feat: Add base project structure with API and web components

api/app/services/conversation_service.py

@@ -0,0 +1,229 @@
+"""会话服务"""
+import uuid
+from typing import Optional, List, Tuple
+from sqlalchemy.orm import Session
+from sqlalchemy import select, desc
+
+from app.models import Conversation, Message
+from app.core.exceptions import ResourceNotFoundException, BusinessException
+from app.core.error_codes import BizCode
+from app.core.logging_config import get_business_logger
+
+logger = get_business_logger()
+
+
+class ConversationService:
+    """会话服务"""
+    
+    def __init__(self, db: Session):
+        self.db = db
+    
+    def create_conversation(
+        self,
+        app_id: uuid.UUID,
+        workspace_id: uuid.UUID,
+        user_id: Optional[str] = None,
+        title: Optional[str] = None,
+        is_draft: bool = False,
+        config_snapshot: Optional[dict] = None
+    ) -> Conversation:
+        """创建会话"""
+        conversation = Conversation(
+            app_id=app_id,
+            workspace_id=workspace_id,
+            user_id=user_id,
+            title=title or "新会话",
+            is_draft=is_draft,
+            config_snapshot=config_snapshot
+        )
+        
+        self.db.add(conversation)
+        self.db.commit()
+        self.db.refresh(conversation)
+        
+        logger.info(
+            f"创建会话成功",
+            extra={
+                "conversation_id": str(conversation.id),
+                "app_id": str(app_id),
+                "workspace_id": str(workspace_id),
+                "is_draft": is_draft
+            }
+        )
+        
+        return conversation
+    
+    def get_conversation(
+        self,
+        conversation_id: uuid.UUID,
+        workspace_id: Optional[uuid.UUID] = None
+    ) -> Conversation:
+        """获取会话"""
+        stmt = select(Conversation).where(Conversation.id == conversation_id)
+        
+        if workspace_id:
+            stmt = stmt.where(Conversation.workspace_id == workspace_id)
+        
+        conversation = self.db.scalars(stmt).first()
+        
+        if not conversation:
+            raise ResourceNotFoundException("会话", str(conversation_id))
+        
+        return conversation
+    
+    def list_conversations(
+        self,
+        app_id: uuid.UUID,
+        workspace_id: uuid.UUID,
+        user_id: Optional[str] = None,
+        is_draft: Optional[bool] = None,
+        page: int = 1,
+        pagesize: int = 20
+    ) -> Tuple[List[Conversation], int]:
+        """列出会话"""
+        stmt = select(Conversation).where(
+            Conversation.app_id == app_id,
+            Conversation.workspace_id == workspace_id,
+            Conversation.is_active == True
+        )
+        
+        if user_id:
+            stmt = stmt.where(Conversation.user_id == user_id)
+        
+        if is_draft is not None:
+            stmt = stmt.where(Conversation.is_draft == is_draft)
+        
+        # 总数
+        count_stmt = stmt.with_only_columns(Conversation.id)
+        total = len(self.db.execute(count_stmt).all())
+        
+        # 分页
+        stmt = stmt.order_by(desc(Conversation.updated_at))
+        stmt = stmt.offset((page - 1) * pagesize).limit(pagesize)
+        
+        conversations = list(self.db.scalars(stmt).all())
+        
+        return conversations, total
+    
+    def add_message(
+        self,
+        conversation_id: uuid.UUID,
+        role: str,
+        content: str,
+        meta_data: Optional[dict] = None
+    ) -> Message:
+        """添加消息"""
+        message = Message(
+            conversation_id=conversation_id,
+            role=role,
+            content=content,
+            meta_data=meta_data
+        )
+        
+        self.db.add(message)
+        
+        # 更新会话的消息计数和更新时间
+        conversation = self.get_conversation(conversation_id)
+        conversation.message_count += 1
+        
+        # 如果是第一条用户消息，可以用它作为标题
+        if conversation.message_count == 1 and role == "user":
+            conversation.title = content[:50] + ("..." if len(content) > 50 else "")
+        
+        self.db.commit()
+        self.db.refresh(message)
+        
+        return message
+    
+    def get_messages(
+        self,
+        conversation_id: uuid.UUID,
+        limit: Optional[int] = None
+    ) -> List[Message]:
+        """获取会话消息"""
+        stmt = select(Message).where(
+            Message.conversation_id == conversation_id
+        ).order_by(Message.created_at)
+        
+        if limit:
+            stmt = stmt.limit(limit)
+        
+        messages = list(self.db.scalars(stmt).all())
+        
+        return messages
+    
+    def get_conversation_history(
+        self,
+        conversation_id: uuid.UUID,
+        max_history: Optional[int] = None
+    ) -> List[dict]:
+        """获取会话历史消息
+        
+        Args:
+            conversation_id: 会话ID
+            max_history: 最大历史消息数量
+            
+        Returns:
+            List[dict]: 历史消息列表，格式为 [{"role": "user", "content": "..."}, ...]
+        """
+        messages = self.get_messages(conversation_id, limit=max_history)
+        
+        # 转换为字典格式
+        history = [
+            {
+                "role": msg.role,
+                "content": msg.content
+            }
+            for msg in messages
+        ]
+        
+        return history
+    
+    def save_conversation_messages(
+        self,
+        conversation_id: uuid.UUID,
+        user_message: str,
+        assistant_message: str
+    ):
+        """保存会话消息（用户消息和助手回复）"""
+        # 添加用户消息
+        self.add_message(
+            conversation_id=conversation_id,
+            role="user",
+            content=user_message
+        )
+        
+        # 添加助手消息
+        self.add_message(
+            conversation_id=conversation_id,
+            role="assistant",
+            content=assistant_message
+        )
+        
+        logger.debug(
+            f"保存会话消息成功",
+            extra={
+                "conversation_id": str(conversation_id),
+                "user_message_length": len(user_message),
+                "assistant_message_length": len(assistant_message)
+            }
+        )
+    
+    def delete_conversation(
+        self,
+        conversation_id: uuid.UUID,
+        workspace_id: uuid.UUID
+    ):
+        """删除会话（软删除）"""
+        conversation = self.get_conversation(conversation_id, workspace_id)
+        conversation.is_active = False
+        
+        self.db.commit()
+        
+        logger.info(
+            f"删除会话成功",
+            extra={
+                "conversation_id": str(conversation_id),
+                "workspace_id": str(workspace_id)
+            }
+        )