CI currently being extended. CI contains a full curl-based test-suite. Semgrep Security Scan used as CodeQL security scanning is unfortunately not available for PHP on GitHub's free tier.

A full-featured calendar plugin for the WinterCMS backend, modelled on Google Calendar. Built on PostgreSQL triggers and native interval/array types for a robust, super high-performance under load, with large data, server-enforced event model.

Requires PostgreSQL 16+. MySQL is not supported — PostgreSQL triggers and interval types are fundamental to the event model.

• Repeating events — daily, weekly, monthly, yearly with frequency multiplier, day mask, and until date
• Container events — parent event bounds all child repeating instances within a date range
• Series editing — update the whole series, from this instance forward, or just this occurrence
• Infinite scroll — navigate months without page reload
• Drag-and-drop — move or resize events; changes persist immediately
• Linux-style permissions — owner / group / other × read / write / delete per event
• Attendees — invite WinterCMS backend users or groups (requires User plugin)
• Multiple calendars — filter by calendar, user, attendance status
• ICS synchronisation — auto-generated .ics feeds, including repeating events and exceptions
• Broadcasting — live updates via WebSockets when another user edits a shared event
• Dirty-write protection — events lock visually and at save when concurrently edited
• All-day events — full-day flag supported
• Optional integrations — Location (location plugin), Messaging (messaging plugin)

• WinterCMS 1.2+ installed
• Acorn module installed as modules/acorn
• PostgreSQL 16+

1. Clone this repository into plugins/acorn/calendar inside your WinterCMS root:

   mkdir -p plugins/acorn
   git clone https://github.com/anewholm/calendar plugins/acorn/calendar

2. Clone the Acorn dependency into modules/acorn:

   git clone https://github.com/anewholm/acorn modules/acorn

3. Add the Acorn module to config/cms.php:

   'loadModules' => ['System', 'Backend', 'Cms', 'Acorn'],

4. Run migrations:

   php artisan winter:up

5. The Calendar section appears in the WinterCMS backend sidebar.

• PostgreSQL only — no MySQL support.
• Broadcasting requires a configured WebSocket server (e.g. Laravel Echo Server or Soketi).
• Attendee features require the User plugin.
• Location features require the Location plugin.

Due to the complexities and processing requirements to project the many types of event repitition, Calendar uses 2 tables: acorn_calendar_event_parts for event details including repeation type & settings, and acorn_calendar_instance for the multiple event instances, keyed by date. For example, an event that repeats weekly for 1 year will have 1 row acorn_calendar_event_parts and 52 rows in acorn_calendar_instance. All time-based querying is on the acorn_calendar_instance primarily. Un-bounded repetition is future, and past, projected limited to the repetition window settings.

Events can have many parts, thus containing a changing event setup over time in to 1 manageable event. For example, an event that changes its repetition frequency from weekly to daily after 1 month would still be 1 event, in acorn_calendar_events, but 2 parts in acorn_calendar_event_parts with a different repetition setting. Titles, descriptions and so on are all stored at the acorn_calendar_event_parts level, thus allowing great flexibility during an event lifetime.

MIT