Run plugin asgi_wrapper middleware inside the startup-arming layer

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
This commit is contained in:
Alex Garcia 2026-07-30 18:28:59 -07:00
commit 3125c36802
3 changed files with 186 additions and 2 deletions

View file

@ -7,6 +7,13 @@ These exercise Datasette._startup_sequence() via three different callers:
- AsgiRunOnFirstRequest, the fallback for hosts that never send lifespan
events (this is what DatasetteClient / plain httpx2.ASGITransport uses)
- Both at once, to prove startup hooks run at most once
Also covers ticket 05 (plans/first-request/04-core-plan.md decision #7):
plugin asgi_wrapper middleware runs INSIDE AsgiRunOnFirstRequest (below it)
but OUTSIDE AsgiLifespan (above it), so wrappers only ever see http/
websocket scopes after startup has completed, in both the lifespan and
fallback paths - while lifespan scopes still flow through wrappers
unchanged.
"""
import asyncio
@ -257,3 +264,145 @@ async def test_setup_db_still_runs_when_invoke_startup_ran_first(tmp_path, monke
# Idempotency: a second call must not recompute.
await ds._startup_sequence()
assert call_count["n"] == 1
@pytest.mark.asyncio
async def test_asgi_wrapper_runs_after_startup_fallback_path():
# Ticket 05: plugin asgi_wrapper middleware must never see an http scope
# before startup has completed - even on the fallback path (no ASGI
# lifespan events at all), which is what plain httpx2.ASGITransport /
# bare app() embedding exercises. Before the app() reorder in this
# ticket, the wrapper loop ran OUTSIDE (above) AsgiRunOnFirstRequest, so
# this assertion could see _startup_invoked is False on request #1 -
# this test fails on the pre-reorder app().
class AssertStartupPlugin:
__name__ = "AssertStartupPlugin"
@hookimpl
def asgi_wrapper(self, datasette):
def wrap(app):
async def check_startup(scope, receive, send):
if scope["type"] == "http":
assert datasette._startup_invoked is True, (
"asgi_wrapper saw an http scope before startup "
"completed"
)
await app(scope, receive, send)
return check_startup
return wrap
ds = Datasette(memory=True)
pm.register(AssertStartupPlugin(), name="assert_startup_plugin")
try:
assert ds._startup_invoked is False
app = ds.app()
transport = httpx2.ASGITransport(app=app)
async with httpx2.AsyncClient(
transport=transport, base_url="http://localhost"
) as client:
response = await client.get("/-/versions.json")
assert response.status_code == 200
finally:
pm.unregister(name="assert_startup_plugin")
assert ds._startup_invoked is True
@pytest.mark.asyncio
async def test_short_circuit_wrapper_no_longer_defers_startup():
# Ticket 05: a wrapper that short-circuits (returns a response without
# ever calling the inner app - the shape of a 401/403/CORS-preflight
# responder) used to mean startup never ran for that request, because
# the wrapper sat OUTSIDE AsgiRunOnFirstRequest. Now that
# AsgiRunOnFirstRequest is outermost, it arms startup before the
# wrapper (or anything else) ever sees the scope.
class ShortCircuitPlugin:
__name__ = "ShortCircuitPlugin"
@hookimpl
def asgi_wrapper(self, datasette):
def wrap(app):
async def forbidden(scope, receive, send):
if scope["type"] != "http":
await app(scope, receive, send)
return
await send(
{
"type": "http.response.start",
"status": 403,
"headers": [[b"content-type", b"text/plain"]],
}
)
await send(
{
"type": "http.response.body",
"body": b"Forbidden",
}
)
# Deliberately never call app(...): this is the
# short-circuiting shape (auth-passwords, auth-tailscale,
# datasette-cors preflight).
return forbidden
return wrap
ds = Datasette(memory=True)
pm.register(ShortCircuitPlugin(), name="short_circuit_plugin")
try:
assert ds._startup_invoked is False
app = ds.app()
transport = httpx2.ASGITransport(app=app)
async with httpx2.AsyncClient(
transport=transport, base_url="http://localhost"
) as client:
response = await client.get("/-/versions.json")
assert response.status_code == 403
finally:
pm.unregister(name="short_circuit_plugin")
assert ds._startup_invoked is True
@pytest.mark.asyncio
async def test_asgi_wrapper_still_sees_lifespan_scopes():
# Ticket 05: the reorder only moves AsgiRunOnFirstRequest outside the
# wrapper loop - AsgiLifespan stays inside it, so a wrapper that
# inspects/wraps lifespan scopes still sees identical message flow.
# Pin that lifespan scopes keep reaching wrappers alongside http scopes.
seen_types = []
class RecordingPlugin:
__name__ = "RecordingPlugin"
@hookimpl
def asgi_wrapper(self, datasette):
def wrap(app):
async def record(scope, receive, send):
seen_types.append(scope["type"])
await app(scope, receive, send)
return record
return wrap
ds = Datasette(memory=True)
pm.register(RecordingPlugin(), name="recording_plugin")
try:
app = ds.app()
messages = await _drive_lifespan_startup(app)
assert {"type": "lifespan.startup.complete"} in messages
transport = httpx2.ASGITransport(app=app)
async with httpx2.AsyncClient(
transport=transport, base_url="http://localhost"
) as client:
response = await client.get("/-/versions.json")
assert response.status_code == 200
finally:
pm.unregister(name="recording_plugin")
assert "lifespan" in seen_types
assert "http" in seen_types