deer-flow/backend/tests/test_extension_task_lifecycle.py
Nan Gao 7389331e65
feat(extensions): observe task lifecycle and system model calls (#4684)
* feat(extensions): observe task lifecycle and system model calls

PR 1 (#4636) gave extensions a middleware chain, and a middleware only sees
what passes through the agent graph. Two runtime surfaces stay invisible to
it: when a lead run or a subagent begins and ends, and the DeerFlow-owned
model calls made outside the graph. This slice adds both, with no new
Gateway surface -- routers, services, and the reference extension stay in
PR 3.

Contract (deerflow-extension-api 0.1.1)
---------------------------------------
Two contribution kinds join `middlewares` on the registry:
`task_lifecycle` (`on_task_start` / `on_task_stop`, receiving a `TaskInfo`
and a conservative `TaskOutcome` of completed / aborted / failed) and
`system_model_observer` (`on_system_model_call`, receiving a
`SystemOperationKind`, a `SystemModelRequest` snapshot, and a
`SystemModelResult` carrying either the response or the provider exception
plus a duration).

`SystemModelRequest.messages` normalizes to a tuple at construction. Goal
evaluation and memory extraction pass a message list while title generation
and summarization pass one prompt string, and a bare `str` already satisfies
`Sequence` -- without normalization an observer iterating `request.messages`
would silently walk characters. Copying also makes the frozen snapshot
immutable in fact rather than only by declaration, since observations may run
after the call site returns and keeps mutating its own list.

Registry marks and rollbacks become per-bucket and positional, so an
`install()` that fails after registering two different kinds cannot leave one
of them behind. `needs_task_store` now covers all three kinds: a deployment
that registers only lifecycle hooks still gets a task store.

Task lifecycle
--------------
The lead worker notifies start after the run has started and stop after
completion persistence and the completion hook, but before clearing the
finalizing barrier and publishing the stream end -- holding the barrier
across stop is what keeps a same-thread replacement run from overlapping this
task's lifecycle. Cancellation raised out of the stop notification is
deferred, not propagated in place, so a cancelled run still clears the
barrier and emits its end frame. A subagent with a parent `run_id` wraps its
execution in the same pair inside `finally`, reporting `parent_task_id` so a
delegation tree is reconstructable; a subagent without a `run_id` (embedded
client, standalone LangGraph Server) logs and skips rather than inventing a
parent. Contributors run in registration order inside one shared 3s budget
and every failure is logged and failed open.

System model calls
------------------
Four kinds cover the model calls the middleware chain cannot see: goal
evaluation, memory extraction, title generation, and summarization. Each site
reports both terminal paths without changing the provider exception the host
observes, short-circuits on `has_system_model_observers`, and passes the live
task store when the runtime has one (detached work gets an isolated store).
The sync summarization half stays unobserved on purpose -- it and its only
host caller are the sync side of an async-only runtime, so notifying there
would block a thread on a call site the host never reaches; the reason is
recorded at the call site.

The DeerMem backend must stay vendorable and cannot import the extension API,
so it reports through a new `MemoryCallbacks.on_memory_llm_result` host hook
that the DeerFlow-side callbacks translate into an observation.

Notification loop
-----------------
Extension resources must be touched on the loop that created them, but
subagents can execute on isolated loops and DeerMem runs on a worker thread.
The Gateway registers its serving loop before any runtime dependency starts
and resets it last through the exit stack, so every startup-failure and
cancellation path is covered. Awaited hooks raised on another loop are
dispatched across with `run_coroutine_threadsafe` and awaited under the same
budget; synchronous sites submit fire-and-forget work. Shutdown stops
accepting detached observations before the memory flush -- that flush runs on
a worker thread and can emit memory observations -- while keeping the loop
alive for awaited task hooks until run and subagent drain completes.

Tests
-----
`test_extension_task_lifecycle.py`, `test_extension_subagent_lifecycle.py`,
and `test_extension_system_model_calls.py` cover ordering, fail-open, budget
exhaustion, snapshot binding under a concurrent singleton replacement, the
loop-dispatch and shutdown-suspension paths, and both terminal paths at every
call site. `test_gateway_run_drain_shutdown.py` pins the stop-before-barrier
and drain ordering.

* fix(extensions): decide notification fail-open by origin, observe cancellation

`_notify_each` only guarded `Exception`, so a contributor letting a
`CancelledError` escape — an extension implementing an internal timeout with
cancellation, say — skipped its successors and reached the worker's
deferred-interrupt path, ending an otherwise successful run as cancelled.
Fail-open is about where a failure came from, not its base class: only a
genuine cancellation of the host task increments `Task.cancelling()`, so
propagate on that and contain everything else. `KeyboardInterrupt` /
`SystemExit` still propagate.

