Files
cyclone/backend/tests/test_pubsub.py
T
Tyler 8bcb23c78d feat(api): parse endpoints pass EventBus into store writes
- api.parse_837 / parse_835: pass request.app.state.event_bus into store.add()
- conftest: autouse fixture wires a fresh EventBus onto app.state for every
  test, since TestClient does not invoke the FastAPI lifespan handler
  unless used as a context manager
- test_pubsub: split get_event_bus coverage into a raises-when-missing test
  and a returns-attached-bus test, both save/restore app.state.event_bus
  around the assertion so the autouse fixture's bus is preserved

Phase 2 complete: db init moved to lifespan, EventBus is the process-wide
publish point, and the two ingest endpoints publish claim_written /
remittance_written / activity_recorded events on every store.add().
2026-06-20 15:51:18 -06:00

135 lines
4.0 KiB
Python

"""Tests for the in-process EventBus.
These exercise the drop-oldest overflow strategy, per-kind fan-out, and
the non-blocking publish contract. They are async because the bus
exposes an async iterator for subscribers.
"""
from __future__ import annotations
import asyncio
import time
import pytest
from cyclone.pubsub import EventBus, get_event_bus
@pytest.mark.asyncio
async def test_publish_no_subscribers_is_noop():
bus = EventBus()
# No subscribers at all — must not raise.
await bus.publish("x", {"a": 1})
@pytest.mark.asyncio
async def test_publish_to_n_subscribers_delivers_to_all():
bus = EventBus()
queues = [bus.subscribe(["claim"]) for _ in range(3)]
await bus.publish("claim", {"id": "C1"})
received = [await asyncio.wait_for(q.__anext__(), timeout=0.5) for q in queues]
for event in received:
assert event == {"id": "C1", "_kind": "claim"}
@pytest.mark.asyncio
async def test_subscriber_only_receives_matching_kinds():
bus = EventBus()
queue = bus.subscribe(["a"])
await bus.publish("b", {"n": 1})
await bus.publish("a", {"n": 2})
event = await asyncio.wait_for(queue.__anext__(), timeout=0.5)
assert event == {"n": 2, "_kind": "a"}
@pytest.mark.asyncio
async def test_slow_subscriber_does_not_block_publish():
bus = EventBus(max_queue_size=2)
queue = bus.subscribe(["e"])
async def emit():
for i in range(3):
await bus.publish("e", {"i": i})
start = time.monotonic()
await emit()
elapsed = time.monotonic() - start
# Publishing must not block even though the subscriber queue is full
# after the second event; the drop-oldest policy keeps publishes non-blocking.
assert elapsed < 0.05, f"publish blocked for {elapsed:.3f}s"
# The slow subscriber retains only the last two events.
seen = []
for _ in range(2):
seen.append(await asyncio.wait_for(queue.__anext__(), timeout=0.5))
assert [e["i"] for e in seen] == [1, 2]
@pytest.mark.asyncio
async def test_queue_overflow_drops_oldest():
bus = EventBus(max_queue_size=2)
queue = bus.subscribe(["e"])
for i in range(3):
await bus.publish("e", {"i": i})
seen = []
for _ in range(2):
seen.append(await asyncio.wait_for(queue.__anext__(), timeout=0.5))
assert [e["i"] for e in seen] == [1, 2]
@pytest.mark.asyncio
async def test_multiple_concurrent_subscribers_each_get_all_events():
bus = EventBus()
queues = [bus.subscribe(["claim"]) for _ in range(2)]
for i in range(5):
await bus.publish("claim", {"i": i})
for q in queues:
seen = []
for _ in range(5):
seen.append(await asyncio.wait_for(q.__anext__(), timeout=0.5))
assert [e["i"] for e in seen] == [0, 1, 2, 3, 4]
def test_get_event_bus_raises_when_app_state_uninitialized():
"""get_event_bus() late-imports cyclone.api; if the lifespan handler
hasn't set ``app.state.event_bus`` (or it's been cleared), the
AttributeError must surface so callers can fail loudly."""
from cyclone.api import app
# The autouse conftest fixture sets app.state.event_bus for every test
# so that endpoint code can call request.app.state.event_bus. We pop
# the key entirely here so __getattr__ raises AttributeError rather
# than returning None for an explicitly-None slot.
state_dict = app.state._state
saved = state_dict.pop("event_bus", None)
try:
with pytest.raises((AttributeError, RuntimeError)):
get_event_bus()
finally:
if saved is not None:
state_dict["event_bus"] = saved
def test_get_event_bus_returns_app_state_bus():
"""When the lifespan handler has initialised the bus, get_event_bus()
returns it. Validates the happy path under the same late-import."""
from cyclone.api import app
from cyclone.pubsub import EventBus
saved = getattr(app.state, "event_bus", None)
bus = EventBus()
app.state.event_bus = bus
try:
assert get_event_bus() is bus
finally:
app.state.event_bus = saved