Calendaring extensions R. Stepanek
Internet-Draft Fastmail
Updates: 5545, jscalendarbis (if approved) 2 November 2026
Intended status: Standards Track
Expires: 6 May 2027
JSCalendar: Converting from and to iCalendar
draft-ietf-calext-jscalendar-icalendar-29
Abstract
This document defines how to convert calendaring information between
the JSCalendar and iCalendar data formats. It considers every
JSCalendar and iCalendar element registered at IANA at the time of
publication. It defines conversion rules for all elements that are
common to both formats, as well as how convert arbitrary or unknown
JSCalendar and iCalendar elements. This document updates RFC 5545
("iCalendar") and jscalendarbis ("JSCalendar") by defining new
properties and parameters for JSCalendar and iCalendar conversion.
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
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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 6 May 2027.
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document authors. All rights reserved.
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Please review these documents carefully, as they describe your rights
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1. Notational Conventions . . . . . . . . . . . . . . . . . 4
1.2. Scope and Goals . . . . . . . . . . . . . . . . . . . . . 4
1.3. How to Read the Examples . . . . . . . . . . . . . . . . 5
1.3.1. iCalendar Examples . . . . . . . . . . . . . . . . . 5
1.3.2. JSCalendar Examples . . . . . . . . . . . . . . . . . 7
1.3.3. Conversion Examples . . . . . . . . . . . . . . . . . 9
1.4. Lossy versus Lossless Conversion . . . . . . . . . . . . 9
2. Converting iCalendar to JSCalendar . . . . . . . . . . . . . 10
2.1. General rules . . . . . . . . . . . . . . . . . . . . . . 10
2.1.1. iCalendar Objects . . . . . . . . . . . . . . . . . . 10
2.1.2. Recurring Components . . . . . . . . . . . . . . . . 12
2.1.3. JSCalendar Ids . . . . . . . . . . . . . . . . . . . 17
2.1.4. Timezone identifiers . . . . . . . . . . . . . . . . 17
2.1.5. DATE and DATE-TIME . . . . . . . . . . . . . . . . . 18
2.2. Components . . . . . . . . . . . . . . . . . . . . . . . 18
2.2.1. PARTICIPANT . . . . . . . . . . . . . . . . . . . . . 18
2.2.2. VALARM . . . . . . . . . . . . . . . . . . . . . . . 20
2.2.3. VEVENT . . . . . . . . . . . . . . . . . . . . . . . 22
2.2.4. VLOCATION . . . . . . . . . . . . . . . . . . . . . . 25
2.2.5. VTODO . . . . . . . . . . . . . . . . . . . . . . . . 27
2.3. Properties . . . . . . . . . . . . . . . . . . . . . . . 30
2.3.1. ACKNOWLEDGED . . . . . . . . . . . . . . . . . . . . 30
2.3.2. ACTION . . . . . . . . . . . . . . . . . . . . . . . 31
2.3.3. ATTACH . . . . . . . . . . . . . . . . . . . . . . . 33
2.3.4. ATTENDEE . . . . . . . . . . . . . . . . . . . . . . 34
2.3.5. CALENDAR-ADDRESS . . . . . . . . . . . . . . . . . . 40
2.3.6. CATEGORIES . . . . . . . . . . . . . . . . . . . . . 41
2.3.7. CLASS . . . . . . . . . . . . . . . . . . . . . . . . 42
2.3.8. COLOR . . . . . . . . . . . . . . . . . . . . . . . . 43
2.3.9. CONCEPT . . . . . . . . . . . . . . . . . . . . . . . 44
2.3.10. CONFERENCE . . . . . . . . . . . . . . . . . . . . . 44
2.3.11. COORDINATES . . . . . . . . . . . . . . . . . . . . . 45
2.3.12. CREATED . . . . . . . . . . . . . . . . . . . . . . . 46
2.3.13. DESCRIPTION . . . . . . . . . . . . . . . . . . . . . 46
2.3.14. DTEND . . . . . . . . . . . . . . . . . . . . . . . . 47
2.3.15. DTSTAMP . . . . . . . . . . . . . . . . . . . . . . . 49
2.3.16. DTSTART . . . . . . . . . . . . . . . . . . . . . . . 50
2.3.17. DUE . . . . . . . . . . . . . . . . . . . . . . . . . 51
2.3.18. DURATION . . . . . . . . . . . . . . . . . . . . . . 54
2.3.19. ESTIMATED-DURATION . . . . . . . . . . . . . . . . . 54
2.3.20. EXDATE . . . . . . . . . . . . . . . . . . . . . . . 54
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2.3.21. GEO . . . . . . . . . . . . . . . . . . . . . . . . . 55
2.3.22. IMAGE . . . . . . . . . . . . . . . . . . . . . . . . 59
2.3.23. LAST-MODIFIED . . . . . . . . . . . . . . . . . . . . 60
2.3.24. LINK . . . . . . . . . . . . . . . . . . . . . . . . 61
2.3.25. LOCATION . . . . . . . . . . . . . . . . . . . . . . 62
2.3.26. LOCATION-TYPE . . . . . . . . . . . . . . . . . . . . 64
2.3.27. METHOD . . . . . . . . . . . . . . . . . . . . . . . 65
2.3.28. NAME . . . . . . . . . . . . . . . . . . . . . . . . 66
2.3.29. ORGANIZER . . . . . . . . . . . . . . . . . . . . . . 67
2.3.30. PERCENT-COMPLETE . . . . . . . . . . . . . . . . . . 72
2.3.31. PRIORITY . . . . . . . . . . . . . . . . . . . . . . 73
2.3.32. PRODID . . . . . . . . . . . . . . . . . . . . . . . 73
2.3.33. RDATE . . . . . . . . . . . . . . . . . . . . . . . . 74
2.3.34. RECURRENCE-ID . . . . . . . . . . . . . . . . . . . . 76
2.3.35. RELATED-TO . . . . . . . . . . . . . . . . . . . . . 77
2.3.36. RRULE . . . . . . . . . . . . . . . . . . . . . . . . 79
2.3.37. SEQUENCE . . . . . . . . . . . . . . . . . . . . . . 81
2.3.38. SHOW-WITHOUT-TIME . . . . . . . . . . . . . . . . . . 82
2.3.39. STATUS . . . . . . . . . . . . . . . . . . . . . . . 82
2.3.40. SOURCE . . . . . . . . . . . . . . . . . . . . . . . 83
2.3.41. STYLED-DESCRIPTION . . . . . . . . . . . . . . . . . 84
2.3.42. SUMMARY . . . . . . . . . . . . . . . . . . . . . . . 84
2.3.43. TRANSP . . . . . . . . . . . . . . . . . . . . . . . 85
2.3.44. TRIGGER . . . . . . . . . . . . . . . . . . . . . . . 86
2.3.45. UID . . . . . . . . . . . . . . . . . . . . . . . . . 88
2.3.46. URL . . . . . . . . . . . . . . . . . . . . . . . . . 88
3. Converting JSCalendar to iCalendar . . . . . . . . . . . . . 89
3.1. Alert . . . . . . . . . . . . . . . . . . . . . . . . . . 89
3.2. Event and Task . . . . . . . . . . . . . . . . . . . . . 89
3.3. Group . . . . . . . . . . . . . . . . . . . . . . . . . . 93
3.4. Link . . . . . . . . . . . . . . . . . . . . . . . . . . 95
3.5. Location . . . . . . . . . . . . . . . . . . . . . . . . 96
3.6. Participant . . . . . . . . . . . . . . . . . . . . . . . 97
3.7. VirtualLocation . . . . . . . . . . . . . . . . . . . . . 100
4. Updates to iCalendar . . . . . . . . . . . . . . . . . . . . 101
4.1. New Properties . . . . . . . . . . . . . . . . . . . . . 101
4.1.1. JSID . . . . . . . . . . . . . . . . . . . . . . . . 101
4.1.2. JSPROP . . . . . . . . . . . . . . . . . . . . . . . 102
4.2. New Parameters . . . . . . . . . . . . . . . . . . . . . 105
4.2.1. JSID . . . . . . . . . . . . . . . . . . . . . . . . 105
4.2.2. JSPTR . . . . . . . . . . . . . . . . . . . . . . . . 106
5. Updates to JSCalendar . . . . . . . . . . . . . . . . . . . . 106
5.1. New Properties . . . . . . . . . . . . . . . . . . . . . 106
5.1.1. iCalendar . . . . . . . . . . . . . . . . . . . . . . 106
6. Security Considerations . . . . . . . . . . . . . . . . . . . 109
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 109
7.1. Changes to the "iCalendar Element Registries" . . . . . . 109
7.2. Changes to the "JSCalendar Registries" . . . . . . . . . 110
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8. References . . . . . . . . . . . . . . . . . . . . . . . . . 114
8.1. Normative References . . . . . . . . . . . . . . . . . . 114
8.2. Informative References . . . . . . . . . . . . . . . . . 116
Appendix A. Discrepancies between iCalendar and JSCalendar . . . 116
A.1. Unsupported iCalendar Elements . . . . . . . . . . . . . 117
A.1.1. Components . . . . . . . . . . . . . . . . . . . . . 117
A.1.2. Properties by Component . . . . . . . . . . . . . . . 117
A.1.3. Subcomponents by Component . . . . . . . . . . . . . 120
A.1.4. Properties by Value Type . . . . . . . . . . . . . . 120
A.1.5. Parameters by Property . . . . . . . . . . . . . . . 120
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 122
1. Introduction
1.1. Notational Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in
BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
The ABNF definitions in this document use the notations of [RFC5234].
ABNF rules not defined in this document either are defined in
[RFC5234] or [RFC5545].
1.2. Scope and Goals
This document outlines how to convert between the iCalendar [RFC5545]
and JSCalendar [JSCALENDAR] data formats. It describes which
elements are common to both, but also highlights where the two
formats differ. For each common element, it defines a conversion
rule and includes an example of how to convert that element. All
iCalendar and JSCalendar elements currently registered at IANA are in
scope, but not all of these elements are common to both formats.
For elements that have no counterpart in the other format, it is the
goal of this document to define how to preserve them during
conversion, but in general it is not the goal to achieve this by
defining new standard elements. Instead, this document updates
[RFC5545] and [JSCALENDAR] by defining iCalendar and JSCalendar
elements to preserve elements that have no equivalent in the other
format. These conversion-specific properties are defined in
Section 4.1.2 for iCalendar, and Section 5.1.1 for JSCalendar.
Appendix A further outlines the discrepancies between the two
formats.
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1.3. How to Read the Examples
Later sections contain examples that illustrate how to convert
between the iCalendar and JSCalendar data formats. The notation of
these examples is such that their main points should be clear to the
reader, but their contents can also be parsed for automated testing.
The following sections define the notation for such examples.
1.3.1. iCalendar Examples
An iCalendar example contains either an extract or a complete
representation of iCalendar data. It always represents an iCalendar
object, even if the example only depicts non-VCALENDAR components or
properties. The following rules apply:
* An example that only contains iCalendar properties implicitly
represents a VEVENT component having these properties set and that
is part of a VCALENDAR component.
* An example that only contains one or more VEVENT, VTODO, VJOURNAL,
FREEBUSY or VTIMEZONE components implicitly represents a VCALENDAR
component that contains them. An example that only contains one
or more other components implicitly represents a VEVENT component
having these components set and that is part of a VCALENDAR
components.
* An example that only contains VEVENT or VTODO components
implicitly represents a VCALENDAR component that contains them.
* An example that only contains a VCALENDAR component but no
contained components implicitly represents a VCALENDAR component
that contains a VEVENT component.
* Implicit components (those without a BEGIN and END, or omitted
completely) are assumed to contain all mandatory properties with
some value, but the actual value is irrelevant for the example.
Figures 1, 2, and 3 contain three examples, all of which represent
the same iCalendar data. In Figure 1, both the VEVENT component and
VCALENDAR component are implicit. In Figure 2, only the VCALENDAR
component and its mandatory properties are implicit. Figure 3
depicts a complete VCALENDAR component, nothing is implicit.
SUMMARY:hello
Figure 1: Example for implicit VCALENDAR and VEVENT components
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BEGIN:VEVENT
DTSTAMP:20060102T030405Z
DTSTART:20060102T030405Z
SUMMARY:hello
UID:CC0A494A-6E07-4827-8294-0752DD1ECFA4
END:VEVENT
Figure 2: Example for an implicit VCALENDAR component
BEGIN:VCALENDAR
PRODID:-//FOO//bar//EN
VERSION:2.0
BEGIN:VEVENT
DTSTAMP:20060102T030405Z
DTSTART:20060102T030405Z
SUMMARY:hello
UID:CC0A494A-6E07-4827-8294-0752DD1ECFA4
END:VEVENT
END:VCALENDAR
Figure 3: Example for explicit VCALENDAR and VEVENT components
A line containing just the value ... stands for any other properties
that might be present in a component but are irrelevant for this
example. This includes mandatory properties as described for
implicit components, but the value ... does not represent a property
in a component for which at least one same-named property is
explicitly stated for that component in the example. The line ... at
the end of the example additionally stands for any END content lines
to complete components that started with BEGIN content lines, and any
of their missing mandatory properties. Figure 4 illustrates this as
an alternative representation for the examples of Figures 1, 2, and
3.
BEGIN:VCALENDAR
BEGIN:VEVENT
SUMMARY:hello
...
Figure 4: Example for additional properties and component ENDs
represented by ...
A line starting with a single space represents the continuation of a
folded content line (Section 3.1 of [RFC5545]). Figure 5 illustrates
this.
SUMMARY:he
llo
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Figure 5: Example for a folded content line
1.3.2. JSCalendar Examples
A JSCalendar example always represents a Group object, even if the
example only depicts one of the Group entries or properties. E.g.,
an example containing only an Alert object is implied to be the sole
value of the "alerts" property of an Event object, which is implied
to be the sole list member in the "entries" property of a Group
object. The Group object has its "version" property set to "2.0",
unless the example explicitly defines a complete Group object.
JSCalendar objects are depicted either explicitly or implicitly. An
explicit JSCalendar object starts and ends with braces. An implicit
JSCalendar object omits braces, it only consists of JSON name/value
pairs, separated by comma.
An implicit JSCalendar object is assumed to be of type Event, unless
it contains the "@type" property with a different value. It is
assumed to contain all mandatory properties with some value; if they
are not depicted, their actual value is irrelevant for the main point
of the example.
Figures 6, 7, 8, and 9 illustrate this with multiple examples, all of
which represent the same JSCalendar data. Figure 6 contains an
implicit JSCalendar object of type Event. Figure 7 contains an
implicit JSCalendar object with a "@type" property. Figure 8
contains an explicit Event object but the Group object containing it
is omitted. Figure 9 contains the full Group object, nothing is
omitted.
"title": "hello"
Figure 6: Example for an implicit JSCalendar object of type Event
"@type": "Event",
"title": "hello"
Figure 7: Example for an implicit JSCalendar object with "@type"
property
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{
"@type": "Event",
"title": "hello",
"start": "2006-01-02T03:04:05",
"timeZone": "Etc/UTC",
"uid": "CC0A494A-6E07-4827-8294-0752DD1ECFA4",
"updated": "2006-01-02T03:04:05Z"
}
Figure 8: Example for an explicit Event object with implicit
Group object
{
"@type": "Group",
"version": "2.0",
"entries": [
{
"@type": "Event",
"title": "hello",
"start": "2006-01-02T03:04:05",
"timeZone": "Etc/UTC",
"uid": "CC0A494A-6E07-4827-8294-0752DD1ECFA4",
"updated": "2006-01-02T03:04:05Z"
}
]
}
Figure 9: Example for an explicit Group object
A property with name "..." and value "" stands for additional
properties that might be present in a JSCalendar object but are
irrelevant for this example, including mandatory properties. The
"..." property requires the "@type" property to be set. Figure 10
illustrates this as an alternative representation for the examples of
Figures 6, 7, 8, and 9.
{
"@type": "Event",
"title": "hello",
"...": ""
}
Figure 10: Example for additional properties represented by ...
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1.3.3. Conversion Examples
A conversion example depicts iCalendar data together with the
JSCalendar data it converts to. The iCalendar data follows the
notation defined in Section 1.3.1, the JSCalendar data follows the
notation defined in Section 1.3.2.
The iCalendar data is preceded by a line containing just
--- iCalendar:, and the JSCalendar data is preceded by a line
containing just --- JSCalendar:. These marker lines are not part of
the example data. Empty lines are not part of the example data
either and are ignored. Figure 11 illustrates this.
--- iCalendar:
SUMMARY:hello
--- JSCalendar:
"title": "hello"
Figure 11: Example for the notation of a conversion example
1.4. Lossy versus Lossless Conversion
This document outlines how to convert iCalendar elements to
JSCalendar elements, and the other way round. Many of these can be
represented by standard elements in both formats, meaning that they
are registered in the iCalendar and JSCalendar IANA registries and
differ from the special-purpose elements introduced in Section 4 and
Section 5. Still, a number of elements in either format have no
standard counterpart in the other. When converting between between
iCalendar and JSCalendar, implementations MAY choose to only convert
elements that have standard element in the target format, or aim to
preserve as many elements as possible.
When to choose between lossy and lossless conversion is
implementation-specific. For example:
* For lossy conversion, an implementation that internally stores
calendar data in JSCalendar format might only want to convert to a
subset of iCalendar elements for iMIP scheduling [RFC6047]. In
this case, it might not make use any of the conversion-specific
iCalendar properties introduced in Section 4.
* For lossless conversion, an implementation that internally stores
calendar data in iCalendar format might want to convert without
loss to JSCalendar when updating calendar events with JMAP
[JMAP-CAL]. For that, it can use the conversion-specific
properties defined in Section 5.
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All the examples in this document illustrate lossless conversion, if
not explicitly stated otherwise in the example.
2. Converting iCalendar to JSCalendar
2.1. General rules
2.1.1. iCalendar Objects
Section 3.4 of [RFC5545] allows for an iCalendar stream to contain
one or more iCalendar objects. In contrast, this specification only
defines conversion for streams consisting of a single iCalendar
object. Converting streams of multiple iCalendar objects is
implementation-specific. All following sections of this document use
the terms "iCalendar object" and "VCALENDAR component"
interchangeably.