`observe_system_model_call` skipped observers on cancellation for the same
base-class reason, leaving goal / title / summarization silent on a terminal
path that is routine — interrupt/rollback admission and shutdown both cancel
the run task, with the provider tokens already spent. Awaiting observers there
is unreliable (a repeated cancel interrupts that await before any of them
runs), so report through the same non-blocking submission the synchronous
memory bridge uses, then propagate the cancellation untouched.

DeerMem keeps `BaseException` around its provider call, now with the reason
recorded: that path runs on a worker thread, where cancelling the awaiting
side never interrupts the running thread, so `CancelledError` cannot arrive
at all. Its host-hook wrapper narrows to `Exception` — only the hook's own
failures are non-fatal, and an observability path must not swallow a process
teardown signal.

* fix(extensions): warn on budget exhaustion, scope observer logs by task, propagate teardown

Review response on #4684:

- The memory observation bridge caught BaseException, which would swallow
  a teardown signal raised while dispatching; it now catches Exception,
  matching the boundary the DeerMem-side call site documents and tests.
- A notification-budget timeout raised mid-hook fell into the generic
  hook-failure path and logged an asyncio-internal traceback; it now logs
  a warning like the pre-hook budget skip, while a TimeoutError a
  contributor raises on its own stays classified as a hook failure.
- System model observer logs passed the operation kind as the task id,
  so log lines said "task goal/title/..."; they now carry the task
  scope id alongside the kind.
2026-08-11 16:33:22 +08:00

