ConvertToCanonical/ConvertFromCanonical built a fresh CFIConverter
per call, and each annotation converts twice (pos0+pos1) — a book
with 200 highlights re-opened and re-parsed the EPUB 400+ times per
sync, and again per metadata pull. A bounded 8-entry cache keyed by
path now shares converters (the parsing work belongs on the server;
clients stay thin). CFIConverter gained a mutex around its lazily
built spine/doc caches since instances are now shared between
concurrent requests.
Adds CFIConverter.SectionPercentage: book-wide percentage for a CRE
xpointer from the spine char distribution (midpoint of its document)
— the server-side counterpart to dropping per-annotation
getPageFromXPointer lookups from the plugin.
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