Fix P0: llm log redaction (remove full prompt/response from logs) and session.py thread-safe atomic writes

backend/llm.py

@@ -35,7 +35,6 @@ class _LLMLoggingWrapper(_BaseLLM):
     def invoke(self, prompt: str) -> Any:
         t0 = time.time()
         prompt_len = len(prompt)
-        prompt_preview = prompt[:500]
         _llm_log.debug(
             "LLM invoke 请求",
             extra={
@@ -44,8 +43,7 @@ class _LLMLoggingWrapper(_BaseLLM):
                 "backend": self._backend,
                 "caller": self._caller,
                 "prompt_length": prompt_len,
-                "prompt_preview": prompt_preview,
-                "prompt": prompt[:10000],
+                "prompt_preview": prompt[:500],
             },
         )
         try:
@@ -64,7 +62,6 @@ class _LLMLoggingWrapper(_BaseLLM):
                     "duration_ms": elapsed,
                     "response_length": resp_len,
                     "response_preview": resp_preview,
-                    "response": content[:10000],
                 },
             )
             return result
@@ -79,7 +76,7 @@ class _LLMLoggingWrapper(_BaseLLM):
                     "caller": self._caller,
                     "duration_ms": elapsed,
                     "error": str(e),
-                    "prompt": prompt[:10000],
+                    "prompt_preview": prompt[:500],
                 },
             )
             raise
@@ -96,8 +93,7 @@ class _LLMLoggingWrapper(_BaseLLM):
                 "backend": self._backend,
                 "caller": self._caller,
                 "prompt_length": prompt_len,
-                "prompt_preview": prompt_preview,
-                "prompt": prompt[:10000],
+                "prompt_preview": prompt[:500],
             },
         )
         full = []
@@ -135,7 +131,6 @@ class _LLMLoggingWrapper(_BaseLLM):
                         "duration_ms": elapsed,
                         "response_length": resp_len,
                         "response_preview": resp_preview,
-                        "response": resp_text[:10000],
                         "stop_reason": stop_reason,
                     },
                 )
@@ -150,7 +145,7 @@ class _LLMLoggingWrapper(_BaseLLM):
                     "caller": self._caller,
                     "duration_ms": elapsed,
                     "error": str(e),
-                    "prompt": prompt[:10000],
+                    "prompt_preview": prompt[:500],
                 },
             )
             raise

backend/session.py

@@ -6,11 +6,50 @@
 import json
 import os
 import re
+import threading
 import uuid
 import tempfile
 from datetime import datetime, timezone
 from pathlib import Path
-from typing import Optional
+from typing import Optional, Any
+
+# Per-session-file locks to prevent concurrent writes from corrupting JSON
+_session_locks: dict[str, threading.Lock] = {}
+_locks_lock = threading.Lock()
+
+def _get_lock(session_id: str) -> threading.Lock:
+    with _locks_lock:
+        if session_id not in _session_locks:
+            _session_locks[session_id] = threading.Lock()
+        return _session_locks[session_id]
+
+
+class _SafeEncoder(json.JSONEncoder):
+    """处理 numpy / lxml / 等非标准类型的 JSON 序列化"""
+
+    def default(self, o: Any) -> Any:
+        try:
+            # numpy 标量
+            import numpy as np
+            if isinstance(o, np.integer):
+                return int(o)
+            if isinstance(o, np.floating):
+                return float(o)
+            if isinstance(o, np.ndarray):
+                return o.tolist()
+            if isinstance(o, np.bool_):
+                return bool(o)
+        except ImportError:
+            pass
+        # lxml intc / 其他 C 类型
+        try:
+            return int(o)
+        except Exception:
+            pass
+        # bytes
+        if isinstance(o, bytes):
+            return o.decode("utf-8", errors="replace")
+        return super().default(o)
 
 from dotenv import load_dotenv
 
@@ -59,8 +98,21 @@ def create_session(name: str = "", agent_state: Optional[dict] = None,
         "kb_id": agent_state.get("kb_id", "") if agent_state else "",
         "agent_state": agent_state,
     }
-    with open(_session_path(sid), "w", encoding="utf-8") as f:
-        json.dump(data, f, ensure_ascii=False, indent=2)
+    fp = _session_path(sid)
+    tmp = tempfile.NamedTemporaryFile(
+        mode="w", suffix=".json", delete=False,
+        dir=SESSIONS_DIR, encoding="utf-8",
+    )
+    try:
+        json.dump(data, tmp, ensure_ascii=False, indent=2, cls=_SafeEncoder)
+        tmp.flush()
+        os.fsync(tmp.fileno())
+        tmp.close()
+        os.replace(tmp.name, str(fp))
+    except Exception:
+        tmp.close()
+        Path(tmp.name).unlink(missing_ok=True)
+        raise
     _session_log.info("创建会话", extra={"session_id": sid, "session_name": data["session_name"]})
     return data
 
@@ -79,9 +131,11 @@ def load_session(session_id: str) -> Optional[dict]:
 
 
 def save_session(session_id: str, agent_state: dict, session_name: str = ""):
-    """将会话状态原子保存至磁盘（temp file + rename，避免崩溃时截断）。"""
+    """线程安全地原子保存会话状态到磁盘。"""
     _ensure_dir()
     fp = _session_path(session_id)
+    lock = _get_lock(session_id)
+    with lock:
         data = {}
         if fp.exists():
             with open(fp, "r", encoding="utf-8") as f:
@@ -103,7 +157,7 @@ def save_session(session_id: str, agent_state: dict, session_name: str = ""):
             dir=SESSIONS_DIR, encoding="utf-8",
         )
         try:
-        json.dump(data, tmp, ensure_ascii=False, indent=2)
+            json.dump(data, tmp, ensure_ascii=False, indent=2, cls=_SafeEncoder)
             tmp.flush()
             os.fsync(tmp.fileno())
             tmp.close()