439 lines
14 KiB
Python

"""Task lifecycle extension notifications and outcome classification."""
from __future__ import annotations
import asyncio
import logging
from types import SimpleNamespace
from unittest.mock import AsyncMock
import pytest
from deerflow_extension_api import (
EXTENSION_TASK_STORE_KEY,
ExtensionData,
TaskInfo,
TaskOutcome,
)
from langgraph.checkpoint.memory import InMemorySaver
from deerflow.extensions.notify import (
lead_task_id,
lead_task_outcome,
notify_task_start,
notify_task_stop,
subagent_task_outcome,
)
from deerflow.extensions.registry import ExtensionRegistry
from deerflow.runtime.runs.manager import RunManager
from deerflow.runtime.runs.schemas import RunStatus
from deerflow.runtime.runs.worker import RunContext, run_agent
class _Recorder:
def __init__(self) -> None:
self.events: list[tuple[str, str, str]] = []
async def on_task_start(self, app_store, task_store, info):
self.events.append(("start", info.task_id, info.kind))
async def on_task_stop(self, app_store, task_store, info, outcome):
self.events.append(("stop", info.task_id, outcome.value))
def _extensions(*contributors):
registry = ExtensionRegistry()
for index, contributor in enumerate(contributors):
with registry.attributed_to(f"ext{index}:install"):
registry.task_lifecycle(contributor)
return registry.build()
def _info(task_id: str = "task-1", kind: str = "lead") -> TaskInfo:
return TaskInfo(task_id=task_id, run_id="run-1", thread_id="thread-1", kind=kind)
def test_task_identity_and_outcome_classification_are_explicit():
assert lead_task_id("run-abc") == "run-abc"
assert lead_task_outcome(aborted=True, succeeded=True) is TaskOutcome.ABORTED
assert lead_task_outcome(aborted=False, succeeded=True) is TaskOutcome.COMPLETED
assert lead_task_outcome(aborted=False, succeeded=False) is TaskOutcome.FAILED
assert subagent_task_outcome(cancelled=True, succeeded=True) is TaskOutcome.ABORTED
assert subagent_task_outcome(cancelled=False, succeeded=True) is TaskOutcome.COMPLETED
assert subagent_task_outcome(cancelled=False, succeeded=False) is TaskOutcome.FAILED
@pytest.mark.asyncio
async def test_start_and_stop_reach_contributors_in_order():
first = _Recorder()
second = _Recorder()
extensions = _extensions(first, second)
store = ExtensionData("task-1")
await notify_task_start(extensions, store, _info())
await notify_task_stop(extensions, store, _info(), TaskOutcome.COMPLETED)
assert first.events == [("start", "task-1", "lead"), ("stop", "task-1", "completed")]
assert second.events == first.events
@pytest.mark.asyncio
async def test_one_malformed_or_failing_contributor_does_not_stop_the_rest():
class _WrongShape:
def on_task_start(self, app_store, task_store, info):
raise RuntimeError("sync boom")
survivor = _Recorder()
await notify_task_start(
_extensions(_WrongShape(), survivor),
ExtensionData("task-1"),
_info(),
)
assert survivor.events == [("start", "task-1", "lead")]
@pytest.mark.asyncio
async def test_notification_timeout_is_one_shared_budget():
reached: list[str] = []
class _Hang:
async def on_task_stop(self, app_store, task_store, info, outcome):
reached.append("hang")
await asyncio.sleep(10)
class _Starved:
async def on_task_stop(self, app_store, task_store, info, outcome):
reached.append("starved")
loop = asyncio.get_running_loop()
started = loop.time()
await notify_task_stop(
_extensions(_Hang(), _Starved()),
ExtensionData("task-1"),
_info(),
TaskOutcome.COMPLETED,
timeout=0.02,
)
assert reached == ["hang"]
assert loop.time() - started < 1
@pytest.mark.asyncio
async def test_budget_exhaustion_mid_hook_logs_a_warning_not_a_traceback(caplog):
# Spending the shared budget mid-hook is the same expected operational
# condition as the pre-hook skip, not a hook failure.
class _Hang:
async def on_task_stop(self, app_store, task_store, info, outcome):
await asyncio.sleep(10)
with caplog.at_level(logging.WARNING, logger="deerflow.extensions.notify"):
await notify_task_stop(
_extensions(_Hang()),
ExtensionData("task-1"),
_info(),
TaskOutcome.COMPLETED,
timeout=0.02,
)
records = [record for record in caplog.records if record.name == "deerflow.extensions.notify"]
assert [record.levelno for record in records] == [logging.WARNING]
assert "timed out" in records[0].getMessage()
assert "task-1" in records[0].getMessage()
assert records[0].exc_info is None
@pytest.mark.asyncio
async def test_contributor_timeout_error_before_budget_is_a_hook_failure(caplog):
# A TimeoutError the contributor raises on its own is not budget
# exhaustion; it stays classified as a hook failure.
class _TimedOut:
async def on_task_stop(self, app_store, task_store, info, outcome):
raise TimeoutError("the contributor's own downstream call timed out")
with caplog.at_level(logging.WARNING, logger="deerflow.extensions.notify"):
await notify_task_stop(
_extensions(_TimedOut()),
ExtensionData("task-1"),
_info(),
TaskOutcome.COMPLETED,
timeout=30,
)
# And with no notification budget at all.
await notify_task_stop(
_extensions(_TimedOut()),
ExtensionData("task-1"),
_info(),
TaskOutcome.COMPLETED,
)
records = [record for record in caplog.records if record.name == "deerflow.extensions.notify"]
assert [record.levelno for record in records] == [logging.ERROR, logging.ERROR]
assert all("failed" in record.getMessage() for record in records)
class _RunRecorder(_Recorder):
def __init__(self) -> None:
super().__init__()
self.start_infos: list[TaskInfo] = []
self.start_stores: list[ExtensionData] = []
async def on_task_start(self, app_store, task_store, info):
self.start_infos.append(info)
self.start_stores.append(task_store)
await super().on_task_start(app_store, task_store, info)
class _OkAgent:
def __init__(self) -> None:
self.runtime_context = None
async def astream(self, graph_input, config=None, stream_mode=None, subgraphs=False):
self.runtime_context = (config or {}).get("context")
yield {"messages": []}
class _BoomAgent:
