Files
ds-chat/backend/app/services/message_service.py
T
ksmithandClaude Sonnet 5 5643df6bab Add a Files section to room info listing all sent attachments (#33)
Lists files and images actually attached to sent messages in a room,
newest first, with click-through to a lightbox, preview modal, or direct
download depending on type. Queries through messages.image_id/file_id
so an upload that was never sent doesn't show up as a phantom entry.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
2026-08-16 19:57:14 -06:00

138 lines
4.3 KiB
Python

import uuid
from collections import defaultdict
from datetime import datetime, timezone
from sqlalchemy import or_, select
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy.orm import selectinload
from app.models import Message, MessageReaction
from app.schemas.message import ReactionSummary
class MessageNotFoundError(Exception):
pass
class NotMessageAuthorError(Exception):
pass
async def create_message(
db: AsyncSession,
room_id: uuid.UUID,
user_id: uuid.UUID,
content: str | None = None,
image_id: uuid.UUID | None = None,
file_id: uuid.UUID | None = None,
) -> Message:
message = Message(
room_id=room_id, user_id=user_id, content=content, image_id=image_id, file_id=file_id
)
db.add(message)
await db.commit()
await db.refresh(message)
return message
async def edit_message(
db: AsyncSession, message_id: uuid.UUID, editor_id: uuid.UUID, content: str
) -> Message:
message = await db.get(Message, message_id)
if message is None:
raise MessageNotFoundError()
if message.user_id != editor_id:
raise NotMessageAuthorError()
message.content = content
message.edited_at = datetime.now(timezone.utc)
await db.commit()
await db.refresh(message)
return message
async def list_recent_messages(
db: AsyncSession, room_id: uuid.UUID, limit: int = 50
) -> list[Message]:
result = await db.execute(
select(Message)
.where(Message.room_id == room_id)
.options(selectinload(Message.user), selectinload(Message.file))
.order_by(Message.created_at.desc())
.limit(limit)
)
messages = list(result.scalars().all())
messages.reverse()
return messages
async def list_room_attachments(
db: AsyncSession, room_id: uuid.UUID, limit: int = 100
) -> list[Message]:
# Joins through messages.image_id/file_id rather than querying
# message_files/message_images directly -- a file/image is uploaded (and
# gets a row) *before* the message referencing it is ever sent, so an
# upload the user abandoned without sending would otherwise show up as
# a phantom attachment the room never actually saw.
result = await db.execute(
select(Message)
.where(
Message.room_id == room_id,
or_(Message.image_id.isnot(None), Message.file_id.isnot(None)),
)
.options(selectinload(Message.user), selectinload(Message.file), selectinload(Message.image))
.order_by(Message.created_at.desc())
.limit(limit)
)
return list(result.scalars().all())
async def get_reactions_for_messages(
db: AsyncSession, message_ids: list[uuid.UUID]
) -> dict[uuid.UUID, list[ReactionSummary]]:
if not message_ids:
return {}
result = await db.execute(
select(MessageReaction)
.where(MessageReaction.message_id.in_(message_ids))
.order_by(MessageReaction.created_at)
)
# Grouped in Python rather than a GROUP BY/array_agg query -- the row
# count per room-history page is small, and this keeps the ordering
# (first-reacted emoji first, first-reacted user first within it)
# trivial instead of relying on Postgres-specific aggregate ordering.
by_message: dict[uuid.UUID, dict[str, list[str]]] = defaultdict(dict)
for reaction in result.scalars().all():
emoji_map = by_message[reaction.message_id]
emoji_map.setdefault(reaction.emoji, []).append(str(reaction.user_id))
return {
message_id: [
ReactionSummary(emoji=emoji, count=len(user_ids), user_ids=user_ids)
for emoji, user_ids in emoji_map.items()
]
for message_id, emoji_map in by_message.items()
}
async def toggle_reaction(
db: AsyncSession, message_id: uuid.UUID, user_id: uuid.UUID, emoji: str
) -> list[ReactionSummary]:
result = await db.execute(
select(MessageReaction).where(
MessageReaction.message_id == message_id,
MessageReaction.user_id == user_id,
MessageReaction.emoji == emoji,
)
)
existing = result.scalar_one_or_none()
if existing is not None:
await db.delete(existing)
else:
db.add(MessageReaction(message_id=message_id, user_id=user_id, emoji=emoji))
await db.commit()
reactions = await get_reactions_for_messages(db, [message_id])
return reactions.get(message_id, [])