Various compatibility issues

[tobixen]

I've been running the test suite in the python caldav library towards calendar.robur.coop. Since I'm not sure what is intentionally not supported, what is on the roadmap, etc, I will not raise separate issues for each of my findings - except for #28 which seems like an obvious miss.

The results are summarized at python-caldav/caldav#215

Possibly, the most serious issue I found was that searches for a text match will return everything on the calendar.

(Ref python-caldav/caldav#213 an empty response with content type set to text/xml and without a content-length header was causing some problems for the caldav library. The lxml library complains that the empty string is not a valid XML, but I'm not sure if it's a breach of standards or not. Anyway, I've considered this to be a client-side bug and have fixed the library to accept it).

[hannesm]

to preserve the list from python-caldav/caldav#215 here (in order of my priority)

• when doing date searches on tasks, no tasks are returned
• Text match searching does not work too well - the whole calendar is returned. According to the examples in the RFC, even a uid lookup should be performed as a text match search.
• getting errors or empty responses when querying weather the server supports the dav protocol, cdav protocol, and what calendar component types a calendar supports
• In some places, robur returns 403 instead of 404 (possibly to prevent people from scanning resources in a shared name space?)
• I'm getting a 400 when asking for a sync token
• no support for freebusy queries (rfc4791)
• no support for journal entries
• Scheduling is not supported (though it is on the todo-list - at least scheduling by email)