The VCALENDAR component [RFC5545] (Section 3.4) converts to a Group
object [JSCALENDAR] (Section 2.3). Its properties convert as
follows:
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+====================+==========================+=========+
| iCalendar property | JSCalendar property | Section |
+====================+==========================+=========+
| ATTACH | links | 2.3.3 |
+--------------------+--------------------------+---------+
| CATEGORIES | keywords | 2.3.6 |
+--------------------+--------------------------+---------+
| COLOR | color | 2.3.8 |
+--------------------+--------------------------+---------+
| CONCEPT | categories | 2.3.9 |
+--------------------+--------------------------+---------+
| CREATED | created | 2.3.12 |
+--------------------+--------------------------+---------+
| DESCRIPTION | description | 2.3.13 |
+--------------------+--------------------------+---------+
| IMAGE | links | 2.3.22 |
+--------------------+--------------------------+---------+
| LAST-MODIFIED | updated | 2.3.23 |
+--------------------+--------------------------+---------+
| LINK | links | 2.3.24 |
+--------------------+--------------------------+---------+
| METHOD | entries/*/method | 2.3.27 |
+--------------------+--------------------------+---------+
| NAME | title | 2.3.28 |
+--------------------+--------------------------+---------+
| PRODID | prodId, entries/*/prodId | 2.3.32 |
+--------------------+--------------------------+---------+
| SOURCE | source | 2.3.40 |
+--------------------+--------------------------+---------+
| UID | uid | 2.3.45 |
+--------------------+--------------------------+---------+
| URL | links | 2.3.46 |
+--------------------+--------------------------+---------+
Table 1: Properties of the VCALENDAR component
Its components convert as follows:
+=====================+=====================+=========+
| iCalendar component | JSCalendar property | Section |
+=====================+=====================+=========+
| VEVENT | entries | 2.2.3 |
+---------------------+---------------------+---------+
| VTODO | entries | 2.2.5 |
+---------------------+---------------------+---------+
Table 2: Components of the VCALENDAR component
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Other properties or components MAY be converted to the "iCalendar"
property (Section 5.1.1) of the Group object.
The order of elements in the "entries" property is implementation-
specific, e.g. entries need not be in the same order as their source
components in the iCalendar object.
The following example illustrates how to convert the VCALENDAR
component:
--- iCalendar:
BEGIN:VCALENDAR
UID:41aa02b6-42d0-4f45-8cb4-8b5075be2e14
BEGIN:VEVENT
...
--- JSCalendar:
{
"@type": "Group",
"entries": [
{
"...": "",
"@type": "Event"
}
],
"uid": "41aa02b6-42d0-4f45-8cb4-8b5075be2e14",
"...": ""
}
Figure 12: Converting the VCALENDAR component
2.1.2. Recurring Components
Components in an iCalendar object generally convert to distinct
JSCalendar objects. For example, two VEVENT components with
different UID property values in the same iCalendar object convert to
two separate Event objects in the Group object's entries. As an
exception to this rule, this does not apply to recurrence overrides,
defined as follows.
A VEVENT (or VTODO) component is a recurrence override if it has the
RECURRENCE-ID property set, and the iCalendar object contains a
VEVENT (or VTODO) component that does not have the RECURRENCE-ID but
the RRULE property set, and the UID property values of the two
components are equal. The component without the RECURRENCE-ID
property is in that case referred to as the "main component".
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The main component converts to an entry in the Group object's
"entries" property.
The recurrence override converts to the converted main component's
"recurrenceOverrides" property. Its RECURRENCE-ID property value
converts to the key in the "recurrenceOverrides" property. The value
of the "recurrenceOverrides" property at that key is a PatchObject
that transforms the converted main component into the converted
recurrence override, but it MUST NOT contain any of the patches that
are forbidden for the "recurrenceOverrides" property [JSCALENDAR]
(Section 3.3.4).
The following example illustrates how to convert a main component and
its recurrence override:
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--- iCalendar:
BEGIN:VCALENDAR
...
BEGIN:VEVENT
UID:F4257E1D-5461-4EF6-840F-9DFC653EB559
RRULE:FREQ=DAILY
DTSTART;TZID=Europe/Berlin:20240101T140000
...
END:VEVENT
BEGIN:VEVENT
UID:F4257E1D-5461-4EF6-840F-9DFC653EB559
RECURRENCE-ID;TZID=Europe/Berlin:20240202T140000
DTSTART;TZID=Europe/Berlin:20240202T160000
...
END:VEVENT
END:VCALENDAR
--- JSCalendar:
{
"@type": "Group",
"entries": [
{
"...": "",
"@type": "Event",
"recurrenceOverrides": {
"2024-02-02T14:00:00": {
"start": "2024-02-02T16:00:00"
}
},
"recurrenceRule": {
"@type": "RecurrenceRule",
"frequency": "daily"
},
"start": "2024-01-01T14:00:00",
"timeZone": "Europe/Berlin",
"uid": "F4257E1D-5461-4EF6-840F-9DFC653EB559"
}
],
"...": ""
}
Figure 13: Converting VEVENT recurrence overrides
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A VEVENT (or VTODO) component is a stand-alone recurrence instance if
it has the RECURRENCE-ID property set and the iCalendar object does
not contain its related main component. Each stand-alone recurrence
instance converts to a distinct Event (or Task) object in the Group
object's "entries" property. The "recurrenceId" property MUST be
set.
The following example illustrates how to convert stand-alone
recurrence instances:
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--- iCalendar:
BEGIN:VCALENDAR
...
BEGIN:VEVENT
UID:F4257E1D-5461-4EF6-840F-9DFC653EB559
RECURRENCE-ID;TZID=Europe/Berlin:20240202T140000
DTSTART;TZID=Europe/Berlin:20240202T160000
...
END:VEVENT
BEGIN:VEVENT
UID:F4257E1D-5461-4EF6-840F-9DFC653EB559
RECURRENCE-ID;TZID=Europe/Berlin:20240103T140000
DTSTART;TZID=Europe/Berlin:20240103T170000
...
END:VEVENT
END:VCALENDAR
--- JSCalendar:
{
"@type": "Group",
"entries": [
{
"...": "",
"@type": "Event",
"recurrenceId": "2024-02-02T14:00:00",
"recurrenceIdTimeZone": "Europe/Berlin",
"start": "2024-02-02T16:00:00",
"timeZone": "Europe/Berlin",
"uid": "F4257E1D-5461-4EF6-840F-9DFC653EB559"
},
{
"...": "",
"@type": "Event",
"recurrenceId": "2024-01-03T14:00:00",
"recurrenceIdTimeZone": "Europe/Berlin",
"start": "2024-01-03T17:00:00",
"timeZone": "Europe/Berlin",
"uid": "F4257E1D-5461-4EF6-840F-9DFC653EB559"
}
],
"...": ""
}
Figure 14: Converting VEVENT recurrence instances
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2.1.3. JSCalendar Ids
JSCalendar generally uses JSON objects to represent a collection of
same-typed values. The keys are of type Id [JSCALENDAR]
(Section 1.5.1), the values are JSCalendar object types. If an
iCalendar element converts to a value in such a collection then an
implementation needs to choose an identifier as key.
If the JSID parameter (Section 4.2.1) or JSID property
(Section 4.1.1) is set on a property or component, then its value
MUST be used as key when converting that element from iCalendar to
JSCalendar. In absence of the JSID parameter or property key
generation is implementation-specific.
Some sections later in this document describe key generation schemes
for specific iCalendar elements by making use of UUID Version 5 with
SHA1 hash [RFC9562] (Section 5.5). The Namespace ID to generate such
keys is "7f1e1965-ae73-4454-b088-232c90730ce2". These key generation
schemes are not mandatory, nor is making use of that particular
Namespace ID when using UUID Version 5 (UUIDv5) as keys.
Irrespective of the key generation scheme, all keys MUST be valid
according to the definition of the Id type. For consistency, keys
SHOULD be stable such that converting the same iCalendar data to
JSCalendar multiple times produces the same keys.
2.1.4. Timezone identifiers
Converting temporal properties such as DTSTART, DTEND, and
RECURRENCE-ID requires to not only determine the date and time of the
property value, but also the timezone it references.
If the property value type is DATE [RFC5545] (Section 3.3.4) or
DATE-TIME in FORM #1: DATE WITH LOCAL TIME [RFC5545] (Section 3.3.5)
then the timezone is not set in JSCalendar.
If the property value type is DATE-TIME in FORM #2: DATE WITH UTC
TIME [RFC5545] (Section 3.3.5) then the timezone identifier is "Etc/
UTC" in JSCalendar.
If the property value type is DATE-TIME in FORM #3: DATE WITH LOCAL
TIME AND TIME ZONE REFERENCE [RFC5545] (Section 3.3.5) then the
timezone identifier is determined by the TZID parameter value as
follows:
If the TZID parameter value is equal to a name in the IANA Time Zone
Database [TZDB] then the timezone identifier is that verbatim name.
Otherwise, how to convert the TZID parameter value is implementation-
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specific: software libraries such as the International Components for
Unicode (https://icu.unicode.org/) support converting Microsoft time
zone names to IANA time zone identifiers. Alternatively, an
implementation might determine the name of an IANA time zone which
has identical time zone rules over the time span of the calendar
object.
Implementations MAY preserve a TZID parameter set to a non-IANA
timezone identifier and its related VTIMEZONE by use of the
"convertedProperties" and "components" properties (see
Section 5.1.1), but MUST NOT expect other implementations to consider
them when processing the calendar object.
2.1.5. DATE and DATE-TIME
iCalendar provides the DATE and DATE-TIME value types to distinguish
date-only from date-time values. JSCalendar only supports date-time
values.
When converting from iCalendar to JSCalendar, a property value of
type DATE-TIME converts to either a LocalDateTime or UTCDateTime,
depending on the JSCalendar property definition. A DATE value type
converts to a LocalDateTime with zero time.
Section 3.2 defines which iCalendar value type to choose when
converting from JSCalendar to iCalendar.
2.2. Components
2.2.1. PARTICIPANT
The PARTICIPANT component [RFC9073] (Section 7.1) in a VEVENT or
VTODO component converts to a Participant object [JSCALENDAR]
(Section 3.4.6). The converted object is set in the Event or Task
object's "participants" property.
The key of the Participant object MUST be the value of the JSID
property (Section 4.1.1), if set. If no JSID property but the
CALENDAR-ADDRESS property is set, then the key MAY be a UUIDv5
generated from the property value (see Section 2.1.3). Otherwise,
the key MAY be the UID property value. When converting to iCalendar,
implementations MAY omit setting the JSID property if key matches the
UUIDv5 of the CALENDAR-ADDRESS property value or the key matches the
UID property, and the key is not part of a JSON pointer in any JSPTR
parameter value.
Its properties convert as follows:
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+====================+=====================+=========+
| iCalendar property | JSCalendar property | Section |
+====================+=====================+=========+
| ATTACH | links | 2.3.3 |
+--------------------+---------------------+---------+
| CALENDAR-ADDRESS | calendarAddress | 2.3.5 |
+--------------------+---------------------+---------+
| DESCRIPTION | description | 2.3.13 |
+--------------------+---------------------+---------+
| LINK | links | 2.3.24 |
+--------------------+---------------------+---------+
| STYLED-DESCRIPTION | description | 2.3.41 |
+--------------------+---------------------+---------+
| SUMMARY | name | 2.3.42 |
+--------------------+---------------------+---------+
| URL | links | 2.3.46 |
+--------------------+---------------------+---------+
Table 3: Properties of the PARTICIPANT component
Other properties or components MAY be converted to the "iCalendar"
property (Section 5.1.1) of the Participant object. This includes
mandatory properties such as UID [RFC5545] (Section 3.8.4.7).
The following example illustrates how to convert the PARTICIPANT
component:
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--- iCalendar:
BEGIN:PARTICIPANT
UID:47AD2E1C-49D4-45DF-BD83-8398ACC7D8E2
DESCRIPTION:A participant
...
END:PARTICIPANT
--- JSCalendar:
"participants": {
"47AD2E1C-49D4-45DF-BD83-8398ACC7D8E2": {
"@type": "Participant",
"description": "A participant",
"iCalendar": {
"@type": "ICalComponent",
"name": "participant",
"properties": [
[
"uid",
{},
"text",
"47AD2E1C-49D4-45DF-BD83-8398ACC7D8E2"
]
]
}
}
}
Figure 15: Converting the PARTICIPANT component
2.2.2. VALARM
The VALARM component [RFC5545] (Section 3.6.6) in a VEVENT or VTODO
component converts to an Alert object [JSCALENDAR] (Section 3.5.1).
The converted object is set in the Event or Task object's "alerts"
property.
The key of the Alert object MUST be the value of the JSID property
(Section 4.1.1), if set. Otherwise, the key MAY be the value of the
UID property. When converting to iCalendar, implementations MAY omit
setting the JSID property if the key matches the value of the UID
property, and the key is not part of a JSON pointer in any JSPTR
parameter value.
Its properties convert as follows:
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+====================+=====================+===============+
| iCalendar property | JSCalendar property | Section |
+====================+=====================+===============+
| ACKNOWLEDGED | acknowledged | 2.3.1 |
+--------------------+---------------------+---------------+
| ACTION | action | 2.3.2, and |
| | | remarks below |
+--------------------+---------------------+---------------+
| RELATED-TO | relatedTo | 2.3.35 |
+--------------------+---------------------+---------------+
| TRIGGER | trigger | 2.3.44 |
+--------------------+---------------------+---------------+
Table 4: Properties of the VALARM component
Remarks:
* The ACTION property only converts if its value is EMAIL or
DISPLAY.
Other properties or components MAY be converted to the "iCalendar"
property (Section 5.1.1) of the Alert object. This includes
mandatory properties such as ATTENDEE [RFC5545] (Section 3.8.4.1),
DESCRIPTION [RFC5545] (Section 3.8.1.5), or SUMMARY [RFC5545]
(Section 3.8.1.12).
The following example illustrates how to convert the VALARM
component:
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--- iCalendar:
BEGIN:VALARM
UID:04DC2968-6468-4B92-BC09-5A17D7D3D4E
TRIGGER:-PT30M
ACTION:DISPLAY
DESCRIPTION:Breakfast meeting
END:VALARM
--- JSCalendar:
"alerts": {
"04DC2968-6468-4B92-BC09-5A17D7D3D4E": {
"@type": "Alert",
"iCalendar": {
"@type": "ICalComponent",
"name": "valarm",
"properties": [
[
"description",
{},
"text",
"Breakfast meeting"
],
[
"uid",
{},
"text",
"04DC2968-6468-4B92-BC09-5A17D7D3D4E"
]
]
},
"trigger": {
"@type": "OffsetTrigger",
"offset": "-PT30M"
},
"action": "display"
}
}
Figure 16: Converting the VALARM component
2.2.3. VEVENT
The VEVENT component [RFC5545] (Section 3.6.1) converts to a Event
object [JSCALENDAR] (Section 2.1). Its properties convert as
follows:
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+====================+==========================+=========+
| iCalendar property | JSCalendar property | Section |
+====================+==========================+=========+
| ATTACH | links | 2.3.3 |
+--------------------+--------------------------+---------+
| ATTENDEE | participants | 2.3.4 |
+--------------------+--------------------------+---------+
| CATEGORIES | keywords | 2.3.6 |
+--------------------+--------------------------+---------+
| CLASS | privacy | 2.3.7 |
+--------------------+--------------------------+---------+
| COLOR | color | 2.3.8 |
+--------------------+--------------------------+---------+
| CONCEPT | categories | 2.3.9 |
+--------------------+--------------------------+---------+
| CONFERENCE | virtualLocations | 2.3.10 |
+--------------------+--------------------------+---------+
| CREATED | created | 2.3.12 |
+--------------------+--------------------------+---------+
| DESCRIPTION | description | 2.3.13 |
+--------------------+--------------------------+---------+
| DTEND | duration, endTimeZone | 2.3.14 |
+--------------------+--------------------------+---------+
| DTSTAMP | updated | 2.3.15 |
+--------------------+--------------------------+---------+
| DTSTART | start | 2.3.16 |
+--------------------+--------------------------+---------+
| DURATION | duration | 2.3.18 |
+--------------------+--------------------------+---------+
| EXDATE | recurrenceOverrides | 2.3.20 |
+--------------------+--------------------------+---------+
| GEO | locations | 2.3.21 |
+--------------------+--------------------------+---------+
| IMAGE | links | 2.3.22 |
+--------------------+--------------------------+---------+
| LAST-MODIFIED | updated | 2.3.23 |
+--------------------+--------------------------+---------+
| LINK | links | 2.3.24 |
+--------------------+--------------------------+---------+
| LOCATION | locations | 2.3.25 |
+--------------------+--------------------------+---------+
| ORGANIZER | organizerCalendarAddress | 2.3.29 |
+--------------------+--------------------------+---------+
| PRIORITY | priority | 2.3.31 |
+--------------------+--------------------------+---------+
| RDATE | recurrenceOverrides | 2.3.33 |
+--------------------+--------------------------+---------+
| RECURRENCE-ID | recurrenceId | 2.3.34 |
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+--------------------+--------------------------+---------+
| RELATED-TO | relatedTo | 2.3.35 |
+--------------------+--------------------------+---------+
| RRULE | recurrenceRule | 2.3.36 |
+--------------------+--------------------------+---------+
| SEQUENCE | sequence | 2.3.37 |
+--------------------+--------------------------+---------+
| SHOW-WITHOUT-TIME | showWithoutTime | 2.3.38 |
+--------------------+--------------------------+---------+
| STATUS | status | 2.3.39 |
+--------------------+--------------------------+---------+
| STYLED-DESCRIPTION | description | 2.3.41 |
+--------------------+--------------------------+---------+
| SUMMARY | title | 2.3.42 |
+--------------------+--------------------------+---------+
| TRANSP | freeBusyStatus | 2.3.43 |
+--------------------+--------------------------+---------+
| UID | uid | 2.3.45 |
+--------------------+--------------------------+---------+
| URL | links | 2.3.46 |
+--------------------+--------------------------+---------+
Table 5: Properties of the VEVENT component
Its components convert as follows:
+=====================+=====================+=========+
| iCalendar component | JSCalendar property | Section |
+=====================+=====================+=========+
| VALARM | alerts | 2.2.2 |
+---------------------+---------------------+---------+
Table 6: Components of the VEVENT component
Other properties or components MAY be converted to the "iCalendar"
property (Section 5.1.1) of the Event object.
VEVENT components with different UID property values in the same
iCalendar object convert to different entries in the Group. They
sort in the same order as in the VCALENDAR component.
The following example illustrates how to convert the VEVENT
component:
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--- iCalendar:
BEGIN:VCALENDAR
...
BEGIN:VEVENT
UID:DE935D01-3DF7-4201-B61A-D77D05C8B21A
DTSTART:20060102T030405Z
...
END:VEVENT
BEGIN:VEVENT
UID:60BE3D6E-6383-473A-BCF1-3C43EA1FA571
...
END:VEVENT
END:VCALENDAR
--- JSCalendar:
{
"...": "",
"@type": "Group",
"entries": [
{
"@type": "Event",
"start": "2006-01-02T03:04:05",
"timeZone": "Etc/UTC",
"uid": "DE935D01-3DF7-4201-B61A-D77D05C8B21A",
"...": ""
},
{
"@type": "Event",
"uid": "60BE3D6E-6383-473A-BCF1-3C43EA1FA571",
"...": ""
}
]
}
Figure 17: Converting the VEVENT component
2.2.4. VLOCATION
The VLOCATION component [RFC9073] (Section 7.2) in a VEVENT or VTODO
component converts to a Location object [JSCALENDAR] (Section 3.2.5).
The converted object is set in the Event or Task object's "locations"
property.
