add main.py

main.py

@@ -0,0 +1,92 @@
+"""Human-in-the-loop: кастомное прерывание (interrupt / resume) в LangGraph."""
+from __future__ import annotations
+
+from typing import TypedDict
+
+import questionary
+from langgraph.checkpoint.memory import InMemorySaver
+from langgraph.constants import START
+from langgraph.graph import StateGraph
+from langgraph.types import Command, interrupt
+
+
+class GraphState(TypedDict):
+    """Состояние графа: начальные данные и ответ пользователя."""
+
+    foo: str
+    human_value: str
+
+
+def human_node(state: GraphState) -> GraphState:
+    """Узел с кастомным прерыванием — ждёт ответ пользователя."""
+    payload = interrupt(
+        {
+            "type": "alert",
+            "question": "Уверены что хотите продолжить?",
+            "allow_responds": ["approve", "reject"],
+        }
+    )
+
+    answer = payload.get("answer", "")
+    print(f"!!! {payload.get('type', 'alert')} !!!")
+    print(f"> Received an input from the interrupt: {answer}")
+
+    return {
+        "foo": state.get("foo", ""),
+        "human_value": answer,
+    }
+
+
+def _ask_user(payload: dict) -> dict:
+    """Показать вопрос и записать ответ в payload."""
+    print(payload)
+    options = payload.get("allow_responds") or ["approve", "reject"]
+    question = payload.get("question", "Выберите вариант:")
+    choice = questionary.select(question, choices=options).ask()
+    if choice is None:
+        choice = options[0]
+    updated = dict(payload)
+    updated["answer"] = choice
+    return updated
+
+
+def run_graph() -> GraphState:
+    """Запуск графа с обработкой прерывания и возобновлением."""
+    builder = StateGraph(GraphState)
+    builder.add_node("human_node", human_node)
+    builder.add_edge(START, "human_node")
+
+    graph = builder.compile(checkpointer=InMemorySaver())
+    config = {"configurable": {"thread_id": "hitl-interrupt-demo"}}
+    initial: GraphState = {"foo": "initialized", "human_value": ""}
+
+    final_state: GraphState = initial
+
+    stream = graph.stream(initial, config)
+    for chunk in stream:
+        if "__interrupt__" in chunk:
+            print("Произошла остановка")
+            interrupt_tuple = chunk["__interrupt__"]
+            payload = dict(interrupt_tuple[0].value)
+            resumed_payload = _ask_user(payload)
+
+            resume_stream = graph.stream(Command(resume=resumed_payload), config)
+            for resume_chunk in resume_stream:
+                if "human_node" in resume_chunk:
+                    final_state = resume_chunk["human_node"]
+                    print({"node": resume_chunk})
+        elif "human_node" in chunk:
+            final_state = chunk["human_node"]
+            print(chunk)
+
+    return final_state
+
+
+def main() -> None:
+    result = run_graph()
+    print("\n=== Итоговое состояние ===")
+    print(result)
+
+
+if __name__ == "__main__":
+    main()