feat: add langfuse

backend/app/trace/attributes.py

@@ -0,0 +1,65 @@
+from __future__ import annotations
+
+from typing import Any, Dict, Mapping, Optional
+
+
+def sanitize_attributes(attributes: Optional[Mapping[str, Any]]) -> Dict[str, Any]:
+    if not attributes:
+        return {}
+    normalized: Dict[str, Any] = {}
+    for key, value in attributes.items():
+        if value is None:
+            continue
+        name = str(key).strip()
+        if not name:
+            continue
+        if isinstance(value, (str, int, float, bool)):
+            normalized[name] = value
+            continue
+        normalized[name] = str(value)
+    return normalized
+
+
+def build_chat_trace_attributes(
+    *,
+    session_id: str,
+    project_id: Optional[int],
+    model_id: Optional[str],
+    route_mode: str,
+    source: str,
+    knowledge_base_id: Optional[str],
+) -> Dict[str, Any]:
+    return sanitize_attributes(
+        {
+            "session_id": session_id,
+            "project_id": project_id,
+            "model_id": model_id,
+            "route_mode": route_mode,
+            "source": source,
+            "knowledge_base_id": knowledge_base_id,
+            "component": "chat_stream",
+        }
+    )
+
+
+def build_usage_attributes(usage: Optional[Mapping[str, Any]]) -> Dict[str, Any]:
+    if not usage:
+        return {}
+    return sanitize_attributes(
+        {
+            "usage.prompt_tokens": usage.get("prompt_tokens"),
+            "usage.completion_tokens": usage.get("completion_tokens"),
+            "usage.total_tokens": usage.get("total_tokens"),
+        }
+    )
+
+
+def build_error_attributes(exc: Exception, *, stage: str) -> Dict[str, Any]:
+    return sanitize_attributes(
+        {
+            "error": True,
+            "error.stage": stage,
+            "error.type": exc.__class__.__name__,
+            "error.message": str(exc),
+        }
+    )