siftlode/backend/app/sync/subscriptions.py
npeter83 f6c5488566 chore: structured timestamped logging across the backend
- uvicorn --log-config (log_config.json): timestamped formatters for uvicorn
  access/error and the app's own "subfeed" loggers (ms precision)
- Log key activity: startup/shutdown, login/denied, token refresh, YouTube API
  errors, subscription imports, sync pause/resume
- Background sync jobs no longer swallow errors silently — failures in RSS poll,
  backfill, enrichment, autotag and resync are logged with tracebacks
2026-06-11 04:26:18 +02:00

120 lines
4.1 KiB
Python

"""Import the authenticated user's YouTube subscriptions and channel metadata."""
import logging
from datetime import datetime, timezone
from sqlalchemy import select
from sqlalchemy.orm import Session
from app.models import Channel, Subscription, User
from app.youtube.client import YouTubeClient, best_thumbnail
log = logging.getLogger("subfeed.sync")
def _to_int(value) -> int | None:
try:
return int(value) if value is not None else None
except (TypeError, ValueError):
return None
def apply_channel_details(db: Session, items: list[dict]) -> None:
now = datetime.now(timezone.utc)
for item in items:
channel = db.get(Channel, item["id"])
if channel is None:
continue
snippet = item.get("snippet", {})
content = item.get("contentDetails", {})
stats = item.get("statistics", {})
topics = item.get("topicDetails", {})
channel.title = snippet.get("title") or channel.title
channel.handle = snippet.get("customUrl")
channel.description = snippet.get("description")
channel.thumbnail_url = (
best_thumbnail(snippet.get("thumbnails")) or channel.thumbnail_url
)
channel.default_language = snippet.get("defaultLanguage")
channel.country = snippet.get("country")
channel.uploads_playlist_id = content.get("relatedPlaylists", {}).get("uploads")
channel.subscriber_count = _to_int(stats.get("subscriberCount"))
channel.video_count = _to_int(stats.get("videoCount"))
channel.topic_categories = topics.get("topicCategories")
channel.details_synced_at = now
def import_subscriptions(db: Session, user: User) -> dict:
"""Pull all subscriptions for `user`, upsert channels + subscription links, prune
channels the user has unsubscribed from on YouTube, and fetch channel details for
any channel we don't have details for yet."""
fetched: dict[str, dict] = {}
new_channels = 0
with YouTubeClient(db, user) as yt:
for sub in yt.iter_subscriptions():
cid = sub.get("channel_id")
if cid:
fetched[cid] = sub
for cid, sub in fetched.items():
channel = db.get(Channel, cid)
if channel is None:
channel = Channel(
id=cid,
title=sub.get("title"),
description=sub.get("description"),
thumbnail_url=sub.get("thumbnail_url"),
)
db.add(channel)
new_channels += 1
sub_row = db.execute(
select(Subscription).where(
Subscription.user_id == user.id, Subscription.channel_id == cid
)
).scalar_one_or_none()
if sub_row is None:
sub_row = Subscription(user_id=user.id, channel_id=cid)
db.add(sub_row)
sub_row.yt_subscription_id = sub.get("yt_subscription_id")
db.flush()
# Prune subscriptions removed on YouTube.
removed = 0
existing = (
db.execute(select(Subscription).where(Subscription.user_id == user.id))
.scalars()
.all()
)
for sub_row in existing:
if sub_row.channel_id not in fetched:
db.delete(sub_row)
removed += 1
db.commit()
# Fetch details for channels that don't have them yet.
need_details = (
db.execute(
select(Channel).where(
Channel.id.in_(fetched.keys()),
Channel.details_synced_at.is_(None),
)
)
.scalars()
.all()
)
detailed = 0
if need_details:
items = yt.get_channels([c.id for c in need_details])
apply_channel_details(db, items)
detailed = len(items)
db.commit()
result = {
"subscriptions": len(fetched),
"channels_new": new_channels,
"channels_detailed": detailed,
"removed_stale": removed,
}
log.info("Subscription import (user %s): %s", user.id, result)
return result