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The key of the Location object MUST be the value of the JSID property
(Section 4.1.1), if set. Otherwise, the key MAY be the value of the
UID property. When converting to iCalendar, implementations MAY omit
setting the JSID property if the key matches the value of the UID
property, and the key is not part of a JSON pointer in any JSPTR
parameter value.
Its properties convert as follows:
+====================+=====================+=========+
| iCalendar property | JSCalendar property | Section |
+====================+=====================+=========+
| ATTACH | links | 2.3.3 |
+--------------------+---------------------+---------+
| COORDINATES | coordinates | 2.3.11 |
+--------------------+---------------------+---------+
| GEO | coordinates | 2.3.21 |
+--------------------+---------------------+---------+
| IMAGE | links | 2.3.22 |
+--------------------+---------------------+---------+
| LINK | links | 2.3.24 |
+--------------------+---------------------+---------+
| LOCATION-TYPE | locationTypes | 2.3.26 |
+--------------------+---------------------+---------+
| NAME | name | 2.3.28 |
+--------------------+---------------------+---------+
| URL | links | 2.3.46 |
+--------------------+---------------------+---------+
Table 7: Properties of the VLOCATION component
Other properties or components MAY be converted to the "iCalendar"
property (Section 5.1.1) of the Location object. This includes
mandatory properties such as UID [RFC5545] (Section 3.8.4.7).
The following example illustrates how to convert the VLOCATION
component:
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--- iCalendar:
BEGIN:VLOCATION
UID:4954DC22-5BD6-4E98-844D-0302982F54AC
NAME:The venue
STRUCTURED-DATA;VALUE=URI:
http://dir.example.com/venues/big-hall.vcf
...
END:VLOCATION
--- JSCalendar:
"locations": {
"4954DC22-5BD6-4E98-844D-0302982F54AC": {
"@type": "Location",
"name": "The venue",
"iCalendar": {
"@type": "ICalComponent",
"name": "vlocation",
"properties": [
[
"structured-data",
{},
"uri",
"http://dir.example.com/venues/big-hall.vcf"
],
[
"uid",
{},
"text",
"4954DC22-5BD6-4E98-844D-0302982F54AC"
]
]
}
}
}
Figure 18: Converting the VLOCATION component
2.2.5. VTODO
The VTODO component [RFC5545] (Section 3.6.2) converts to a Task
object [JSCALENDAR] (Section 2.2). Its properties convert as
follows:
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+====================+==========================+=========+
| iCalendar property | JSCalendar property | Section |
+====================+==========================+=========+
| ATTACH | links | 2.3.3 |
+--------------------+--------------------------+---------+
| ATTENDEE | participants | 2.3.4 |
+--------------------+--------------------------+---------+
| CATEGORIES | keywords | 2.3.6 |
+--------------------+--------------------------+---------+
| CLASS | privacy | 2.3.7 |
+--------------------+--------------------------+---------+
| COLOR | color | 2.3.8 |
+--------------------+--------------------------+---------+
| CONCEPT | categories | 2.3.9 |
+--------------------+--------------------------+---------+
| CONFERENCE | virtualLocations | 2.3.10 |
+--------------------+--------------------------+---------+
| CREATED | created | 2.3.12 |
+--------------------+--------------------------+---------+
| DESCRIPTION | description | 2.3.13 |
+--------------------+--------------------------+---------+
| DTSTAMP | updated | 2.3.15 |
+--------------------+--------------------------+---------+
| DTSTART | start | 2.3.16 |
+--------------------+--------------------------+---------+
| DUE | due | 2.3.17 |
+--------------------+--------------------------+---------+
| DURATION | duration | 2.3.18 |
+--------------------+--------------------------+---------+
| ESTIMATED-DURATION | estimatedDuration | 2.3.19 |
+--------------------+--------------------------+---------+
| EXDATE | recurrenceOverrides | 2.3.20 |
+--------------------+--------------------------+---------+
| GEO | locations | 2.3.21 |
+--------------------+--------------------------+---------+
| IMAGE | links | 2.3.22 |
+--------------------+--------------------------+---------+
| LAST-MODIFIED | updated | 2.3.23 |
+--------------------+--------------------------+---------+
| LINK | links | 2.3.24 |
+--------------------+--------------------------+---------+
| LOCATION | locations | 2.3.25 |
+--------------------+--------------------------+---------+
| ORGANIZER | organizerCalendarAddress | 2.3.29 |
+--------------------+--------------------------+---------+
| PERCENT-COMPLETE | percentComplete | 2.3.30 |
+--------------------+--------------------------+---------+
| PRIORITY | priority | 2.3.31 |
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+--------------------+--------------------------+---------+
| RDATE | recurrenceOverrides | 2.3.33 |
+--------------------+--------------------------+---------+
| RECURRENCE-ID | recurrenceId | 2.3.34 |
+--------------------+--------------------------+---------+
| RELATED-TO | relatedTo | 2.3.35 |
+--------------------+--------------------------+---------+
| RRULE | recurrenceRule | 2.3.36 |
+--------------------+--------------------------+---------+
| SEQUENCE | sequence | 2.3.37 |
+--------------------+--------------------------+---------+
| SHOW-WITHOUT-TIME | showWithoutTime | 2.3.38 |
+--------------------+--------------------------+---------+
| STYLED-DESCRIPTION | description | 2.3.41 |
+--------------------+--------------------------+---------+
| SUMMARY | title | 2.3.42 |
+--------------------+--------------------------+---------+
| TRANSP | freeBusyStatus | 2.3.43 |
+--------------------+--------------------------+---------+
| UID | uid | 2.3.45 |
+--------------------+--------------------------+---------+
| URL | links | 2.3.46 |
+--------------------+--------------------------+---------+
Table 8: Properties of the VTODO component
Its components convert as follows:
+=====================+=====================+=========+
| iCalendar component | JSCalendar property | Section |
+=====================+=====================+=========+
| VALARM | alerts | 2.2.2 |
+---------------------+---------------------+---------+
Table 9: Components of the VTODO component
Other properties or components MAY be converted to the "iCalendar"
property (Section 5.1.1) of the Task object.
VTODO components with different UID property values in the same
iCalendar object convert to different entries in the Group. They
sort in the same order as in the VCALENDAR component.
The following example illustrates how to convert the VTODO component:
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--- iCalendar:
BEGIN:VCALENDAR
BEGIN:VTODO
UID:83C80482-806D-41C4-8029-E438F793005D
DUE:20060102T030405Z
...
--- JSCalendar:
{
"...": "",
"@type": "Group",
"entries": [
{
"...": "",
"@type": "Task",
"due": "2006-01-02T03:04:05",
"timeZone": "Etc/UTC",
"uid": "83C80482-806D-41C4-8029-E438F793005D"
}
]
}
Figure 19: Converting the VTODO component
2.3. Properties
2.3.1. ACKNOWLEDGED
The ACKNOWLEDGED property [RFC9074] (Section 6.1) in a VALARM
component converts to the "acknowledged" property [JSCALENDAR]
(Section 3.5.1) of the Alert object.
The following example illustrates how to convert the ACKNOWLEDGED
property:
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--- iCalendar:
BEGIN:VEVENT
BEGIN:VALARM
ACKNOWLEDGED:20241002T114703Z
...
--- JSCalendar:
"alerts": {
"1204B2FA-E4A0-4335-B7CD-0DDC09C9B890": {
"@type": "Alert",
"acknowledged": "2024-10-02T11:47:03Z",
"...": ""
}
}
Figure 20: Converting the ACKNOWLEDGED property
2.3.2. ACTION
The ACTION property [RFC5545] (Section 3.8.6.1) in a VALARM component
converts to the "action" property [JSCALENDAR] (Section 3.5.1) of the
Alert object.
Its values convert as follows:
+=========+=========+
| ACTION | action |
+=========+=========+
| DISPLAY | display |
+---------+---------+
| EMAIL | email |
+---------+---------+
Table 10: Values of
the ACTION property
An ACTION property with value AUDIO or any other not listed in
Table 10 does not convert to the "action" property. Instead, the
property converts to the iCalendar/properties property
(Section 5.1.1) of the Alert.
The following example illustrates how to convert the ACTION property
with value DISPLAY:
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--- iCalendar:
BEGIN:VEVENT
BEGIN:VALARM
ACTION:DISPLAY
...
--- JSCalendar:
"alerts": {
"02E4CAD6-B7A7-4EE4-93A6-4AA5AFD080E2": {
"@type": "Alert",
"action": "display",
"...": ""
}
}
Figure 21: Converting the ACTION property for value DISPLAY
The following example illustrates how to convert the ACTION property
with value AUDIO:
--- iCalendar:
BEGIN:VEVENT
BEGIN:VALARM
ACTION:AUDIO
...
--- JSCalendar:
"alerts": {
"FC529A2B-D10F-461D-BDCF-55C77BB4B933": {
"@type": "Alert",
"iCalendar": {
"@type": "ICalComponent",
"name": "valarm",
"properties": [
[
"action",
{},
"text",
"AUDIO"
]
]
},
"...": ""
}
}
Figure 22: Converting the ACTION property for value AUDIO
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2.3.3. ATTACH
The ATTACH property [RFC5545] (Section 3.8.1.1) in a VEVENT, VTODO,
PARTICIPANT, VLOCATION, or VCALENDAR component converts to a Link
object [JSCALENDAR] (Section 1.5.11). The converted object is set in
the Event, Task, Participant, Location, or Group object's "links"
property. The "rel" property value is set to "enclosure".
The key of the Link object MUST be the value of the JSID parameter
(Section 4.2.1), if set. If no JSID parameter is set, then the key
MAY be the UUIDv5 generated from the property value (see
Section 2.1.3). When converting to iCalendar, implementations MAY
omit setting the JSID parameter if the key matches the UUIDv5 of the
ATTACH property value and the key is not part of a JSON pointer in
any JSPTR parameter value.
The ATTACH property value converts to the Link object's "href"
property. A value of type URI converts as-is. A value of type
BINARY converts to a URI in the "data" URL scheme ([RFC2397]. If the
FMTTYPE parameter is set on the ATTACH property, then the parameter
value MUST be set in the "mediatype" part of the data URL.
The ATTACH property parameters convert as follows:
+=====================+=====================+
| iCalendar parameter | JSCalendar property |
+=====================+=====================+
| FILENAME | title |
+---------------------+---------------------+
| FMTTYPE | contentType |
+---------------------+---------------------+
| SIZE | size |
+---------------------+---------------------+
Table 11: Parameters of the ATTACH property
These parameters are defined in [RFC8607]: FILENAME (Section 4.2),
SIZE (Section 4.1); and in [RFC5545]: FMTTYPE (Section 3.2.8).
The following example illustrates how to convert the ATTACH property
with a URI value:
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--- iCalendar:
ATTACH:https://example.com/foo.pdf
--- JSCalendar:
"links": {
"245708bf-8e07-5d3b-a5da-2974a63c3b91": {
"@type": "Link",
"href": "https://example.com/foo.pdf"
}
}
Figure 23: Converting the ATTACH property with URI value
The following example illustrates how to convert the ATTACH property
with a BINARY value:
--- iCalendar:
ATTACH;ENCODING=BASE64;VALUE=BINARY;FMTTYPE=application/octet-stream:
AAECAwQF
--- JSCalendar:
"links": {
"6c16f063-d57d-5692-8822-2dceec9f9487": {
"@type": "Link",
"href": "data:application/octet-stream;base64,AAECAwQF",
"contentType": "application/octet-stream",
"...": ""
}
}
Figure 24: Converting the ATTACH property with BINARY value
2.3.4. ATTENDEE
The ATTENDEE property [RFC5545] (Section 3.8.4.1) in a VEVENT or
VTODO component converts to a Participant object [JSCALENDAR]
(Section 3.4.6). The converted object is set in the Event or Task
object's "participants" property. The property value converts to the
Participant object's "calendarAddress" property.
The key of the Participant object MUST be the value of the JSID
parameter (Section 4.2.1), if set. If no JSID parameter is set, then
the key MAY be the UUIDv5 generated from the property value (see
Section 2.1.3). When converting to iCalendar, implementations MAY
omit setting the JSID parameter if the key matches the UUIDv5 of the
ATTENDEE property value and the key is not part of a JSON pointer in
any JSPTR parameter value.
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An ATTENDEE property and a PARTICIPANT component in the same
iCalendar component convert to the same Participant object, if their
converted "calendarAddress" property values are equal. How to deal
with conflicting values is implementation-specific.
The ATTENDEE property parameters convert as follows:
+=====================+=====================+====================+
| iCalendar parameter | JSCalendar property | Note |
+=====================+=====================+====================+
| CN | name | |
+---------------------+---------------------+--------------------+
| CUTYPE | kind | ROOM converts to |
| | | "location" |
+---------------------+---------------------+--------------------+
| DELEGATED-FROM | delegatedFrom | |
+---------------------+---------------------+--------------------+
| DELEGATED-TO | delegatedTo | |
+---------------------+---------------------+--------------------+
| EMAIL | email | |
+---------------------+---------------------+--------------------+
| MEMBER | memberOf | |
+---------------------+---------------------+--------------------+
| PARTSTAT | participationStatus | |
+---------------------+---------------------+--------------------+
| ROLE | roles | OWNER role defined |
| | | in [JSCAL-EXT] |
+---------------------+---------------------+--------------------+
| RSVP | expectReply | |
+---------------------+---------------------+--------------------+
| SENT-BY | sentBy | |
+---------------------+---------------------+--------------------+
Table 12: Parameters of the ATTENDEE property
These parameters are defined in [RFC5545]: CN (Section 3.2.2), CUTYPE
(Section 3.2.3), DELEGATED-FROM (Section 3.2.4), DELEGATED-TO
(Section 3.2.5), MEMBER (Section 3.2.11), PARTSTAT (Section 3.2.12),
ROLE (Section 3.2.16), RSVP (Section 3.2.17), SENT-BY
(Section 3.2.18); and in [RFC7986]: EMAIL (Section 6.2).
The PARTSTAT of an ATTENDEE property in a VTODO component converts
not only to the Participant object's "participationStatus" property,
but also to its "progress" property if the PARTSTAT parameter value
is specific for VTODO components:
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+==============+=====================+============+
| PARTSTAT | participationStatus | progress |
+==============+=====================+============+
| NEEDS-ACTION | needs-action | |
+--------------+---------------------+------------+
| ACCEPTED | accepted | |
+--------------+---------------------+------------+
| DECLINED | declined | |
+--------------+---------------------+------------+
| TENTATIVE | tentative | |
+--------------+---------------------+------------+
| DELEGATED | delegated | |
+--------------+---------------------+------------+
| COMPLETED | accepted | completed |
+--------------+---------------------+------------+
| IN-PROCESS | accepted | in-process |
+--------------+---------------------+------------+
| FAILED | accepted | failed |
+--------------+---------------------+------------+
Table 13: Converting the PARTSTAT parameter in
a VTODO component to Participant properties
These values are defined in [RFC5545]: NEEDS-ACTION, ACCEPTED,
DECLINED, TENTATIVE, DELEGATED, COMPLETED, IN-PROCESS
(Section 3.2.12); and in [RFC10051]: FAILED (Section 9.1).
The following example illustrates how to convert the ATTENDEE
property:
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--- iCalendar:
ATTENDEE;RSVP=TRUE;PARTSTAT=TENTATIVE;CN=Henry Cabot:
mailto:hcabot@example.com
ORGANIZER:mailto:organizer@example.com
--- JSCalendar:
"participants": {
"0b235cc4-f04d-5fc4-98a3-c066650b3fbf": {
"@type": "Participant",
"calendarAddress": "mailto:hcabot@example.com",
"name": "Henry Cabot",
"participationStatus": "tentative",
"expectReply": true
},
"251d3e9f-d83f-534c-8c45-c2896c75670c": {
"@type": "Participant",
"calendarAddress": "mailto:organizer@example.com",
"roles": {
"owner": true
}
}
},
"organizerCalendarAddress": "mailto:organizer@example.com"
Figure 25: Converting the ATTENDEE property
The following example illustrates how to convert the ATTENDEE
property together with a PARTICIPANT component for the same calendar
address:
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--- iCalendar:
BEGIN:PARTICIPANT
UID:6CF544E4-BBC7-45A2-97FF-DFD1908CCE40
CALENDAR-ADDRESS:mailto:foo@example.com
DESCRIPTION:some description
...
END:PARTICIPANT
ATTENDEE;RSVP=TRUE;PARTSTAT=TENTATIVE:mailto:foo@example.com
ORGANIZER:mailto:organizer@example.com
...
--- JSCalendar:
"participants": {
"59eb121c-e8f2-558a-9049-ef750a5976bd": {
"@type": "Participant",
"calendarAddress": "mailto:foo@example.com",
"participationStatus": "tentative",
"expectReply": true,
"description": "some description",
"iCalendar": {
"@type": "ICalComponent",
"name": "participant",
"properties": [
[
"uid",
{},
"text",
"6CF544E4-BBC7-45A2-97FF-DFD1908CCE40"
]
]
},
"...": ""
},
"251d3e9f-d83f-534c-8c45-c2896c75670c": {
"@type": "Participant",
"calendarAddress": "mailto:organizer@example.com",
"...": ""
}
},
"organizerCalendarAddress": "mailto:organizer@example.com"
Figure 26: Converting the ATTENDEE property and PARTICIPANT component
The following example illustrates how to convert the ATTENDEE
property with a participation status that is specific to VTODO
components:
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--- iCalendar:
BEGIN:VTODO
ATTENDEE;RSVP=TRUE;PARTSTAT=COMPLETED:mailto:foo@example.com
ORGANIZER:mailto:organizer@example.com
...
--- JSCalendar:
"@type": "Task",
"participants": {
"59eb121c-e8f2-558a-9049-ef750a5976bd": {
"@type": "Participant",
"calendarAddress": "mailto:foo@example.com",
"participationStatus": "accepted",
"progress": "completed",
"expectReply": true,
"...": ""
},
"251d3e9f-d83f-534c-8c45-c2896c75670c": {
"@type": "Participant",
"calendarAddress": "mailto:organizer@example.com",
"...": ""
}
},
"organizerCalendarAddress": "mailto:organizer@example.com"
Figure 27: Converting the ATTENDEE property with VTODO-specific
PARTSTAT
The following example illustrates how to convert the ATTENDEE
property with the OWNER role:
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--- iCalendar:
ATTENDEE;RSVP=TRUE:mailto:foo@example.com
ATTENDEE;ROLE=OWNER;RSVP=TRUE:mailto:bar@example.com
ORGANIZER:mailto:organizer@example.com
--- JSCalendar:
"participants": {
"59eb121c-e8f2-558a-9049-ef750a5976bd": {
"@type": "Participant",
"calendarAddress": "mailto:foo@example.com",
"expectReply": true
},
"5b6f4fa0-3695-53a7-904b-d0a6f8bc326f": {
"@type": "Participant",
"calendarAddress": "mailto:bar@example.com",
"expectReply": true,
"roles": {
"owner": true
}
}
},
"organizerCalendarAddress": "mailto:organizer@example.com"
Figure 28: Converting the ATTENDEE property with the OWNER role
2.3.5. CALENDAR-ADDRESS
The CALENDAR-ADDRESS property [RFC9073] (Section 6.4) in a
PARTICIPANT component converts to the "calendarAddress" property
[JSCALENDAR] (Section 3.4.6) of the Participant object.
