Specify extended properties in own contract repo #253
Description
Proposal: Extended Contract
We could specify extended properties that we sync and which are not part of the Android calendar contract (or the task provider contracts) in a separate repository that can be used by others, for instance calendar apps who want to implement the fields.
Core points:
- Separate repository so that others can import the contract as lib or submodule.
- Versioned to make changes clear to implementing apps.
- As client-independent as possible (no hardcoded references to DAVx5 symbols or synctool internals).
- For properties: Contract should include parameters (including unknown parameters) so that they can be re-generated correctly.
- Possibly for CalDAV (events) and CardDAV (contacts).
- Probably scoped only to Android.
The only such property is currently URL, which is documented in the manual: https://manual.davx5.com/integration.html#extended-event-properties
Instead, it should be defined in the new Extended Contract and then the manual should just link to it. A calendar app that wants to implement the property can:
- Include the Extended Contract as dependency.
- Use the defined the fields etc. to view/edit the respective property.
What could be defined
- Properties:
- URL
- ATTACH + attachment operations (CRUD)
- Additional parameters for properties which are defined in Android?
- Free/busy queries
- more CalDAV scheduling