Internet DRAFT - draft-ietf-calext-jscalendar-icalendar

draft-ietf-calext-jscalendar-icalendar







Calendaring extensions                                       R. Stepanek
Internet-Draft                                                  FastMail
Intended status: Standards Track                             M. Douglass
Expires: 12 January 2023                                             BCS
                                                            11 July 2022


              JSCalendar: Converting from and to iCalendar
               draft-ietf-calext-jscalendar-icalendar-07

Abstract

   This document provides the required methods for converting JSCalendar
   from and to iCalendar.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on 12 January 2023.

Copyright Notice

   Copyright (c) 2022 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents (https://trustee.ietf.org/
   license-info) in effect on the date of publication of this document.
   Please review these documents carefully, as they describe your rights
   and restrictions with respect to this document.  Code Components
   extracted from this document must include Revised BSD License text as
   described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Revised BSD License.






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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   4
     1.1.  Note (to be deleted later)  . . . . . . . . . . . . . . .   4
     1.2.  Motivation  . . . . . . . . . . . . . . . . . . . . . . .   4
     1.3.  Scope and caveats . . . . . . . . . . . . . . . . . . . .   4
     1.4.  Notational Conventions  . . . . . . . . . . . . . . . . .   6
   2.  iCalendar pre-processing  . . . . . . . . . . . . . . . . . .   6
   3.  Translating iCalendar components to JSCalendar  . . . . . . .   7
     3.1.  VALARM  . . . . . . . . . . . . . . . . . . . . . . . . .   7
     3.2.  VCALENDAR . . . . . . . . . . . . . . . . . . . . . . . .  10
     3.3.  VEVENT  . . . . . . . . . . . . . . . . . . . . . . . . .  11
     3.4.  VLOCATION . . . . . . . . . . . . . . . . . . . . . . . .  11
     3.5.  VTIMEZONE, STANDARD, DAYLIGHT . . . . . . . . . . . . . .  12
     3.6.  VTODO . . . . . . . . . . . . . . . . . . . . . . . . . .  13
   4.  Translating iCalendar properties to JSCalendar  . . . . . . .  14
     4.1.  ATTACH  . . . . . . . . . . . . . . . . . . . . . . . . .  14
     4.2.  ATTENDEE  . . . . . . . . . . . . . . . . . . . . . . . .  14
     4.3.  CALSCALE  . . . . . . . . . . . . . . . . . . . . . . . .  17
     4.4.  CATEGORIES  . . . . . . . . . . . . . . . . . . . . . . .  17
     4.5.  CLASS . . . . . . . . . . . . . . . . . . . . . . . . . .  17
     4.6.  COLOR . . . . . . . . . . . . . . . . . . . . . . . . . .  17
     4.7.  COMMENT . . . . . . . . . . . . . . . . . . . . . . . . .  18
     4.8.  COMPLETED . . . . . . . . . . . . . . . . . . . . . . . .  18
     4.9.  CONCEPT . . . . . . . . . . . . . . . . . . . . . . . . .  18
     4.10. CONFERENCE  . . . . . . . . . . . . . . . . . . . . . . .  19
     4.11. CONTACT . . . . . . . . . . . . . . . . . . . . . . . . .  19
     4.12. CREATED . . . . . . . . . . . . . . . . . . . . . . . . .  19
     4.13. DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . .  20
     4.14. DTEND, DTSTART, DUE, DURATION . . . . . . . . . . . . . .  21
     4.15. ESTIMATED-DURATION  . . . . . . . . . . . . . . . . . . .  24
     4.16. EXDATE  . . . . . . . . . . . . . . . . . . . . . . . . .  24
     4.17. EXRULE  . . . . . . . . . . . . . . . . . . . . . . . . .  24
     4.18. DTSTAMP and LAST-MODIFIED . . . . . . . . . . . . . . . .  24
     4.19. GEO . . . . . . . . . . . . . . . . . . . . . . . . . . .  25
     4.20. IMAGE . . . . . . . . . . . . . . . . . . . . . . . . . .  25
     4.21. LOCATION  . . . . . . . . . . . . . . . . . . . . . . . .  25
     4.22. METHOD  . . . . . . . . . . . . . . . . . . . . . . . . .  25
     4.23. ORGANIZER . . . . . . . . . . . . . . . . . . . . . . . .  26
     4.24. PERCENT-COMPLETE  . . . . . . . . . . . . . . . . . . . .  26
     4.25. PRIORITY  . . . . . . . . . . . . . . . . . . . . . . . .  28
     4.26. PRODID  . . . . . . . . . . . . . . . . . . . . . . . . .  29
     4.27. RECURRENCE-ID . . . . . . . . . . . . . . . . . . . . . .  29
     4.28. RELATED-TO  . . . . . . . . . . . . . . . . . . . . . . .  29
     4.29. REQUEST-STATUS  . . . . . . . . . . . . . . . . . . . . .  30
     4.30. RESOURCES . . . . . . . . . . . . . . . . . . . . . . . .  30
     4.31. RDATE . . . . . . . . . . . . . . . . . . . . . . . . . .  31
     4.32. RRULE . . . . . . . . . . . . . . . . . . . . . . . . . .  31



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     4.33. SEQUENCE  . . . . . . . . . . . . . . . . . . . . . . . .  35
     4.34. STATUS  . . . . . . . . . . . . . . . . . . . . . . . . .  35
     4.35. STRUCTURED-DATA . . . . . . . . . . . . . . . . . . . . .  35
     4.36. SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . .  36
     4.37. TRANSP  . . . . . . . . . . . . . . . . . . . . . . . . .  36
     4.38. UID . . . . . . . . . . . . . . . . . . . . . . . . . . .  37
     4.39. URL . . . . . . . . . . . . . . . . . . . . . . . . . . .  37
   5.  Translating non-standard iCalendar to JSCalendar  . . . . . .  37
     5.1.  urn:ietf:rfcXXXX#components . . . . . . . . . . . . . . .  37
     5.2.  urn:ietf:rfcXXXX#properties . . . . . . . . . . . . . . .  38
     5.3.  urn:ietf:rfcXXXX#parameters . . . . . . . . . . . . . . .  39
     5.4.  urn:ietf:rfcXXXX#prop . . . . . . . . . . . . . . . . . .  40
   6.  Translating iCalendar Recurrences . . . . . . . . . . . . . .  40
     6.1.  Translating iCalendar Recurrences: Simple objects with
           overrides . . . . . . . . . . . . . . . . . . . . . . . .  40
     6.2.  Translating iCalendar Recurrences: Overrides with no
           master  . . . . . . . . . . . . . . . . . . . . . . . . .  41
   7.  Translating iCalendar: Further examples . . . . . . . . . . .  41
     7.1.  Recurring event with ATTACH . . . . . . . . . . . . . . .  41
     7.2.  Simple event with CONTACT . . . . . . . . . . . . . . . .  43
     7.3.  Simple event with RESOURCES . . . . . . . . . . . . . . .  45
     7.4.  Recurring event.  Attendees only in overrides . . . . . .  45
   8.  Translating JSCalendar objects to iCalendar . . . . . . . . .  48
     8.1.  Event . . . . . . . . . . . . . . . . . . . . . . . . . .  48
     8.2.  Group . . . . . . . . . . . . . . . . . . . . . . . . . .  49
     8.3.  Task  . . . . . . . . . . . . . . . . . . . . . . . . . .  49
   9.  Translating JSCalendar properties to iCalendar  . . . . . . .  50
     9.1.  alerts  . . . . . . . . . . . . . . . . . . . . . . . . .  50
       9.1.1.  action  . . . . . . . . . . . . . . . . . . . . . . .  50
       9.1.2.  title and description . . . . . . . . . . . . . . . .  51
       9.1.3.  trigger . . . . . . . . . . . . . . . . . . . . . . .  51
       9.1.4.  todo  . . . . . . . . . . . . . . . . . . . . . . . .  52
       9.1.5.  Example event with alerts . . . . . . . . . . . . . .  52
     9.2.  categories  . . . . . . . . . . . . . . . . . . . . . . .  54
     9.3.  color . . . . . . . . . . . . . . . . . . . . . . . . . .  54
     9.4.  created . . . . . . . . . . . . . . . . . . . . . . . . .  55
     9.5.  duration  . . . . . . . . . . . . . . . . . . . . . . . .  55
     9.6.  estimatedDuration . . . . . . . . . . . . . . . . . . . .  55
     9.7.  keywords  . . . . . . . . . . . . . . . . . . . . . . . .  56
     9.8.  locations . . . . . . . . . . . . . . . . . . . . . . . .  56
       9.8.1.  coordinates . . . . . . . . . . . . . . . . . . . . .  57
       9.8.2.  description . . . . . . . . . . . . . . . . . . . . .  57
       9.8.3.  links . . . . . . . . . . . . . . . . . . . . . . . .  57
       9.8.4.  locationTypes . . . . . . . . . . . . . . . . . . . .  57
       9.8.5.  name  . . . . . . . . . . . . . . . . . . . . . . . .  57
       9.8.6.  relativeTo  . . . . . . . . . . . . . . . . . . . . .  57
       9.8.7.  timeZone  . . . . . . . . . . . . . . . . . . . . . .  57
       9.8.8.  uid . . . . . . . . . . . . . . . . . . . . . . . . .  58



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     9.9.  participants  . . . . . . . . . . . . . . . . . . . . . .  58
     9.10. timezones . . . . . . . . . . . . . . . . . . . . . . . .  58
   10. Translating non-standard JSCalendar to iCalendar  . . . . . .  59
     10.1.  New iCalendar properties . . . . . . . . . . . . . . . .  60
       10.1.1.  X-RFCXXXX-JSPROP Property  . . . . . . . . . . . . .  60
       10.1.2.  X-RFCXXXX-PROP Property  . . . . . . . . . . . . . .  61
     10.2.  New iCalendar Parameters . . . . . . . . . . . . . . . .  64
       10.2.1.  X-RFCXXXX-JSNAME Parameter . . . . . . . . . . . . .  64
   11. JsCalendar base spec updates  . . . . . . . . . . . . . . . .  64
   12. Security Considerations . . . . . . . . . . . . . . . . . . .  65
   13. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  65
   14. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .  65
   15. References  . . . . . . . . . . . . . . . . . . . . . . . . .  65
     15.1.  Normative References . . . . . . . . . . . . . . . . . .  65
     15.2.  Informative References . . . . . . . . . . . . . . . . .  66
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  67

1.  Introduction

1.1.  Note (to be deleted later)

   This is still very much a work in progress.  There are
   implementations of the mapping but there may be changes over the
   coming weeks.

1.2.  Motivation

   The JSCalendar [RFC8984] data format is used to represent calendar
   data, and is meant as an alternative to the widely deployed iCalendar
   [RFC5545] data format.

   While new calendaring services and applications might use JSCalendar
   as their main data format to exchange calendaring data, they are
   likely to interoperate with services and clients that just support
   iCalendar.  Similarly, existing calendaring data is stored in
   iCalendar format in databases and other calendar stores, and
   providers and users might want to represent this data also in
   JSCalendar.  Lastly, there is a requirement to preserve custom
   iCalendar properties that have no equivalent in JSCalendar when
   converting between these formats.

   To support these use cases, this document provides the required
   approach when converting JSCalendar data from and to iCalendar.

