feat(memory): replace Mem0 with local RAG using SQLite, ChromaDB, and bge-small

api/chat_service.py

@@ -13,7 +13,7 @@ from config import (
     MEM0_CONFIG,
 )
 from api.doubao_tts import text_to_speech
-from memory_module.memory_integration import Mem0Integration
+from memory_module import LocalMemoryIntegration
 
 logger = logging.getLogger(__name__)
 
@@ -21,7 +21,7 @@ logger = logging.getLogger(__name__)
 class ChatService:
     def __init__(self, user_id: str = None):
         self.user_id = user_id or DEFAULT_USER_ID
-        self.mem0_integration = Mem0Integration(MEM0_CONFIG)
+        self.mem0_integration = LocalMemoryIntegration(MEM0_CONFIG) # 使用新类
         self._initialized = False
     
     def initialize(self):

memory_module/__init__.py

@@ -1,3 +1,3 @@
-from .memory_integration import Mem0Integration
+from .memory_integration import LocalMemoryIntegration
 
-__all__ = ["Mem0Integration"]
+__all__ = ["LocalMemoryIntegration"]

memory_module/memory_integration.py

@@ -1,32 +1,47 @@
 import os
+import sqlite3
+import chromadb
+from sentence_transformers import SentenceTransformer
 from typing import List, Dict, Any, Optional
 from datetime import datetime
 import json
-import openai
+import openai  # 我们仍然需要它来调用 豆包LLM
 import threading
-from mem0 import Memory
 import logging
 import textwrap
 
+# 使用你项目中的日志配置
 logger = logging.getLogger(__name__)
 
 
-class Mem0Integration:
+class LocalMemoryIntegration:
-    """Mem0 integration for memory retrieval and storage in RAG pipeline."""
+    """
+    使用本地轻量级 RAG (SQLite + ChromaDB + bge-small) 替换 Mem0。
+    
+    它保留了原始的 LLM 调用和复杂的 JSON Prompt 逻辑，
+    只将 RAG 检索和存储部分本地化。
+    """
     
     def __init__(self, config: Dict[str, Any]):
-        """Initialize Mem0 with configuration."""
+        """
+        初始化本地记忆模块和 OpenAI (豆包) 客户端。
+        """
         self.config = config
-        self.memory = Memory.from_config(config)
         
-        # Initialize OpenAI client for chat completion
+        # 1. 初始化 LLM 客户端 (豆包) - 这部分逻辑保留
+        # config["llm"] 对应你 README 中的 LLM 配置
+        try:
             self.openai_client = openai.OpenAI(
                 api_key=config["llm"]["config"]["api_key"],
                 base_url=config["llm"]["config"].get("openai_base_url")
             )
             self.llm_model = config["llm"]["config"]["model"]
+            logger.info(f"OpenAI (Doubao) LLM client initialized for model: {self.llm_model}")
+        except KeyError as e:
+            logger.error(f"LLM config missing key: {e}. Check your MEM0_CONFIG['llm'].")
+            raise
             
-        # System prompt template aligned with virtual persona requirements
+        # 2. 保留核心的 System Prompt (从你发的文件中完整复制)
         self.system_prompt_template = textwrap.dedent("""
             你是虚拟人对话引擎。
 
@@ -106,7 +121,7 @@ class Mem0Integration:
 
             * **生气**（惹得虚拟人生气）：回复时情绪带有生气/气死/离谱/无语/滚/别烦，动作触发"不满"
 
-            * **否定**：不/并不/没那么 + 情绪词 → 降级或改判    动作触发"摇头"
+            * **否定**：不/并不/没那么 + 情绪词 → 降级或改判    动作触发"摇头"
 
             肯定：是/没错/肯定的+判断实时情绪，动作触发"点头"
 
@@ -173,50 +188,164 @@ class Mem0Integration:
             ```
         """).strip()
 
