feat:新增投顾agent和nl2sqlagent

nl2sql/session_context.py

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+"""NL2SQL 会话上下文的 Redis 存储与 Prompt 格式化。"""
+from __future__ import annotations
+
+import json
+import logging
+from typing import Any
+
+
+logger = logging.getLogger("nl2sql.session_context")
+
+
+class SessionContextStore:
+    """按员工隔离并限制大小的短期查询上下文。"""
+
+    def __init__(self, redis, *, ttl: int = 1800, max_messages: int = 8, max_chars: int = 4000):
+        self.redis = redis
+        self.ttl = ttl
+        self.max_messages = max_messages
+        self.max_chars = max_chars
+
+    def _key(self, session_id: str) -> str:
+        return f"nl2sql:session:{session_id}:context"
+
+    def _owner_key(self, session_id: str) -> str:
+        return f"nl2sql:session:{session_id}:owner"
+
+    async def _belongs_to(self, user_id: int, session_id: str) -> bool:
+        owner_key = self._owner_key(session_id)
+        owner = await self.redis.get(owner_key)
+        if owner is None:
+            return bool(await self.redis.set(owner_key, str(user_id), nx=True, ex=self.ttl))
+        if isinstance(owner, bytes):
+            owner = owner.decode()
+        return str(owner) == str(user_id)
+
+    async def load(self, user_id: int, session_id: str | None) -> list[dict[str, str]]:
+        """读取当前员工的上下文，异常或跨员工访问时返回空列表。"""
+        if not session_id:
+            return []
+        try:
+            if not await self._belongs_to(user_id, session_id):
+                return []
+            raw = await self.redis.get(self._key(session_id))
+            if not raw:
+                return []
+            if isinstance(raw, bytes):
+                raw = raw.decode()
+            value = json.loads(raw)
+            return value if isinstance(value, list) else []
+        except Exception:  # noqa: BLE001 上下文故障不阻断查询
+            logger.warning("NL2SQL 会话上下文读取失败", exc_info=True)
+            return []
+
+    async def append(self, user_id: int, session_id: str | None, question: str, status: str) -> bool:
+        """追加问题和状态摘要，不保存 SQL、结果行或敏感数据。"""
+        if not session_id:
+            return False
+        try:
+            if not await self._belongs_to(user_id, session_id):
+                return False
+            messages = await self.load(user_id, session_id)
+            messages.append({"role": "user", "content": question[:1000]})
+            messages.append({"role": "assistant", "content": status[:100]})
+            messages = messages[-self.max_messages :]
+            while len(json.dumps(messages, ensure_ascii=False)) > self.max_chars and messages:
+                messages.pop(0)
+            await self.redis.set(self._key(session_id), json.dumps(messages, ensure_ascii=False), ex=self.ttl)
+            return True
+        except Exception:  # noqa: BLE001 上下文故障不阻断查询
+            logger.warning("NL2SQL 会话上下文写入失败", exc_info=True)
+            return False
+
+
+def build_conversation_context(messages: list[dict[str, Any]], *, max_chars: int = 2000) -> str:
+    """构造有界 Prompt 上下文，只保留角色和文本内容。"""
+    lines: list[str] = []
+    for message in messages:
+        role = str(message.get("role", ""))[:20]
+        content = str(message.get("content", ""))[:500]
+        if role and content:
+            lines.append(f"{role}: {content}")
+    return "\n".join(lines)[-max_chars:]