Implementations MAY preserve the fact that a Participant object's
"calendarAddress" property converted from the CALENDAR-ADDRESS
property of a PARTICIPANT component, rather than an ATTENDEE
property. In this case, they MUST add an entry for the
"calendarAddress" property in the "iCalendar/convertedProperties"
property of the Participant object.
The following example illustrates how to convert the CALENDAR-ADDRESS
property:
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--- iCalendar:
BEGIN:PARTICIPANT
CALENDAR-ADDRESS:mailto:foo@example.com
UID:47AD2E1C-49D4-45DF-BD83-8398ACC7D8E2
...
END:PARTICIPANT
ORGANIZER:mailto:organizer@example.com
...
--- JSCalendar:
"participants": {
"59eb121c-e8f2-558a-9049-ef750a5976bd": {
"@type": "Participant",
"calendarAddress": "mailto:foo@example.com",
"iCalendar": {
"@type": "ICalComponent",
"name": "participant",
"convertedProperties": {
"calendarAddress": {
"@type": "ICalProperty",
"name": "calendar-address"
}
},
"properties": [
[
"uid",
{},
"text",
"47AD2E1C-49D4-45DF-BD83-8398ACC7D8E2"
]
]
}
},
"251d3e9f-d83f-534c-8c45-c2896c75670c": {
"@type": "Participant",
"calendarAddress": "mailto:organizer@example.com",
"...": ""
}
},
"organizerCalendarAddress": "mailto:organizer@example.com"
Figure 29: Converting the CALENDAR-ADDRESS property
2.3.6. CATEGORIES
The CATEGORIES property [RFC5545] (Section 3.8.1.2) in a VEVENT,
VTODO, or VCALENDAR component converts to the "keywords" property
[JSCALENDAR] (Section 3.2.10) of the Event, Task, or Group object.
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The list of category values converts to a set of keywords. The
values convert case-sensitively. All CATEGORIES properties in the
same iCalendar component convert to the "keywords" property in the
JSCalendar object.
The following example illustrates how to convert the CATEGORIES
property:
--- iCalendar:
CATEGORIES:Favorites
CATEGORIES:Meeting
--- JSCalendar:
"keywords": {
"Favorites": true,
"Meeting": true
}
Figure 30: Converting the CATEGORIES property
2.3.7. CLASS
The CLASS property [RFC5545] (Section 3.8.1.3) in a VEVENT or VTODO
component converts to the "privacy" property [JSCALENDAR]
(Section 3.4.3) of the Event or Task object.
JSCalendar requires all recurrences of a calendar object to have the
same "privacy" property value, including recurrence instances for
which no base object is given. In contrast, iCalendar supports
setting different CLASS property values for recurrence overrides.
How to choose the effective CLASS property value for all recurrences
when converting to JSCalendar is implementation-specific. One option
is to choose the most restrictive classification in any recurrence of
a calendar object, where CONFIDENTIAL is the most restrictive, then
PRIVATE or an unknown classification, and PUBLIC or the absent CLASS
property is the least restrictive.
The CLASS property values convert as follows:
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+==============+=========+
| CLASS | privacy |
+==============+=========+
| PUBLIC | public |
+--------------+---------+
| PRIVATE | private |
+--------------+---------+
| CONFIDENTIAL | secret |
+--------------+---------+
Table 14: Values of
the CLASS property
Any other value MUST convert to the "private" value. Implementations
MAY preserve the original value in the iCalendar/properties property
(Section 5.1.1).
The following example illustrates how to convert the CLASS property:
--- iCalendar:
CLASS:PRIVATE
--- JSCalendar:
"privacy": "private"
Figure 31: Converting the CLASS property
2.3.8. COLOR
The COLOR property [RFC7986] (Section 5.9) in a VEVENT, VTODO, or
VCALENDAR component converts to the "color" property [JSCALENDAR]
(Section 3.2.12) of the Event, Task, or Group object.
Its value converts verbatim.
The following example illustrates how to convert the COLOR property
with a color name:
--- iCalendar:
COLOR:maroon
--- JSCalendar:
"color": "maroon"
Figure 32: Converting the COLOR property with color name
The following example illustrates how to convert the COLOR property
with a numeric RGB value:
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--- iCalendar:
COLOR:#ffa07a
--- JSCalendar:
"color": "#ffa07a"
Figure 33: Converting the COLOR property with numeric value
2.3.9. CONCEPT
The CONCEPT property [RFC9253] (Section 8.1) in a VEVENT, VTODO, or
VCALENDAR component converts to the "categories" property
[JSCALENDAR] (Section 3.2.11) of the Event, Task, or Group object.
The list of URI values converts to a set of URIs. Multiple
occurrences of the CONCEPT property in the same iCalendar component
convert to the same "categories" property in the JSCalendar object.
The following example illustrates how to convert the CONCEPT
property:
--- iCalendar:
CONCEPT:https://example.com/event-types/arts/music
CONCEPT:https://example.com/event-types/arts/literature
--- JSCalendar:
"categories": {
"https://example.com/event-types/arts/music": true,
"https://example.com/event-types/arts/literature": true
}
Figure 34: Converting the CONCEPT property
2.3.10. CONFERENCE
The CONFERENCE property [RFC7986] (Section 5.11) in a VEVENT or VTODO
component converts to a VirtualLocation object [JSCALENDAR]
(Section 3.2.7). The converted object is set in the Event or Task
object's "virtualLocations" property. The property value converts to
the VirtualLocation object's "uri" property.
The key of the VirtualLocation object MUST be the value of the JSID
parameter (Section 4.2.1), if set. If no JSID parameter is set, then
the key MAY be the UUIDv5 generated from the property value (see
Section 2.1.3). When converting to iCalendar, implementations MAY
omit setting the JSID parameter if the key matches the UUIDv5 of the
CONFERENCE property value and the key is not part of a JSON pointer
in any JSPTR parameter value.
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The property value converts to the VirtualLocation object's "uri"
property.
Its parameters convert as follows:
+=====================+=====================+
| iCalendar parameter | JSCalendar property |
+=====================+=====================+
| FEATURE | features |
+---------------------+---------------------+
| LABEL | name |
+---------------------+---------------------+
Table 15: Parameters of the CONFERENCE
property
These parameters are defined in [RFC7986]: FEATURE (Section 6.3),
LABEL (Section 6.4).
The following example illustrates how to convert the CONFERENCE
property:
--- iCalendar:
CONFERENCE;VALUE=URI;FEATURE=AUDIO,VIDEO;
LABEL="Web video chat, access code=76543"
:https://chat.example.com/audio?id=123456
--- JSCalendar:
"virtualLocations": {
"67e4a1e9-cffc-5bd4-9602-1a5dfc8e1626": {
"@type": "VirtualLocation",
"name": "Web video chat, access code=76543",
"uri": "https://chat.example.com/audio?id=123456",
"features": {
"audio": true,
"video": true
}
}
}
Figure 35: Converting the CONFERENCE property
2.3.11. COORDINATES
The COORDINATES property [JSCAL-EXT] (Section 4.1) in a VLOCATION
component converts to the "coordinates" property [JSCALENDAR]
(Section 3.2.5) of the Location object.
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The following example illustrates how to convert the COORDINATES
property:
--- iCalendar:
BEGIN:VEVENT
BEGIN:VLOCATION
COORDINATES;VALUE=URI:geo:48.198634,16.371648;crs=wgs84;u=40
...
--- JSCalendar:
"locations": {
"B995322D-2C00-4DE0-8958-DB6687CF3DB3": {
"@type": "Location",
"coordinates": "geo:48.198634,16.371648;crs=wgs84;u=40",
"...": ""
}
}
Figure 36: Converting the COORDINATES property
2.3.12. CREATED
The CREATED property [RFC5545] (Section 3.8.7.1) in a VEVENT, VTODO,
or VCALENDAR component converts to the "created" property
[JSCALENDAR] (Section 3.1.5) of the Event, Task, or Group object.
The following example illustrates how to convert the CREATED
property:
--- iCalendar:
CREATED:20240329T133000Z
--- JSCalendar:
"created": "2024-03-29T13:30:00Z"
Figure 37: Converting the CREATED property
2.3.13. DESCRIPTION
The DESCRIPTION property [RFC5545] (Section 3.8.1.5) in a VEVENT,
VTODO, VCALENDAR, or PARTICIPANT component converts to the
"description" property [JSCALENDAR] (Section 3.2.2) of the Event,
Task, Group, or Participant object, unless its DERIVED parameter
value is TRUE.
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If the DERIVED parameter value is TRUE, then the property does not
convert to the "description" property. Instead, a non-derived
STYLED-DESCRIPTION property is expected to contain the description.
Implementations MAY preserve the property in the "iCalendar" property
(Section 5.1.1).
The following example illustrates how to convert the DESCRIPTION
property:
--- iCalendar:
DESCRIPTION:Pancakes are delicious\; they are fluffy and sweet.
--- JSCalendar:
"description": "Pancakes are delicious; they are fluffy and sweet."
Figure 38: Converting the DESCRIPTION property
2.3.14. DTEND
The DTEND property [RFC5545] (Section 3.8.2.2) in a VEVENT component
converts to the "duration" property [JSCALENDAR] (Section 4.1.2) of
the Event object.
If the value type of the DTEND property is DATE, then the duration is
the number of days or weeks between the DTSTART and DTEND property
values. If the value type is DATE-TIME, then the duration is the
timespan between the DTSTART and DTEND property values when converted
to UTC time.
If the timezone identifier (Section 2.1.4) of the DTEND property
differs from that of the DTSTART property, then it converts to the
Event's "endTimeZone" property [JSCALENDAR] (Section 4.1.3).
Implementations MAY preserve the fact that the duration got
determined by the DTEND property. How to do this depends on the
timezone identifiers of the DTSTART and DTEND properties: If the time
zone identifiers are not equal, then the presence of the
"endTimeZone" property implies that it converted from the DTEND
property. If the time zone identifiers are equal, then
implementations MAY set the "iCalendar" property (Section 5.1.1) in
the Event object and there add an entry for the path "duration" in
the "convertedProperties" property. The value MUST be an
ICalProperty object with the "name" property set to "dtend".
The following example illustrates how to convert the DTEND property
with a different timezone than the DTSTART property:
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--- iCalendar:
DTSTART;TZID=Europe/Berlin:20241017T130000
DTEND;TZID=Asia/Bangkok:20241018T040000
--- JSCalendar:
"start": "2024-10-17T13:00:00",
"timeZone": "Europe/Berlin",
"duration": "PT10H",
"endTimeZone": "Asia/Bangkok"
Figure 39: Converting the DTEND property with different timezone
The following example illustrates how to convert the DTEND property
with the same timezone as the DTSTART property:
--- iCalendar:
DTSTART;TZID=Australia/Melbourne:20241002T130000
DTEND;TZID=Australia/Melbourne:20241002T140000
--- JSCalendar:
"start": "2024-10-02T13:00:00",
"timeZone": "Australia/Melbourne",
"duration": "PT1H",
"iCalendar": {
"@type": "ICalComponent",
"name": "vevent",
"convertedProperties": {
"duration": {
"@type": "ICalProperty",
"name": "dtend"
}
}
}
Figure 40: Converting the DTEND property with same timezone
The following example illustrates how to convert the DTEND property
with value type DATE:
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--- iCalendar:
DTSTART;VALUE=DATE:20240102
DTEND;VALUE=DATE:20240107
--- JSCalendar:
"start": "2024-01-02T00:00:00",
"duration": "P5D",
"showWithoutTime": true,
"iCalendar": {
"@type": "ICalComponent",
"name": "vevent",
"convertedProperties": {
"duration": {
"@type": "ICalProperty",
"name": "dtend"
}
}
}
Figure 41: Converting the DTEND property with value type DATE
2.3.15. DTSTAMP
The DTSTAMP property [RFC5545] (Section 3.8.7.2) in a VEVENT or VTODO
component converts to the "updated" property [JSCALENDAR]
(Section 3.1.6) of the Event or Task object.
The following example illustrates how to convert the DTSTAMP
property:
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--- iCalendar:
BEGIN:VCALENDAR
METHOD:REPLY
BEGIN:VEVENT
DTSTAMP:20240304T132000Z
...
--- JSCalendar:
{
"@type": "Group",
"entries": [
{
"@type": "Event",
"method": "reply",
"updated": "2024-03-04T13:20:00Z",
"...": ""
}
],
"...": ""
}
Figure 42: Converting the DTSTAMP property in a VEVENT component
2.3.16. DTSTART
The DTSTART property [RFC5545] (Section 3.8.2.4) in a VEVENT or VTODO
component converts to the Event or Task object's "start" property
(Sections 4.1.1 and 4.2.2 of [JSCALENDAR]).
See Section 2.1.5 how to convert DATE and DATE-TIME values.
For VEVENT and VTODO components, the timezone identifier
(Section 2.1.4) of the DTSTART property converts to the Event or Task
object's "timeZone" property [JSCALENDAR] (Section 3.6.1). In
addition, if the value type of the DTSTART property is DATE, then the
value of the "showWithoutTime" property [JSCALENDAR] (Section 3.2.4)
is "true".
The following example illustrates how to convert the DTSTART property
with a TZID parameter:
--- iCalendar:
DTSTART;TZID=Europe/Berlin:20240921T105302
--- JSCalendar:
"start": "2024-09-21T10:53:02",
"timeZone": "Europe/Berlin",
"showWithoutTime": false
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Figure 43: Converting the DTSTART property with TZID parameter
The following example illustrates how to convert the DTSTART property
with a UTC time:
--- iCalendar:
DTSTART:20240921T105302Z
--- JSCalendar:
"start": "2024-09-21T10:53:02",
"timeZone": "Etc/UTC",
"showWithoutTime": false
Figure 44: Converting the DTSTART property with UTC time
The following example illustrates how to convert the DTSTART property
with a floating time:
--- iCalendar:
DTSTART:20240921T105302
--- JSCalendar:
"start": "2024-09-21T10:53:02",
"showWithoutTime": false
Figure 45: Converting the DTSTART property with floating time
The following example illustrates how to convert the DTSTART property
with value type DATE:
--- iCalendar:
DTSTART;VALUE=DATE:20240921
--- JSCalendar:
"start": "2024-09-21T00:00:00",
"showWithoutTime": true
Figure 46: Converting the DTSTART property with value type DATE
2.3.17. DUE
The DUE property [RFC5545] (Section 3.8.2.3) in a VTODO component
converts to the "due" property [JSCALENDAR] (Section 4.2.1) of the
Task object.
See Section 2.1.5 how to convert DATE and DATE-TIME values.
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If the VTODO component does not contain a DTSTART property, then the
timezone identifier (Section 2.1.4) of the DUE property converts to
the Task object's "timeZone" property [JSCALENDAR] (Section 3.6.1).
If it contains both the DUE and DTSTART properties and the timezone
identifier of the DUE property differs from that of the DTSTART
property, then the "due" date-time property value MUST be relative to
the time zone of DTSTART.
If the value type of the DUE property is DATE, then the value of the
"showWithoutTime" property [JSCALENDAR] (Section 3.2.4) is "true".
The following example illustrates how to convert the DUE property
with a TZID parameter:
--- iCalendar:
BEGIN:VTODO
DUE;TZID=Europe/Berlin:20240921T105302
...
--- JSCalendar:
"@type": "Task",
"due": "2024-09-21T10:53:02",
"timeZone": "Europe/Berlin",
"showWithoutTime": false
Figure 47: Converting the DUE property with TZID parameter
The following example illustrates how to convert the DUE property
with a UTC time:
--- iCalendar:
BEGIN:VTODO
DUE:20240921T105302Z
...
--- JSCalendar:
"@type": "Task",
"due": "2024-09-21T10:53:02",
"timeZone": "Etc/UTC",
"showWithoutTime": false
Figure 48: Converting the DUE property with UTC time
The following example illustrates how to convert the DUE property
with a floating time:
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--- iCalendar:
BEGIN:VTODO
DUE:20240921T105302
...
--- JSCalendar:
"@type": "Task",
"due": "2024-09-21T10:53:02",
"showWithoutTime": false
Figure 49: Converting the DUE property with floating time
The following example illustrates how to convert the DUE property
with value type DATE:
--- iCalendar:
BEGIN:VTODO
DUE;VALUE=DATE:20240921
...
--- JSCalendar:
"@type": "Task",
"due": "2024-09-21T00:00:00",
"showWithoutTime": true
Figure 50: Converting the DUE property with value type DATE
The following example illustrates how to convert the DUE property
with value type DATE in combination with a DTSTART property with
value type DATE:
--- iCalendar:
BEGIN:VTODO
DTSTART;VALUE=DATE:20250220
DUE;VALUE=DATE:20250221
...
--- JSCalendar:
"@type": "Task",
"start": "2025-02-20T00:00:00",
"due": "2025-02-21T00:00:00",
"showWithoutTime": true
Figure 51: Converting the DUE and DTSTART properties with value
type DATE
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2.3.18. DURATION
The DURATION property [RFC5545] (Section 3.8.2.5) in a VEVENT or
VTODO component converts to the "duration" property [JSCALENDAR]
(Section 4.1.2) of the Event or Task object.
The following example illustrates how to convert the DURATION
property:
--- iCalendar:
DURATION:PT1H
--- JSCalendar:
"duration": "PT1H"
Figure 52: Converting the DURATION
2.3.19. ESTIMATED-DURATION
The ESTIMATED-DURATION property [RFC10051] (Section 10.1) in a VTODO
component converts to the "estimatedDuration" property [JSCALENDAR]
(Section 4.2.3) of the Task object.
The following example illustrates how to convert the ESTIMATED-
DURATION property:
--- iCalendar:
BEGIN:VTODO
ESTIMATED-DURATION:P2D
...
--- JSCalendar:
"@type": "Task",
"estimatedDuration": "P2D"
Figure 53: Converting the ESTIMATED-DURATION
2.3.20. EXDATE
The EXDATE property [RFC5545] (Section 3.8.5.1) in a VEVENT or VTODO
component converts to a PatchObject value [JSCALENDAR]
(Section 1.5.9). The converted object is set in the Event or Task
object's "recurrenceOverrides" property.
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The property value converts to the key in the "recurrenceOverrides"
property value. See Section 2.1.5 how to convert DATE and DATE-TIME
values. The date-time MUST be relative to the timezone identified by
the Event or Task's "timeZone" property. The PatchObject value MUST
set the "excluded" member to "true" and MUST NOT set any other
property.
