JMAP N. Jenkins
Internet-Draft FastMail
Intended status: Standards Track M. Douglass
Expires: October 31, 2019 Spherical Cow Group
April 29, 2019

JMAP for Calendars


This document specifies a data model for synchronising calendar data with a server using JMAP.

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Table of Contents

1. Introduction

JMAP ([I-D.ietf-jmap-core] – JSON Meta Application Protocol) is a generic protocol for synchronising data, such as mail, calendars or contacts, between a client and a server. It is optimised for mobile and web environments, and aims to provide a consistent interface to different data types.

This specification defines a data model for synchronising calendar data between a client and a server using JMAP.

1.1. Notational conventions

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.

Type signatures, examples and property descriptions in this document follow the conventions established in section 1.1 of [I-D.ietf-jmap-core].

Object properties may also have a set of attributes defined along with the type signature. These have the following meanings:

Data types defined in the core specification are used in this document.

1.2. The Date datatypes

Where LocalDate is given as a type, it means a string in the same format as Date, but with the time-offset omitted from the end. The interpretation in absolute time depends upon the time zone for the event, which may not be a fixed offset (for example when daylight saving time occurs). For example, "2014-10-30T14:12:00".

1.3. Terminology

The same terminology is used in this document as in the core JMAP specification.

1.4. Addition to the capabilities object

The capabilities object is returned as part of the standard JMAP Session object; see the JMAP spec. Servers supporting this specification MUST add a property called urn:ietf:params:jmap:calendars to the capabilities object.

The value of this property is an empty object in both the JMAP session capabilities property and an account's accountCapabilities property.

2. Calendars

A Calendar is a named collection of events. All events are associated with one, and only one, calendar.

A Calendar object has the following properties:

2.1. Calendar/get

Standard "/get" method as described in [I-D.ietf-jmap-core] section 5.1. The ids argument may be null to fetch all at once.

2.2. Calendar/changes

Standard "/changes" method as described in [I-D.ietf-jmap-core] section 5.2.

2.3. Calendar/set

Standard "/set" method as described in [I-D.ietf-jmap-core] section 5.3.

A calendar MAY be deleted that is currently associated with one or more events. In this case, the events belonging to this calendar MUST also be deleted. Conceptually, this MUST happen prior to the calendar itself being deleted, and MUST generate a push event that modifies the state of the CalendarEvent type for the account.

3. Calendar events

A CalendarEvent object contains information about an event, or recurring series of events, that takes place at a particular time. It is a JSEvent object, as defined in [I-D.ietf-calext-jscalendar], with the following additional properties:

3.1. CalendarEvent/get

Standard "/get" method as described in [I-D.ietf-jmap-core] section 5.1.

3.2. CalendarEvent/changes

Standard "/changes" method as described in [I-D.ietf-jmap-core] section 5.2

3.3. CalendarEvent/set

Standard "/set" method as described in [I-D.ietf-jmap-core] section 5.3.

When an event is created, updated or destroyed, the server MUST also ensure the following:

3.4. CalendarEvent/copy

Standard "/copy" method as described in [I-D.ietf-jmap-core] section 5.4.

3.5. CalendarEvent/query

Standard "/query" method as described in [I-D.ietf-jmap-core] section 5.5.

3.5.1. Filtering

A FilterCondition object has the following properties:

If zero properties are specified on the FilterCondition, the condition MUST always evaluate to true. If multiple properties are specified, ALL must apply for the condition to be true (it is equivalent to splitting the object into one-property conditions and making them all the child of an AND filter operator).

The exact semantics for matching String fields is deliberately not defined to allow for flexibility in indexing implementation, subject to the following:

3.5.2. Sorting

The following properties MUST be supported for sorting:

3.6. CalendarEvent/queryChanges

Standard "/queryChanges" method as described in [I-D.ietf-jmap-core] section 5.6.

4. Security considerations

All security considerations of JMAP ([I-D.ietf-jmap-core]) apply to this specification. Additional considerations specific to the data types and functionality introduced by this document are described in the following subsections.


5. IANA considerations

5.1. JMAP capability registration for "calendars"

IANA will register the "calendars" JMAP Capability as follows:

Capability Name: urn:ietf:params:jmap:calendars

Specification document: this document

Intended use: common

Change Controller: IETF

Security and privacy considerations: this document, section TODO

6. Normative References

[I-D.ietf-calext-jscalendar] Jenkins, N. and R. Stepanek, "JSCalendar: A JSON representation of calendar data", Internet-Draft draft-ietf-calext-jscalendar-12, March 2019.
[I-D.ietf-jmap-core] Jenkins, N. and C. Newman, "JSON Meta Application Protocol", Internet-Draft draft-ietf-jmap-core-17, March 2019.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017.

Authors' Addresses

Neil Jenkins FastMail PO Box 234, Collins St West Melbourne, VIC 8007 Australia EMail: URI:
Michael Douglass Spherical Cow Group 226 3rd Street Troy, NY 12180 United States of America EMail: URI: