feat: init project

2025-08-21 22:38:41 +08:00
commit 6ae03985bd
48 changed files with 7221 additions and 0 deletions
@@ -0,0 +1,192 @@
+import json
+from operator import add
+from typing import TypedDict, Annotated, List, Literal
+
+from fastapi import FastAPI
+from langchain_core.runnables import RunnableConfig
+from langgraph.checkpoint.postgres.aio import AsyncPostgresSaver
+from langgraph.constants import START, END
+from langgraph.graph import StateGraph
+from langgraph.graph.state import CompiledStateGraph
+from langgraph.types import interrupt, Command
+from sqlalchemy.orm.sync import update
+
+from app.model.LgApprove import LgApprove, LgApproveService
+from app.model.LgMessage import LgMessageService
+from app.utils.db_utils import AsyncSessionDep
+from app.utils.next_id import next_id
+from app.utils.postgres_checkpointer import AsyncPostgresSaverDep
+
+
+def add_langgraph_approve_route(app: FastAPI):
+  # 提交审批单/创建报销单
+  @app.post("/lg_approve/submit")
+  async def lg_approve_submit(
+    row_dict: dict,
+    checkpointer: AsyncPostgresSaverDep,
+    session: AsyncSessionDep,
+  ):
+    thread_id = await next_id()
+    graph = create_graph(checkpointer=checkpointer, session=session)
+    config = {"configurable": {"thread_id": thread_id}}
+    graph_state = await graph.ainvoke({"input_remarks": row_dict.get('remarks')}, config=config)
+    print(graph_state)
+    return graph_state
+
+  @app.get("/lg_message/feedback/{thread_id}/{approve_flag}")
+  async def lg_message_feedback(
+    thread_id: str,
+    approve_flag: str,
+    checkpointer: AsyncPostgresSaverDep,
+    session: AsyncSessionDep,
+  ):
+    graph = create_graph(checkpointer=checkpointer, session=session)
+    config = {"configurable": {"thread_id": thread_id}}
+    return await graph.ainvoke(Command(resume=approve_flag), config=config)
+
+
+def create_graph(
+  checkpointer: AsyncPostgresSaver,
+  session: AsyncSessionDep,
+) -> CompiledStateGraph:
+  class ApproveSchema(TypedDict):
+    id: str
+    remarks: str
+    status: str
+    result_content: str
+
+  class StateSchema(TypedDict):
+    # 图的入参，需要一个报销单的备注信息，实际业务场景中，入参起码还需要有报销单申请人的id，报销类型，报销金额，发票信息等等；
+    input_remarks: str
+    # 报销单由图中的节点来创建，插入到数据库
+    approve: ApproveSchema
+    # 图执行的结果标识，成功还是失败
+    approve_flag: bool
+    # 每个节点执行的日志信息可以塞到这个字符串数组中
+    log_list: Annotated[List[str], add]
+    # 执行图的时候，如果往消息表中插入了消息数据，也把这个插入的消息记录到状态中
+    lg_message_list: Annotated[List[dict], add]
+
+  builder = StateGraph(StateSchema)
+
+  # 创建报销单（审批单）
+  async def node_create_approve(state: StateSchema):
+    insert_approve_dict = {
+      "status": "pending_approval",
+      "result_content": '待审批......',
+      "remarks": state.get('input_remarks'),
+    }
+    insert_approve_cls = await LgApproveService.item_insert(session=session, row_dict=insert_approve_dict)
+    return {
+      "approve": insert_approve_cls.model_dump(),
+      "log_list": [f"node_create_approve：创建报销单[{insert_approve_cls.id}]"]
+    }
+
+  # 创建消息（提示用户审批）
+  async def node_create_message(state: StateSchema, config: RunnableConfig):
+    thread_id = config.get('configurable').get('thread_id')
+
+    insert_message_dict = {
+      "title": "您有一条报销单待审批。",
+      "content": f"您的下属员工「XXX」提交了一份报销单，报销内容为：{state.get('approve').get('remarks')}",
+      "status": "pending",
+      "render_configs": json.dumps([
+        {
+          "type": "button",
+          "data": {
+            "label": "审批通过",
+            "type": "primary",
+            "submit_url": f"/lg_message/feedback/{thread_id}/Y",
+          }
+        },
+        {
+          "type": "button",
+          "data": {
+            "label": "审批拒绝",
+            "submit_url": f"/lg_message/feedback/{thread_id}/N",
+          }
+        },
+      ], ensure_ascii=False),
+    }
+
+    insert_message_cls = await LgMessageService.item_insert(session=session, row_dict=insert_message_dict)
+
+    return {
+      "log_list": [f"node_create_message：创建审批消息，待商机主管「XXX」审批"],
+      "lg_message_list": [insert_message_cls.model_dump()],
+    }
+
+  # 触发中断（等待审批恢复重新执行这个节点）
+  async def node_wait_for_approve(state: StateSchema) -> Command[Literal["node_approve_accept", "node_approve_reject"]]:
+
+    approve_flag = interrupt({})
+
+    # 下面是中断恢复的代码
+
+    state_message_dict = state.get('lg_message_list')[-1]
+    update_message_dict = {
+      "id": state_message_dict.get('id'),
+      "status": "proceeded"
+    }
+    update_message_cls = await LgMessageService.item_update(session=session, row_dict=update_message_dict)
+    update_message_dict = update_message_cls.model_dump()
+
+    if approve_flag == 'Y':
+      return Command(
+        goto="node_approve_accept",
+        update={
+          "log_list": [f"node_wait_for_approve：主管审批通过"],
+          "lg_message_list": [update_message_dict],
+        }
+      )
+    else:
+      return Command(
+        goto="node_approve_reject",
+        update={
+          "log_list": [f"node_wait_for_approve：主管审批拒绝"],
+          "lg_message_list": [update_message_dict],
+        }
+      )
+
+  # 审批通过处理节点
+  async def node_approve_accept(state: StateSchema):
+    update_approve_dict = {
+      "id": state.get('approve').get('id'),
+      "status": "accept_approval",
+      "result_content": '审批通过......',
+    }
+    update_approve_cls = await LgApproveService.item_update(session=session, row_dict=update_approve_dict)
+    return {
+      "approve": update_approve_cls.model_dump(),
+      "log_list": [f"node_approve_accept：审批通过，等待财务打款"],
+    }
+
+  # 审批拒绝处理节点
+  async def node_approve_reject(state: StateSchema):
+    update_approve_dict = {
+      "id": state.get('approve').get('id'),
+      "status": "reject_approval",
+      "result_content": '审批拒绝......',
+    }
+    update_approve_cls = await LgApproveService.item_update(session=session, row_dict=update_approve_dict)
+    return {
+      "approve": update_approve_cls.model_dump(),
+      "log_list": [f"node_approve_accept：审批已经被拒绝"],
+    }
+
+  builder.add_node(node_create_approve)
+  builder.add_node(node_create_message)
+  builder.add_node(node_wait_for_approve)
+  builder.add_node(node_approve_accept)
+  builder.add_node(node_approve_reject)
+
+  builder.add_edge(START, 'node_create_approve')
+  builder.add_edge("node_create_approve", 'node_create_message')
+  builder.add_edge("node_create_message", 'node_wait_for_approve')
+
+  builder.add_edge('node_approve_accept', END)
+  builder.add_edge('node_approve_reject', END)
+
+  graph = builder.compile(checkpointer=checkpointer)
+
+  return graph