The following example illustrates how to convert the EXDATE property:
--- iCalendar:
DTSTART:20230101T130000Z
RRULE:FREQ=MONTHLY
EXDATE:20230801T130000Z
--- JSCalendar:
"start": "2023-01-01T13:00:00",
"timeZone": "Etc/UTC",
"recurrenceRule": {
"@type": "RecurrenceRule",
"frequency": "monthly"
},
"recurrenceOverrides": {
"2023-08-01T13:00:00": {
"excluded": true
}
}
Figure 54: Converting the EXDATE property
2.3.21. GEO
A GEO property with the DERIVED parameter value "TRUE" does not
convert to JSCalendar. For non-derived GEO properties, the following
rules apply:
The GEO property [RFC5545] (Section 3.8.1.6) in a VEVENT or VTODO
component converts to a Location object [JSCALENDAR] (Section 3.2.5).
If the VEVENT or VTODO component also contains the LOCATION property
(Section 2.3.25), then the GEO and LOCATION properties convert to the
same Location object. The converted object is set in the Event or
Task object's "locations" property.
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The key of the Location object MUST be the value of the JSID
parameter (Section 4.2.1), if set. If no JSID parameter is set, then
the key MAY be the UUIDv5 generated from the property value (see
Section 2.1.3). When converting to iCalendar, implementations MAY
omit setting the JSID parameter if the key matches the UUIDv5 of the
GEO property value and the key is not part of a JSON pointer in any
JSPTR parameter value.
The GEO property [RFC5545] (Section 3.8.1.6) in a VLOCATION component
converts to the "coordinates" property [JSCALENDAR] (Section 3.2.5)
of the Location object.
The pair of FLOAT values converts to a URI with the "geo" scheme
([RFC5870]). The first FLOAT value converts to the "coord-a" part of
the URI, the second FLOAT value to the "coord-b" part. A preceding
plus sign (+) of the FLOAT value MUST be omitted, a preceding minus
sign (-) MUST be preserved. The optional "coord-c" part of the URI
MUST be omitted.
Implementations MAY preserve the fact that the coordinates converted
from a GEO property by setting the JSON pointer path to the
"coordinates" property in the "iCalendar/convertedProperties"
property. If the GEO property converted from a VEVENT or VTODO
component, then the "iCalendar" property MUST be that of the Event or
Task object, for the VLOCATION component it MUST be the Location
object's "iCalendar" property.
The following example illustrates how to convert the GEO property in
a VEVENT component. The JSID parameter is set to simplify testing.
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--- iCalendar:
GEO;JSID=loc1:45.5;-93.3
--- JSCalendar:
"locations": {
"loc1": {
"@type": "Location",
"coordinates": "geo:45.5,-93.3"
}
},
"iCalendar": {
"@type": "ICalComponent",
"name": "vevent",
"convertedProperties": {
"locations/loc1/coordinates": {
"@type": "ICalProperty",
"name": "geo"
}
}
}
Figure 55: Converting the GEO property in a VEVENT
The following example illustrates how to convert the GEO and LOCATION
properties in a VEVENT component. The JSID parameters are set to
simplify testing.
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--- iCalendar:
LOCATION;JSID=loc1:Taj Mahal
GEO;JSID=loc1:27.175;78.041944
--- JSCalendar:
"locations": {
"loc1": {
"@type": "Location",
"name": "Taj Mahal",
"coordinates": "geo:27.175,78.041944",
"...": ""
}
},
"iCalendar": {
"@type": "ICalComponent",
"name": "vevent",
"convertedProperties": {
"locations/loc1/coordinates": {
"@type": "ICalProperty",
"name": "geo"
}
}
}
Figure 56: Converting the GEO and LOCATION properties in a VEVENT
The following example illustrates how to convert the GEO property in
a VLOCATION component:
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--- iCalendar:
BEGIN:VEVENT
BEGIN:VLOCATION
NAME:Eiffel Tower
GEO:48.858222;2.2945
...
--- JSCalendar:
"locations": {
"8FC58765-4559-49BC-8718-A5E46FC433B9": {
"@type": "Location",
"name": "Eiffel Tower",
"coordinates": "geo:48.858222,2.2945",
"iCalendar": {
"@type": "ICalComponent",
"name": "vlocation",
"convertedProperties": {
"coordinates": {
"@type": "ICalProperty",
"name": "geo"
}
},
"...": ""
}
}
}
Figure 57: Converting the GEO property in a VLOCATION
2.3.22. IMAGE
The IMAGE property [RFC7986] (Section 5.10) in a VEVENT, VTODO,
VLOCATION, PARTICIPANT, or VCALENDAR component converts to a Link
object [JSCALENDAR] (Section 1.5.11). The converted object is set in
the Event, Task, Location, Participant, or Group object's "links"
property. The "rel" property value is set to "icon".
The key of the Link object MUST be the value of the JSID parameter
(Section 4.2.1), if set. If no JSID parameter is set, then the key
MAY be the UUIDv5 generated from the property value (see
Section 2.1.3). When converting to iCalendar, implementations MAY
omit setting the JSID parameter if the key matches the UUIDv5 of the
IMAGE property value and the key is not part of a JSON pointer in any
JSPTR parameter value.
The IMAGE property value converts to the Link object's "href"
property. A value of type URI converts as-is. See Section 2.3.3 how
to convert a BINARY value.
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Its parameters convert as follows:
+=====================+=====================+
| iCalendar parameter | JSCalendar property |
+=====================+=====================+
| DISPLAY | display |
+---------------------+---------------------+
| FILENAME | title |
+---------------------+---------------------+
| FMTTYPE | contentType |
+---------------------+---------------------+
| SIZE | size |
+---------------------+---------------------+
Table 16: Parameters of the IMAGE property
These parameters are defined in [RFC7986]: DISPLAY (Section 6.1); and
in [RFC8607]: FILENAME (Section 4.2), SIZE (Section 4.1); and in
[RFC5545]: FMTTYPE (Section 3.2.8).
The following example illustrates how to convert the IMAGE property:
--- iCalendar:
IMAGE;VALUE=URI;DISPLAY=BADGE,THUMBNAIL;FILENAME=An image;
FMTTYPE=image/png:https://example.com/images/party.png
--- JSCalendar:
"links": {
"2c42ac17-1eaf-5a75-a216-aef848785d79": {
"@type": "Link",
"href": "https://example.com/images/party.png",
"rel": "icon",
"display": {
"badge": true,
"thumbnail": true
},
"contentType": "image/png",
"title": "An image"
}
}
Figure 58: Converting the IMAGE property
2.3.23. LAST-MODIFIED
The LAST-MODIFIED property [RFC5545] (Section 3.8.7.3) in a VCALENDAR
component converts to the "updated" property [JSCALENDAR]
(Section 3.1.6) of the Group object.
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The LAST-MODIFIED property [RFC5545] (Section 3.8.7.3) in a VEVENT or
VTODO component does _not_ convert to the "updated" property
[JSCALENDAR] (Section 3.1.6) of the Event or Task object.
Implementations MAY instead preserve the LAST-MODIFIED property in
the "iCalendar" property.
The following example illustrates how to convert the LAST-MODIFIED
property:
--- iCalendar:
BEGIN:VCALENDAR
LAST-MODIFIED:20240914T231257Z
...
--- JSCalendar:
"@type": "Group",
"updated": "2024-09-14T23:12:57Z"
Figure 59: Converting the IMAGE property
2.3.24. LINK
A LINK property [RFC9253] (Section 8.2) with value type URI in a
VEVENT, VTODO, PARTICIPANT, VLOCATION, or VCALENDAR component
converts to a Link object [JSCALENDAR] (Section 1.5.11). The
converted object is set in the Event, Task, Participant, Location, or
Group object's "links" property.
The key of the Link object MUST be the value of the JSID parameter
(Section 4.2.1), if set. If no JSID parameter is set, then the key
MAY be the UUIDv5 generated from the property value (see
Section 2.1.3). When converting to iCalendar, implementations MAY
omit setting the JSID parameter if the key matches the UUIDv5 of the
LINK property value and the key is not part of a JSON pointer in any
JSPTR parameter value.
The LINK property value converts to the Link object's "href"
property.
The LINK property parameters convert as follows:
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+=====================+=====================+
| iCalendar parameter | JSCalendar property |
+=====================+=====================+
| FMTTYPE | contentType |
+---------------------+---------------------+
| LABEL | title |
+---------------------+---------------------+
| LINKREL | rel |
+---------------------+---------------------+
Table 17: Parameters of the LINK property
These parameters are defined in [RFC5545]: FMTTYPE (Section 3.2.8);
and in [RFC7986]: LABEL (Section 6.4); and in [RFC9253]: LINKREL
(Section 6.1).
A LINK property with any other value type does not convert to a
standard JSCalendar element. Implementations MAY convert it to the
"iCalendar" property (Section 5.1.1).
The following example illustrates how to convert the LINK property:
--- iCalendar:
LINK;LINKREL="https://example.com/linkrel/source";LABEL=Venue;
VALUE=URI:https://example.com/events
--- JSCalendar:
"links": {
"63023b12-fcf4-53fa-841d-8c1684b9f80b": {
"@type": "Link",
"href": "https://example.com/events",
"title": "Venue",
"rel": "https://example.com/linkrel/source"
}
}
Figure 60: Converting the LINK property
2.3.25. LOCATION
The LOCATION property [RFC5545] (Section 3.8.1.7) in a VEVENT or
VTODO component converts to a Location object [JSCALENDAR]
(Section 3.2.5), unless its DERIVED parameter value is TRUE. The
converted object is set in the Event or Task's "locations" property.
The key of the Location object MUST be the value of the JSID
parameter (Section 4.2.1), if set. If no JSID parameter is set, then
the key MAY be the UUIDv5 generated from the property value (see
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Section 2.1.3). When converting to iCalendar, implementations MAY
omit setting the JSID parameter if the key matches the UUIDv5 of the
LOCATION property value and the key is not part of a JSON pointer in
any JSPTR parameter value.
The LOCATION property value converts to the Location object's "title"
property.
If the calendar component contains multiple VLOCATION components,
then the LOCATION property also converts to the Event or Task
object's "mainLocationId" property. If the LOCATION property does
not have the DERIVED parameter set to TRUE, then the "mainLocationId"
is set to the key of the Location object of the LOCATION property.
If instead the LOCATION property is derived and its property value
matches the NAME property value of a VLOCATION component, then the
"mainLocationId" is the identifier of the Location object of that
VLOCATION component.
The following example illustrates how to convert the LOCATION
property:
--- iCalendar:
LOCATION:Conference Room - F123\, Bldg. 002
--- JSCalendar:
"locations": {
"adde7a5b-2fb5-52aa-b760-595ea9edb80a": {
"@type": "Location",
"name": "Conference Room - F123, Bldg. 002",
"...": ""
}
}
Figure 61: Converting the LOCATION property
The following example illustrates how to convert the LOCATION
property and multiple VLOCATION components:
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--- iCalendar:
LOCATION;DERIVED=TRUE:Fred's Bar
BEGIN:VLOCATION
UID:12D2B3EC-AC84-4B70-9EB6-CFE6AD5830B0
NAME:Fred's Bar
LOCATION-TYPE:bar
...
END:VLOCATION
BEGIN:VLOCATION
UID:6B1C3968-38D2-46AF-B436-BF3F72D459D4
NAME:XYZ Parking
LOCATION-TYPE:parking
COORDINATES;VALUE=URI:geo:40.71427,-74.00597
...
END:VLOCATION
...
--- JSCalendar:
"locations": {
"12D2B3EC-AC84-4B70-9EB6-CFE6AD5830B0": {
"@type": "Location",
"name": "Fred's Bar",
"locationTypes": {
"bar": true
},
"...": ""
},
"6B1C3968-38D2-46AF-B436-BF3F72D459D4": {
"@type": "Location",
"name": "XYZ Parking",
"locationTypes": {
"parking": true
},
"coordinates": "geo:40.71427,-74.00597",
"...": ""
}
},
"mainLocationId": "12D2B3EC-AC84-4B70-9EB6-CFE6AD5830B0"
Figure 62: Converting the LOCATION property and multiple
VLOCATION components
2.3.26. LOCATION-TYPE
The LOCATION-TYPE property [RFC9073] (Section 6.1) in a VLOCATION
component converts to the "locationTypes" property [JSCALENDAR]
(Section 3.2.5) of the Location object.
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The list of location type values converts to a set of location types.
The values convert case-sensitively. All LOCATION-TYPE properties in
the same VLOCATION convert to the "locationTypes" property in the
Location object.
The following example illustrates how to convert the LOCATION-TYPE
property:
--- iCalendar:
BEGIN:VEVENT
BEGIN:VLOCATION
LOCATION-TYPE:hotel,restaurant
...
--- JSCalendar:
"locations": {
"0EA3F99A-835E-49CC-970C-8A4707A4C076": {
"@type": "Location",
"locationTypes": {
"hotel": true,
"restaurant": true
},
"...": ""
}
}
Figure 63: Converting the LOCATION property
2.3.27. METHOD
The METHOD property [RFC5545] (Section 3.7.2) in a VCALENDAR
component converts to the "method" property [JSCALENDAR]
(Section 3.1.8) of all Event or Task objects that are listed in the
Group object's "entries" property.
The property value converts in lowercase.
The following example illustrates how to convert the METHOD property:
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--- iCalendar:
BEGIN:VCALENDAR
METHOD:REQUEST
BEGIN:VEVENT
...
--- JSCalendar:
{
"@type": "Group",
"entries": [
{
"@type": "Event",
"method": "request",
"...": ""
}
],
"...": ""
}
Figure 64: Converting the METHOD property
2.3.28. NAME
The NAME property [RFC7986] (Section 5.1) in a VLOCATION component
converts to the Location [JSCALENDAR] (Section 3.2.5) object's "name"
property.
The NAME property [RFC7986] (Section 5.1) in a VCALENDAR component
converts to the "title" property [JSCALENDAR] (Section 3.2.1) of the
Group object. If the LANGUAGE parameter is set, then the parameter
value converts to the "locale" property [JSCALENDAR] (Section 3.2.9)
of the same object.
The following example illustrates how to convert the NAME property in
a VCALENDAR component:
--- iCalendar:
BEGIN:VCALENDAR
NAME;LANGUAGE=de:Feiertage Deutschland 2025
...
--- JSCalendar:
{
"@type": "Group",
"title": "Feiertage Deutschland 2025",
"locale": "de",
"...": ""
}
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Figure 65: Converting the NAME property in a VCALENDAR
The following example illustrates how to convert the NAME property in
a VLOCATION component:
--- iCalendar:
BEGIN:VEVENT
BEGIN:VLOCATION
NAME:Room B
...
END:VLOCATION
...
--- JSCalendar:
"locations": {
"8DE8404B-3BFA-443F-92B4-C678AD0F67DB": {
"@type": "Location",
"name": "Room B",
"iCalendar": {
"@type": "ICalComponent",
"name": "vlocation"
}
}
}
Figure 66: Converting the NAME property in a VLOCATION
2.3.29. ORGANIZER
The ORGANIZER property [RFC5545] (Section 3.8.4.3) in a VEVENT or
VTODO component converts to the "organizerCalendarAddress" property
[JSCALENDAR] (Section 3.4.4) of the Event or Task object.
It also converts to a Participant object in the "participants"
property [JSCALENDAR] (Section 3.4.6), if any of its parameters
convert to a Participant object property (see Table 18), or if none
of the ATTENDEE properties in the iCalendar component have the ROLE
parameter set to "OWNER". The ORGANIZER property value converts to
the Participant's "calendarAddress" property, the "owner" role is set
in Participant "roles" property.
The key of the Participant object MUST be the value of the JSID
parameter (Section 4.2.1), if set. If no JSID parameter is set, then
the key MAY be the UUIDv5 generated from the ORGANIZER property value
(see Section 2.1.3). When converting to iCalendar, implementations
MAY omit setting the JSID parameter if the key matches the UUIDv5 of
the ORGANIZER property value and the key is not part of a JSON
pointer in any JSPTR parameter value.
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The ORGANIZER property parameters convert to the Participant object
as follows:
+=====================+=====================+
| iCalendar parameter | JSCalendar property |
+=====================+=====================+
| CN | name |
+---------------------+---------------------+
| EMAIL | email |
+---------------------+---------------------+
| SENT-BY | sentBy |
+---------------------+---------------------+
Table 18: Parameters of the ORGANIZER
property
These parameters are defined in [RFC5545]: CN (Section 3.2.2), SENT-
BY (Section 3.2.18); and in [RFC7986]: EMAIL (Section 6.2).
In addition, the SENT-BY parameter also converts to the "sentBy"
property [JSCALENDAR] (Section 3.4.5) in the Event or Task object.
An ORGANIZER property, an ATTENDEE property, and a PARTICIPANT
component in the same iCalendar component all convert to the same
Participant object, if their converted "calendarAddress" property
values are equal. How to deal with conflicting property values is
implementation-specific.
The following example illustrates how to convert the ORGANIZER
property:
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--- iCalendar:
ORGANIZER:mailto:organizer@example.com
ATTENDEE;RSVP=TRUE:mailto:foo@example.com
--- JSCalendar:
"organizerCalendarAddress": "mailto:organizer@example.com",
"participants": {
"251d3e9f-d83f-534c-8c45-c2896c75670c": {
"@type": "Participant",
"calendarAddress": "mailto:organizer@example.com",
"roles": {
"owner": true
}
},
"59eb121c-e8f2-558a-9049-ef750a5976bd": {
"@type": "Participant",
"calendarAddress": "mailto:foo@example.com",
"expectReply": true,
"...": ""
}
}
Figure 67: Converting the ORGANIZER property
The following example illustrates how to convert the ORGANIZER
property together with an ATTENDEE property for the same calendar
address:
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--- iCalendar:
ORGANIZER;CN=Jane Doe:mailto:organizer@example.com
ATTENDEE;PARTSTAT=ACCEPTED;CN=Jane Doe:mailto:organizer@example.com
ATTENDEE;RSVP=TRUE;PARTSTAT=TENTATIVE:mailto:foo@example.com
--- JSCalendar:
"organizerCalendarAddress": "mailto:organizer@example.com",
"participants": {
"251d3e9f-d83f-534c-8c45-c2896c75670c": {
"@type": "Participant",
"calendarAddress": "mailto:organizer@example.com",
"name": "Jane Doe",
"participationStatus": "accepted",
"roles": {
"owner": true
}
},
"59eb121c-e8f2-558a-9049-ef750a5976bd": {
"@type": "Participant",
"calendarAddress": "mailto:foo@example.com",
"expectReply": true,
"participationStatus": "tentative",
"...": ""
}
}
Figure 68: Converting the ORGANIZER and related ATTENDEE property
The following example illustrates how to convert the ORGANIZER
property with a CN parameter if another participant has the OWNER
role:
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--- iCalendar:
ORGANIZER;CN=Jane Doe:mailto:organizer@example.com
ATTENDEE;ROLE=OWNER;RSVP=TRUE:mailto:foo@example.com
--- JSCalendar:
"organizerCalendarAddress": "mailto:organizer@example.com",
"participants": {
"251d3e9f-d83f-534c-8c45-c2896c75670c": {
"@type": "Participant",
"calendarAddress": "mailto:organizer@example.com",
"name": "Jane Doe",
"roles": {
"owner": true
}
},
"59eb121c-e8f2-558a-9049-ef750a5976bd": {
"@type": "Participant",
"calendarAddress": "mailto:foo@example.com",
"expectReply": true,
"roles": {
"owner": true
},
"...": ""
}
}
Figure 69: Converting the ORGANIZER property with CN parameter
and another owner
The following example illustrates how to convert the ORGANIZER
property if another participant has the OWNER role:
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--- iCalendar:
ORGANIZER:mailto:organizer@example.com
ATTENDEE;ROLE=OWNER;RSVP=TRUE:mailto:foo@example.com
--- JSCalendar:
"organizerCalendarAddress": "mailto:organizer@example.com",
"participants": {
"59eb121c-e8f2-558a-9049-ef750a5976bd": {
"@type": "Participant",
"calendarAddress": "mailto:foo@example.com",
"expectReply": true,
"roles": {
"owner": true
},
"...": ""
}
}
Figure 70: Converting the ORGANIZER property with another owner
2.3.30. PERCENT-COMPLETE
The PERCENT-COMPLETE property [RFC5545] (Section 3.8.1.8) in a VTODO
component converts to the "percentComplete" property [JSCALENDAR]
(Section 4.2.4) of the Task object.