1.3.  Scope and caveats

   JSCalendar and iCalendar have a lot of semantics in common, but they
   are not interchangeable formats:



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   *  JSCalendar contains a richer data model to express calendar
      information such as event locations and participants.  while
      future iCalendar extensions may allow a direct mapping, for now
      there may be no representation directly in iCalendar of some
      properties.  These values may have to be extracted from a full
      copy of the iCalendar format provided as a property in the
      JSCalendar data.

   *  iCalendar may contain arbitrary, non-standardised data with custom
      properties/attributes.  These will be translated using the same
      approach as jCal.

   *  iCalendar has some obsolete features that have been removed from
      JSCalendar due to not being useful and/or supported in the real
      world (e.g. custom email alerts to send to random people).
      Translating these may lose some of the original fidelity.

   *  Implementations may use a custom property to store data that could
      not be mapped directly in either direction in the original or a
      custom format, however this is not interoperable.

   *  JSCalendar supports fractional seconds in time values whereas
      iCalendar does not.  A subsequent specification will define how
      fractional seconds can be represented in iCalendar.

   Accordingly, this document defines a canonical translation between
   iCalendar and JSCalendar, and implementations MUST follow the
   approaches specified here when iCalendar data is represented in
   JSCalendar and vice-versa.

   This document defines mappings for the following specifications.

   *  Internet Calendaring and Scheduling Core Object Specification
      (iCalendar) [RFC5545]

   *  iCalendar Transport-Independent Interoperability Protocol (iTIP)
      [RFC5546]

   *  New Properties for iCalendar [RFC7986]

   *  Event Publishing Extensions to iCalendar [RFC9073]

   *  Support for iCalendar Relationships
      [draft-ietf-calext-ical-relations]

   *  "VALARM" Extensions for iCalendar [RFC9074]





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   Therefore all of these specifications MUST be implemented to follow
   this specification.

1.4.  Notational Conventions

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

2.  iCalendar pre-processing

   iCalendar uses a line-folding mechanism to limit lines of data to a
   maximum line length (typically 75 octets) to ensure the maximum
   likelihood of preserving data integrity as it is transported via
   various means (e.g., email) -- see Section 3.1 of [RFC5545].

   iCalendar data uses an "escape" character sequence for text values
   and property parameter values.  See Sections 3.1 and 3.3 of [RFC5545]
   as well as [RFC6868].

   There is a subtle difference in the number representations between
   JSON and iCalendar.  While in iCalendar, a number may have leading
   zeros, as well as a leading plus sign; this is not the case in JSON.
   Numbers should be represented in whatever way needed for the
   underlying format.

   When converting from iCalendar to JSCalendar: First, iCalendar lines
   MUST be unfolded.  Afterwards, any iCalendar escaping MUST be
   unescaped.  Finally, JSON escaping, as described in Section 7 of
   [RFC8259], MUST be applied.  The reverse order applies when
   converting from JSCalendar to iCalendar, which is further described
   in Section ?.

   iCalendar uses a base64 encoding for binary data.  However, it does
   not restrict the encoding from being applied to non-binary value
   types.  So, the following rules are applied when processing a
   property with the "ENCODING" property parameter set to "BASE64":

   *  If the property value type is "BINARY", the base64 encoding MUST
      be preserved.

   *  If the value type is not "BINARY", the "ENCODING" property
      parameter MUST be removed, and the value MUST be base64 decoded.

   When base64 encoding is used, it MUST conform to Section 4 of
   [RFC4648], which is the base64 method used in [RFC5545].





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   One key difference in the formatting of values used in iCalendar and
   JSCalendar is that, in JSCalendar, the specification uses date/time
   values aligned with the extended format of [ISO.8601.2004], which is
   more commonly used in Internet applications that make use of the JSON
   format.  The sections of this document describing the various date
   and time formats contain more information on the use of the complete
   representation, reduced accuracy, or truncated representation.

3.  Translating iCalendar components to JSCalendar

   This section is an alphabetic list of [RFC5545] components and how
   they are mapped to JSCalendar.

   At present VFREEBUSY and VJOURNAL are not mapped in jscalendar.

3.1.  VALARM

   An [RFC5545] VALARM component is mapped to a member of a JSCalendar
   "alerts" object with a type of "Alert" and a small id.

     BEGIN: VEVENT
     ...
     BEGIN: VALARM
     ...
     END: VALARM
     BEGIN: VALARM
     ...
     END: VALARM
     END: VEVENT

     maps to

     {
       "@type": "Event",
       ...
       "alerts": {
         "1": {
           "@type": "Alert",
           ...
         },
         "2": {
           "@type": "Alert",
           ...
         }
       }
     }





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   The [RFC5545] VALARM has a number of problems which are not carried
   over into JSCalendar.  Clients tend to choose how, and in some cases
   when to notify the user.

   For example, if the user has a smart-watch they may get tapped on the
   wrist.  The method of notification may depend on which device is
   being used and the context, for example a meeting or driving.

   Also, many clients are taking into consideration the travel time and
   notifying the user earlier if it seems necessary.

   Specifying that a client should send emails to all attendees is both
   annoying and dangerous.  Attendees have their own preferences for how
   and when they should be notified.

   Accordingly, the specification only allows for "display" and "email"
   actions and - other than specifying when - does not allow much else.
   Clients and/or servers will generally use the associated event or
   task title as identification.  User preferences generally indicate
   what actions they prefer.

   Any ATTENDEE properties in the VALARM MUST be ignored.

   An [RFC5545] ACTION property can take the defined values "AUDIO" /
   "DISPLAY" / "EMAIL" whereas the JSCalendar "action" property only
   supports "display" and "email".

   An "AUDIO" alarm SHOULD be mapped to a "display" alert.  Any
   attachment MUST be ignored.

   The iCalendar DESCRIPTION property is required for both ACTION:EMAIL
   and ACTION:DISPLAY.  Additionally, the iCalendar SUMMARY property is
   required for ACTION:EMAIL.

   Store the SUMMARY in the optional alert title property and the
   DESCRIPTION is the alert description property.

   The [RFC5545] example VALARMs will be mapped as follows, assuming
   they are all in the same event:

     BEGIN:VEVENT
     DTSTAMP:20200522T142047Z
     DTSTART;TZID=America/New_York:20220622T120000
     DURATION:PT1H
     SUMMARY:event with alarms
     UID:6252D6C40A8308BFE25BBEFsimple-alarms-1
     BEGIN:VALARM
     TRIGGER;VALUE=DATE-TIME:20220508T120000Z



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     REPEAT:4
     DURATION:PT15M
     ACTION:AUDIO
     ATTACH;FMTTYPE=audio/basic:ftp://example.com/pub/
      sounds/bell-01.aud
     END:VALARM
     BEGIN:VALARM
     TRIGGER:-PT30M
     REPEAT:2
     DURATION:PT15M
     ACTION:DISPLAY
     DESCRIPTION:Breakfast meeting with executive\n
      team at 8:30 AM EST.
     END:VALARM
     BEGIN:VALARM
     TRIGGER;RELATED=END:-P2D
     ACTION:EMAIL
     ATTENDEE:mailto:john_doe@example.com
     SUMMARY:*** REMINDER: SEND AGENDA FOR WEEKLY STAFF MEETING ***
     DESCRIPTION:A draft agenda needs to be sent out to the attendees
       to the weekly managers meeting (MGR-LIST). Attached is a
       pointer the document template for the agenda file.
     ATTACH;FMTTYPE=application/msword:http://example.com/
      templates/agenda.doc
     END:VALARM
     END:VEVENT

     maps to

     {
       "@type": "Group",
       "prodId": "//example.org//Example V3.14//EN",
       "entries": [
         {
           "@type": "Event",
           "alerts": {
             "1": {
               "@type": "Alert",
               "action": "display",
               "trigger": {
                 "@type": "AbsoluteTrigger",
                 "when": "2022-05-08T12:00:00Z"
               }
             },
             "2": {
               "@type": "Alert",
               "action": "display",
               "description": "Breakfast meeting with executive\n



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                          team at 8:30 AM EST.",
               "trigger": {
                 "@type": "OffsetTrigger",
                 "offset": "-PT30M"
               }
             },
             "3": {
               "@type": "Alert",
               "action": "email",
               "title": "*** REMINDER: SEND AGENDA FOR WEEKLY
                         STAFF MEETING ***",
               "description": "A draft agenda needs to be sent out to
                       the attendees to the weekly managers meeting
                       (MGR-LIST). Attached is a pointer the document
                       template for the agenda file.",
               "trigger": {
                 "@type": "OffsetTrigger",
                 "offset": "-P-2D",
                 "relativeTo": "end"
               }
             }
           },
           "created": "2022-05-02T20:04:12Z",
           "start": "2022-06-22T12:00:00",
           "timeZone": "America/New_York",
           "duration": "PT1H",
           "title": "event with alarms",
           "uid": "6252D6C40A8308BFE25BBEFsimple-alarms-1"
         }
       ]
     }

   Note that the ATTENDEE, DURATION and REPEAT properties have been
   dropped.

3.2.  VCALENDAR

   A [RFC5545] VCALENDAR component may be mapped to a JSCalendar object
   with a type of "Group".












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     BEGIN: VCALENDAR
     PRODID:-//ABC Corporation//NONSGML My Product//EN
     ...
     END: VCALENDAR

     maps to

     {
       "@type": "Group",
       "prodid": "-//ABC Corporation//NONSGML My Product//EN",
       ...
     }

   Note that a single Event or Task MAY be converted without a
   surrounding Group if the VCALENDAR component only contains PRODID and
   CALSCALE properties.  In this case the prodid can go in the Event or
   Task.  The CALSCALE property is dropped - there is no equivalence in
   JSCalendar.

3.3.  VEVENT

   A [RFC5545] VEVENT component is mapped to a JSCalendar object with a
   type of "Event".

     BEGIN: VEVENT
     ...
     END: VEVENT

     maps to

     {
       "@type": "Event",
       ...
     }

3.4.  VLOCATION

   A [RFC9073] VLOCATION component is mapped to a JSCalendar object with
   a type of "Location".  Any properties within the VLOCATION must be
   mapped as described below.











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     BEGIN: VEVENT
     ...
     BEGIN: VLOCATION
     ...
     END: VLOCATION
     END: VEVENT

     maps to

     {
       "@type": "Event",
       ...
        "locations": {
          "1": {
            "@type": "Location",
            ...
          }
        }
     }

3.5.  VTIMEZONE, STANDARD, DAYLIGHT

   A [RFC5545] VTIMEZONE component is mapped to a member of a JSCalendar
   "timezones" object with a type of "TimeZone" and an id which follows
   the restrictions specified.

   The STANDARD and DAYLIGHT components map to JSCalendar TimeZoneRule
   objects as members of the

   Note that

   *  There is no current approach for defining standalone sets of
      timezones.

   *  Timezones defined in the IANA timezone database SHOULD NOT be
      redefined in the object.  Only custom timezones will be defined.















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     BEGIN: VTIMEZONE
     TZID: Example/Somewhere
     ...
     END: VTIMEZONE
     BEGIN: VTIMEZONE
     TZID: Example/Somewhere-else
     ...
     END: VTIMEZONE
     BEGIN: VEVENT
     ...
     END: VEVENT

     maps to

     {
       "@type": "Event",
       ...
       "timezones": {
         "/Example/Somewhere: {
           "@type": "TimeZone",
           "tzId": "Example/Somewhere",
           ...
         },
         "/Example/Somewhere-else": {
           "@type": "TimeZone",
           "tzId": "Example/Somewhere-else",
           ...
         }
       }
     }

3.6.  VTODO

   A [RFC5545] VTODO component is mapped to a JSCalendar object with a
   type of "Task".