-    def search_memories(self, query: str, user_id: str, limit: int = 5) -> List[Any]:
+        # 3. 初始化本地 SQLite (存储原始文本)
-        """Search for relevant memories about the user."""
+        db_path = os.getenv('SQLITE_DB_PATH', 'local_memory.db')
+        self.db_conn = sqlite3.connect(db_path, check_same_thread=False)
+        self.db_conn.execute("""
+            CREATE TABLE IF NOT EXISTS memories (
+                id INTEGER PRIMARY KEY AUTOINCREMENT,
+                user_id TEXT NOT NULL,
+                role TEXT NOT NULL,
+                content TEXT NOT NULL,
+                chroma_id TEXT NOT NULL UNIQUE,
+                timestamp TEXT NOT NULL
+            );
+        """)
+        self.db_conn.execute("CREATE INDEX IF NOT EXISTS idx_user_id ON memories (user_id);")
+        logger.info(f"SQLite database initialized at {db_path}")
+
+        # 4. 初始化本地 ChromaDB (存储向量)
+        chroma_path = os.getenv('CHROMA_DB_PATH', './chroma_db_store')
+        self.chroma_client = chromadb.PersistentClient(path=chroma_path)
+        logger.info(f"ChromaDB persistent client initialized at {chroma_path}")
+
+        # 5. 初始化本地 Embedding 模型 (低内存占用)
+        model_name = 'bge-small-zh-v1.5' # 约 100MB 内存
         try:
-            results = self.memory.search(
+            logger.info(f"Loading local embedding model: {model_name}...")
-                query=query,
+            self.embedding_model = SentenceTransformer(model_name, device='cpu')
-                user_id=user_id,
+            logger.info("Local embedding model loaded successfully.")
-                limit=limit
-            )
-            # Handle dictionary response format - check for both 'memories' and 'results' keys
-            if isinstance(results, dict):
-                memories = results.get("memories", results.get("results", []))
-                return memories
-            else:
-                logger.error(f"Unexpected search results format: {type(results)}")
-                return []
         except Exception as e:
-            logger.error(f"Failed to search memories: {e}")
+            logger.error(f"Failed to load embedding model '{model_name}': {e}")
+            raise
+
+    def _get_user_collection(self, user_id: str):
+        """获取或创建该用户的 ChromaDB 集合"""
+        collection_name = f"user_memory_{user_id.replace('-', '_')}" # 确保 user_id 
+        return self.chroma_client.get_or_create_collection(name=collection_name)
+
+    def _get_max_id(self, user_id: str):
+        """获取该用户当前最大的 memory ID"""
+        try:
+            cursor = self.db_conn.execute("SELECT MAX(id) FROM memories WHERE user_id = ?", (user_id,))
+            max_id = cursor.fetchone()[0]
+            return max_id if max_id is not None else 0
+        except Exception as e:
+            logger.error(f"Failed to get max id from SQLite for user {user_id}: {e}")
+            return 0
+
+    # --- 实现 Mem0Integration 的公共接口 ---
+
+    def search_memories(self, query: str, user_id: str, limit: int = 5) -> List[Any]:
+        """
+        (本地实现) 搜索相关记忆。
+        返回一个字典列表，模仿 mem0 的输出格式。
+        """
+        logger.debug(f"Searching local memories for user {user_id} with query: {query}")
+        try:
+            collection = self._get_user_collection(user_id)
+            if collection.count() == 0:
+                logger.debug("No memories found for this user.")
+                return []
+                
+            # 1. 本地向量化查询
+            query_embedding = self.embedding_model.encode(query).tolist()
+            
+            # 2. 本地 ChromaDB (KNN) 搜索
+            results = collection.query(
+                query_embeddings=[query_embedding],
+                n_results=min(limit, collection.count()) # 确保 n_results 不超过集合大小
+            )
+            
+            # 3. 格式化为原函数期望的格式
+            formatted_results = []
+            if results and 'metadatas' in results and 'documents' in results:
+                for doc, meta in zip(results['documents'][0], results['metadatas'][0]):
+                    formatted_results.append({
+                        "memory": doc, # format_memories_for_prompt 会用这个 key
+                        "content": meta.get("content", doc), # 备用
+                        "role": meta.get("role", "unknown")
+                    })
+            
+            logger.debug(f"Found {len(formatted_results)} local memories.")
+            return formatted_results
+            
+        except Exception as e:
+            logger.error(f"Failed to search local memories: {e}")
             return []
 
     def add_memory(self, messages: List[Dict[str, str]], user_id: str, metadata: Optional[Dict] = None) -> Dict[str, Any]:
-        """Add a memory for the user."""
+        """(本地实现) 添加新的记忆。"""
-        try:
+        logger.debug(f"Adding local memory for user {user_id}")
-            # Debug: Log what we're trying to add
+        if metadata is None:
-            logger.debug(f"Adding memory for user {user_id}")
+            metadata = {}
-            logger.debug(f"Messages: {messages}")
-            logger.debug(f"Metadata: {metadata}")
             