async def astream(self, graph_input, config=None, stream_mode=None, subgraphs=False):
raise RuntimeError("agent exploded")
yield # pragma: no cover
def _bridge():
return SimpleNamespace(
publish=AsyncMock(),
publish_end=AsyncMock(),
cleanup=AsyncMock(),
)
@pytest.mark.asyncio
async def test_run_agent_uses_the_run_bound_snapshot_for_lifecycle_and_task_store():
recorder = _RunRecorder()
extensions = _extensions(recorder)
manager = RunManager()
record = await manager.create("thread-ext", assistant_id="custom-agent")
agent = _OkAgent()
await run_agent(
_bridge(),
manager,
record,
ctx=RunContext(checkpointer=InMemorySaver(), extensions=extensions),
agent_factory=lambda *, config: agent,
graph_input={},
config={},
)
assert record.status is RunStatus.success
assert recorder.events == [
("start", record.run_id, "lead"),
("stop", record.run_id, "completed"),
]
assert recorder.start_infos[0].agent_name == "custom-agent"
assert agent.runtime_context[EXTENSION_TASK_STORE_KEY] is recorder.start_stores[0]
@pytest.mark.asyncio
async def test_run_agent_reports_failed_and_skips_runs_that_never_started():
recorder = _RunRecorder()
extensions = _extensions(recorder)
manager = RunManager()
failed = await manager.create("thread-failed")
await run_agent(
_bridge(),
manager,
failed,
ctx=RunContext(checkpointer=InMemorySaver(), extensions=extensions),
agent_factory=lambda *, config: _BoomAgent(),
graph_input={},
config={},
)
assert failed.status is RunStatus.error
assert recorder.events[-1] == ("stop", failed.run_id, "failed")
skipped = await manager.create("thread-skipped")
await manager.cancel(skipped.run_id)
before = list(recorder.events)
await run_agent(
_bridge(),
manager,
skipped,
ctx=RunContext(checkpointer=InMemorySaver(), extensions=extensions),
agent_factory=lambda *, config: _OkAgent(),
graph_input={},
config={},
)
assert recorder.events == before
@pytest.mark.asyncio
async def test_lead_stop_runs_after_completion_hook_and_before_stream_end():
events: list[str] = []
manager = RunManager()
record = await manager.create("thread-order")
bridge = _bridge()
bridge.publish_end.side_effect = lambda run_id: events.append("stream-end")
class _OrderingRecorder(_RunRecorder):
async def on_task_stop(self, app_store, task_store, info, outcome):
assert record.finalizing is True
assert bridge.publish_end.await_count == 0
events.append("task-stop")
await super().on_task_stop(
app_store,
task_store,
info,
outcome,
)
async def _on_completed(_record):
events.append("run-completed")
class _CancelledAgent:
async def astream(
self,
graph_input,
config=None,
stream_mode=None,
subgraphs=False,
):
raise asyncio.CancelledError()
yield # pragma: no cover
await run_agent(
bridge,
manager,
record,
ctx=RunContext(
checkpointer=InMemorySaver(),
extensions=_extensions(_OrderingRecorder()),
on_run_completed=_on_completed,
),
agent_factory=lambda *, config: _CancelledAgent(),
graph_input={},
config={},
)
assert events == ["run-completed", "task-stop", "stream-end"]
assert record.finalizing is False
@pytest.mark.asyncio
async def test_lead_stop_interrupt_is_deferred_until_final_cleanup():
class _StopInterrupt(BaseException):
pass
class _InterruptingRecorder(_RunRecorder):
async def on_task_stop(self, app_store, task_store, info, outcome):
await super().on_task_stop(
app_store,
task_store,
info,
outcome,
)
raise _StopInterrupt("shutdown")
manager = RunManager()
record = await manager.create("thread-interrupt")
bridge = _bridge()
with pytest.raises(_StopInterrupt, match="shutdown"):
await run_agent(
bridge,
manager,
record,
ctx=RunContext(
checkpointer=InMemorySaver(),
extensions=_extensions(_InterruptingRecorder()),
),
agent_factory=lambda *, config: _OkAgent(),
graph_input={},
config={},
)
assert record.finalizing is False
bridge.publish_end.assert_awaited_once_with(record.run_id)
@pytest.mark.asyncio
async def test_contributor_raising_cancellederror_cannot_interrupt_run_cleanup():
# Fail-open is decided by origin, not base class: a contributor that lets a
# CancelledError escape must not skip its successors, and must not reach the
# worker's deferred-interrupt path, which would end an otherwise successful
# run as cancelled.
class _Rogue:
async def on_task_stop(self, app_store, task_store, info, outcome):
raise asyncio.CancelledError()
survivor = _RunRecorder()
manager = RunManager()
record = await manager.create("thread-rogue-stop")
bridge = _bridge()
await run_agent(
bridge,
manager,
record,
ctx=RunContext(
checkpointer=InMemorySaver(),
extensions=_extensions(_Rogue(), survivor),
),
agent_factory=lambda *, config: _OkAgent(),
graph_input={},
config={},
)
assert record.status is RunStatus.success
assert survivor.events[-1] == ("stop", record.run_id, "completed")
assert record.finalizing is False
bridge.publish_end.assert_awaited_once_with(record.run_id)
@pytest.mark.asyncio
async def test_lead_stop_cancellation_is_deferred_rather_than_swallowed():
# CancelledError derives from BaseException, so the non-fatal `except
# Exception` guard around the stop notification must not absorb it. The
# stimulus has to be a genuine cancellation of the run task — a contributor
# raising CancelledError is contained as an extension failure instead.
entered = asyncio.Event()
class _SlowRecorder(_RunRecorder):
async def on_task_stop(self, app_store, task_store, info, outcome):
await super().on_task_stop(
app_store,
task_store,
info,
outcome,
)
entered.set()
await asyncio.sleep(10)
manager = RunManager()
record = await manager.create("thread-cancel-stop")
bridge = _bridge()
task = asyncio.create_task(
run_agent(
bridge,
manager,
record,
ctx=RunContext(
checkpointer=InMemorySaver(),
extensions=_extensions(_SlowRecorder()),
),
agent_factory=lambda *, config: _OkAgent(),
graph_input={},
config={},
)
)
await entered.wait()
task.cancel()
with pytest.raises(asyncio.CancelledError):
await task
assert record.finalizing is False
bridge.publish_end.assert_awaited_once_with(record.run_id)