文件变更

app/graph/graph_builder.py

@@ -0,0 +1,79 @@
+"""
+LangGraph 状态图构建模块 - 精简版，仅负责组装图
+所有节点逻辑已拆分到独立模块
+"""
+
+from langchain_core.language_models import BaseLLM
+from langgraph.graph import StateGraph, START, END
+
+# 本地模块
+from app.graph.state import MessagesState, GraphContext
+from app.nodes import (
+    create_llm_call_node,
+    create_tool_call_node,
+    create_retrieve_memory_node,
+    create_summarize_node,
+    should_continue
+)
+from app.memory import Mem0Client
+from app.nodes.finalize import finalize_node
+
+
+class GraphBuilder:
+    """LangGraph 状态图构建器 - 仅负责组装图"""
+
+    def __init__(self, llm: BaseLLM, tools: list, tools_by_name: dict):
+        """
+        初始化构建器
+        
+        Args:
+            llm: 大语言模型实例
+            tools: 工具列表
+            tools_by_name: 名称到工具函数的映射
+        """
+        self.llm = llm
+        self.tools = tools
+        self.tools_by_name = tools_by_name
+        
+        # ⭐ 创建 Mem0 客户端（懒加载，首次使用时初始化）
+        self.mem0_client = Mem0Client(llm)
+
+    def build(self) -> StateGraph:
+        """
+        构建未编译的状态图
+        
+        Returns:
+            StateGraph 实例
+        """
+        builder = StateGraph(MessagesState, context_schema=GraphContext)
+        
+        # ⭐ 通过工厂函数创建节点（依赖注入）
+        retrieve_memory_node = create_retrieve_memory_node(self.mem0_client)
+        llm_call_node = create_llm_call_node(self.llm, self.tools)
+        tool_call_node = create_tool_call_node(self.tools_by_name)
+        summarize_node = create_summarize_node(self.mem0_client)
+        
+        # 添加节点
+        builder.add_node("retrieve_memory", retrieve_memory_node)
+        builder.add_node("llm_call", llm_call_node)
+        builder.add_node("tool_node", tool_call_node)
+        builder.add_node("summarize", summarize_node)
+        builder.add_node("finalize", finalize_node)
+
+        # 添加边
+        builder.add_edge(START, "retrieve_memory")
+        builder.add_edge("retrieve_memory", "llm_call")
+        builder.add_conditional_edges(
+            "llm_call",
+            should_continue,
+            {
+                "tool_node": "tool_node",
+                "summarize": "summarize",
+                "finalize": "finalize"
+            }
+        )
+        builder.add_edge("tool_node", "llm_call")
+        builder.add_edge("summarize", "finalize")
+        builder.add_edge("finalize", END)
+        
+        return builder