Two coupled bugs surfaced 2026-05-31 by the Subscriptions UI showing
"phantom" subscriptions like `sidecar:patreon:dpmaker`:
1. `SourceService.list()` returned every Source, no filter on URL.
alembic 0022 (2026-05-26) consolidated old per-post-URL Sources into
one canonical row per (artist, platform); when no real campaign URL
was salvageable it rewrote the canonical to `sidecar:<plat>:<slug>`
enabled=false as a disabled anchor. The UI then listed those
anchors as if they were polls — disabled, but visible. Fix: `list()`
excludes `url LIKE 'sidecar:%'` by default; `include_synthetic=True`
opts back in for admin tooling.
2. `importer._source_for_sidecar` picked the lowest-id Source for
(artist, platform). When alembic 0022 had rewritten a per-post row
into a synthetic anchor (lower id) AND the operator later added the
real subscription (higher id), every gallery-dl download silently
attached its Post to the SYNTHETIC instead of the real Source. Fix:
prefer a non-`sidecar:%` URL when one exists; fall back to the
synthetic; only create a new synthetic when nothing exists for
(artist, platform).
alembic 0028 is the data half: for every (artist, platform) with both
a synthetic AND a real Source, pre-merge Post+ImageProvenance
collisions on the canonical, bulk-repoint Posts/ImageProvenance/
DownloadEvent.source_id onto the real Source, and delete the
synthetic. Lone synthetics (no real twin) are left intact — they
anchor real imported content the operator may still want; the
list-filter hides them so they no longer surface as phantoms.
bvandeusen