-            result = self.memory.add(
+        try:
-                messages=messages,
+            collection = self._get_user_collection(user_id)
-                user_id=user_id,
+            
-                metadata=metadata or {},
+            texts_to_embed = []
-                infer= False
+            docs_to_store = []
+            metadatas_to_store = []
+            ids_to_store = []
+            
+            current_max_id = self._get_max_id(user_id)
+            
+            for i, msg in enumerate(messages):
+                role = msg.get("role")
+                content = msg.get("content")
+                if not role or not content:
+                    continue
+                
+                current_max_id += 1
+                chroma_id = f"mem_{user_id}_{current_max_id}"
+                timestamp = metadata.get("timestamp", datetime.now().isoformat())
+                
+                # 1. 存入 SQLite
+                self.db_conn.execute(
+                    "INSERT INTO memories (user_id, role, content, chroma_id, timestamp) VALUES (?, ?, ?, ?, ?)",
+                    (user_id, role, content, chroma_id, timestamp)
                 )
                 
-            # Debug: Log the result
+                # 2. 准备存入 ChromaDB
-            logger.debug(f"Add memory result: {result}")
+                full_text = f"{role}: {content}" # 向量化的文本
-            return result
+                texts_to_embed.append(full_text)
+                docs_to_store.append(full_text) # 存在 chroma 的 document 字段
+                metadatas_to_store.append({ # 存在 chroma 的 metadata 字段
+                    "role": role,
+                    "content": content, # 存一份原始内容
+                    "timestamp": timestamp
+                })
+                ids_to_store.append(chroma_id)
+                
+            if not texts_to_embed:
+                return {"success": True, "message": "No valid messages to add."}
+            
+            embeddings = self.embedding_model.encode(
+                texts_to_embed, 
+                batch_size=8
+            ).tolist()
+            
+            # 3. 批量存入 ChromaDB
+            collection.add(
+                embeddings=embeddings,
+                documents=docs_to_store,
+                metadatas=metadatas_to_store,
+                ids=ids_to_store
+            )
+            
+            self.db_conn.commit()
+            logger.debug(f"Successfully added {len(texts_to_embed)} local memories.")
+            return {"success": True, "message": f"Added {len(texts_to_embed)} memories."}
+            
         except Exception as e:
-            logger.error(f"Failed to add memory: {e}")
+            logger.error(f"Error in add_memory (local): {e}")
-            logger.exception("Exception details:")
+            self.db_conn.rollback()
-            return {}
+            return {"success": False, "error": str(e)}
+    
+    # --- 保留你原有的辅助函数和核心逻辑 ---
 
     def _extract_reply_for_memory(self, assistant_response: Any) -> str:
-        """Extract the assistant reply text from structured responses for memory storage."""
+        """(原样保留) 从结构化响应中提取用于记忆的助手回复文本。"""
         if assistant_response is None:
             return ""
 
@@ -228,21 +357,32 @@ class Mem0Integration:
             return ""
 
         try:
+            # 尝试解析 JSON, 兼容你 `chat_service` 可能遇到的 "```json\n{...}\n```"
+            if raw_text.startswith("```json"):
+                raw_text = raw_text.split("```json\n", 1)[-1].split("\n```")[0]
+                
             data = json.loads(raw_text)
             reply = data.get("reply", "")
             reply_str = str(reply).strip()
+            # 如果 'reply' 为空，也返回原始文本，以防 LLM 返回了非 JSON 格式的有效回复
             return reply_str if reply_str else raw_text 
         except Exception:
+             # 如果解析失败，返回原始文本
             return raw_text
 