The following example illustrates how to convert the PERCENT-COMPLETE
property:
--- iCalendar:
BEGIN:VCALENDAR
BEGIN:VTODO
PERCENT-COMPLETE:53
...
--- JSCalendar:
{
"@type": "Group",
"entries": [
{
"@type": "Task",
"percentComplete": 53,
"...": ""
}
],
"...": ""
}
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Figure 71: Converting the PERCENT-COMPLETE property in a VTODO
component
2.3.31. PRIORITY
The PRIORITY property [RFC5545] (Section 3.8.1.9) in a VEVENT or
VTODO component converts to the "priority" property [JSCALENDAR]
(Section 3.4.1) of the Event or Task object.
The following example illustrates how to convert the PRIORITY
property:
--- iCalendar:
PRIORITY:3
--- JSCalendar:
"priority": 3
Figure 72: Converting the PRIORITY property
2.3.32. PRODID
The PRODID property [RFC5545] (Section 3.7.3) in a VCALENDAR
component converts to the Group object's "prodId" property
[JSCALENDAR] (Section 3.1.4). Implementations MAY additionally
convert it also to the "prodId" property of all Event or Task objects
that are listed in the Group object's "entries" property.
The property value converts verbatim.
The following example illustrates how to convert the PRODID property:
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--- iCalendar:
BEGIN:VCALENDAR
PRODID:-//BAZ//bam//EN
BEGIN:VEVENT
...
--- JSCalendar:
{
"@type": "Group",
"prodId": "-//BAZ//bam//EN",
"entries": [
{
"@type": "Event",
"prodId": "-//BAZ//bam//EN",
"...": ""
}
],
"...": ""
}
Figure 73: Converting the PRODID property
2.3.33. RDATE
A RDATE property [RFC5545] (Section 3.8.5.2) in a VEVENT or VTODO
component converts to a PatchObject value [JSCALENDAR]
(Section 1.5.9). The converted object is set in the Event or Task
object's "recurrenceOverrides" property.
The property value converts to the key in the "recurrenceOverrides"
property value, for values of type PERIOD this only applies to the
period start. The date-time value MUST be relative to the timezone
identified by the Event or Task object's "timeZone" property
[JSCALENDAR] (Section 3.6.1), see Section 2.1.5 how to convert DATE
and DATE-TIME values. The duration of a PERIOD converts to the
PatchObject's "duration" property, otherwise the PatchObject value
MUST be an empty JSON object. Implementations MAY indicate that the
recurrence override was converted from an RDATE in the iCalendar
(Section 5.1.1) property.
The following example illustrates how to convert the RDATE property
with value type DATE-TIME:
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--- iCalendar:
DTSTART:20230101T130000Z
RRULE:FREQ=MONTHLY
RDATE:20230805T170000Z
--- JSCalendar:
"start": "2023-01-01T13:00:00",
"timeZone": "Etc/UTC",
"recurrenceRule": {
"@type": "RecurrenceRule",
"frequency": "monthly"
},
"recurrenceOverrides": {
"2023-08-05T17:00:00": {}
}
Figure 74: Converting the RDATE property
The following example illustrates how to convert the RDATE property
with value type PERIOD:
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--- iCalendar:
DTSTART:20230101T130000Z
DURATION:PT1H
RRULE:FREQ=MONTHLY
RDATE;VALUE=PERIOD:20231223T150000Z/PT2H
--- JSCalendar:
"start": "2023-01-01T13:00:00",
"duration": "PT1H",
"timeZone": "Etc/UTC",
"recurrenceRule": {
"@type": "RecurrenceRule",
"frequency": "monthly"
},
"recurrenceOverrides": {
"2023-12-23T15:00:00": {
"duration": "PT2H"
}
},
"iCalendar": {
"@type": "ICalComponent",
"convertedProperties": {
"recurrenceOverrides/2023-12-23T15:00:00": {
"@type": "ICalProperty",
"name": "rdate",
"valueType": "period"
}
},
"...": ""
}
Figure 75: Converting the RDATE property with value type PERIOD
2.3.34. RECURRENCE-ID
The RECURRENCE-ID property [RFC5545] (Section 3.8.4.4) in a VEVENT or
VTODO component converts to the "recurrenceId" property [JSCALENDAR]
(Section 3.3.1) of the Event or Task object. The timezone identifier
(Section 2.1.4) of the RECURRENCE-ID property converts to the
"recurrenceIdTimeZone" property [JSCALENDAR] (Section 3.3.2).
See Section 2.1.5 how to convert DATE and DATE-TIME values.
The RANGE parameter [RFC5545] (Section 3.2.13) does not convert to a
standard JSCalendar element. Implementations MAY preserve it in the
iCalendar (Section 5.1.1) property.
See Section 2.1.2 for further requirements and examples.
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2.3.35. RELATED-TO
The RELATED-TO property [RFC5545] (Section 3.8.4.5) in a VEVENT,
VTODO, or VALARM component converts to a Relation object [JSCALENDAR]
(Section 1.5.10). The converted object is set in the "relatedTo"
property of the Event or Task object [JSCALENDAR] (Section 3.1.3), or
the Alert object [JSCALENDAR] (Section 3.5.1).
The property value in a VEVENT or VTODO converts as-is to the id of
the Relation object in the "relatedTo" property. The property value
in a VALARM converts to the same value as the id of that Alert
object, which represents the VALARM component having that property
value set in the UID property. Any RELTYPE parameters convert to the
"relation" property in that Relation object. The parameter values
convert in lowercase.
The following example illustrates how to convert the RELATED-TO
property in a VEVENT component:
--- iCalendar:
BEGIN:VEVENT
RELATED-TO;RELTYPE=CHILD:4E05861C-A0C9-46AC-9A66-760FC1E0E167
RELATED-TO:4120A9B1-1133-4AC0-9185-C4C8396048ED
...
--- JSCalendar:
"relatedTo": {
"4E05861C-A0C9-46AC-9A66-760FC1E0E167": {
"@type": "Relation",
"relation": {
"child": true
}
},
"4120A9B1-1133-4AC0-9185-C4C8396048ED": {
"@type": "Relation"
}
}
Figure 76: Converting the RELATED-TO property in a VEVENT
The following example illustrates how to convert the RELATED-TO
property in a VALARM component:
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--- iCalendar:
BEGIN:VEVENT
...
BEGIN:VALARM
UID:8297C37D-BA2D-4476-91AE-C1EAA364F8E1
JSID:alert1
TRIGGER:-PT15M
DESCRIPTION:Event reminder
ACTION:DISPLAY
ACKNOWLEDGED:20210302T151514Z
END:VALARM
...
BEGIN:VALARM
UID:DE7B5C34-83FF-47FE-BE9E-FF41AE6DD097
JSID:alert2
TRIGGER;VALUE=DATE-TIME:20210302T152000Z
RELATED-TO;RELTYPE=SNOOZE:8297C37D-BA2D-4476-91AE-C1EAA364F8E1
DESCRIPTION:Event reminder
ACTION:DISPLAY
END:VALARM
...
--- JSCalendar:
"alerts": {
"alert1": {
"@type": "Alert",
"trigger": {
"@type": "OffsetTrigger",
"offset": "-PT15M"
},
"acknowledged": "2021-03-02T15:15:14Z",
"iCalendar": {
"@type": "ICalComponent",
"name": "valarm",
"properties": [
[
"description",
{},
"text",
"Event reminder"
],
[
"uid",
{},
"text",
"8297C37D-BA2D-4476-91AE-C1EAA364F8E1"
]
]
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},
"...": ""
},
"alert2": {
"@type": "Alert",
"trigger": {
"@type": "AbsoluteTrigger",
"when": "2021-03-02T15:20:00Z"
},
"relatedTo": {
"alert1": {
"@type": "Relation",
"relation": {
"snooze": true
}
}
},
"iCalendar": {
"@type": "ICalComponent",
"name": "valarm",
"properties": [
[
"description",
{},
"text",
"Event reminder"
],
[
"uid",
{},
"text",
"DE7B5C34-83FF-47FE-BE9E-FF41AE6DD097"
]
]
},
"...": ""
}
}
Figure 77: Converting the RELATED-TO property in a VALARM
2.3.36. RRULE
The RRULE property [RFC5545] (Section 3.8.5.3) in a VEVENT or VTODO
component converts to a RecurrenceRule object [JSCALENDAR]
(Section 3.3.3). The converted object is set in the Event or Task
object's "recurrenceRule" property.
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The RECUR value type converts to a RecurrenceRule object as follows:
+=======================+====================================+
| iCalendar RRULE field | JSCalendar RecurrenceRule property |
+=======================+====================================+
| FREQ | frequency |
+-----------------------+------------------------------------+
| UNTIL | until |
+-----------------------+------------------------------------+
| COUNT | count |
+-----------------------+------------------------------------+
| INTERVAL | interval |
+-----------------------+------------------------------------+
| BYSECOND | bySecond |
+-----------------------+------------------------------------+
| BYMINUTE | byMinute |
+-----------------------+------------------------------------+
| BYHOUR | byHour |
+-----------------------+------------------------------------+
| BYDAY | byDay |
+-----------------------+------------------------------------+
| BYMONTHDAY | byMonthDay |
+-----------------------+------------------------------------+
| BYYEARDAY | byYearDay |
+-----------------------+------------------------------------+
| BYWEEKNO | byWeekNo |
+-----------------------+------------------------------------+
| BYMONTH | byMonth |
+-----------------------+------------------------------------+
| BYSETPOS | bySetPosition |
+-----------------------+------------------------------------+
| WKST | firstDayOfWeek |
+-----------------------+------------------------------------+
| RSCALE [RFC7529] | rscale |
+-----------------------+------------------------------------+
| SKIP [RFC7529] | skip |
+-----------------------+------------------------------------+
Table 19: Converting the RECUR value type to a
RecurrenceRule object
The string values of the FREQ, WKST, RSCALE convert to lowercase.
The UNTIL part in a VEVENT or VTODO converts to a LocalDateTime value
relative to the timezone of the Event or Task object.
The following example illustrates how to convert the RRULE property:
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--- iCalendar:
DTSTART;TZID=Europe/Berlin:20240101T010000
RRULE:FREQ=YEARLY
;INTERVAL=2
;BYMONTH=1
;BYDAY=SU
;BYHOUR=8,9
;BYMINUTE=30
;UNTIL=20240930T120000Z
--- JSCalendar:
"recurrenceRule": {
"@type": "RecurrenceRule",
"frequency": "yearly",
"interval": 2,
"byMonth": [
"1"
],
"byDay": [
{
"@type": "NDay",
"day": "su"
}
],
"byHour": [
8,
9
],
"byMinute": [
30
],
"until": "2024-09-30T14:00:00"
},
"start": "2024-01-01T01:00:00",
"timeZone": "Europe/Berlin"
Figure 78: Example for converting the RRULE property
2.3.37. SEQUENCE
The SEQUENCE property [RFC5545] (Section 3.8.7.4) in a VEVENT or
VTODO component converts to the "sequence" property [JSCALENDAR]
(Section 3.1.7) of the Event or Task object.
The following example illustrates how to convert the SEQUENCE
property:
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--- iCalendar:
SEQUENCE:3
--- JSCalendar:
"sequence": 3
Figure 79: Example for converting the SEQUENCE property
2.3.38. SHOW-WITHOUT-TIME
The SHOW-WITHOUT-TIME property [JSCAL-EXT] (Section 4.2) in a VEVENT
or VTODO component converts to the "showWithoutTime" property
[JSCALENDAR] (Section 3.2.4) of the Event or Task object. As
outlined in the definition of the SHOW-WITHOUT-TIME property, the
property MUST be ignored if the temporal value type of the VEVENT or
VTODO component is DATE, or if the property value is "FALSE".
The following example illustrates how to convert the SHOW-WITHOUT-
TIME property:
--- iCalendar:
DTSTART;TZID=America/Chicago:20250521T080000
DURATION:PT12H
SHOW-WITHOUT-TIME;VALUE=BOOLEAN:TRUE
--- JSCalendar:
"start": "2025-05-21T08:00:00",
"timeZone": "America/Chicago",
"duration": "PT12H",
"showWithoutTime": true
Figure 80: Example for converting the SHOW-WITHOUT-TIME property
2.3.39. STATUS
The STATUS property [RFC5545] (Section 3.8.1.11) in a VEVENT
component converts to the "status" property [JSCALENDAR]
(Section 4.1.4) of the Event object. The STATUS property in a VTODO
component converts to the "progress" property [JSCALENDAR]
(Section 4.2.5) of the Task object.
The property value converts in lowercase.
The following example illustrates how to convert the STATUS property
in a VEVENT component:
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--- iCalendar:
STATUS:TENTATIVE
--- JSCalendar:
"status": "tentative"
Figure 81: Converting the STATUS property in a VEVENT
The following example illustrates how to convert the STATUS property
in a VTODO component:
--- iCalendar:
BEGIN:VTODO
STATUS:IN-PROCESS
...
--- JSCalendar:
{
"@type": "Task",
"progress": "in-process",
"...": ""
}
Figure 82: Converting the STATUS property in a VTODO
2.3.40. SOURCE
The SOURCE property [RFC7986] (Section 5.8) in a VCALENDAR component
converts to the "source" property [JSCALENDAR] (Section 4.3.2) of the
Group object.
The following example illustrates how to convert the SOURCE property:
--- iCalendar:
BEGIN:VCALENDAR
SOURCE;VALUE=URI:https://example.com/holidays.ics
...
--- JSCalendar:
{
"@type": "Group",
"source": "https://example.com/holidays.ics",
"...": ""
}
Figure 83: Example for converting the SOURCE property
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2.3.41. STYLED-DESCRIPTION
The STYLED-DESCRIPTION property [RFC9073] (Section 6.5) in a
PARTICIPANT, VEVENT or VTODO component converts to the "description"
property [JSCALENDAR] (Section 3.2.2) of the Participant, Event or
Task object under the following conditions:
* The property value type MUST be TEXT.
* The FMTTYPE parameter either MUST NOT be set, or its value MUST be
a media type [RFC6838] with top-level type "text".
* Its DERIVED parameter value MUST NOT be TRUE. If the value is
TRUE, then another property in the same component is expected to
contain the description.
If these conditions are not met, implementations MAY preserve the
property in the "iCalendar" property (Section 5.1.1).
Its FMTTYPE parameter [RFC5545] (Section 3.2.8) converts to the
"descriptionContentType" property [JSCALENDAR] (Section 3.2.3).
The following example illustrates how to convert the STYLED-
DESCRIPTION property:
--- iCalendar:
STYLED-DESCRIPTION;VALUE=TEXT;FMTTYPE=text/html:
hello\,world
--- JSCalendar:
"description": "hello,world",
"descriptionContentType": "text/html"
Figure 84: Converting the STYLED-DESCRIPTION property
2.3.42. SUMMARY
The SUMMARY property [RFC5545] (Section 3.8.1.12) in a VEVENT or
VTODO component converts to the "title" property [JSCALENDAR]
(Section 3.2.1) of the Event or Task object. If the LANGUAGE
parameter is set, then the parameter value converts to the "locale"
property [JSCALENDAR] (Section 3.2.9) of the same object.
The SUMMARY property [RFC5545] (Section 3.8.1.12) in a PARTICIPANT
component converts to the "name" property [JSCALENDAR]
(Section 3.4.6) of the Participant object.
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The following example illustrates how to convert the SUMMARY property
in a VEVENT component:
--- iCalendar:
SUMMARY:Birthday Party
--- JSCalendar:
"title": "Birthday Party"
Figure 85: Converting the SUMMARY property in a VEVENT
The following example illustrates how to convert the SUMMARY property
with a LANGUAGE parameter:
--- iCalendar:
SUMMARY;LANGUAGE=fr:Fête d'anniversaire
--- JSCalendar:
"title": "Fête d'anniversaire",
"locale": "fr"
Figure 86: Converting the SUMMARY property with LANGUAGE parameter
The following example illustrates how to convert the SUMMARY property
in a PARTICIPANT component:
--- iCalendar:
BEGIN:VEVENT
BEGIN:PARTICIPANT
SUMMARY:John
...
--- JSCalendar:
"participants": {
"858DA9AE-695B-43CD-BA4E-294C945356BC": {
"@type": "Participant",
"name": "John",
"...": ""
}
}
Figure 87: Converting the SUMMARY property in a PARTICIPANT
2.3.43. TRANSP
The TRANSP property [RFC5545] (Section 3.8.2.7) in a VEVENT or VTODO
component converts to the "freeBusyStatus" property [JSCALENDAR]
(Section 3.4.2) of the Event or Task object.
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Its values convert as follows:
+=============+================+
| TRANSP | freeBusyStatus |
+=============+================+
| OPAQUE | busy |
+-------------+----------------+
| TRANSPARENT | free |
+-------------+----------------+
Table 20: Values of the
TRANSP property
The following example illustrates how to convert the TRANSP property:
--- iCalendar:
TRANSP:TRANSPARENT
--- JSCalendar:
"freeBusyStatus": "free"
Figure 88: Converting the TRANSP property
2.3.44. TRIGGER
The TRIGGER property [RFC5545] (Section 3.8.6.3) in a VALARM
component converts to either an AbsoluteTrigger or OffsetTrigger
object. The converted object is set in the "trigger" property
[JSCALENDAR] (Section 3.5.1) of the Alert object.
A property of value type DURATION converts an OffsetTrigger object.
The property value converts to its "offset" property. A value of
type DATE-TIME converts to an AbsoluteTrigger object. The property
value converts to its "when" property.
Its parameters convert as follows:
+=====================+=====================+===================+
| iCalendar parameter | JSCalendar property | Note |
+=====================+=====================+===================+
| RELATED | relativeTo | If VALUE=DURATION |
+---------------------+---------------------+-------------------+
Table 21: Parameters of the TRIGGER property
These parameters are defined in [RFC5545]: RELATED (Section 3.2.14).
