Re: [Jmap] Proposal: split sharing mechanism from JMAP Calendars spec

Joris Baum <> Tue, 15 December 2020 08:22 UTC

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From: Joris Baum <>
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Date: Tue, 15 Dec 2020 09:21:37 +0100
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Subject: Re: [Jmap] Proposal: split sharing mechanism from JMAP Calendars spec
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Hi Neil,

sounds like a good idea. From what I can see one would currently need to 
reuse the CalendarPrincipal and CalendarShareNotification for specs that 
are somehow similar to JMAP for Calendars. I would have done it like 
that in JMAP for Tasks (and probably also Notes). Since CalDAV also 
defines tasks and notes and the JMAP spec relates to CalDAV, reusing 
sharing primitives prefixed by "Calendar" would probably only be 
semi-weird :P. I like dropping the "Calendar" prefix, because it would 
make it clearer that they are generic sharing primitives and not 
specific to calendars.

There may be similar issues with other primitives or methods that are 
defined in JMAP for Calendars. I am currently planning on keeping JMAP 
for Tasks as close as possible to JMAP for Calendars (similar to how 
CalDAV does it). The simplest way that I can see, would be to redefine a 
nearly identical primitive like CalendarEventNotification called 
TaskNotification. I also do not expect most of the method calls to 
deviate all too much from what is defined in JMAP for Calendars. This is 
why I am planning on simply referencing the methods from JMAP for 
Calendars instead of copy+pasting the definition into JMAP for Tasks 
(and probably Notes as well). Maybe there is a better way that I am 
currently not seeing, or we could move even more into a "generic" spec?



On 15.12.20 07:01, Neil Jenkins wrote:
> Hi all,
> The JMAP Calendars draft-in-progress currently defines the 
> CalendarPrincipal and CalendarShareNotification data types under a 
> separate capability. Looking at it, I have come to the conclusion that 
> we should go a step further: drop "Calendar" from the names and split 
> them out into their own spec. These are really generic sharing 
> primitives that could then be referenced by the other specs — e.g. 
> calendars, tasks, mail sharing — to define how you share data of types 
> between entities within a system in a consistent way.
> Please reply with any comments, questions, objections, or agreement 
> with the proposal and I will write up a draft splitting out these data 
> types to propose for acceptance.
> Cheers,
> Neil.
> _______________________________________________
> Jmap mailing list

Joris Baum
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