     BEGIN: VTODO
     ...
     END: VTODO

     maps to

     {
       "@type": "Task",
       ...
     }





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4.  Translating iCalendar properties to JSCalendar

   This section is an alphabetic list of [RFC5545] and [RFC7986]
   properties and how they are mapped to JSCalendar.

4.1.  ATTACH

   A [RFC5545] ATTACH allows for two types of attachment:

   *  A uri value

   *  A binary value

   Both map to a JSCalendar "link" object with a "rel" of "enclosure"
   and the "href" set to the value of the property.

   If the FMTTYPE parameter is set then add a JSCalendar "contentType"
   property to the link object.

   For a binary value use a base64 data uri.

   For an example of a recurring event with ATTACH see Section 7.1

4.2.  ATTENDEE

   An [RFC5545] ATTENDEE maps to the JSCalendar "participant" property
   with a JSCalendar "role" of "attendee".  The value for role should
   always be set.

   In the simplest case a JSCalendar "participant" property will be
   created and added to the JSCalendar "participants" property.

   The value of the ATTENDEE property is used to add an "imip" method to
   the JSCalendar "sendTo" property.  The value of the entry will be the
   ATTENDEE property value.

   For example:














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     ...
     ATTENDEE:mailto:user01@example.org
     ...

     maps to

     {
     ...
         "participants": {
           "be450b70-9bf7-4f6e-8f65-971ede566ce3": {
             "@type": "Participant",
             "sendTo": {
               "imip": "mailto:user01@example.org"
             },
     ...
     }

   The attendee parameters are mapped to JSCalendar "participant"
   properties as follows:

   CN:  The value of the CN parameter is used to set the JSCalendar
      "name" property.

   CUTYPE:  This maps on to the JSCalendar "kind" property as follows:

      INDIVIDUAL  "individual"

      GROUP  "group"

      RESOURCE  "resource"

      ROOM  "location"

      UNKNOWN  No value

      Any other value should be converted to lower case and assigned to
      the JSCalendar "kind" property.

   DELEGATED-FROM:  Split the value at any commas and add each resulting
      element to the JSCalendar "delegatedFrom" property

   DELEGATED-TO:  Split the value at any commas and add each resulting
      element to the JSCalendar "delegatedFrom" property

   DIR:  If non-null look in the participant "links" property for a
      JSCalendar "link" property with an href with the same value as the
      DIR parameter.  You may need to search the current override and
      the master.



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      If none is found create a new one with the JSCalendar "href"
      property set to the value of the DIR parameter and the JSCalendar
      "rel" property set to "alternate"

   LANG:  set the JSCalendar "language" property to the value of the
      LANG parameter.

   MEMBER:  If this is set there should be a corresponding ATTENDEE
      object with a value equal to the value of the member parameter.
      If not it is appropriate to skip this parameter.

      If there is a corresponding ATTENDEE then there should be a
      corresponding JSCalendar "participant" property.  This suggests
      that CUTYPE=GROUP ATTENDEE properties should be processed ahead of
      the others.

      Locate the JSCalendar "participant" property for the group.  This
      may be in the current override or in the master.  Add the id to
      the current participants JSCalendar "memberOf" property.

   PARTSTAT:  If the PARTSTAT parameter is set and is not "NEEDS-ACTION"
      then set the JSCalendar "participationStatus" property to the
      lower-cased value of the PARTSTAT.

   ROLE:  This is mapped to the JSCalendar "roles" property as follows:

      CHAIR  "attendee" and "chair"

      REQ-PARTICIPANT  "attendee"

      OPT-PARTICIPANT  "attendee" and "optional"

      NON-PARTICIPANT  "informational"

      Any other value should be converted to lower case and added to the
      JSCalendar "roles" property.

   RSVP:  If the value of the RSVP parameter is TRUE set the JSCalendar
      "expectReply" property to "true" otherwise omit it.

   SCHEDULE-AGENT:  If the value is "CLIENT" (ignoring case) set the
      JSCalendar "scheduleAgent" property to "client" otherwise omit it.

   SCHEDULE-FORCE-SEND:  Set the JSCalendar "scheduleForceSend" property
      to the lower-cased value of the [RFC6638] SCHEDULE-FORCE-SEND
      parameter.

   SCHEDULE-STATUS:  Split the value at any commas and add each



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      resulting element to the JSCalendar "scheduleStatus" property.

   SENT-BY:  The value of the SENT-BY parameter is used to set the
      JSCalendar "invitedBy" property.

4.3.  CALSCALE

   A [RFC5545] CALSCALE has no equivalence in JSCalendar.  It is
   ignored.

4.4.  CATEGORIES

   These map on to the JSCalendar "keywords" property with each category
   being the key to an entry.

     ...
     CATEGORIES:APPOINTMENT,EDUCATION
     CATEGORIES:MEETING
     ...

     maps to

     ...
     "keywords": {
          "APPOINTMENT": true,
          "EDUCATION": true,
          "MEETING": true
        },
     ...

4.5.  CLASS

   Maps to the "privacy" property.  The iCalendar property value maps to
   the JSCalendar value as follows:

   CONFIDENTIAL  "secret"

   PRIVATE  "private"

   PUBLIC  "public"

   iana-token and x-name  verbatim copy

4.6.  COLOR

   The COLOR property is defined in [RFC7986] and maps to the JSCalendar
   "color" property.  Copy the value verbatim.




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4.7.  COMMENT

   There is no direct mapping for this property which may appear
   multiple times in [RFC5545].

   For a scheduling reply it is presumably a message by the participant
   so the value or values should be used to set the JSCalendar
   "participantComment" property.

4.8.  COMPLETED

   Set the JSCalendar "progress" property to "completed" and the
   "progressUpdated" property to the reformatted date/time.

     ...
     COMPLETED: "20101010T101010Z"
     ...

     maps to

     ...
     "progressUpdated": "2010-10-10T10:10:10Z",
     "progress": "completed",
     ...

4.9.  CONCEPT

   This [draft-ietf-calext-ical-relations] property may appear multiple
   times in components.

   Each instance of the property is mapped on to a member of the
   JSCalendar "categories" property.

     ...
     CONCEPT:http://example.com/event-types/arts/music
     CONCEPT:http://example.com/performance-types/arts/live
     ...

     maps to

     ...
     "categories": {
       "http://example.com/event-types/arts/music": true,
       "http://example.com/performance-types/arts/live": true
     }
     ...





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4.10.  CONFERENCE

   Maps to a "VirtualLocation" object.  The property value maps to the
   "uri" property of the virtual location.

   Mapping parameters:

   FEATURE:  Maps to the "features" property of the virtual location.

   LABEL:  Maps to the "name" property of the virtual location.

   LANGUAGE:  No mapping.

4.11.  CONTACT

   A CONTACT property is mapped on to a participant object with a
   "roles" property of "contact".  The value of the property is used to
   set the jscalendar participant "name" property.

   QUESTIONS - what to use for the id?  I have a uid but that's my
   implementation.  There may be multiple CONTACT properties.  If we
   create PARTICIPANT objects going the other way - how to link them -
   "name" == CONTACT value?

   Mapping parameters:

   ALTREP  Use the same process as for the ATTENDEE DIR parameter:
      create a link property with the "rel" property set to "alternate"
      and the "href" property set to the value of the ALTREP parameter.
      Then add the link to the participants "links" property.

   LANG  Set the participants "language" property.

   For an example see Section 7.2

4.12.  CREATED

   The CREATED property is mapped on to a "created" property with a json
   formatted form of the date.  Example:












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     BEGIN:VEVENT
     ...
     CREATED:19960329T133000Z
     ...
     END:VEVENT

     maps to

     {
       "@type": "Event",
       ...
       "created": "1996-03-29T13:30"00Z",
       ...
     }

4.13.  DESCRIPTION

   Copy the value, preprocessed according to Section 2 into the
   "description" property.

   Mapping parameters:

   ALTREP  No mapping.

   LANG  Use the "locale" property.

   Example:
























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     BEGIN:VEVENT
     ...
     DESCRIPTION:We are having a meeting all this week at 12 pm fo
      r one hour\, with an additional meeting on the first day 2 h
      ours long.\nPlease bring your own lunch for the 12 pm meetin
      gs.
     ...
     END:VEVENT

     maps to

     {
       "@type": "Event",
       ...
       "description": // Note: comments and string concatenation are not
               // allowed per the JSON specification and is used here
               // to avoid long lines.
           "We are having a meeting all this week at 12 pm for one " +
           "hour, with an additional meeting on the first day 2 " +
           "hours long.\nPlease bring your own lunch for the 12 pm " +
           "meetings.",
       ...
     }

4.14.  DTEND, DTSTART, DUE, DURATION

   If the DTSTART is a DATE only property then add the JSCalendar
   showWithoutTime property with the value set to "true".  The
   JSCalendar "start" property is set with zero time values.

   If the DTSTART has a TZID parameter then set the JSCalendar
   "timeZone" property to the value of TZID.

   If the DTSTART has a UTC value then set the JSCalendar "timeZone"
   property to the value "Etc/UTC".  The JSCalendar "start" property is
   set without any UTC indicator.

   JSCalendar has no equivalent to DTEND.  If the component has a DTEND
   then calculate a value for "DURATION" from that property and DTSTART
   and proceed as below.

   If the DTEND has a TZID parameter with a value that differs from the
   DTSTART TZID parameter then a "location" object should be created
   with a "relativeTo" property set to "end" and a "timezone" property
   set to the value of the "TZID" parameter.

   Note that a task is not required to have a DTSTART so the JSCalendar
   "timezone" property needs to be set from the DUE property.



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   Convert a DURATION property to the JSCalendar duration.

   Example - DTSTART and DTEND in same timezone:

     BEGIN:VEVENT
     ...
     DTSTART;TZID=America/New_York:20170315T150000
     DTEND;TZID=America/New_York:20170315T160000

     ...
     END:VEVENT

     maps to

     {
       "@type": "Event",
       ...
       "start": "2017-03-15T15:00:00",
       "timeZone": "America/New_York",
       "duration": "PT1H"
       ...
     }

   Example - DTSTART and DTEND in different timezone:



























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     BEGIN:VEVENT
     ...
     DTSTART;TZID=America/New_York:20170315T150000
     DTEND;TZID=America/LosAngeles:20170315T190000

     ...
     END:VEVENT

     maps to

     {
       "@type": "Event",
       ...
       "start": "2017-03-15T15:00:00",
       "timeZone": "America/New_York",
       "duration": "PT7H"
       ...
       "locations": {
          "1": {
                 "@type": "location",
                 "relatedTo": "end",
                 "timeZone": "America/Los_Angeles"
               }
          }
     }

   Example - 3 day event:

     BEGIN:VEVENT
     ...
     DTSTART;VALUE=DATE:20210315
     DTEND;VALUE=DATE:20210318

     ...
     END:VEVENT

     maps to

     {
       "@type": "Event",
       ...
       "start": "2017-03-15T00:00:00",
       "duration": "P3D",
       "showWithoutTime": true,
       ...
     }





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4.15.  ESTIMATED-DURATION

   Copy the ESTIMATED-DURATION value into the JSCalendar
   "estimatedDuration" property.

   For example:

     ...
     ESTIMATED-DURATION:PT18H
     ...

     maps to

     ...
     "estimatedDuration": "PT18H"
     ...

4.16.  EXDATE

   Create a patch object with the recurrence id set from the EXDATE
   value.  Add a single JSCalendar "excluded" property with the value
   set to true.  There MUST NOT be any other properties set - other than
   "@type".

