# Docker Support, Meow Expiry and Time-Zone-Aware Clock

**Date:** 2026-08-23
**Project:** ScratchingPost
**Status:** resolved
**Tags:** docker, expiry, scheduling, timezone, clock, sqlite, v1.1.0, v1.1.1

## Context
Jess wanted Scratching Post deployable in Docker as an alternative to IIS, and wanted slides (Meows) to be able to expire automatically after an end date. Running in a container exposed a time-zone problem: containers default to UTC, so expiry checks against `DateTime.Now` fired at the wrong local time. Released as v1.1.0 (Docker + expiry, 2026-08-22) and v1.1.1 (timezone, 2026-08-23).

## Key Decisions
- **`ExpiresAt` on the Slide (Meow) model**, nullable — no expiry by default.
- **Expired Meows are filtered server-side** from both the live display and the playlist API, not hidden client-side.
- **Auto-add the `ExpiresAt` column for existing databases at startup** — because the app uses `EnsureCreated()` (no migrations), existing IIS databases wouldn't otherwise get the new column.
- **Central `Clock` helper instead of raw `DateTime.Now`** — one place that knows the configured time zone; used for expiry checks, the Expired badge, and form text.
- **`TimeZone` setting: blank = host local time** — so existing IIS installs behave exactly as before; Docker image defaults to `UTC` with `tzdata` installed so a named zone can be set.
- **Configurable data directory** so the SQLite DB and uploads live on persistent Docker volumes.

## Technical Details
- `Infrastructure/Clock.cs` — `Clock.Now` returns time in the configured zone; configured from the `TimeZone` setting at startup. Imported into Razor views.
- `appsettings.json` → `TimeZone` (e.g. an IANA zone name; blank = host local).
- Docker: multi-stage `Dockerfile`, `.dockerignore`, `docker-compose.yml` with persistent volumes for DB and uploads; `tzdata` installed in the runtime image.
- Create/Edit Meow forms have a Scheduling card with an expiry date field and text clarifying which time zone it uses.
- Meows list shows an Expires column and an Expired badge (computed with `Clock.Now`).

## Code Changes
- `Models/` — `ExpiresAt` on Slide.
- `Data/` — configurable data directory; startup check adds `ExpiresAt` column if missing.
- Display/playlist controllers — skip expired Meows.
- `Views/` — Scheduling card on Create/Edit; Expires column + Expired badge on list; Clock import.
- `Infrastructure/Clock.cs` — new.
- `Program.cs` — configure Clock from `TimeZone`.
- `Dockerfile`, `.dockerignore`, `docker-compose.yml` — new.
- `README.md` — Docker deployment, Meow expiration, TimeZone setting; version bumps to v1.1.0 / v1.1.1.

## Open Questions / Next Steps
- Add a start date ("publish from") to pair with expiry, if needed.
- **ASK** priority-slide feature still planned.
- If more schema changes accumulate, consider moving from `EnsureCreated()` + ad-hoc column checks to real EF migrations.

## Artifacts
- Release v1.1.1 — `6a6d524` Document TimeZone setting; bump to v1.1.1
- `baac95d` — Use Clock.Now for expiry checks
- v1.1.0 — Docker deployment and Meow expiration
- Repo: https://gitea.hideawaygaming.com.au/jessikitty/ScratchingPost