compass_teams_nhs/docs/phase-6-calendar-notes.md

Phase 6 — the calendar write (Sam's Home Assistant calendar)

Status: code complete and tested; the calendar target needs Sam's decision (AUD-110). The service now writes important school events through the Home Assistant REST API. Nothing is written until a calendar entity is chosen.

What it does

school calendar push selects the important school events that are not in the calendar yet and writes them with the Home Assistant service calendar.create_event. The school is never touched (AGENTS.md §10 rule 1); the only write is to the calendar (rule 7 — no approval needed).

• Important is the Phase 3 classifier: internal/parse/importance.go marks an event high when it is a school event, and normal when it is a routine class period. A Compass week grid writes a class as 5 - 11HLEGB5 - D8 - LHT and an event as End of Year Senior Music Concert - HALL (Senior Music Concert) - KSH, CFR. The first part of a lesson is a period label (5, C, RLE GROUP D).
• Only future events are written: a past lesson is history, not a plan.
• Which events qualify is visible before anything is written:

scripts/calendar-push.sh push --dry-run

Idempotency (a re-run never duplicates)

Two independent guards:

1. The item stores the Home Assistant event id (items.ha_event_uid). An item that already has one is not a candidate again.
2. The event description carries a marker, source: [compass-nhs:<item id>]. A run lists the calendar first and adopts any event that already carries the marker for that item, even when Home Assistant reports no event id.

items.ha_pushed_at records when the item was written.

Fail loudly (FR-12)

A failed calendar write is never swallowed.

• Every attempt is appended to calendar_pushes (ok = 0 plus the error).
• The dashboard shows a Calendar banner: CALENDAR NOT CONFIGURED, CALENDAR WRITE FAILED with the Home Assistant reason, or the healthy state.
• The item screen shows the failure in place of a confirmation.
• scripts/calendar-push.sh push exits non-zero when any write failed.

A failed write leaves the item as a candidate, so the next run retries it.

Configuration (names only — never the values)

Variable	Meaning
SCHOOL_HA_URL	Home Assistant base URL, for example http://192.168.20.30:8123
SCHOOL_HA_TOKEN	long-lived access token (secret)
SCHOOL_HA_CALENDAR_ENTITY	the calendar entity to write to, for example calendar.school
SCHOOL_HA_INSECURE	true to skip TLS verification for the internal .lab certificate
SCHOOL_HA_TIMEOUT	per-request timeout (default 20s)

The values live in environment.d/school-service.env, which is gitignored (AGENTS.md §10 rule 3). The token is never logged, never printed by the CLI and never stored in SQLite.

Commands

scripts/calendar-push.sh entities     # list calendar.* entities and whether they are writable
scripts/calendar-push.sh status       # target, reachability, pending events, last push
scripts/calendar-push.sh push         # write the pending important events
scripts/calendar-push.sh events       # read the calendar back (evidence)
scripts/calendar-push.sh push --dry-run --json

make calendar CALENDAR_ARGS='push --dry-run' runs the same thing.

The item screen has an Add to calendar button for an important future event, and shows in the calendar with the Home Assistant event id once it is written.

The open decision: which calendar entity?

The Home Assistant instance (192.168.20.30, HA 2026.9.4) has three calendar entities, and only two are writable:

Entity	Writable	Backing
calendar.samuelrolfe_googlemail_com	yes	Google, synced into Home Assistant
calendar.birthdays	yes	Google
calendar.holidays_in_australia	no	Google

The brief says Sam's Home Assistant calendar (not Google). Today Home Assistant has no non-Google writable calendar: the local_calendar integration is not installed, and no CalDAV/remote calendar is configured.

So the target must be chosen before the event is written:

1. Add a Local Calendar to Home Assistant (recommended). One Home Assistant config-flow entry creates calendar.school. It is Home-Assistant-local, never touches Google, and is entirely additive. The service then uses SCHOOL_HA_CALENDAR_ENTITY=calendar.school.
2. Use calendar.samuelrolfe_googlemail_com. No Home Assistant change, but every school event also appears in Sam's personal Google Calendar.

The question is posted on AUD-110. The code needs only the configuration line changed once the answer is in.

Where the code lives

internal/calendar/ha.go      Home Assistant REST client (states, create, get, delete)
internal/calendar/sync.go    selection, idempotency, the push log
internal/store/calendar.go   candidates, mark-synced, the append-only push log
internal/store/migrations/003_calendar.sql
cmd/school/calendar.go       `school calendar entities|status|push|events`
internal/web/server.go       the item action + the fail-loud calendar banner
scripts/calendar-push.sh     one-off container runner (no service restart)

Verification

make test    # go test ./...

The tests cover the Home Assistant client against a fake Home Assistant (create, read-back, error mapping), the sync run (write once, adopt by marker, dry run, loud failure, refuse-to-write-blind), the store (candidates, the push log) and the web surface (the action, the CSRF guard, the failure banner).

Not tested here: the live Home Assistant write. That needs the entity decision.