4.17.  EXRULE

   Maps to the "excludedRecurrenceRules" property.  Also see
   Section 4.32.

4.18.  DTSTAMP and LAST-MODIFIED

   The mapping depends on whether or not the component is a scheduling
   entity.

   Not a scheduling entity:  The [RFC5545] DTSTAMP and LAST-MODIFIED
      properties have essentially the same meaning.  If both are present
      use the value of the latest for the "updated" property.  Otherwise
      set from whichever is present.

   Is a scheduling entity:  DTSTAMP should be used to set the
      "ScheduleUpdated" property in the "participant" object for the
      attendee.

      If present LAST-MODIFIED should be used to set the "updated"
      property - otherwise set it from the DTSTAMP.






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4.19.  GEO

   Maps to a Location object, with only the "coordinates" property set.
   Note that the JSCalendar coordinates property value MUST be a valid
   "geo" URI, so replace the ";" character in the iCalendar value with
   "," and prepend the resulting string with "geo:".

4.20.  IMAGE

   Maps to a Link object with the iCalendar property value mapped to the
   location "href" property, and the "rel" property set to "icon".

   For a binary value use a base64 data uri in the "href" property.

   Mapping parameters:

   ALTREP  No mapping.

   FMTTYPE  Maps to the "contentType" property of the Link object.

   DISPLAY  Maps to the "display" property of the Link object.  The
      property values "BADGE", "GRAPHIC", "FULLSIZE" and "THUMBNAIL" map
      to their lower-case equivalent in JSCalendar.

4.21.  LOCATION

   If any [RFC9073] "VLOCATION" components are present, then the
   [RFC5545]"LOCATION" property should be ignored.

   To map the property create a "locations" property with a single
   "location" and set the "description" property to the value of the
   [RFC5545]"LOCATION" property.

   Mapping parameters:

   ALTREP  Maps to a Link object in the Location "links" property, with
      the "href" property set to the parameter value.

4.22.  METHOD

   Maps to the "method" property of the JSCalendar object.  The
   JSCalendar property value is the lowercase equivalent of the
   iCalendar property value.








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4.23.  ORGANIZER

   Maps to the "replyTo" property of the JSCalendar object.  An
   iCalendar property value in the "mailto:" URI scheme, maps to the
   "imip" method, any other value maps to the "other" method.

   If the iCalendar component also contains an ATTENDEE with the same
   calendar user address then map that ATTENDEE as defined in
   Section 4.2 and add the "owner" role to the Participant "roles"
   property.  Otherwise, use the ORGANIZER property to map to a
   Participant object.  The "roles" property of the Participant MUST
   only contain the "owner" role and the "expectReply" property value
   MUST be "false".  Any iCalendar parameters map as defined for
   ATTENDEE.

   TBD: SENT-BY parameter.  Example.

4.24.  PERCENT-COMPLETE

   For all methods other than REPLY (or no method), the PERCENT-COMPLETE
   applies to the VTODO as a whole.  In this case it the value is used
   to set the JSCalendar "percentComplete" property in the task object.

     BEGIN: VCALENDAR
     PRODID:-//ABC Corporation//NONSGML My Product//EN
     METHOD:PUBLISH
     BEGIN:VTODO
     ...
     PERCENT-COMPLETE:39
     END:VTODO
     END: VCALENDAR

     maps to

     {
       "@type": "Task",
       "prodid": "-//ABC Corporation//NONSGML My Product//EN",
       ...
       "percentComplete": 39
     }

   PERCENT-COMPLETE in a REPLY is used to indicate the level of
   completeness of the ATTENDEE.  There should only be a single ATTENDEE
   in the VTODO object.







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   As ever recurrences complicate matters.  For a non-recurring event or
   an override that contains the single participant, set the JSCalendar
   "percentComplete" property in the JSCalendar "participant" object
   representing the attendee.

     BEGIN: VCALENDAR
     PRODID:-//ABC Corporation//NONSGML My Product//EN
     METHOD:REPLY
     BEGIN:VTODO
     ...
     ATTENDEE:mailto:douglm@example.org
     PERCENT-COMPLETE:39
     END:VTODO
     END: VCALENDAR

     maps to

     {
       "@type": "Task",
       "prodid": "-//ABC Corporation//NONSGML My Product//EN",
       ...
       "participants": {
         "be450b70-9bf7-4f6e-8f65-971ede566ce3": {
           "@type": "Participant",
           "sendTo": {
             "imip": "mailto:douglm@example.org"
           },
           "percentComplete": 39,
           "roles": {
             "attendee": true
           }
         },
         ...
     }

   In the case of an override with the participant appearing in the
   master then add a patch to the override.














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     BEGIN: VCALENDAR
     PRODID:-//ABC Corporation//NONSGML My Product//EN
     METHOD:REPLY
     BEGIN:VTODO
     ...
     ATTENDEE:mailto:douglm@example.org
     END:VTODO
     BEGIN:VTODO
     ...
     RECURRENCE-ID:20200523T120000
     ...
     ATTENDEE:mailto:douglm@example.org
     PERCENT-COMPLETE:39
     END:VTODO
     END: VCALENDAR

     maps to

     {
       "@type": "Task",
       "prodid": "-//ABC Corporation//NONSGML My Product//EN",
       ...
       "participants": {
         "be450b70-9bf7-4f6e-8f65-971ede566ce3": {
           "@type": "Participant",
           "sendTo": {
             "imip": "mailto:douglm@example.org"
           },
           "roles": {
             "attendee": true
           }
         },
         "recurrenceOverrides": {
           "2020-05-23T12:00:00": {
             "participants/be4...6ce3/percentComplete": 39
           },
         ...
       }
     }

4.25.  PRIORITY

   Simply copy value into the JSCalendar "priority" property.








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4.26.  PRODID

   For a vcalendar Group object with multiple Event and/or Task object
   the [RFC5545] VCALENDAR PRODID is mapped to a JSCalendar "prodid"
   property in the group.

   When mapping to a single Event and/or Task object the [RFC5545]
   VCALENDAR PRODID is mapped to a JSCalendar "prodid" property in the
   group

     BEGIN: VCALENDAR
     PRODID:-//ABC Corporation//NONSGML My Product//EN
     BEGIN:VEVENT
     ...
     END:VEVENT
     END: VCALENDAR

     maps to

     {
       "@type": "Event",
       "prodid": "-//ABC Corporation//NONSGML My Product//EN",
       ...
     }

4.27.  RECURRENCE-ID

   Refer to Section 6 for information on mapping recurrence ids.

4.28.  RELATED-TO

   This is mapped to the JSCalendar "relatedTo" property which is a map
   of relations with the target UID as the keys.  The iCalendar relation
   is by default a PARENT relationship.  There is no default for
   JSCalendar so the relationship must be explicitly specified.

   The RELTYPE parameter values map to their lowercase equivalents in
   the "relation" property.

   Also note that the iCalendar relationship types are not identical.
   CHILD and PARENT map to JSCalendar "child" and "parent" but the best
   match for iCalendar SIBLING is "next"









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     ...
     RELATED-TO:jsmith.part7.19960817T083000.xyzMail@example.com
     RELATED-TO;RELTYPE=SIBLING:
      19960401-080045-4000F192713-0052@example.com
     ...

     maps to

     "relatedTo" : {
       "jsmith.part7.19960817T083000.xyzMail@example.com" : {
         "@type" : "Relation",
         "relation" : {
           "parent" : true
         }
       },
       "19960401-080045-4000F192713-0052@example.com" : {
         "@type" : "Relation",
         "relation" : {
           "next" : true
         }
       },
     },
     {
       "@type": "Event",
       "prodid": "-//ABC Corporation//NONSGML My Product//EN",
       ...
     }

4.29.  REQUEST-STATUS

   Copy the value into the JSCalendar "requestStatus" property.

4.30.  RESOURCES

   The RESOURCES property value is a comma-separated list of resources.
   First split this into the separate resource names and then each
   resource is mapped on a participant object with a "kind" property of
   "resource" and the "name" property set to the resource name.

   Mapping parameters:

   ALTREP  Use the same process as for the ATTENDEE DIR parameter:
      create a link property with the "rel" property set to "alternate"
      and the "href" property set to the value of the ALTREP parameter.
      Then add the link to the participants "links" property.

   LANG  Set the participants "language" property.




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   For an example see Section 7.3

4.31.  RDATE

   If the RDATE has a RANGE=THISANDFUTURE parameter then the recurrence
   MUST be split at this RDATE.

   Truncate the original object before this RDATE, create a new master
   representing the object and link them by setting the jscalendar
   "relatedTo" property in both.

   Otherwise create a patch object with the recurrence id set from the
   RDATE value.  If the instance has overrides the differences will also
   be set in the object.

4.32.  RRULE

   Each RRULE is converted to an object in the JSCalendar
   "recurrenceRules" property.  Each entry has the type
   "RecurrenceRule".

     ...
     RRULE:...
     ...

     maps to

     ...
     "recurrenceRules" : [{
         "@type" : "RecurrenceRule",
         ...
       }],
       ...

   The recurrence rule object has one property for each element of the
   recurrence rule.  The iCalendar rule has to be parsed out and the
   individual jscalendar property values set.  Most take the same type
   but there are exceptions.

   FREQ (mandatory)  Copy into the jscalendar "frequency" property
      converted to lowercase.

   INTERVAL  If present and not 1 copy into the jscalendar "interval"
      property.

   RSCALE  If present copy into the jscalendar "rscale" property
      converted to lowercase.




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   SKIP  If present copy into the jscalendar "skip" property converted
      to lowercase.

   WKST  If present copy into the jscalendar "firstDayOfWeek" property
      converted to lowercase.

   BYDAY  If present each element becomes an entry in the jsCalendar
      "byDay" propety.  This is an array of NDay objects which may have
      2 properties:

      day  The two character weekday abbreviation.

      nthOfPeriod  If the weekday abbreviation is preceded by a signed
         integer value set the jscalendar "nthOfPeriod" property.

        ...
        RRULE:...,BYDAY=-1MO
        ...

        maps to

        ...
        "recurrenceRules" : [{
            "@type" : "RecurrenceRule",
            ...
            "byday": [{
                "day": "mo",
                "nthOfPeriod": -1
              }]
            ...
          }],
          ...

   BYMONTHDAY  If present each element will be an element in the
      jscalendar "byMonthDay" property.

   BYMONTH  If present each element will be an element in the jscalendar
      "byMonth" property.

      Note that the iCalendar values are numeric but the JSCalendar
      values are strings.  This is because of the possible "L" suffix
      for leap months.

   BYYEARDAY  If present each element will be an element in the
      jscalendar "byYearDay" property.

   BYWEEKNO  If present each element will be an element in the
      jscalendar "byWeekNo" property.



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   BYHOUR  If present each element will be an element in the jscalendar
      "byHour" property.

   BYMINUTE  If present each element will be an element in the
      jscalendar "byMinute" property.

   BYSECOND  If present each element will be an element in the
      jscalendar "bySecond" property.

   BYSETPOS  If present each element will be an element in the
      jscalendar "bySetPosition" property.

   COUNT  If present set in the jscalendar "count" property.

   UNTIL  If present set the jscalendar "until" property with the
      appropriately reformatted value.  If the is no time part append a
      0 time and reformat as a jscalendar local date/time.

   Some examples:

     ...
     RRULE:FREQ=DAILY;COUNT=10
     ...

     maps to

     ...
     "recurrenceRules" : [{
         "@type" : "RecurrenceRule",
         "frequency": "daily",
         "count": 10
       }],
       ...


















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     ...
     RRULE:FREQ=YEARLY;UNTIL=20220512T140000Z;
      BYMONTH=1;BYDAY=SU,MO,TU,WE,TH,FR,SA
     ...

     maps to

     ...
     "recurrenceRules" : [{
         "@type" : "RecurrenceRule",
         "frequency": "yearly",
         "byMonth": ["1"],
         "byDay": [{
               "day": "su"
             },
             }
               "day": "mo"
             },
             }
               "day": "tu"
             },
             }
               "day": "we"
             },
             }
               "day": "th"
             },
             }
               "day": "fr"
             },
             }
               "day": "sa"
             }],
         "until": "2022-05-12T10:00:00"
       }],
       ...















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     ...
     RRULE:FREQ=MONTHLY;COUNT=6;BYDAY=-2MO
     ...

     maps to

     ...
     "recurrenceRules" : [{
         "@type" : "RecurrenceRule",
         "frequency": "monthly",
         "byDay": [{
             "day": "mo",
             "nthOfPeriod": -2
           }],
         "count": 6
       }],
       ...

4.33.  SEQUENCE

   Copy the value into the JSCalendar "sequence" property.

4.34.  STATUS

   For a VEVENT copy the lower-cased value into the JSCalendar "status"
   property.

   For a VTODO copy the lower-cased value into the JSCalendar "progress"
   property.

4.35.  STRUCTURED-DATA

   This property is mapped on to a JSCalendar "link" object with the
   value mapped on to the JSCalendar "href" property in a manner
   depending on the "STRUCTURED-DATA" "VALUE" parameter:

   VALUE=TEXT  Copy the value as a [RFC2397] data uri either as plain
      text or by encoding as a base64 value.  If plain text the value
      may need escaping as per [RFC2397].

   VALUE=BINARY  Copy the value as a [RFC2397] data uri speifying base64
      encoding.

   VALUE=URI  Copy the value as-is into the href.

   The "STRUCTURED-DATA" "SCHEMA" parameter is mapped on to a JSCalendar
   "schema" property within the link object.




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   The "STRUCTURED-DATA" "FMTTYPE" parameter is mapped on to a
   JSCalendar "contentType" property within the link object.

   For example:

     ...
     STRUCTURED-DATA;FMTTYPE=application/ld+json;
         SCHEMA="https://schema.org/SportsEvent";
         VALUE=TEXT:{\n
           "@context": "http://schema.org"\,\n
           "@type": "SportsEvent"\,\n
           "homeTeam": "Pittsburgh Pirates"\,\n
           "awayTeam": "San Francisco Giants"\n
         }\n
     ...

     maps to (with data truncated)

     ...
     "links": {
       "1": {
         "@type" : "Link",
         "contentType": "application/ld+json",
         "schema": "https://schema.org/SportsEvent",
         "href": "data:base64;ewogICAgICAgICJAY29udGV4dCI6IC..."
       }
     }
     ...

4.36.  SUMMARY

   Copy the value into the JSCalendar "title" property.

   Mapping parameters:

   ALTREP  No mapping.

   LANG  Use the "locale" property.

4.37.  TRANSP

   If the value of the TRANSP property (ignoring case) is "opaque" set
   the JSCalendar "freeBusyStatus" property to the value "busy".

   Otherwise set the JSCalendar "freeBusyStatus" property to the value
   "free".





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4.38.  UID

   Copy the value into the JSCalendar "uid" property.

4.39.  URL

   Maps to a Link object in the JSCalendar object's "links" property,
   with the URL property value mapped to the Link "href" property.

5.  Translating non-standard iCalendar to JSCalendar

   iCalendar data may contain entries for which no standard property or
   object type exists in JSCalendar.  This mainly occurs for
   experimental properties, parameter and components in iCalendar (_X_-
   extensions, see Section 3.8.8.2 of [RFC5545]), but may be the case
   for other iCalendar data, too.  Typically, the semantics or value
   types of such entries are known.

   This section defines new properties, by which implementations SHOULD
   map such data.  Applications that have more insight into the
   semantics of such iCalendar entries MAY choose to map differently.

   NOTE: The verbatim XXXX values in this section will be replaced with
   the RFC number of this document before publication.  Also, the
   following properties require a redefinition of vendor-extension
   properties for JSCalendar.  Currently, only domain names are allowed
   as prefix for vendor extensions.  This document assumes that also
   URIs with the urn scheme are allowed.

5.1.  urn:ietf:rfcXXXX#components

   Type: JCalComp[] where JCalComp denotes a jCal-encoded component as
   defined in Section 3.3 of [RFC7265]

   This property is set on a JSCalendar object for which a standard
   mapping from an iCalendar component is defined.  If set, it contains
   one or more iCalendar components that are direct children of the
   iCalendar component represented by the JSCalendar object.













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   BEGIN:VEVENT
   UID:c2236fe3-4dc9-4b3b-8a18-cd8f29eca594
   DTSTART:20220711T104800
   BEGIN:X-COMP
   UID:6dcff59c-d251-44c9-9010-a62cab390df0
   END:X-COMP
   END:VEVENT

   maps to

   {
     "@type": "Event",
     "uid": "c2236fe3-4dc9-4b3b-8a18-cd8f29eca594",
     "start": "2022-07-11T10:48:00",
     "urn:ietf:rfcXXXX#components": [
       ["x-comp", [
         ["uid", {}, "text", "6dcff59c-d251-44c9-9010-a62cab390df0"]
       ]
     ]
   }

5.2.  urn:ietf:rfcXXXX#properties

   Type: JCalProp[] where JCalProp denotes a jCal-encoded property as
   defined in Section 3.4 of [RFC7265]

   This property is set on a JSCalendar object for which a standard
   mapping from an iCalendar component is defined.  If set, it contains
   one or more iCalendar properties that are set in the iCalendar
   component represented by the JSCalendar object.





















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   BEGIN:VEVENT
   UID:c2236fe3-4dc9-4b3b-8a18-cd8f29eca594
   DTSTART:20220711T104800
   X-PROP;X-PARAM=Bar:Foo
   END:VEVENT

   maps to

   {
     "@type": "Event",
     "uid": "c2236fe3-4dc9-4b3b-8a18-cd8f29eca594",
     "start": "2022-07-11T10:48:00",
     "urn:ietf:rfcXXXX#properties": [
       ["x-prop", {
         "x-param": "Bar"
       }, "unknown", "Foo"]
     ]
   }

5.3.  urn:ietf:rfcXXXX#parameters

   Type: String[String] denotes a JSON object encoding iCalendar
   parameters as defined in Section 3.5 of [RFC7265]

   This property is set on a JSCalendar object for which a standard
   mapping from an iCalendar property is defined.  If set, it contains
   one or more iCalendar parameters that are set on the iCalendar
   property represented by the JSCalendar object.

   ...
   ATTACH;X-PARAM=Bar;VALUE=URI:https://example.com/foo.zip
   ...

   maps to

   ...
   {
     "@type": "Link",
     "href": "https://example.com/foo.zip",
     "urn:ietf:rfcXXXX#parameters": {
       "x-param": "Bar"
     }
   }
   ...







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5.4.  urn:ietf:rfcXXXX#prop

   A short-form variant of the properties property defined in
   Section 5.2 MAY be used to map a single property from iCalendar.
   This aims to provide a compact representation for mapping an
   iCalendar property without parameters and for which no value type is
   known.  It is defined as follows:

   Name: urn:ietf:rfcXXXX#prop/_propname_ where _propname_ denotes the
   ASCII lower-case name (Section 3.1 of [RFC5545]) of the mapped
   property.

   Type: String where the string must adhere to the definitions of
   Section 5 of [RFC7265].

   The following example contains both the long-form and short-form
   mapping for illustration:

   ...
   X-Foo:Bar
   ...

   maps to short-form

   ...
   "urn:ietf:rfcXXXX#prop/x-foo": "Bar"
   ...

   or long-form

   ...
   "urn:ietf:rfcXXXX#properties": [
       ["x-foo", { }, "unknown", "Bar"]
   ]
   ...

6.  Translating iCalendar Recurrences

6.1.  Translating iCalendar Recurrences: Simple objects with overrides

   A simple object with overrides will be converted to a jsCalendar
   master event with the rules, recurrence dates and exclusion dates
   translated appropriately.

   Overrides MUST be mapped on to a jsCalendar patch object and added to
   the "recurrenceOverrides" property of the master event with the key
   being the value of the iCalendar RECURRENCE-ID translated to a json
   format.



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   Any override property with the same value as the master SHOULD be
   ommitted.  Remaining properties MAY be added in full.  Where
   appropriate, differences SHOULD be expressed as a patch.

   This can result in a significant reduction in size for objects with
   small changes to overrides, for example changing the participation
   status of an attendee.

6.2.  Translating iCalendar Recurrences: Overrides with no master

   When inviting an attendee to a single instance of a recurring event,
   only that override should be sent to the attendee.  In this case the
   override should be a complete jsCalendar object with the type set to
   the type of the master.

   Additionally, there MUST be a recurrenceId property set to the value
   of the recurrence id for that override.  If the timezone of the start
   of the instance is different from the master value, then there must
   also be a "recurrenceIdTimeZone" property set to the start timezone
   of the master.

7.  Translating iCalendar: Further examples

   This section provides more complete examples of translating from
   [RFC5545] to JSCalendar.

   As usual note that json string values may be split because of line
   width limits.  This is not legal json.

7.1.  Recurring event with ATTACH

   This is an example of a recurring event with overrides.  The first
   override removes an ATTACH property and adds an ATTACH property.  The
   second override removes all ATTACH properties.

     BEGIN:VCALENDAR
     CALSCALE:GREGORIAN
     PRODID:-//example.org//EN
     VERSION:2.0
     BEGIN:VEVENT
     DTSTAMP:20200522T142047Z
     DTSTART;TZID=America/New_York:20200522T120000
     DURATION:PT1H
     RRULE:FREQ=DAILY;COUNT=8
     SUMMARY:recurring daily 8 times
     UID:6252D6C40A8308BFE25BBDErecur-1
     ATTACH;FMTTYPE=text/plain:http://example.org/doc1.txt
     ATTACH;FMTTYPE=text/plain:http://example.org/doc2.txt



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     ATTACH;FMTTYPE=text/plain:http://example.org/doc3.txt
     END:VEVENT
     BEGIN:VEVENT
     DTSTAMP:20200522T142047Z
     DTSTART;TZID=America/New_York:20200523T120000
     DURATION:PT1H
     RECURRENCE-ID;TZID=America/New_York:20200523T120000
     SUMMARY:recurring daily 8 times
     UID:6252D6C40A8308BFE25BBDErecur-1
     ATTACH;FMTTYPE=text/plain:http://example.org/doc2.txt
     ATTACH;FMTTYPE=text/plain:http://example.org/doc3.txt
     ATTACH;FMTTYPE=text/plain:http://example.org/doc4.txt
     END:VEVENT
     BEGIN:VEVENT
     DTSTAMP:20200522T142047Z
     DTSTART;TZID=America/New_York:20200524T120000
     DURATION:PT1H
     RECURRENCE-ID;TZID=America/New_York:20200524T120000
     SUMMARY:recurring daily 8 times
     UID:6252D6C40A8308BFE25BBDErecur-1
     END:VEVENT
     END:VCALENDAR

     maps to

     {
       "prodId": "//example.org//EN",
       "entries": [
         {
           "links": {
             "1": {
               "@type": "Link",
               "rel": "enclosure",
               "contentType": "text/plain",
               "href": "http://example.org/doc1.txt"
             },
             "2": {
               "@type": "Link",
               "rel": "enclosure",
               "contentType": "text/plain",
               "href": "http://example.org/doc2.txt"
             },
             "3": {
               "@type": "Link",
               "rel": "enclosure",
               "contentType": "text/plain",
               "href": "http://example.org/doc3.txt"
             }



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           },
           "created ": "2020-05-23T17:04:50Z",
           "start": "2020-05-22T12:00:00",
           "timeZone": "America/New_York",
           "duration": "PT1H",
           "title": "recurring daily 8 times",
           "uid": "6252D6C40A8308BFE25BBDErecur-1",
           "recurrenceRules": [
             {
               "@type": "RecurrenceRule",
               "frequency": "daily",
               "count": 8
             }
           ],
           "recurrenceOverrides": {
             "2020-05-23T12:00:00": {
               "recurrenceId": "2020-05-23T12:00:00",
               "links/d4a618d4-929c-4c81-ae5b-322afe407a00": null,
               "links/fb75b76a-a159-4a86-bd3d-7ace6b39c6c3": {
                 "@type": "Link",
                 "rel": "enclosure",
                 "contentType": "text/plain",
                 "href": "http://example.org/doc4.txt"
               }
             },
             "2020-05-24T12:00:00": {
               "recurrenceId": "2020-05-24T12:00:00",
               "links/d4a618d4-929c-4c81-ae5b-322afe407a00": null,
               "links/6c54e72e-3413-487c-ae14-fb318a90db43": null,
               "links/44087e9a-132c-4a5d-b25d-4ce580edb004": null
             }
           }
         }
       ]
     }

7.2.  Simple event with CONTACT

   This example shows the conversion of a simple event with a single
   CONTACT property in JSCalendar.

     BEGIN:VCALENDAR
     CALSCALE:GREGORIAN
     PRODID:-//Example//EN
     VERSION:2.0
     BEGIN:VEVENT
     DTSTAMP:20200522T142047Z
     DTSTART;TZID=America/New_York:20200622T120000



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     DURATION:PT1H
     SUMMARY:event with contact
     UID:6252D6C40A8308BFE25BBEFcontact-1
     CONTACT;ALTREP="ldap://example.com:6666/o=ABC%20Industries\,
      c=US???(cn=Jim%20Dolittle)":Jim Dolittle\, ABC Industries\,
      +1-919-555-XXXX
     END:VEVENT
     END:VCALENDAR

     translates to

     {
       "@type": "Group",
       "prodId": "//Example.org//Example V3.13.2//EN",
       "entries": [
         {
           "@type": "Event",
           "participants": {
             "40288108-733187c1-0173-3188007b-00000001": {
               "@type": "Participant",
               "roles": {
                 "contact": true
               },
               "description": "Jim Dolittle, ABC Industries,\
                              +1-919-555-XXXX",
               "links": {
                 "1": {
                   "@type": "Link",
                   "href": "ldap://example.com:6666/o=ABC%20Industries,\
                                  c=US???(cn=Jim%20Dolittle)",
                   "rel": "alternate"
                 }
               }
             }
           },
           "created ": "2020-07-09T03:04:23Z",
           "start": "2020-06-22T12:00:00",
           "timeZone": "America/New_York",
           "duration": "PT1H",
           "title": "event with contact",
           "uid": "6252D6C40A8308BFE25BBEFcontact-1"
         }
       ]
     }







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7.3.  Simple event with RESOURCES

   TBD

7.4.  Recurring event.  Attendees only in overrides

   In this more complex example there is no ORGANIZER or ATTENDEEs in
   the master event.  There are overrides which invite one or more
   attendees.

   For one overrride the ORGANIZER is also an ATTENDEE.  In the other
   that is not the case.  This is reflected in the "roles" property for
   the organizer.

   Note that each override has its own "participants" property and the
   first has a links property to handle the DIR parameter on one
   attendee.

       BEGIN:VCALENDAR
       PRODID://Example.org//Example V3.13.2//EN
       VERSION:2.0
       BEGIN:VEVENT
       CREATED:20200704T035515Z
       DURATION:PT1H
       DTSTAMP:20200704T035706Z
       DTSTART;TZID=America/New_York:20200522T120000
       LAST-MODIFIED:20200704T035706Z
       SUMMARY:recurring daily 8 times
       UID:6252D6C40A8308BFE25BBEFrecur1-1
       RRULE:FREQ=DAILY;COUNT=8
       END:VEVENT
       BEGIN:VEVENT
       RECURRENCE-ID;TZID=America/New_York:20200523T120000
       ATTENDEE:mailto:douglm@example.org
       ATTENDEE;RSVP=TRUE;SCHEDULE-STATUS=1.2;DIR="http://example.org/
        vcards/vbede.vcf":mailto:vbede@example.org
       CREATED:20200704T035515Z
       DURATION:PT1H
       DTSTAMP:20200704T035706Z
       DTSTART;TZID=America/New_York:20200523T120000
       LAST-MODIFIED:20200704T035706Z
       ORGANIZER:mailto:douglm@example.org
       SUMMARY:recurring daily 8 times
       UID:6252D6C40A8308BFE25BBEFrecur1-1
       END:VEVENT
       BEGIN:VEVENT
       RECURRENCE-ID;TZID=America/New_York:20200524T120000
       ATTENDEE;RSVP=TRUE;SCHEDULE-STATUS=1.2:mailto:user01@example.org



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       ATTENDEE;RSVP=TRUE;SCHEDULE-STATUS=1.2:mailto:vbede@example.org
       CREATED:20200704T035515Z
       DURATION:PT1H
       DTSTAMP:20200704T035706Z
       DTSTART;TZID=America/New_York:20200524T120000
       LAST-MODIFIED:20200704T035706Z
       ORGANIZER:mailto:douglm@example.org
       SUMMARY:recurring daily 8 times
       UID:6252D6C40A8308BFE25BBEFrecur1-1
       END:VEVENT
       END:VCALENDAR

       translates to

       {
         "@type": "Group",
         "prodId": "//Example.org//Example V3.13.2//EN",
         "entries": [
           {
             "@type": "Event",
             "created ": "2020-07-04T03:57:06Z",
             "start": "2020-05-22T12:00:00",
             "timeZone": "America/New_York",
             "duration": "PT1H",
             "title": "recurring daily 8 times",
             "uid": "6252D6C40A8308BFE25BBEFrecur1-1",
             "recurrenceRules": [
               {
                 "@type": "RecurrenceRule",
                 "frequency": "daily",
                 "count": 8
               }
             ],
             "recurrenceOverrides": {
               "2020-05-23T12:00:00": {
                 "participants": {
                   "be450b70-9bf7-4f6e-8f65-971ede566ce3": {
                     "@type": "Participant",
                     "sendTo": {
                       "imip": "mailto:douglm@example.org"
                     },
                     "roles": {
                       "attendee": true,
                       "owner": true
                     }
                   },
                   "a539dfe3-4463-4f28-b9de-17d3a0e99faf": {
                     "@type": "Participant",



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                     "sendTo": {
                       "imip": "mailto:vbede@example.org"
                     },
                     "expectReply": true,
                     "links": {
                       "1": {
                         "@type": "Link",
                         "href": "http://example.org/vcards/vbede.vcf",
                         "rel": "alternate"
                       }
                     },
                     "roles": {
                       "attendee": true
                     },
                     "scheduleStatus": "1.2"
                   }
                 },
                 "replyTo": {
                   "imip": "mailto:douglm@example.org"
                 }
               },
               "2020-05-24T12:00:00": {
                 "participants": {
                   "daeae4cf-6f6a-4ce3-9f4d-6bd884650d3d": {
                     "@type": "Participant",
                     "sendTo": {
                       "imip": "mailto:user01@example.org"
                     },
                     "expectReply": true,
                     "roles": {
                       "attendee": true
                     },
                     "scheduleStatus": "1.2"
                   },
                   "a6de6de3-271f-4679-9241-1b3bca6b602d": {
                     "@type": "Participant",
                     "sendTo": {
                       "imip": "mailto:vbede@example.org"
                     },
                     "expectReply": true,
                     "roles": {
                       "attendee": true
                     },
                     "scheduleStatus": "1.2"
                   },
                   "aaa8483b-b18b-4dbd-b218-77d8db027d35": {
                     "@type": "Participant",
                     "sendTo": {



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                       "imip": "mailto:douglm@example.org"
                     },
                     "roles": {
                       "owner": true
                     }
                   }
                 },
                 "replyTo": {
                   "imip": "mailto:douglm@example.org"
                 }
               }
             }
           }
         ]
       }

8.  Translating JSCalendar objects to iCalendar

   This section lists the JSCalendar objects that map to [RFC5545]
   components.

8.1.  Event

   A JSCalendar object with a type of "Event" is mapped on to a
   [RFC5545] VEVENT component.

   If it is a single VEVENT then a [RFC5545] VCALENDAR component must
   surround it and the JSCalendar "prodid" property will be converted to
   a [RFC5545] PRODID.

     {
       "@type": "Event",
       "prodid": "-//ABC Corporation//NONSGML My Product//EN",
       ...
     }

     maps to

     BEGIN: VCALENDAR
     PRODID:-//ABC Corporation//NONSGML My Product//EN
     BEGIN:VEVENT
     ...
     END:VEVENT
     END: VCALENDAR

   When converting multiple Event or Task objects the surrounding
   [RFC5545] VCALENDAR object must have a [RFC5545] PRODID set from
   either the Group "prodid" or generated.



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8.2.  Group

   A JSCalendar object with a type of "Group" is mapped on to a
   [RFC5545] VCALENDAR component.

     {
       "@type": "Group",
       "prodid": "-//ABC Corporation//NONSGML My Product//EN",
       ...
       {
         "@type": "Event",
         ...
       }
       {
         "@type": "Event",
         ...
       }
     }

     maps to

     BEGIN: VCALENDAR
     PRODID:-//ABC Corporation//NONSGML My Product//EN
     BEGIN:VEVENT
     ...
     END:VEVENT
     BEGIN:VEVENT
     ...
     END:VEVENT
     END: VCALENDAR

8.3.  Task

   A JSCalendar object with a type of "Task" is mapped on to a [RFC5545]
   VTODO component.

   If it is a single VTODO then a [RFC5545] VCALENDAR component must
   surround it and the JSCalendar "prodid" property will be converted to
   a [RFC5545] PRODID.












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     {
       "@type": "Task",
       "prodid": "-//ABC Corporation//NONSGML My Product//EN",
       ...
     }

     maps to

     BEGIN: VCALENDAR
     PRODID:-//ABC Corporation//NONSGML My Product//EN
     BEGIN:VTODO
     ...
     END:VTODO
     END: VCALENDAR

   When converting multiple Event or Task objects the surrounding
   [RFC5545] VCALENDAR object must have a [RFC5545] PRODID set from
   either the Group "prodid" or generated.

9.  Translating JSCalendar properties to iCalendar

   This section is an alphabetic list of all JSCalendar top-level
   properties that map to [RFC5545] iCalendar.

9.1.  alerts

   Each member of a JSCalendar alerts property maps to a [RFC5545]
   VALARM component.  Only display and email alarms are allowed in
   JSCalendar.