     def format_memories_for_prompt(self, memories: List[Any]) -> str:
-        """Format memories into bullet points for injection into the system prompt."""
+        """
+        (轻微修改) 将记忆格式化为项目符号点，以便注入系统提示。
+        严格遵守 Prompt 中的 "MEM_INJECT_TOPK: 1–2 条" 规则。
+        """
         if not memories:
             return ""
 
         formatted = []
-        for memory in memories:
+        # 只取最相关的 2 条
+        for memory in memories[:2]: 
             if isinstance(memory, dict):
+                # 我们的 search_memories 返回 'memory' 键
                 memory_text = memory.get("memory") or memory.get("content") or ""
             elif isinstance(memory, str):
                 memory_text = memory
@@ -256,17 +396,20 @@ class Mem0Integration:
         return "\n".join(formatted)
     
     def generate_response_with_memory(self, user_input: str, user_id: str) -> Dict[str, Any]:
-        """Generate a response using memories and store the interaction."""
+        """
-        # Step 1: Search for relevant memories
+        (逻辑保留，调用本地) 使用记忆生成响应并存储交互。
+        """
+        # 步骤 1: 搜索相关记忆 (调用我们的本地搜索)
+        # Prompt 建议 1-2 条，我们搜 5 条，format_memories_for_prompt 会帮我们筛选
         memories = self.search_memories(user_input, user_id, limit=5) 
 
-        # Step 2: Prepare system prompt with memory injection
+        # 步骤 2: 准备系统提示 (逻辑保留)
         memory_block = self.format_memories_for_prompt(memories)
         system_prompt = self.system_prompt_template.replace(
             "{memory_block}", memory_block if memory_block else ""
         ).strip()
 
-        # Step 3: Generate response using OpenAI
+        # 步骤 3: 生成响应 (逻辑保留 - 仍然调用豆包 LLM)
         try:
             response = self.openai_client.chat.completions.create(
                 model=self.llm_model,
@@ -274,92 +417,112 @@ class Mem0Integration:
                     {"role": "system", "content": system_prompt},
                     {"role": "user", "content": user_input}
                 ],
-                reasoning_effort="minimal",
+                # reasoning_effort="minimal", # 你原始代码里的，如果豆包不支持就删掉
+                # 推荐开启 JSON 模式，让豆包强制输出 JSON
+                response_format={"type": "json_object"} 
             )
             
             assistant_response = response.choices[0].message.content
             reply_for_memory = self._extract_reply_for_memory(assistant_response)
-            if not reply_for_memory:
+            if not reply_for_memory: # 确保不存空记忆
                 reply_for_memory = assistant_response
             
-            # Step 5: Store the interaction as new memories (异步执行)
+            # 步骤 5: 异步存储交互 (逻辑保留 - 调用我们的本地 add_memory)
             messages = [
                 {"role": "user", "content": user_input},
-                {"role": "assistant", "content": reply_for_memory}
+                {"role": "assistant", "content": reply_for_memory} # 只存回复文本
             ]
-            
-            # Store with metadata including timestamp
             metadata = {
                 "timestamp": datetime.now().isoformat(),
                 "type": "chat_interaction"
             }
             
-            # 异步存储记忆，不阻塞主流程
+            # (原样保留) 启动异步线程存储记忆
             def store_memory_async():
                 try:
                     self.add_memory(messages, user_id, metadata)
                 except Exception as e:
-                    print(f"[WARNING] Async memory storage failed: {e}")
+                    # 原代码是 print, 统一用 logger
+                    logger.warning(f"[WARNING] Async local memory storage failed: {e}") 
             
-            # 启动异步线程存储记忆
             memory_thread = threading.Thread(target=store_memory_async, daemon=True)
             memory_thread.start()
             
             return {
                 "success": True,
-                "response": assistant_response,
+                "response": assistant_response, # 返回完整的 JSON 字符串给 chat_service
                 "user_id": user_id
             }
             
         except Exception as e:
-            print(f"[ERROR] Failed to generate response: {e}")
+            logger.error(f"[ERROR] Failed to generate response: {e}")
             return {
                 "success": False,
                 "error": str(e),
                 "user_id": user_id
             }
     
