Copenhagen City Hall wedding-slot watcher

Watches the Copenhagen City Hall (Rådhuset) wedding booking calendar and notifies you the moment a new appointment slot appears — so you can grab one before it's gone.

It runs entirely on GitHub Actions (free, no server of your own). By default it notifies you by opening a GitHub issue, which GitHub then emails to you (and pushes to the GitHub mobile app) — no accounts, apps, or secrets to set up. Prefer an instant native phone push? Add an ntfy topic too.

By default it watches the "open to all couples" calendar (Vielsestider åbne for alle brudepar). To watch the Copenhagen-residents calendar instead, see Tuning.

How it works

The booking system (FrontDeskSuite at reservation.frontdesksuite.com) is a multi-step wizard: the time-selection page only works once you've walked through the earlier steps in the same session — a bare request fails with FlowStateIsMissing. So watcher.py:

Starts a session and walks the flow (booking home → calendar page → StartReservation) with a cookie jar, which loads the real availability page.
Parses that page's date headers + time links into concrete slots, e.g. Tuesday October 13, 2026 9:20 a.m.
Compares them against the last run (stored in state.json, which the Action commits back to the repo).
When a new slot matching SLOT_FILTER appears (default: only slots on August 25, the booked wedding date), it sends an ntfy push and opens a GitHub issue @mentioning you. New slots on other dates are logged but ignored. Nothing is sent when there is no change (heartbeats are off by default; set HEARTBEAT_HOURS to re-enable periodic still-alive pings).

A GitHub Actions job checks every ~2.5 minutes by default: each run loops internally for ~50 minutes and then relaunches itself, so the cadence doesn't depend on GitHub's best-effort cron (which stays in place only as a backstop to revive the chain). Tune the interval with the CHECK_SECONDS repo variable (e.g. 60 for one check per minute) — no workflow edit needed. The first run for a URL just records a baseline — it won't spam you with every currently-open slot.

Setup — the zero-config default

Nothing to configure. The watcher uses the Action's built-in token to open the issue, and @mentions the repo owner so you get the email even with default watch settings.

To make sure the alerts reach you:

Confirm your GitHub email notifications are on: Settings → Notifications → Email.
(Optional) Install the GitHub mobile app and enable push for a buzz on your phone.

Run / test it

Actions → Watch wedding slots → Run workflow runs it once. Tick test_notification to fire a one-off test alert and confirm notifications reach you. A normal run records the current availability as a baseline (no alert), then the self-relaunching loop takes over (every CHECK_SECONDS seconds, default 150).

Optional: instant phone push via ntfy

Want a native push instead of / in addition to the email? Add ntfy (free, no account):

Install ntfy (App Store · Google Play).
Subscribe to a hard-to-guess topic name, e.g. cph-wedding-a7f3k9.
Add it as a repo secret: Settings → Secrets and variables → Actions → New repository secret, name NTFY_TOPIC, value = your topic.
Test it: Actions → Run workflow → tick test_notification.

When NTFY_TOPIC is set, alerts go to both ntfy and a GitHub issue.

Tuning what it watches

Set these as repo variables (Settings → Secrets and variables → Actions → Variables) — no code change needed:

Variable	Purpose
`WATCH_URLS`	Which booking flow to watch (comma-separated). See the two calendars below.
`SLOT_REGEX`	Fallback slot pattern for non-FrontDeskSuite pages (unused for Copenhagen).
`CHECK_SECONDS`	Seconds between checks inside the watch loop (default `150`).

The two Copenhagen City Hall calendars (both are StartReservation URLs the watcher knows how to walk):

Open to all couples (default):

https://reservation.frontdesksuite.com/kkvielse/raadhuset/ReserveTime/StartReservation?pageId=c819aa7d-575b-4633-b7c0-a1d425b72390&buttonId=d77d235b-8f65-44e5-bccd-fc93e4edddc8&culture=en&uiCulture=en

Reserved for Copenhagen residents:

https://reservation.frontdesksuite.com/kkvielse/raadhuset/ReserveTime/StartReservation?pageId=3777e58e-1dc4-4ab1-8ee5-1200947805d5&buttonId=140a6acc-0a46-4cfe-805d-de10e077156a&culture=en&uiCulture=en

The pageId/buttonId come from the booking site and may change if the municipality rebuilds its booking pages. If alerts stop, re-grab them: open the booking site, pick the calendar, and copy the "Vælg dato og tidspunkt" link, or run the workflow with the DEBUG=1 repo variable to dump the page.

Running locally

pip install -r requirements.txt
python watcher.py --selftest              # offline unit checks
python watcher.py                         # one real check (prints, no push)
TEST_NOTIFICATION=1 python watcher.py     # test the alert path
DEBUG=1 python watcher.py                 # dump page text/links for debugging

Configuration reference

All settings are environment variables:

Env	Default	Meaning
`GITHUB_TOKEN`	(auto in Actions)	Token used to open the alert issue
`GITHUB_REPOSITORY`	(auto in Actions)	`owner/repo` the issue is opened in
`NOTIFY_MENTION`	repo owner	GitHub username to @mention in the issue
`NTFY_TOPIC`	(unset → GitHub issue only)	ntfy topic for an extra phone push
`NTFY_SERVER`	`https://ntfy.sh`	ntfy server (change for self-hosted)
`WATCH_URLS`	all-couples calendar	Comma-separated booking flow URL(s)
`SLOT_REGEX`	built-in heuristic	Fallback slot pattern (non-FrontDeskSuite)
`STATE_FILE`	`state.json`	Where last-seen slots are stored
`SLOT_FILTER`	`august 25`	Comma-separated substrings; only matching slots alert (empty = all)
`HEARTBEAT_HOURS`	`0` (off)	Hours between still-alive pings when nothing changes
`NOTIFY_ON_FIRST_RUN`	`false`	Alert on the very first run too
`TEST_NOTIFICATION`	`false`	Send one test alert and exit
`DEBUG`	`false`	Dump fetched page text/links to the log

License

MIT