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Because we were propagating the task ID config key, the stream mode was always overridden as "values", meaning the token, etc. callback handlers were never added within the remote graphs. --------- Signed-off-by: William Fu-Hinthorn <13333726+hinthornw@users.noreply.github.com>
90 lines
2.4 KiB
Python
90 lines
2.4 KiB
Python
from typing import Annotated
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from langchain_core.messages import AIMessage, BaseMessage, ToolMessage
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from langchain_core.tools import tool
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from typing_extensions import TypedDict
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from langgraph.func import entrypoint, task
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from langgraph.graph.message import add_messages
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from tests.fake_chat import FakeChatModel
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class AgentState(TypedDict):
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messages: Annotated[list[BaseMessage], add_messages]
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@tool
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def search_api(query: str) -> str:
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"""Searches the API for the query."""
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return f"result for {query}"
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tools = [search_api]
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tools_by_name = {t.name: t for t in tools}
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def get_model():
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model = FakeChatModel(
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messages=[
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AIMessage(
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id="ai1",
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content="",
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tool_calls=[
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{
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"id": "tool_call123",
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"name": "search_api",
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"args": {"query": "query"},
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},
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],
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),
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AIMessage(
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id="ai2",
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content="",
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tool_calls=[
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{
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"id": "tool_call234",
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"name": "search_api",
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"args": {"query": "another", "idx": 0},
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},
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{
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"id": "tool_call567",
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"name": "search_api",
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"args": {"query": "a third one", "idx": 1},
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},
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],
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),
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AIMessage(id="ai3", content="answer"),
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]
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)
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return model
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@task
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def foo():
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return "foo"
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@entrypoint()
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async def app(state: AgentState) -> AgentState:
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model = get_model()
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max_steps = 100
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messages = state["messages"][:]
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await foo() # Very useful call here ya know.
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for _ in range(max_steps):
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message = await model.ainvoke(messages)
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messages.append(message)
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if not message.tool_calls:
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break
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# Assume it's the search tool
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tool_results = await search_api.abatch(
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[t["args"]["query"] for t in message.tool_calls]
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)
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messages.extend(
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[
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ToolMessage(content=tool_res, tool_call_id=tc["id"])
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for tc, tool_res in zip(message.tool_calls, tool_results)
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]
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)
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return entrypoint.final(value=messages[-1], save={"messages": messages})
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