Langgraph HITL 中断运行，用户输入后输出打字效果

锋行天下2026-10-30 19:33
ini 复制代码
from langchain_core.messages import AIMessageChunk, HumanMessage
from langgraph.types import Command,interrupt
from langgraph.graph import StateGraph, START, END, MessagesState
from langgraph.checkpoint.memory import InMemorySaver  # ✅ 补上导入
from dotenv import load_dotenv
load_dotenv(override=True)
from langchain.chat_models import init_chat_model

model = init_chat_model(
    model="deepseek-chat",
    extra_body={
        "thinking": {
            "type": "disabled"
        }
    }
)

class OverAllState(MessagesState):
    text: str

def input_node(state: OverAllState) -> OverAllState:
    val = interrupt("请输入")
    res = model.invoke([HumanMessage(val)])
    return {
        "messages": [res]
    }

builder = StateGraph(state_schema=OverAllState)
builder.add_node("input_node", input_node)
builder.add_edge(START, "input_node")
builder.add_edge("input_node", END)
checkpointer = InMemorySaver()
graph = builder.compile(checkpointer=checkpointer)

config = {
    "configurable": {"thread_id": "9667"}
}
graph.invoke({},config=config)
val=input("请输入")
# 流式输出，把内容里的换行替换成空格，实现"打字机不自动换行"
for chunk, metadata in graph.stream(
    Command(resume=val),
    config=config,
    stream_mode="messages",
):
    if isinstance(chunk, AIMessageChunk) and chunk.content:
        print(chunk.content, end="", flush=True)