Backend mutation-hardening cluster from the 2026-07-11 mutation-safety audit
sweep (adversarial-reviewer #22/#23), the parallel-safe backend-isolated slice.
audit#22 F4 — standardize post-commit enqueues on CancellationToken.None:
20 command handlers under MediaCollections/, ProgramSchedules/, Playouts/,
Channels/ threaded the request cancellationToken into work that runs AFTER
SaveChangesAsync commits (WriteAsync rebuild/refresh enqueues, mediator.Publish,
reindex, cache Refresh, and post-commit lookups that gate an enqueue). A late
client-disconnect then turns an already-durable commit into a thrown request AND
drops the side effect. Generalizes the #251 deco-handler fix. Excludes
BuildPlayoutHandler (worker/background token, not a client-disconnect token),
the config/FFmpeg multi-upsert handlers (partial-commit case, separate
follow-up), and response-projection reloads (correctly keep the request token).
audit#22 F2 — DeleteChannelHandler/DeletePlayoutHandler now delete the channel
guide {number}.xml through IFileSystem.File.Delete (observable under
MockFileSystem) and BEFORE the commit (a post-commit delete orphans the xml on a
crash; the xml is regenerable on demand, so pre-commit delete is the safe order).
audit#23 F4 — ReplacePlayoutAlternateScheduleItemsHandler rejects an empty item
list in the handler (not only the controller pre-guard) so a direct caller can't
trip the Max()-on-empty crash.
Docs: api-conventions.md §7a (post-commit token convention + boundaries),
decisions.md entry (rationale, sweep scope, #253 PR2-4 coordination note).
Tests: guide-cache-delete-through-FS for both delete handlers, empty-list guard.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Bug 1 (500 on watermark/graphics save): Replace/Add handlers projected the
freshly-built entity graph, whose ProgramScheduleItemWatermark / -GraphicsElement
join rows carry only foreign-key ids — the Watermark/GraphicsElement navs are null,
and Mapper.ProjectToViewModel dereferences them unguarded, throwing an NRE that the
controller surfaced as a 500 on PUT/POST. Both handlers now reload the persisted
item(s) through the read-side include chain before projecting. Extracted that chain
into ProgramScheduleItemQueryExtensions.IncludeScheduleItemDetails() so GET, Replace
and Add share one source of truth.
Masking: PersistItems returned a lazy LanguageExt Map, and the existing round-trip
test only checked .IsRight — never enumerating it, so the deferred NRE never fired.
The new ScheduleItemWriteProjectionTests force enumeration (as the controller's
.ToList()/serialization does) and seed watermark/graphics via a separate context so
the handler's fresh factory context has nothing pre-tracked.
Bug 2 (server side): GetProgramScheduleItemsHandler now .OrderBy(i => i.Index) —
it previously returned id order, which is not index order.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
* initial work on maintaining playout state
* debugging wip
* fix refresh playout logic
* fix failing test
* more fixes
* update changelog
* comment out some debug logs
* comment out more logs
timothy