+    # --- 其他辅助 API 的本地实现 ---
+    
     def get_all_memories(self, user_id: str) -> List[Any]:
-        """Get all memories for a user."""
+        """(本地实现) 从 SQLite 获取所有原始文本历史"""
+        logger.debug(f"Getting all local memories for user {user_id}")
         try:
-            memories = self.memory.get_all(user_id=user_id)
+            cursor = self.db_conn.execute(
-            # Handle dictionary response format
+                "SELECT id, role, content, timestamp, chroma_id FROM memories WHERE user_id = ? ORDER BY id ASC",
-            if isinstance(memories, dict):
+                (user_id,)
-                # Check for different possible key names
+            )
-                if "memories" in memories:
+            return [{
-                    memories_list = memories.get("memories", [])
+                "id": row[4], # 返回 chroma_id 作为唯一标识符
-                elif "results" in memories:
+                "sqlite_id": row[0],
-                    memories_list = memories.get("results", [])
+                "memory": f"{row[1]}: {row[2]}",
-                else:
+                "role": row[1],
-                    # Try to find any list in the dict
+                "content": row[2],
-                    for key, value in memories.items():
+                "timestamp": row[3]
-                        if isinstance(value, list):
+            } for row in cursor.fetchall()]
-                            memories_list = value
-                            break
-                    else:
-                        memories_list = []
-                return memories_list
-            else:
-                print(f"[ERROR] Unexpected memories format: {type(memories)}")
-                return []
         except Exception as e:
-            print(f"[ERROR] Failed to get all memories: {e}")
+            logger.error(f"Error in get_all_memories (local): {e}")
             return []
 
     def delete_memory(self, memory_id: str) -> bool:
-        """Delete a specific memory."""
+        """(本地实现) 删除特定记忆 (memory_id 应该是 chroma_id)"""
+        logger.debug(f"Deleting local memory: {memory_id}")
         try:
-            self.memory.delete(memory_id)
+            # 1. 从 SQLite 删除
+            cursor = self.db_conn.execute("SELECT user_id FROM memories WHERE chroma_id = ?", (memory_id,))
+            row = cursor.fetchone()
+            if not row:
+                logger.warning(f"Memory ID {memory_id} not found in SQLite.")
+                return False
+            
+            user_id = row[0]
+            self.db_conn.execute("DELETE FROM memories WHERE chroma_id = ?", (memory_id,))
+            
+            # 2. 从 ChromaDB 删除
+            collection = self._get_user_collection(user_id)
+            collection.delete(ids=[memory_id])
+                
+            self.db_conn.commit()
             return True
         except Exception as e:
-            print(f"[ERROR] Failed to delete memory: {e}")
+            logger.error(f"Failed to delete memory (local): {e}")
+            self.db_conn.rollback()
             return False
     
     def delete_all_memories(self, user_id: str) -> bool:
-        """Delete all memories for a user."""
+        """(本地实现) 删除用户的所有记忆"""
+        logger.debug(f"Deleting all local memories for user {user_id}")
         try:
-            self.memory.delete_all(user_id=user_id)
+            # 1. 从 SQLite 删除
+            self.db_conn.execute("DELETE FROM memories WHERE user_id = ?", (user_id,))
+            self.db_conn.commit()
+            
+            # 2. 从 ChromaDB 删除 (删除整个 collection)
+            collection_name = f"user_memory_{user_id.replace('-', '_')}"
+            self.chroma_client.delete_collection(name=collection_name)
+            
             return True
         except Exception as e:
-            print(f"[ERROR] Failed to delete all memories: {e}")
+            logger.error(f"Failed to delete all memories (local): {e}")
+            self.db_conn.rollback()
             return False

pyproject.toml

@@ -5,6 +5,7 @@ description = "Add your description here"
 readme = "README.md"
 requires-python = ">=3.10"
 dependencies = [
+    "chromadb>=1.3.5",
     "fastapi>=0.115.12",
     "haystack-ai>=2.12.1",
     "huggingface-hub>=0.30.2",
@@ -12,6 +13,7 @@ dependencies = [
     "milvus-haystack>=0.0.15",
     "pydantic>=2.11.3",
     "pymilvus>=2.5.6",
+    "sentence-transformers>=5.1.2",
     "uvicorn>=0.34.0",
 ]
 [[tool.uv.index]]