING, logger=tracing.__name__):
+        assert decorated("hello") == "HELLO"
+
+    assert captured["metadata"] == {}
+    assert "Metadata factory failed for trace 'answer-question'" in caplog.text
+    assert "KeyError: 'hello'" in caplog.text