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The following example illustrates how to convert the TRIGGER property
to an OffsetTrigger object:
--- iCalendar:
BEGIN:VEVENT
...
BEGIN:VALARM
TRIGGER;RELATED=END:PT5M
...
--- JSCalendar:
"alerts": {
"2D3D674B-E3E4-4C63-BBF5-4582ED49BCB7": {
"@type": "Alert",
"trigger": {
"@type": "OffsetTrigger",
"offset": "PT5M",
"relativeTo": "end"
},
"...": ""
}
}
Figure 89: Converting the TRIGGER property to an OffsetTrigger
The following example illustrates how to convert the TRIGGER property
to an AbsoluteTrigger object:
--- iCalendar:
BEGIN:VEVENT
...
BEGIN:VALARM
TRIGGER;VALUE=DATE-TIME:20250302T010203Z
...
--- JSCalendar:
"alerts": {
"6AB751CF-515B-4925-9B8D-5AA2185F3E64": {
"@type": "Alert",
"trigger": {
"@type": "AbsoluteTrigger",
"when": "2025-03-02T01:02:03Z"
},
"...": ""
}
}
Figure 90: Converting the TRIGGER property to an AbsoluteTrigger
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2.3.45. UID
The UID property [RFC5545] (Section 3.8.4.7) in a VEVENT, VTODO, or
VCALENDAR component converts to the "uid" property [JSCALENDAR]
(Section 3.1.1) of the Event, Task, or Group object.
The following example illustrates how to convert the UID property:
--- iCalendar:
UID:5ACEA86F-40CF-47EE-9CCA-7C85588A589F
--- JSCalendar:
"uid": "5ACEA86F-40CF-47EE-9CCA-7C85588A589F"
Figure 91: Converting the UID property
2.3.46. URL
The URL property [RFC5545] (Section 3.8.4.6) in a VEVENT, VTODO,
PARTICIPANT, VLOCATION, or VCALENDAR component converts to a Link
object [JSCALENDAR] (Section 1.5.11). The converted object is set in
the Event, Task, Participant, Location, or Group object's "links"
property. The "rel" property value is set to "describedby".
The key of the Link object MUST be the value of the JSID parameter
(Section 4.2.1), if set. If no JSID parameter is set, then the key
MAY be the UUIDv5 generated from the property value (see
Section 2.1.3). When converting to iCalendar, implementations MAY
omit setting the JSID parameter if the key matches the UUIDv5 of the
URL property value and the key is not part of a JSON pointer in any
JSPTR parameter value.
The URL property value converts to the Link object's "href" property.
The following example illustrates how to convert the URL property:
--- iCalendar:
URL:https://example.com/myurl
--- JSCalendar:
"links": {
"6669391a-2c73-5b89-9cfe-7a6c95a855e3": {
"@type": "Link",
"href": "https://example.com/myurl",
"rel": "describedby"
}
}
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Figure 92: Converting the URL property
3. Converting JSCalendar to iCalendar
3.1. Alert
The Alert object [JSCALENDAR] (Section 3.5.1) converts to a VALARM
component (Section 2.2.2). Its properties convert as follows:
+=====================+====================+===============+
| JSCalendar property | iCalendar property | Section |
| | (or other) | |
+=====================+====================+===============+
| acknowledged | ACKNOWLEDGED | 2.3.1 |
+---------------------+--------------------+---------------+
| action | ACTION | 2.3.2 |
+---------------------+--------------------+---------------+
| relatedTo | RELATED-TO | 2.3.35, and |
| | | remarks below |
+---------------------+--------------------+---------------+
| trigger | TRIGGER | 2.3.44 |
+---------------------+--------------------+---------------+
Table 22: Properties of the Alert object
Remarks:
* The value of the RELATED-TO property is the UID property value of
that VALARM component, to which the related Alert object converts
to. Consequently, the UID property for such a VALARM MUST be set,
otherwise the UID property MAY be set.
Other properties MAY be converted to JSPROP properties
(Section 4.1.2) in the VALARM component.
3.2. Event and Task
The Event object [JSCALENDAR] (Section 2.1) converts to a VEVENT
component (Section 2.2.3), the Task object [JSCALENDAR] (Section 2.2)
converts to a VTODO component (Section 2.2.5).
In the iCalendar component, the value data types of the DTSTART, DUE
and RECURRENCE-ID properties all MUST be of the same form, either
DATE, or DATE WITH LOCAL TIME, or DATE WITH UTC TIME (see
Section 3.3.5 of [RFC5545]). It MUST be DATE if the
"showWithoutTime" property value is "true", the "timeZone" property
value is not set, and the time component is zero in the values of the
"start", "due", "duration", "estimatedDuration", "recurrenceId"
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properties, and the RecurrenceRule object's "until" property, and in
any key of the "recurrenceOverrides" property value. Otherwise, it
MAY be DATE WITH UTC TIME if the "timeZone" property value is "Etc/
UTC" and the "endTimeZone" property value is not set. It MUST be
DATE WITH LOCAL TIME in all other cases.
The following table defines how to convert properties that are common
to both the Event and Task object types. Table 24 and Table 25 later
in this section define how to convert properties specific to either
Event or Task objects.
+==========================+====================+===================+
| JSCalendar property | iCalendar property | Section |
| | (or other) | |
+==========================+====================+===================+
| alerts | VALARM (component) | 3.1 |
+--------------------------+--------------------+-------------------+
| categories | CONCEPT | 2.3.9 |
+--------------------------+--------------------+-------------------+
| color | COLOR | 2.3.8 |
+--------------------------+--------------------+-------------------+
| created | CREATED | 2.3.12 |
+--------------------------+--------------------+-------------------+
| description | DESCRIPTION, or | 2.3.13, |
| | STYLED-DESCRIPTION | 2.3.41, and |
| | | remarks below |
+--------------------------+--------------------+-------------------+
| descriptionContentType | FMTTYPE | 2.3.41, and |
| | (parameter) of | remarks below |
| | STYLED-DESCRIPTION | |
+--------------------------+--------------------+-------------------+
| freeBusyStatus | TRANSP | 2.3.43 |
+--------------------------+--------------------+-------------------+
| keywords | CATEGORIES | 2.3.6 |
+--------------------------+--------------------+-------------------+
| links | ATTACH, or other | 3.4 |
+--------------------------+--------------------+-------------------+
| locale | LANGUAGE | 2.3.42, |
| | (parameter) of | 2.3.13, |
| | SUMMARY property | 2.3.41 |
+--------------------------+--------------------+-------------------+
| locations | LOCATION, GEO, or | 3.5 |
| | VLOCATION | |
| | (component) | |
+--------------------------+--------------------+-------------------+
| mainLocationId | LOCATION | 3.5 |
+--------------------------+--------------------+-------------------+
| method | METHOD of | 2.3.27, and |
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| | iCalendar object | 3.3 |
+--------------------------+--------------------+-------------------+
| organizerCalendarAddress | ORGANIZER | 2.3.29 |
+--------------------------+--------------------+-------------------+
| participants | ATTENDEE, or | 3.6 |
| | PARTICIPANT | |
| | (component) | |
+--------------------------+--------------------+-------------------+
| priority | PRIORITY | 2.3.31 |
+--------------------------+--------------------+-------------------+
| privacy | CLASS | 2.3.7, and |
| | | remarks below |
+--------------------------+--------------------+-------------------+
| prodId | PRODID of | 2.3.32, and |
| | iCalendar object | 3.3 |
+--------------------------+--------------------+-------------------+
| recurrenceId | RECURRENCE-ID | 2.3.34 |
+--------------------------+--------------------+-------------------+
| recurrenceIdTimeZone | TZID (parameter) | 2.3.34 |
| | of RECURRENCE-ID | |
+--------------------------+--------------------+-------------------+
| recurrenceOverrides | RDATE, EXDATE or | 2.1.2, and |
| | recurrence | remarks below |
| | override component | |
+--------------------------+--------------------+-------------------+
| recurrenceRule | RRULE | 2.3.36 |
+--------------------------+--------------------+-------------------+
| relatedTo | RELATED-TO | 2.3.35 |
+--------------------------+--------------------+-------------------+
| sentBy | SENT-BY | 2.3.29 |
| | (parameter) of | |
| | ORGANIZER | |
+--------------------------+--------------------+-------------------+
| sequence | SEQUENCE | 2.3.37 |
+--------------------------+--------------------+-------------------+
| showWithoutTime | SHOW-WITHOUT-TIME | 2.3.38, and |
| | | remarks below |
+--------------------------+--------------------+-------------------+
| timeZone | TZID (parameter) | 2.3.16, |
| | of DTSTART and DUE | 2.3.17 |
+--------------------------+--------------------+-------------------+
| title | SUMMARY | 2.3.42 |
+--------------------------+--------------------+-------------------+
| uid | UID | 2.3.45 |
+--------------------------+--------------------+-------------------+
| updated | DTSTAMP, and LAST- | 2.3.15, |
| | MODIFIED | 2.3.23 |
+--------------------------+--------------------+-------------------+
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| virtualLocations | CONFERENCE | 2.3.10 |
+--------------------------+--------------------+-------------------+
Table 23: Properties of the Event and Task object
Remarks:
* The "descriptionContentType" property value determines if the
"description" property converts to the DESCRIPTION or STYLED-
DESCRIPTION property. A description of content type "text/plain"
converts to the DESCRIPTION property. Any other description
converts to the STYLED-DESCRIPTION property, in which case a plain
text version of the rich-text description MAY be set additionally
in the DESCRIPTION property, having its DERIVED parameter set to
"TRUE". How to derive plain text from rich-text is
implementation-specific.
* The "privacy" property converts to the CLASS property of the main
component and all recurrence overrides. If the property value is
"private" and the iCalendar/properties property (Section 5.1.1)
contains a CLASS property with an unknown value, then
implementations MAY convert that preserved property rather than
setting the PRIVATE classification. In any case they MUST NOT set
more than one CLASS property per calendar component.
* The entries in the "recurrenceOverrides" property convert
depending on the contents of the PatchObject value. A PatchObject
that sets the "excluded" member to "true" converts to an EXDATE
property for the date-time of that recurrence instance. An empty
PatchObject converts to an RDATE property. Any other PatchObject
converts to a recurrence override component in the embedding
VCALENDAR component.
* The "showWithoutTime" property only converts to the SHOW-WITHOUT-
TIME property if the value data type of the DTSTART or DUE
properties is of form DATE WITH UTC TIME or DATE WITH LOCAL TIME.
Properties specific to the Event object type convert to iCalendar
properties as follows:
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+=====================+===============================+=========+
| JSCalendar property | iCalendar property (or other) | Section |
+=====================+===============================+=========+
| duration | DURATION, or DTEND | 2.3.18, |
| | | 2.3.14 |
+---------------------+-------------------------------+---------+
| endTimeZone | TZID parameter of DTEND | 2.3.14, |
| | | 2.3.17 |
+---------------------+-------------------------------+---------+
| start | DTSTART | 2.3.16 |
+---------------------+-------------------------------+---------+
| status | STATUS | 2.3.39 |
+---------------------+-------------------------------+---------+
Table 24: Properties of the Event object
Properties specific to the Task object type convert to iCalendar
properties as follows:
+=====================+===============================+=========+
| JSCalendar property | iCalendar property (or other) | Section |
+=====================+===============================+=========+
| due | DUE | 2.3.17 |
+---------------------+-------------------------------+---------+
| estimatedDuration | ESTIMATED-DURATION | 2.3.19 |
+---------------------+-------------------------------+---------+
| percentComplete | PERCENT-COMPLETE | 2.3.30 |
+---------------------+-------------------------------+---------+
| progress | STATUS | 2.3.39 |
+---------------------+-------------------------------+---------+
| start | DTSTART | 2.3.16 |
+---------------------+-------------------------------+---------+
Table 25: Properties of the Task object
Other properties MAY be converted to JSPROP properties
(Section 4.1.2) in the VEVENT or VTODO component.
3.3. Group
The Group object [JSCALENDAR] (Section 2.3) converts to a VCALENDAR
component (Section 2.1.1). The Event and Task objects in its
"entries" property [JSCALENDAR] (Section 4.3.1) convert to VEVENT and
VTODO components, see Section 3.2. Its properties convert as
follows:
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+=============+=============================+===================+
| JSCalendar | iCalendar property (or | Section |
| property | other) | |
+=============+=============================+===================+
| categories | CONCEPT | 2.3.9 |
+-------------+-----------------------------+-------------------+
| color | COLOR | 2.3.8 |
+-------------+-----------------------------+-------------------+
| created | CREATED | 2.3.12 |
+-------------+-----------------------------+-------------------+
| description | DESCRIPTION, or STYLED- | 2.3.13, 2.3.41, |
| | DESCRIPTION | and remarks below |
+-------------+-----------------------------+-------------------+
| entries | VEVENT or VTODO (component) | 3.2, and remarks |
| | | below |
+-------------+-----------------------------+-------------------+
| keywords | CATEGORIES | 2.3.6 |
+-------------+-----------------------------+-------------------+
| links | ATTACH, or other | 3.4 |
+-------------+-----------------------------+-------------------+
| locale | LANGUAGE (parameter) of | 2.3.28, 2.3.13 |
| | either NAME, or DESCRIPTION | |
| | (in order of preference) | |
+-------------+-----------------------------+-------------------+
| prodId | PRODID | 2.3.32, and |
| | | remarks below |
+-------------+-----------------------------+-------------------+
| source | SOURCE | 2.3.40 |
+-------------+-----------------------------+-------------------+
| title | NAME | 2.3.28 |
+-------------+-----------------------------+-------------------+
| uid | UID | 2.3.45 |
+-------------+-----------------------------+-------------------+
| updated | LAST-MODIFIED | 2.3.23 |
+-------------+-----------------------------+-------------------+
Table 26: Properties of the Group object
Remarks:
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* The "descriptionContentType" property value determines if the
"description" property converts to the DESCRIPTION or STYLED-
DESCRIPTION property. A description of content type "text/plain"
converts to the DESCRIPTION property. Any other description
converts to the STYLED-DESCRIPTION property, in which case a plain
text version of the rich-text description MAY be set additionally
in the DESCRIPTION property, having its DERIVED parameter set to
"TRUE". How to derive plain text from rich-text is
implementation-specific.
* The "prodId" property value of the Group object is expected to be
equal to the "prodId" property value of all the Group entries.
They all convert to the same, single PRODID property in the
VCALENDAR component. How to convert unequal "prodId" property
values is implementation-specific.
* The "method" property value in all the Group entries is expected
to be equal. How to convert entries with unequal "method"
property values is implementation-specific.
Other properties MAY be converted to JSPROP properties
(Section 4.1.2) in the VCALENDAR component.
3.4. Link
The Link object [JSCALENDAR] (Section 1.5.11) in the "links" property
[JSCALENDAR] (Section 3.2.8) of an Event, Task, Group, Location, or
Participant object converts to either an ATTACH property
(Section 2.3.3) or an IMAGE property (Section 2.3.22), or a LINK
property (Section 2.3.24), or an URL property (Section 2.3.46).
Which iCalendar property to choose is implementation-specific. As a
guideline, stopping at the first matching criteria:
1. Choose ATTACH if the "rel" property value is "enclosure".
2. Choose IMAGE if the "rel" property value is "icon".
3. Choose URL if the "rel" property value is "describedby" and no
URL property is set in the iCalendar component.
4. Choose LINK otherwise.
The "href" property converts to the property value. The other Link
properties convert as follows:
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+=============+=====================+===========================+
| JSCalendar | iCalendar parameter | Section |
| property | (or other) | |
+=============+=====================+===========================+
| contentType | FMTTYPE | 2.3.3 |
+-------------+---------------------+---------------------------+
| display | DISPLAY | 2.3.22 |
+-------------+---------------------+---------------------------+
| rel | LINKREL, or none | Section 6.1 of [RFC9253], |
| | | and remarks below |
+-------------+---------------------+---------------------------+
| size | SIZE | 2.3.3 |
+-------------+---------------------+---------------------------+
| title | FILENAME or LABEL | 2.3.3, 2.3.24, and |
| | | remarks below |
+-------------+---------------------+---------------------------+
Table 27: Properties of the Link object
Remarks:
* The LINKREL parameter is not specified for the ATTACH, IMAGE and
URL properties. For interoperability, implementations SHOULD NOT
set the LINKREL parameter on these properties. Instead,
implementations SHOULD only set the LINKREL parameter on the LINK
property, or any future property that explicitly names the LINKREL
parameter in its Property Parameters definition. As an exception
to this rule, implementations MAY set the LINKREL parameter on
ATTACH or IMAGE if the iCalendar property value type is BINARY.
* The "title" property converts to the FILENAME parameter for the
ATTACH and IMAGE properties. It converts to the LABEL parameter
for the LINK and URL properties.
Other properties MAY be converted to JSPROP properties
(Section 4.1.2) in the same component to which the Link object
converts to as a property.
3.5. Location
The Location object [JSCALENDAR] (Section 3.2.5) converts to either a
LOCATION (Section 2.3.25) or GEO (Section 2.3.21) property, or it
converts to a VLOCATION component (Section 2.2.4). Which iCalendar
element to choose is implementation-specific. As a guideline:
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* If the "iCalendar" property on the Location object is set, or the
parent JSCalendar object contains an entry for that Location in
the "convertedProperties" property of its "iCalendar" property,
then convert the object back to the named iCalendar component or
property.
* Choose LOCATION if the key of the Location object in the
"locations" property matches the "mainLocationId" property
[JSCALENDAR] (Section 3.2.6), or if the "name" property is set and
the iCalendar component does not already contain a LOCATION
property. The "name" property converts to the LOCATION property
value.
* Choose the VLOCATION component otherwise.
Implementations MAY convert one of the Location objects to both a
VLOCATION component and the LOCATION and GEO properties of the
component that contains the VLOCATION component. In this case, the
DERIVED parameter MUST be set on the LOCATION and GEO properties with
value "TRUE".
The properties convert to a VLOCATION component as follows:
+=====================+===============================+=========+
| JSCalendar property | iCalendar property (or other) | Section |
+=====================+===============================+=========+
| coordinates | COORDINATES | 2.3.11, |
| | | 2.3.21 |
+---------------------+-------------------------------+---------+
| links | ATTACH, or other | 3.4 |
+---------------------+-------------------------------+---------+
| locationTypes | LOCATION-TYPE | 2.3.26 |
+---------------------+-------------------------------+---------+
| name | NAME | 2.3.28 |
+---------------------+-------------------------------+---------+
Table 28: Properties of the Location object
Other properties MAY be converted to JSPROP properties
(Section 4.1.2) in the VLOCATION component, or the component which
the Location converts to as a property.
3.6. Participant
The Participant object [JSCALENDAR] (Section 3.4.6) converts to an
ATTENDEE property (Section 2.3.4) and PARTICIPANT component
(Section 2.2.1), unless it is fully represented by the ORGANIZER
property (Section 2.3.29):
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* It if fully represented by the ORGANIZER property if its
"calendarAddress" property value matches the
"organizerCalendarAddress" property value, and it does not have
any role but the "owner" role set, and it only has properties set
that convert to ORGANIZER parameters (see Table 18).
