Root cause, confirmed live against Postgres and reproduced end-to-end
through two real WebSocket connections: ws/chat.py shares one AsyncSession
for a whole connection's lifetime. A read-only action (e.g. a "join"
frame's membership check) can leave a transaction open with nothing to
commit it until the next write. Postgres's now()/CURRENT_TIMESTAMP
returns that transaction's *start* time in that case, not the actual
statement's -- so a reply sent after any idle/reading period got
timestamped to when the idle period started, sorting it before messages
that were genuinely sent earlier. This is independent of the two earlier
#45 fixes (missing ORDER BY tiebreakers, a stale-response race on
reload) -- both were real bugs, but this was the actual mechanism behind
"my message appears before theirs even though theirs was sent first."
Switched Message.created_at and MessageReaction.created_at from
func.now() to func.clock_timestamp(), which always reflects the actual
moment of execution regardless of how long the transaction has been
open. Migration is a plain column-default change -- no table rewrite, no
lock risk, round-trips cleanly.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Messages can now carry an arbitrary file (MessageFile), parallel to the
existing MessageImage feature rather than a refactor of it. Files serve
with Content-Disposition: attachment to force a download and prevent an
uploaded HTML/SVG from executing same-origin. No content-type allowlist,
same 8MB cap as images for now (a separate size-limit redesign is tracked
as its own issue).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Images live on the app server's local disk (uploads/), served through an
authenticated, room-membership-gated endpoint since rooms can be private.
Uploads are streamed with a byte-count cap, validated as genuine decodable
images with Pillow (not just a spoofed Content-Type), and downscaled to
2000px on the longer side (except GIF, to preserve animation).
Backend: MessageImage model + nullable Message.content/image_id with a
content-or-image CheckConstraint, upload/serve endpoints in rooms.py, WS
message envelope gains image_id, push notification body says "sent an
image" for image-only messages.
Frontend: Composer gets an attach button with upload progress and a
thumbnail chip; MessageList renders images inline with a click-to-zoom
ImageLightbox.
Invite-only FastAPI + SQLAlchemy(async) + Postgres backend (session-cookie
auth via CLI-provisioned accounts, open-room CRUD, single-instance /ws/chat)
and a React + Vite PWA frontend (login, room list, chat view). Backend tests
pass against a local Postgres DB. See README.md and backend/README.md for
setup, and ARCHITECTURE.md for the full phased design.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
ksmithandClaude Sonnet 5