hermes-agent/tests/agent/test_stream_read_timeout_floor.py
xxxigm 615ad97928
fix(streaming): stop socket read timeout from preempting stale-stream detector (#43570)
* fix(streaming): stop socket read timeout from preempting stale-stream detector

The stale-stream detector is deliberately scaled to 180-300s so reasoning
models (e.g. Opus) can pause mid-stream during extended thinking. But the
httpx socket read timeout stayed at a flat 120s for cloud providers and fired
first, tearing down healthy reasoning streams before the detector (which owns
retry + diagnostics) could act. Symptom: every Copilot/Opus turn dies with
ReadTimeout at a consistent ~125s and never completes.

Floor the cloud socket read timeout at the stale-stream timeout so it can no
longer fire before the detector. Local providers and explicit
HERMES_STREAM_READ_TIMEOUT / request_timeout_seconds overrides are unchanged.

* test(streaming): pin read-timeout >= stale-stream invariant for cloud reasoning streams

Cover the contract that the httpx socket read timeout is never shorter than
the stale-stream detector for cloud providers on the default: small contexts
floor to 180s, >=50K to 240s, >=100K to 300s; explicit overrides win; local
providers and the unresolved-value fallback are unaffected.
2026-06-10 20:21:38 -05:00

111 lines
4.7 KiB
Python

"""Stream read timeout must never preempt the stale-stream detector.
Reasoning models (e.g. Opus) routinely pause mid-stream for minutes during
extended thinking. The stale-stream detector is deliberately scaled up to
tolerate this (180s base, raised to 240s/300s for large contexts). The httpx
socket read timeout, however, defaulted to a flat 120s for cloud providers and
fired *first* — tearing down a healthy reasoning stream before the stale
detector (which owns retry + diagnostics) could act.
These tests pin the invariant: for a cloud provider on the default read
timeout, the httpx socket read timeout is floored at the stale-stream timeout
so it can never fire before the detector. They mirror the inline logic in
``agent/chat_completion_helpers.py`` (the real builder lives deep inside a
worker thread, so — like ``test_local_stream_timeout.py`` — the resolution is
reproduced here rather than driven end-to-end).
"""
import os
import pytest
from agent.model_metadata import is_local_endpoint
def _resolve_stale_timeout(base_url, est_tokens, stale_base=180.0):
"""Mirror of the stale-stream detector resolution."""
if stale_base == 180.0 and base_url and is_local_endpoint(base_url):
return float("inf") # detector disabled for local providers
if est_tokens > 100_000:
return max(stale_base, 300.0)
if est_tokens > 50_000:
return max(stale_base, 240.0)
return stale_base
def _resolve_read_timeout(base_url, stale_timeout, base_timeout=1800.0):
"""Mirror of the httpx socket read-timeout builder (cloud branch)."""
read_timeout = float(os.getenv("HERMES_STREAM_READ_TIMEOUT", 120.0))
if read_timeout == 120.0 and base_url and is_local_endpoint(base_url):
read_timeout = base_timeout
elif (
read_timeout == 120.0
and stale_timeout is not None
and stale_timeout != float("inf")
and stale_timeout > read_timeout
):
read_timeout = stale_timeout
return read_timeout
CLOUD_URLS = [
"https://api.githubcopilot.com",
"https://api.openai.com",
"https://openrouter.ai/api",
"https://api.anthropic.com",
]
class TestCloudReadTimeoutFloor:
@pytest.fixture(autouse=True)
def _clear_env(self):
with pytest.MonkeyPatch.context() as mp:
mp.delenv("HERMES_STREAM_READ_TIMEOUT", raising=False)
yield
@pytest.mark.parametrize("base_url", CLOUD_URLS)
@pytest.mark.parametrize("est_tokens", [0, 10_000, 60_000, 150_000])
def test_read_timeout_never_below_stale(self, base_url, est_tokens):
"""Core invariant: the socket read timeout >= the stale detector."""
stale = _resolve_stale_timeout(base_url, est_tokens)
read = _resolve_read_timeout(base_url, stale)
assert read >= stale
@pytest.mark.parametrize("base_url", CLOUD_URLS)
def test_small_context_floored_to_stale_base(self, base_url):
"""Reported case: ~120s timeouts on Copilot are raised to the 180s base."""
stale = _resolve_stale_timeout(base_url, est_tokens=37_000)
read = _resolve_read_timeout(base_url, stale)
assert read == 180.0
@pytest.mark.parametrize("base_url", CLOUD_URLS)
def test_large_context_tracks_scaled_stale(self, base_url):
"""Big contexts scale the stale detector; the read timeout follows."""
assert _resolve_read_timeout(base_url, _resolve_stale_timeout(base_url, 60_000)) == 240.0
assert _resolve_read_timeout(base_url, _resolve_stale_timeout(base_url, 150_000)) == 300.0
def test_user_override_is_respected(self):
"""An explicit HERMES_STREAM_READ_TIMEOUT is never overridden by the floor."""
with pytest.MonkeyPatch.context() as mp:
mp.setenv("HERMES_STREAM_READ_TIMEOUT", "90")
stale = _resolve_stale_timeout("https://api.githubcopilot.com", est_tokens=0)
assert _resolve_read_timeout("https://api.githubcopilot.com", stale) == 90.0
class TestLocalUnaffected:
@pytest.fixture(autouse=True)
def _clear_env(self):
with pytest.MonkeyPatch.context() as mp:
mp.delenv("HERMES_STREAM_READ_TIMEOUT", raising=False)
yield
def test_local_still_raised_to_base(self):
"""Local providers keep their existing behavior (raise to base timeout)."""
stale = _resolve_stale_timeout("http://localhost:11434", est_tokens=0)
assert stale == float("inf") # detector disabled for local
read = _resolve_read_timeout("http://localhost:11434", stale)
assert read == 1800.0 # not clamped by inf
def test_stale_none_falls_back_to_default(self):
"""If the stale value is unresolved, the read timeout keeps its default."""
assert _resolve_read_timeout("https://api.githubcopilot.com", None) == 120.0