Deleting a bookmark/highlight/note and then re-adding the same content
at the same position (same dedup key — e.g. the reader's auto-titled
'Bookmark at X%') was silently swallowed: the save hit the tombstone
branch, returned 201 with the deleted row, and the list (which filters
deleted) stayed empty. Bookmarks were further blocked by the
UNIQUE(media_item_id, user_id, title) slot the tombstoned row holds,
and notes had no TTL escape at all.
Tombstones now only block saves that predate them (stale replays from
a device that still has the annotation). A save whose modification
time is newer than max(deleted_at, last_modified_at) — a deliberate
re-create from the web or a device — resurrects the row via the LWW
update queries, which now clear deleted/deleted_at.
AnnotationService is the central service for cross-device annotation sync.
It provides SaveHighlight, SaveNote, and SaveBookmark methods that handle
the full sync lifecycle:
Identity (3-layer):
1. Server UUID (primary key)
2. Per-device native ID stored in device_sync_data JSONB
3. Content dedup_key: sha1(normalize(selection_text) + bucket_position)
- CFI character offsets are stripped for bucketing so the same
highlight at slightly different offsets still deduplicates
- Raw positions are preserved in the DB for precise restoration
Resolution policy (LWW):
- When the incoming annotation has an explicit ModifiedAt timestamp,
last_modified_at wins
- When the device sends zero ModifiedAt (creation time only), field-diff
mode compares content fields (text/color/note/percentage) — if all
match, the save is skipped; if any differ, the save is applied with
server-receive-time as the new last_modified_at
Conflict detection:
- When incoming and existing annotations have different sources (e.g.
koreader vs kobo) and content differs, an auto_resolved sync_conflict
is recorded with both sides' data for audit trail
- Broadcasts a WebSocket conflict notification for real-time UI updates
Tombstone management:
- Delete-wins: tombstoned annotations block recreation from stale pushes
- 30-day TTL before physical purge
- PurgeExpiredTombstones method + StartTombstonePurger goroutine (24h ticker)
Add locators.go with unified bidirectional CFI conversion:
ConvertToCanonical / ConvertFromCanonical
- CRE XPointer <-> standard EPUB CFI (for KOReader)
- KEPUB CFI passthrough (for Kobo)
- Skips non-reflowable formats (PDF, CBZ, fixed-layout EPUBs)
Add 25 unit tests covering:
- Dedup key determinism, text normalization, position sensitivity
- Offset insensitivity (CFI char-offset bucketing)
- Device sync data merge (preserves existing, overwrites same source)
- Cross-source detection
- LWW comparison (newer wins, older skipped, fallback to updated_at)
- Field-diff mode (identical content skipped, changes applied)
- Tombstone TTL constant
- CRE XPointer parsing and classification
- Standard EPUB CFI classification
john-okeefe