9.1.1.  action

   The JSCalendar "action" property maps to the [RFC5545] ACTION
   property.  The value SHOULD be the uppercased version of the
   JSCalendar "alert" property.

   For example:














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      ...
      "action": "display",
      ...

     maps to

      ACTION:DISPLAY

     and

      ...
      "action": "email",
      ...

     maps to

      ACTION:EMAIL

9.1.2.  title and description

   The iCalendar DESCRIPTION property is required for both ACTION:EMAIL
   and ACTION:DISPLAY.  Additionally, the iCalendar SUMMARY property is
   required for ACTION:EMAIL.

   Both of these are optional in a JSCalendar alert.  When converting is
   there is a title property in the alert use that for the SUMMARY.

   Similarly if a JSCalendar description property is present use that
   for the description.  Otherwise use the alert title property and if
   that is absent use the event title.

9.1.3.  trigger

   A JSCalendar trigger with a type of "AbsoluteTrigger" maps on to a
   [RFC5545] TRIGGER property with a "VALUE" parameter of "DATE-TIME"
   and a value taken from the JSCalendar "when" property.

   For example:

      "trigger": {
        "@type": "AbsoluteTrigger",
        "when": "20210315T133000Z"
      }

     maps to

      TRIGGER;VALUE=DATE-TIME:20210315T133000Z




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   A JSCalendar trigger with a type of "OffsetTrigger" maps on to a
   [RFC5545] TRIGGER property with a duration value taken from the
   JSCalendar "offset" property.

   If the JSCalendar trigger has a "relativeTo" property with the value
   "end" then the [RFC5545] TRIGGER property will have a RELATED=END
   parameter.

   For example:

      "trigger": {
        "@type": "OffsetTrigger",
        "offset": "-P2D",
        "relativeTo": "end"
      }

     maps to

      TRIGGER;RELATED=END:-P2D

     and

        "trigger": {
        "@type": "OffsetTrigger",
        "offset": "-PT30M"
      }

     maps to

     TRIGGER:-PT30M

9.1.4.  todo

   Need to deal with "acknowledged" and "relatedTo".  Also in the
   icalendar to jscalendar.

9.1.5.  Example event with alerts

     {
       "@type": "Group",
       "prodId": "//Example.org//Example V3.14//EN",
       "entries": [
         {
           "@type": "Event",
           "alerts": {
             "1": {
               "@type": "Alert",
               "action": "display",



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               "trigger": {
                 "@type": "AbsoluteTrigger",
                 "when": "2022-05-08T12:00:00Z"
               }
             },
             "2": {
               "@type": "Alert",
               "action": "display",
               "description": "Breakfast meeting with executive\nteam
                               at 8:30 AM EST.",
               "trigger": {
                 "@type": "OffsetTrigger",
                 "offset": "-PT30M"
               }
             },
             "3": {
               "@type": "Alert",
               "action": "email",
               "title": "*** REMINDER: SEND AGENDA FOR WEEKLY
                         STAFF MEETING ***",
               "description": "A draft agenda needs to be sent out to
                         the attendees to the weekly managers meeting
                         (MGR-LIST). Attached is a pointer the document
                         template for the agenda file.",
               "trigger": {
                 "@type": "OffsetTrigger",
                 "offset": "-P-2D",
                 "relativeTo": "end"
               }
             }
           },
           "created": "2022-05-02T20:04:12Z",
           "start": "2022-06-22T12:00:00",
           "timeZone": "America/New_York",
           "duration": "PT1H",
           "title": "event with alarms",
           "uid": "6252D6C40A8308BFE25BBEFsimple-alarms-1"
         }
       ]
     }
     maps to

     BEGIN:VEVENT
     CREATED:20220502T200412Z
     DURATION:PT1H
     DTSTAMP:20220502T201921Z
     DTSTART;TZID=America/New_York:20220622T120000
     LAST-MODIFIED:20220502T201921Z



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     SUMMARY:event with alarms
     UID:6252D6C40A8308BFE25BBEFsimple-alarms-1
     BEGIN:VALARM
     ACTION:DISPLAY
     TRIGGER;RELATED=START:-PT30M
     DESCRIPTION:event with alarms
     END:VALARM
     BEGIN:VALARM
     ACTION:DISPLAY
     TRIGGER;VALUE=DATE-TIME:20220508T120000Z
     DESCRIPTION:event with alarms
     END:VALARM
     BEGIN:VALARM
     ACTION:EMAIL
     TRIGGER;RELATED=END:-P2D
     DESCRIPTION:A draft agenda needs to be sent out to the attendees
       to the weekly managers meeting (MGR-LIST). Attached is a pointe
      r the document template for the agenda file.
     SUMMARY:*** REMINDER: SEND AGENDA FOR WEEKLY STAFF MEETING ***
     END:VALARM
     END:VEVENT

9.2.  categories

   Each member of the JSCalendar "categories" property maps on to a
   [RFC9073] CONCEPT property with the value being the key of each
   member.

   For example:

      ...
      "categories": {
        "http://example.com/event-types/arts/music": true,
        "http://example.com/performance-types/arts/live": true
      }
      ...

     maps to

      ...
      CONCEPT:http://example.com/event-types/arts/music
      CONCEPT:http://example.com/performance-types/arts/live
      ...

9.3.  color

   The value is copied verbatim to the [RFC7986] "COLOR" property.




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9.4.  created

   The JSCalendar "created" property maps on to a [RFC5545] CREATED
   property with the value being the [RFC5545] UTC date-time derived
   from the value of the property.

   For example:

      ...
      "created": "2021-03-15T13:30"00Z"
      ...

     maps to

      ...
      CREATED:20210315T133000Z
      ...

9.5.  duration

   The JSCalendar "duration" property is only valid for event objects.
   Copy the JSCalendar "duration" property in to the [RFC5545] DURATION
   property.

   For example:

      ...
      "duration": "PT1H"
      ...

     maps to

      ...
      DURATION:PT1H
      ...

9.6.  estimatedDuration

   The JSCalendar "estimatedDuration" property is only valid for task
   objects.  Copy the JSCalendar "estimatedDuration" property in to the
   [RFC5545] ESTIMATED-DURATION property.

   For example:








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      ...
      "estimatedDuration": "PT18H"
      ...

     maps to

      ...
      ESTIMATED-DURATION:PT18H
      ...

9.7.  keywords

   Each member of the JSCalendar "keywords" property maps on to a
   [RFC5545] CATEGORIES property with the value being the key of each
   member.

   For example:

      ...
      "keywords": {
           "APPOINTMENT": true,
           "EDUCATION": true,
           "MEETING": true
         },
      ...

     maps to

      ...
      CATEGORIES:APPOINTMENT
      CATEGORIES:EDUCATION
      CATEGORIES:MEETING
      ...

      or alternatively

      ...
      CATEGORIES:APPOINTMENT,EDUCATION,MEETING
      ...

9.8.  locations

   JSCalendar locations map to [RFC9073] VLOCATION components.

   Additionally, for backwards compatibility, one location should be
   mapped on to a [RFC5545] LOCATION property.





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9.8.1.  coordinates

   TODO.  Need to decide if to use GEO or define new GEO-URI.

9.8.2.  description

   The "description" property maps to the DESCRIPTON property value of
   the VLOCATION.

9.8.3.  links

   TODO.  First need to define top-level links property mapping.

9.8.4.  locationTypes

   The keys of the "locationTypes" property map to the LOCATION-TYPE
   property value of the VLOCATION.  The keys MUST be separated by the
   COMMA character (U+002c) and SHOULD sort in ascending alphabetical
   order.

9.8.5.  name

   The "name" property maps to the NAME property value of the VLOCATION.

9.8.6.  relativeTo

   The "relativeTo" property maps to the RELATED-TO property value of
   the VLOCATION.  TODO need updated definition of the RELATED-TO draft.

9.8.7.  timeZone

   The "timeZone" property maps to the TZID property value of the
   VLOCATION.

   If the TimeZoneId value matches a name from the IANA Time Zone
   Database [TZDB] then this value MUST be set in the TZID property.

   If the TimeZoneId identifies a custom TimeZone in the JSCalendar
   object, then the TZID property value MUST be set to the "tzId"
   property value of the custom TimeZone object, and its related
   VTIMEZONE added to the VCALENDAR component that encloses the
   VLOCATION.









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9.8.8.  uid

   The "uid" property maps to the UID property value of the VLOCATION.
   The identifier of the Location object in the enclosing "locations"
   property maps to the JMAP-ID property parameter.  The parameter MAY
   be omitted if the identifier of the Location matches the "uid" value.

9.9.  participants

   JSCalendar participants will be mapped on to different iCalendar
   properties and components depending on their jsCalendar role values.

   A participant with a role containing "contact" MUST be mapped on to
   an iCalendar CONTACT property and SHOULD also be mapped on to a
   [RFC9073]PARTICIPANT component which provides a better mapping.

   A participant with a role containing "owner" MUST be mapped on to an
   iCalendar ORGANIZER property and SHOULD also be mapped on to a
   [RFC9073]PARTICIPANT component which provides a better mapping.

   A participant with a role containing any of "attendee", "optional" or
   "informational" MUST be mapped on to an iCalendar ATTENDEE property
   and SHOULD also be mapped on to a [RFC9073]PARTICIPANT component
   which provides a better mapping.

   A more complete mapping may be achieved by creating a
   [RFC9073]PARTICIPANT component.

   For all properties the participants jsCalendar "language" property,
   if present, is mapped on to the iCalendar "LANG" property parameter.

   For all properties if the participant contains a jsCalendar "link"
   with a "rel" of "alternate" then the value of the link is used for
   the iCalendar "ALTREP" property parameter.

   Where do we get the cua?

9.10.  timezones

   The JSCalendar TimeZone objects within a "timezones" property are
   mapped on to [RFC5545] VTIMEZONE components within the surrounding
   VCALENDAR component.  Each mapped TimeZone MUST only appear once.









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     {
       "@type": "Event",
       ...
       "timezones": {
         "/Example/Somewhere: {
           "@type": "TimeZone",
           "tzId": "Example/Somewhere",
           ...
         },
         "/Example/Somewhere-else": {
           "@type": "TimeZone",
           "tzId": "Example/Somewhere-else",
           ...
         }
       }
     }

     maps to

     BEGIN: VTIMEZONE
     TZID: Example/Somewhere
     ...
     END: VTIMEZONE
     BEGIN: VTIMEZONE
     TZID: Example/Somewhere-else
     ...
     END: VTIMEZONE
     BEGIN: VEVENT
     ...
     END: VEVENT

   When converting multiple Event or Task objects the surrounding
   [RFC5545] VCALENDAR object must have a [RFC5545] PRODID set from
   either the Group "prodid" or generated.

10.  Translating non-standard JSCalendar to iCalendar

   JSCalendar objects may contain properties for which no standard
   mapping to iCalendar is defined.  This may occur for vendor-extension
   properties (Section 3.3 of [draft-ietf-calext-jscalendarbis]) or any
   other property for which there no standard mapping is defined.

   This section defines properties and parameters with which
   implementations SHOULD map such data.  Applications that have more
   insight into the semantics of such iCalendar entries MAY choose to
   map differently.





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   NOTE: The verbatim XXXX values in this section will be replaced with
   the RFC number of this document before publication.  Also, the
   following properties require a redefinition of vendor-extension
   properties for JSCalendar.  Currently, only domain names are allowed
   as prefix for vendor extensions.  This document assumes that also
   URIs with the urn scheme are allowed.

