From 36f1af83cc53c0e63791dc11d46e6b247314927e Mon Sep 17 00:00:00 2001
From: Yucheng Zhu <yucheng@berri.ai>
Date: Tue, 1 Sep 2026 12:30:07 -0700
Subject: [PATCH] fix(langfuse): normalize non-string observation ids

---
 litellm/integrations/langfuse/langfuse_sdk.py | 23 +++++++---------
 .../langfuse/test_langfuse_sdk.py             | 27 ++++++++++++++++++-
 2 files changed, 35 insertions(+), 15 deletions(-)

diff --git a/litellm/integrations/langfuse/langfuse_sdk.py b/litellm/integrations/langfuse/langfuse_sdk.py
index f3ad9ae57a6..7cd1d288f4b 100644
--- a/litellm/integrations/langfuse/langfuse_sdk.py
+++ b/litellm/integrations/langfuse/langfuse_sdk.py
@@ -54,25 +54,20 @@ def to_unix_nanos(value: datetime | float | None) -> int | None:
     return int(seconds * 1_000_000_000)
 
 
-def resolve_trace_id(trace_id: str | None) -> str:
-    """Map litellm's trace id onto the 32 lowercase hex characters v4 requires.
-
-    Anything else raises inside the SDK rather than being ignored, so a plain
-    uuid is dash-stripped and any other identifier is hashed deterministically,
-    which keeps repeat calls with the same id on the same trace.
-    """
-    normalized: Final = trace_id.lower().replace("-", "") if trace_id else ""
-    if _TRACE_ID_PATTERN.match(normalized):
+def resolve_trace_id(trace_id: object | None) -> str:
+    """Map a caller's trace id onto the 32 lowercase hex characters v4 requires."""
+    normalized: Final = "" if trace_id is None else str(trace_id).lower().replace("-", "")
+    if _TRACE_ID_PATTERN.fullmatch(normalized):
         return normalized
-    return Langfuse.create_trace_id(seed=trace_id) if trace_id else Langfuse.create_trace_id()
+    return Langfuse.create_trace_id(seed=str(trace_id)) if normalized else Langfuse.create_trace_id()
 
 
-def resolve_observation_id(observation_id: str | None) -> str | None:
-    """Same for a caller-supplied parent, which v4 requires to be 16 hex characters."""
-    normalized: Final = observation_id.lower().replace("-", "") if observation_id else ""
+def resolve_observation_id(observation_id: object | None) -> str | None:
+    """Map a caller's parent observation id onto v4's 16 lowercase hex characters."""
+    normalized: Final = "" if observation_id is None else str(observation_id).lower().replace("-", "")
     if not normalized:
         return None
-    if _OBSERVATION_ID_PATTERN.match(normalized):
+    if _OBSERVATION_ID_PATTERN.fullmatch(normalized):
         return normalized
     return sha256(normalized.encode("utf-8")).digest()[:8].hex()
 
diff --git a/tests/test_litellm/integrations/langfuse/test_langfuse_sdk.py b/tests/test_litellm/integrations/langfuse/test_langfuse_sdk.py
index 39cfeb2fff8..9cf2a6cb142 100644
--- a/tests/test_litellm/integrations/langfuse/test_langfuse_sdk.py
+++ b/tests/test_litellm/integrations/langfuse/test_langfuse_sdk.py
@@ -18,8 +18,8 @@ from opentelemetry.sdk.trace.export.in_memory_span_exporter import InMemorySpanE
 
 from litellm.integrations.langfuse.langfuse import (
     MINIMUM_LANGFUSE_VERSION,
-    raise_if_unsupported_langfuse_version,
     installed_langfuse_version,
+    raise_if_unsupported_langfuse_version,
 )
 from litellm.integrations.langfuse.langfuse_sdk import (
     AS_ROOT_ATTRIBUTE,
@@ -251,6 +251,31 @@ def test_arbitrary_trace_id_is_hashed_deterministically():
     assert first != resolve_trace_id("order-4472")
 
 
+@pytest.mark.parametrize("supplied", [12345, 12.5, True, False], ids=["int", "float", "true", "false"])
+def test_non_string_trace_id_is_normalized(supplied):
+    resolved = resolve_trace_id(supplied)
+
+    assert len(resolved) == 32
+    assert resolved == resolve_trace_id(supplied)
+
+
+@pytest.mark.parametrize("supplied", [12345, 12.5, True, False], ids=["int", "float", "true", "false"])
+def test_non_string_observation_id_is_normalized(supplied):
+    resolved = resolve_observation_id(supplied)
+
+    assert len(resolved) == 16
+    assert resolved == resolve_observation_id(supplied)
+
+
+def test_trace_id_with_trailing_newline_is_hashed():
+    supplied = "a" * 32 + "\n"
+
+    resolved = resolve_trace_id(supplied)
+
+    assert resolved != supplied
+    assert len(resolved) == 32
+
+
 def test_missing_trace_id_still_yields_a_valid_trace_id():
     generated = resolve_trace_id(None)
     assert len(generated) == 32