10.1.  New iCalendar properties

10.1.1.  X-RFCXXXX-JSPROP Property

   Property name:  X-RFCXXXX-JSPROP

   Purpose:  This property embeds JSCalendar properties in iCalendar.

   Value type:  URI, also see Format Definition for value restrictions.

   Conformance:  The property can be specified multiple times in a
      calendar component.

   Property parameters:  The X-RFCXXXX-JSNAME parameter MUST be set
      exactly once for this property.  The VALUE parameter MAY be set
      once, in which case its value MUST be URI.  Other IANA and non-
      standard property parameters can be specified on this property.

   Description:  This property maps a JSCalendar property to iCalendar.
      The property name is defined using the X-RFCXXXX-JSNAME parameter
      (Section 10.2.1).  The property value is encoded as a URL using
      the data scheme [RFC2397].  The media type MUST be specified as
      application/json and MUST NOT define parameters.  The property
      value MAY be any Javascript Object Notation (JSON) [RFC8259] value
      restricted by the I-JSON [RFC7493] profile, be that a JSON object,
      array, string, number, true or false.

   Format definition:  This property is defined by the following
      notation:















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        jsprop = "X-RFCXXXX-JSPROP" jsprop-param ":" jsprop-value CRLF

        jsprop-value  = "data:application/json" [";base64"] "," data
                        ; data is defined in RFC 2397, section 3

        jsprop-param  = *(
                        ; The following is MANDATORY and MUST NOT
                        ; occur more than once
                        jsname-param /
                        ;
                        ; The following is OPTIONAL,
                        ; but MUST NOT occur more than once.
                        ;
                        (";" "VALUE" "=" "URI" ) /
                        ;
                        ; The following is OPTIONAL,
                        ; and MAY occur more than once.
                        ;
                        (";" other-param)
                        ;
                        )

   Example(s):
      ;
      ; encodes the property
      ; ...
      ; "foo": {
      ;  "bar": 1234
      ; }
      ;
      X-RFCXXXX-JSPROP;X-RFCXXXX-JSNAME="foo"
       :data:application/json;base64,eyJiYXIiOiAxMjM0fQ==

10.1.2.  X-RFCXXXX-PROP Property

   Property name:  X-RFCXXXX-PROP

   Purpose:  This property embeds simple-typed JSCalendar properties in
      iCalendar.

   Value type:  Default is none.  It MAY be set to BOOLEAN, FLOAT or
      INTEGER.

   Conformance:  The property can be specified multiple times in a
      calendar component.

   Property parameters:  The X-RFCXXXX-JSNAME parameter MUST be set




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      exactly once for this property.  The VALUE parameter MAY be set
      once, in which case its value MUST be BOOLEAN, FLOAT or INTEGER.
      Other IANA and non-standard property parameters can be specified
      on this property.

   Description:  This property maps a simple-valued JSCalendar property
      to iCalendar.  The property name is defined using the X-RFCXXXX-
      JSNAME parameter.  (Section 10.2.1).  The property value is set by
      the following rules:

      *  If the JSON property value is a string and its contents solely
         consists of characters defined in the value ABNF of Section 3.1
         of [RFC5545], then the iCalendar property value is a verbatim
         copy of the JSON property value.  The VALUE parameter MUST NOT
         be set.

      *  If the JSON property value is a number without fractional and
         exponent, then the iCalendar property value is a verbatim copy
         of the JSON property value.  The VALUE parameter SHOULD be
         INTEGER if the JSON property is known to only allow integer
         values.  Otherwise the parameter value MUST be FLOAT.

      *  If the JSON property value is a number with fractional or
         exponent, then the iCalendar property value is a verbatim copy
         of the JSON property value.  The VALUE parameter MUST be FLOAT.

      *  If the JSON property value is verbatim true then the iCalendar
         property value is TRUE, or false and FALSE, respectively.  The
         VALUE parameter MUST be BOOLEAN.

      *  If none of the above rules match, then the JSCalendar property
         MUST NOT map to the X-RFCXXXX-PROP property.  Instead, it MAY
         map to the X-RFCXXXX-JSPROP (Section 10.1.1) property.

   Format definition:  This property is defined by the following
      notation:

      jsprop-short = "X-RFCXXXX-PROP"
                        (
                          jsprop-string /
                          jsprop-int /
                          jsprop-float /
                          jsprop-bool
                        )

      jsprop-string = *(
                        ; The following is MANDATORY and MUST NOT
                        ; occur more than once



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                        jsname-param /
                        ;
                        ; The following MUST NOT occur
                        ;
                        (";" "VALUE" "=" valuetype ) /
                        ;
                        ; The following is OPTIONAL,
                        ; and MAY occur more than once.
                        ;
                        (";" other-param)
                        ;
                      )
                      ":" value ; defined in RFC5545, section 3.1

      jsprop-int =    *(
                        ; The following are MANDATORY and each MUST NOT
                        ; occur more than once
                          jsname-param /
                          ( "VALUE" "=" "INTEGER" )
                        ;
                        ; The following is OPTIONAL,
                        ; and MAY occur more than once.
                        ;
                        (";" other-param)
                        ;
                      )
                      ":" integer ; defined in RFC5545, section 3.3.8

      jsprop-float =  *(
                        ; The following are MANDATORY and each MUST NOT
                        ; occur more than once
                          jsname-param /
                          ( "VALUE" "=" "FLOAT" )
                        ;
                        ; The following is OPTIONAL,
                        ; and MAY occur more than once.
                        ;
                        (";" other-param)
                        ;
                      )
                      ":" float ; defined in RFC5545, section 3.3.7

      jsprop-bool =  *(
                        ; The following are MANDATORY and each MUST NOT
                        ; occur more than once
                          jsname-param /
                          ( "VALUE" "=" "BOOLEAN" )
                        ;



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                        ; The following is OPTIONAL,
                        ; and MAY occur more than once.
                        ;
                        (";" other-param)
                        ;
                      )
                      ":" boolean ; defined in RFC5545, section 3.3.2

   Example(s):
      ;
      ; encodes the property
      ; ...
      ; "foo": 12.3
      ;
      X-RFCXXXX-PROP
       ;X-RFCXXXX-JSNAME="foo"
       ;VALUE=FLOAT
       :12.3

10.2.  New iCalendar Parameters

10.2.1.  X-RFCXXXX-JSNAME Parameter

   Parameter name:  X-RFCXXXX-JSNAME

   Purpose:  This parameter assigns a JSCalendar property name to
      JSCalendar data embedded in an iCalendar property.

   Format definition:
      jsname-param  = "X-RFCXXXX-JSNAME" "=" DQUOTE *QSAFE-CHAR DQUOTE

   Description:  This parameter is set on a X-RFCXXXX-JSPROP or X-
      RFCXXXX-PROP property.  It assigns the JSCalendar property name to
      the value embedded in the iCalendar property value.  The parameter
      value contains the verbatim name of the JSCalendar property.  It
      MUST be quoted to preserve case.

   Example(s):
        X-RFCXXXX-PROP;X-RFCXXXX-JSNAME="fooBar":baz

11.  JsCalendar base spec updates

   *  Make title and description optional in an alert.  Used to hold
      SUMMARY and DESCRIPTION if present.







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12.  Security Considerations

   The same security considerations as for [RFC8984] apply.

13.  IANA Considerations

   None.

14.  Acknowledgments

   The authors would like to thank the members of CalConnect for their
   valuable contributions.  This specification originated from the work
   of the API technical committee of CalConnect, the Calendaring and
   Scheduling Consortium.

15.  References

15.1.  Normative References

   [draft-ietf-calext-ical-relations]
              "Support for iCalendar Relationships",
              <https://tools.ietf.org/html/draft-ietf-calext-ical-
              relations>.

   [draft-ietf-calext-jscalendarbis]
              "JSCalendar: A JSON Representation of Calendar Data",
              <https://tools.ietf.org/html/draft-ietf-calext-
              jscalendarbis>.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC2397]  Masinter, L., "The "data" URL scheme", RFC 2397,
              DOI 10.17487/RFC2397, August 1998,
              <https://www.rfc-editor.org/info/rfc2397>.

   [RFC4648]  Josefsson, S., "The Base16, Base32, and Base64 Data
              Encodings", RFC 4648, DOI 10.17487/RFC4648, October 2006,
              <https://www.rfc-editor.org/info/rfc4648>.

   [RFC5545]  Desruisseaux, B., Ed., "Internet Calendaring and
              Scheduling Core Object Specification (iCalendar)",
              RFC 5545, DOI 10.17487/RFC5545, September 2009,
              <https://www.rfc-editor.org/info/rfc5545>.





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   [RFC5546]  Daboo, C., Ed., "iCalendar Transport-Independent
              Interoperability Protocol (iTIP)", RFC 5546,
              DOI 10.17487/RFC5546, December 2009,
              <https://www.rfc-editor.org/info/rfc5546>.

   [RFC6638]  Daboo, C. and B. Desruisseaux, "Scheduling Extensions to
              CalDAV", RFC 6638, DOI 10.17487/RFC6638, June 2012,
              <https://www.rfc-editor.org/info/rfc6638>.

   [RFC6868]  Daboo, C., "Parameter Value Encoding in iCalendar and
              vCard", RFC 6868, DOI 10.17487/RFC6868, February 2013,
              <https://www.rfc-editor.org/info/rfc6868>.

   [RFC7265]  Kewisch, P., Daboo, C., and M. Douglass, "jCal: The JSON
              Format for iCalendar", RFC 7265, DOI 10.17487/RFC7265, May
              2014, <https://www.rfc-editor.org/info/rfc7265>.

   [RFC7493]  Bray, T., Ed., "The I-JSON Message Format", RFC 7493,
              DOI 10.17487/RFC7493, March 2015,
              <https://www.rfc-editor.org/info/rfc7493>.

   [RFC7986]  Daboo, C., "New Properties for iCalendar", RFC 7986,
              DOI 10.17487/RFC7986, October 2016,
              <https://www.rfc-editor.org/info/rfc7986>.

   [RFC8259]  Bray, T., Ed., "The JavaScript Object Notation (JSON) Data
              Interchange Format", STD 90, RFC 8259,
              DOI 10.17487/RFC8259, December 2017,
              <https://www.rfc-editor.org/info/rfc8259>.

   [RFC8984]  Jenkins, N. and R. Stepanek, "JSCalendar: A JSON
              Representation of Calendar Data", RFC 8984,
              DOI 10.17487/RFC8984, July 2021,
              <https://www.rfc-editor.org/info/rfc8984>.

   [RFC9073]  Douglass, M., "Event Publishing Extensions to iCalendar",
              RFC 9073, DOI 10.17487/RFC9073, August 2021,
              <https://www.rfc-editor.org/info/rfc9073>.

   [RFC9074]  Daboo, C. and K. Murchison, Ed., ""VALARM" Extensions for
              iCalendar", RFC 9074, DOI 10.17487/RFC9074, August 2021,
              <https://www.rfc-editor.org/info/rfc9074>.

15.2.  Informative References

   [TZDB]     IANA, "Time Zone Database",
              <https://www.iana.org/time-zones>.




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Authors' Addresses

   Robert Stepanek
   FastMail
   PO Box 234
   Collins St West
   Melbourne  VIC 8007
   Australia
   Email: rsto@fastmailteam.com
   URI:   https://www.fastmail.com


   Michael Douglass
   Bedework Commercial Services
   226 3rd Street
   Troy, NY 12180
   United States of America
   Email: mdouglass@bedework.com
   URI:   http://bedework.com
































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