* Otherwise, it converts to an ATTENDEE property if the
"calendarAddress" property is set. The "calendarAddress" converts
to the ATTENDEE property value.
* It converts to a PARTICIPANT component if any of the Participant
properties in Table 30 are set. If the Participant object also
converts to an ATTENDEE property, then the CALENDAR-ADDRESS
property value of the PARTICIPANT component MUST match the
ATTENDEE property value.
The following Participant properties convert to parameters of the
ATTENDEE property. How to convert these if the Participant
"calendarAddress" property is not set is implementation-specific.
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+=====================+=====================+===============+
| JSCalendar property | iCalendar parameter | Section |
| | (or other) | |
+=====================+=====================+===============+
| delegatedFrom | DELEGATED-FROM | 2.3.4 |
+---------------------+---------------------+---------------+
| delegatedTo | DELEGATED-TO | 2.3.4 |
+---------------------+---------------------+---------------+
| email | EMAIL | 2.3.4, and |
| | | remarks below |
+---------------------+---------------------+---------------+
| expectReply | RSVP | 2.3.4 |
+---------------------+---------------------+---------------+
| kind | CUTYPE | 2.3.4 |
+---------------------+---------------------+---------------+
| memberOf | MEMBER | 2.3.4 |
+---------------------+---------------------+---------------+
| name | CN | 2.3.4, and |
| | | remarks below |
+---------------------+---------------------+---------------+
| participationStatus | PARTSTAT | 2.3.4 |
+---------------------+---------------------+---------------+
| progress | PARTSTAT | 2.3.4, and |
| | | remarks below |
+---------------------+---------------------+---------------+
| roles | ROLE | 2.3.4, and |
| | | remarks below |
+---------------------+---------------------+---------------+
| sentBy | SENT-BY | 2.3.4, and |
| | | remarks below |
+---------------------+---------------------+---------------+
Table 29: Properties of the Participant object that
convert to the ATTENDEE property
Remarks:
* The "owner" role needs not convert to the ROLE parameter of the
ATTENDEE property if the Participant object converts to both the
ATTENDEE and ORGANIZER property.
* The "name", "email" and "sentBy" properties also convert to
parameters of the ORGANIZER property, if the Participant converts
to the ORGANIZER property.
* The "progress" property converts to the PARTSTAT parameter as
outlined in Table 13.
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The following Participant properties convert to the PARTICIPANT
component:
+========================+====================+===================+
| JSCalendar property | iCalendar property | Section |
| | (or other) | |
+========================+====================+===================+
| description | DESCRIPTION, or | 2.3.13, 2.3.41, |
| | STYLED-DESCRIPTION | and remarks below |
+------------------------+--------------------+-------------------+
| descriptionContentType | FMTTYPE | 2.3.41 |
| | (parameter) of | |
| | STYLED-DESCRIPTION | |
+------------------------+--------------------+-------------------+
| links | ATTACH, or other | 3.4 |
+------------------------+--------------------+-------------------+
| name | SUMMARY | 2.3.42 |
+------------------------+--------------------+-------------------+
| percentComplete | PERCENT-COMPLETE | 2.3.30 |
+------------------------+--------------------+-------------------+
Table 30: Properties of the Participant object that convert to
the PARTICIPANT component
Other properties MAY be converted to JSPROP properties
(Section 4.1.2) in the PARTICIPANT component, or the component which
the Participant converts to as a property.
3.7. VirtualLocation
The VirtualLocation object [JSCALENDAR] (Section 3.2.7) converts to a
CONFERENCE property (Section 2.3.10).
The "uri" property converts to the CONFERENCE property value.
The following properties convert to parameters of the CONFERENCE
property:
+=====================+================================+=========+
| JSCalendar property | iCalendar parameter (or other) | Section |
+=====================+================================+=========+
| features | FEATURE | 2.3.10 |
+---------------------+--------------------------------+---------+
| name | LABEL | 2.3.10 |
+---------------------+--------------------------------+---------+
Table 31: Properties of the VirtualLocation object
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4. Updates to iCalendar
4.1. New Properties
4.1.1. JSID
Property Name:
JSID
Purpose:
This property preserves the identifier of a JSCalendar object
value in iCalendar.
Value type:
TEXT; also see "Format Definition" below for value restrictions.
Property Parameters:
IANA and non-standard property parameters can be specified on this
property.
Conformance:
This property can be specified at most once in any calendar
component.
Description:
This property specifies the JSON object key of the JSCalendar
object to which an iCalendar component converts to. For example,
this property set in a VALARM component within a VEVENT component
defines the key of the Alert object in the Event object's "alerts"
property (see Figure 93).
The value of the JSID property MUST be a valid object key
according to the definition of the JSCalendar property to which
the component converts to.
Format Definition:
This property is defined by the following notation:
jsid-prop = "JSID" *(";" other-param) ":" TEXT CRLF
Example(s):
The following example illustrates how to convert the JSID property
set in a VALARM component.
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--- iCalendar:
BEGIN:VEVENT
...
BEGIN:VALARM
UID:52DFB000-3C49-4577-8003-3086001BD26A
JSID:myalert
...
END:VALARM
--- JSCalendar:
"@type": "Event",
"alerts": {
"myalert": {
"@type": "Alert",
"iCalendar": {
"@type": "ICalComponent",
"name": "valarm",
"properties": [
[
"uid",
{},
"text",
"52DFB000-3C49-4577-8003-3086001BD26A"
]
]
},
"...": ""
}
}
Figure 93: Converting the JSID property of a VALARM component
4.1.2. JSPROP
Property Name:
JSPROP
Purpose:
This property represents a JSCalendar property in iCalendar.
Value type:
TEXT; also see "Format Definition" below for value restrictions.
Property Parameters:
The JSPTR parameter (Section 4.2.2) MUST be specified on this
property. Other IANA and non-standard property parameters can be
specified on this property.
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Conformance:
This property can be specified multiple times in any calendar
component.
Description:
This property converts an arbitrary JSCalendar property from and
to iCalendar. The iCalendar property value is the JSON-encoded
value of the JSCalendar property, represented as a TEXT value.
The JSON value MUST NOT be the null value, and it SHOULD NOT
contain insignificant whitespace as defined in Section 2 of
[RFC8259]. The value of the JSPTR parameter points to the
JSCalendar property within the JSCalendar object and MUST NOT
start with the SOLIDUS (U+002F) character. The pointer MUST NOT
reference into an array.
All JSPROP properties in a calendar component together form a
PatchObject [JSCALENDAR] (Section 1.5.9): the JSPTR parameter of a
JSPROP property corresponds to a key in the PatchObject, the
property value corresponds to the JSON value for that key. When
converting from iCalendar to JSCalendar, the PatchObject MUST only
be applied after all other iCalendar elements of the component
have been converted. Only new properties are allowed to be set, a
JSON pointer in the PatchObject that points to an existing
property MUST be ignored.
Format Definition:
This property is defined by the following notation:
jsprop = "JSPROP" jsprop-param ":" TEXT CRLF
jsprop-param = *(
; The following are MANDATORY and MUST NOT
; occur more than once
( ";" jsptr-param )
;
; The following is OPTIONAL
; and MAY occur more than once.
;
(";" other-param)
;
)
Example(s):
The following example illustrates how to convert a JSPROP property
with a JSON boolean value
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--- iCalendar:
JSPROP;JSPTR="example.com:foo":true
--- JSCalendar:
"example.com:foo": true
Figure 94: Converting the JSPROP property with a JSON boolean
value
The following example illustrates how to convert a JSPROP property
with a JSON object value
--- iCalendar:
JSPROP;JSPTR="example.com:foo":{"bar":1234\,"baz":"bam"}
--- JSCalendar:
"example.com:foo": {
"bar": 1234,
"baz": "bam"
}
Figure 95: Converting the JSPROP property with a JSON object value
The following example illustrates how to convert a JSPROP property
that points to a property within a JSCalendar Alert. The JSON
pointer in the JSPTR parameter is relative to the Alert object.
--- iCalendar:
BEGIN:VEVENT
...
BEGIN:VALARM
JSPROP;JSPTR="example.com:foo":"bar"
...
END:VALARM
--- JSCalendar:
"@type": "Event",
"alerts": {
"DB7A8058-2212-46D9-87C2-867C7F65D625": {
"@type": "Alert",
"example.com:foo": "bar",
"...": ""
}
}
Figure 96: Converting the JSPROP property within a VALARM
component
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The following example illustrates how to convert a JSPROP property
that points to a property within a JSCalendar Link. The JSON
pointer in the JSPTR parameter is relative to the Event object
because the Link object converts to an iCalendar property. The
JSID parameter (Section 4.2.1) on the ATTACH property ensures that
the JSON path remains valid during conversion.
--- iCalendar:
BEGIN:VEVENT
...
ATTACH;JSID=mylink1:https://www.rfc-editor.org/rfc/rfc8984.html
JSPROP;JSPTR="links/mylink1/example.com:foo":"bar"
...
--- JSCalendar:
"@type": "Event",
"links": {
"mylink1": {
"@type": "Link",
"href": "https://www.rfc-editor.org/rfc/rfc8984.html",
"example.com:foo": "bar",
"...": ""
}
}
Figure 97: Converting the JSPROP property within a Link object
4.2. New Parameters
4.2.1. JSID
Parameter Name:
JSID
Format Definition:
jsid-param = "JSID" "=" param-value
Description:
This parameter specifies the JSON object key of the JSCalendar
object to which an iCalendar property converts to. For example,
this parameter set on an ATTACH property within a VEVENT component
defines the key of the Link object in the Event object's "links"
property (see below for an example).
The value of the JSID parameter MUST be a valid key according to
the definition of the JSCalendar property to which the property
that this parameter is set on converts to. Typically, this
requires the value to be a valid Id [JSCALENDAR] (Section 1.5.1).
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Example(s):
--- iCalendar:
ATTACH;JSID=mylink1:https://example.com
--- JSCalendar:
"links": {
"mylink1": {
"@type": "Link",
"href": "https://example.com"
}
}
Figure 98: Converting the JSID parameter on an ATTACH property
4.2.2. JSPTR
Parameter name:
JSPTR
Purpose:
To specify a pointer to a JSCalendar property.
Description:
This parameter is set on a JSPROP (Section 4.1.2) property. Its
value points to a JSCalendar property. The parameter has a single
value that MUST be a valid PatchObject key as defined in
Section 1.5.9 of [JSCALENDAR]. The parameter value MUST be
quoted.
Format definition:
jsptr-param = "JSPTR" "=" quoted-string
Example(s):
For further examples, see Section 4.1.2.
JSPROP;JSPTR="example.com:foo":"bar"
5. Updates to JSCalendar
5.1. New Properties
5.1.1. iCalendar
Name:
iCalendar
Context:
Any JSCalendar object
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Type:
ICalComponent (optional)
Description
This property contains information about iCalendar data that got
converted to this JSCalendar object. It allows for preserving the
name of iCalendar elements, such as a component's name, properties
and subcomponents. This specification defines the ICalComponent
object type for converting iCalendar components to a JSCalendar
object. Future specifications MAY define additional value types
for this property.
An ICalComponent object has the following properties:
@type: String This specifies the type of this object. This MUST
be "ICalComponent", if set.
name: String (mandatory) This is the name of the iCalendar
component in lowercase.
components: *[][] (optional) This contains subcomponents of the
iCalendar component which did not convert to standard
JSCalendar elements. The value MUST be a list of iCalendar
components formatted in jCal as defined in Section 3.3 of
[RFC7265].
convertedProperties: String[ICalProperty] (optional) This
contains conversion-related information about the component's
properties that got partially or fully converted to JSCalendar.
Each key defines the path to a JSCalendar element. The value
for each key contains information about the iCalendar property
which converted to the JSCalendar element located at that key.
Unless otherwise defined for a specific iCalendar property, the
path points to the JSCalendar property that the iCalendar
property value converts to.
The key MUST be a valid key of a PatchObject as defined in
Section 1.5.9 of [JSCALENDAR]. The key MAY point to the key in
a nested object if the element at that key was converted from
an iCalendar property of the component for which the
"iCalendar" property is set. It MUST NOT point into nested
objects otherwise.
properties: *[][] (optional) This contains properties of the
iCalendar component which did not convert to standard
JSCalendar elements. The value MUST be a list of iCalendar
properties formatted in jCal as defined in Section 3.4 of
[RFC7265].
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An ICalProperty object has the following properties:
@type: String This specifies the type of this object. This MUST
be "ICalProperty", if set.
name: String (mandatory) This is the name of the iCalendar
property in lowercase.
valueType: String (optional) This is the name of the iCalendar
property value type in lowercase.
parameters: String[String|String[]] (optional) This contains
parameters of the iCalendar property. The value MUST comply
with iCalendar parameters formatted in jCal as defined in
Section 3.5 of [RFC7265].
The example in Figure 99 describes how to convert unknown iCalendar
elements to the "iCalendar" property. The X-FOO parameter set on the
SUMMARY property illustrates how to preserve an unknown iCalendar
parameter on a property that does convert to a standard JSCalendar
element. The X-BAR property and X-BAZ component illustrate how to
convert entirely unknown iCalendar elements.
--- iCalendar:
BEGIN:VEVENT
SUMMARY;X-FOO=bar:test
...
X-BAR:bam
...
BEGIN:X-BAZ
UID:507A08F9-81D8-4D16-9480-D6D75E977943
END:X-BAZ
...
--- JSCalendar:
{
"@type": "Event",
"title": "test",
"iCalendar": {
"@type": "ICalComponent",
"name": "vevent",
"convertedProperties": {
"title": {
"@type": "ICalProperty",
"name": "summary",
"parameters": {
"x-foo": "bar"
}
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}
},
"properties": [
[
"x-bar",
{},
"unknown",
"bam"
]
],
"components": [
[
"x-baz",
[
[
"uid",
{},
"text",
"507A08F9-81D8-4D16-9480-D6D75E977943"
]
],
[]
]
]
},
"...": ""
}
Figure 99: Converting unknown iCalendar elements to the
"iCalendar" property
6. Security Considerations
This specification defines how to convert between the JSCalendar and
iCalendar data formats. The security considerations for parsing and
formatting such data apply and are outlined in Section 6 of
[JSCALENDAR] and Section 7 of [RFC5545].
7. IANA Considerations
7.1. Changes to the "iCalendar Element Registries"
IANA will add the following entries to the "Properties" registry:
Property
JSID
Status
Current
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Reference
Section 4.1.1
Property
JSPROP
Status
Current
Reference
Section 4.1.2
IANA will add the following entries to the "Parameters" registry:
Parameter
JSID
Status
Current
Reference
Section 4.2.1
Parameter
JSPTR
Status
Current
Reference
Section 4.2.2
7.2. Changes to the "JSCalendar Registries"
IANA will add the following entries to the "JSCalendar Properties"
registry:
Property Name
components
Property Type
*[][]
Property Context
ICalComponent
Reference/Description
Section 5.1.1
Intended Usage
common
Since Version
2.0
Is Per-User
no
Change Controller
IETF
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Property Name
convertedProperties
Property Type
String[ICalProperty]
Property Context
ICalComponent
Reference/Description
Section 5.1.1
Intended Usage
common
Since Version
2.0
Is Per-User
no
Change Controller
IETF
Property Name
iCalendar
Property Type
ICalComponent
Property Context
Event, Location, Participant, Task
Reference/Description
Section 5.1.1
Intended Usage
common
Since Version
2.0
Is Per-User
no
Change Controller
IETF
Property Name
iCalendar
Property Type
ICalComponent
Property Context
Alert
Reference/Description
Section 5.1.1
Intended Usage
common
Since Version
2.0
Is Per-User
yes
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Change Controller
IETF
Property Name
name
Property Type
String
Property Context
ICalComponent, ICalProperty
Reference/Description
Section 5.1.1
Intended Usage
common
Since Version
2.0
Is Per-User
no
Change Controller
IETF
Property Name
parameters
Property Type
String[String|String[]]
Property Context
ICalProperty
Reference/Description
Section 5.1.1
Intended Usage
common
Since Version
2.0
Is Per-User
no
Change Controller
IETF
Property Name
properties
Property Type
*[][]
Property Context
ICalComponent
Reference/Description
Section 5.1.1
Intended Usage
common
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Since Version
2.0
Is Per-User
no
Change Controller
IETF
Property Name
valueType
Property Type
String
Property Context
ICalProperty
Reference/Description
Section 5.1.1
Intended Usage
common
Since Version
2.0
Is Per-User
no
Change Controller
IETF
IANA will update the following entry in the "JSCalendar Properties"
registry. The entry is identified by its Property Name. The values
listed for the other fields are appended to the comma-separated
values already set for these fields, unchanged fields are omitted.
Property Name
@type
Property Context
ICalComponent, ICalProperty
Reference/Description
Section 5.1.1
IANA will add the following entries to the "JSCalendar Types"
registry:
Type Name
ICalComponent
Reference/Description
Section 5.1.1
Intended Usage
common
Since Version
2.0
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Change Controller
IETF
Type Name
ICalProperty
Reference/Description
Section 5.1.1
Intended Usage
common
Since Version
2.0
Change Controller
IETF
8. References
8.1. Normative References
[JSCAL-EXT]
Stepanek, R., "iCalendar Format Extensions for
JSCalendar", Work in Progress, Internet-Draft, draft-ietf-
calext-icalendar-jscalendar-extensions-09, 29 October
2026, .
[JSCALENDAR]
Jenkins, N. and R. Stepanek, "JSCalendar 2.0: A JSON
Representation of Calendar Data", Work in Progress,
Internet-Draft, draft-ietf-calext-jscalendarbis-22, 4
October 2026, .
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
.
[RFC2397] Masinter, L., "The "data" URL scheme", RFC 2397,
DOI 10.17487/RFC2397, August 1998,
.
[RFC5234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", STD 68, RFC 5234,
DOI 10.17487/RFC5234, January 2008,
.
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[RFC5545] Desruisseaux, B., Ed., "Internet Calendaring and
Scheduling Core Object Specification (iCalendar)",
RFC 5545, DOI 10.17487/RFC5545, September 2009,
.
[RFC5870] Mayrhofer, A. and C. Spanring, "A Uniform Resource
Identifier for Geographic Locations ('geo' URI)",
RFC 5870, DOI 10.17487/RFC5870, June 2010,
.
[RFC6047] Melnikov, A., Ed., "iCalendar Message-Based
Interoperability Protocol (iMIP)", RFC 6047,
DOI 10.17487/RFC6047, December 2010,
.
[RFC6638] Daboo, C. and B. Desruisseaux, "Scheduling Extensions to
CalDAV", RFC 6638, DOI 10.17487/RFC6638, June 2012,
.
[RFC6838] Freed, N., Klensin, J., and T. Hansen, "Media Type
Specifications and Registration Procedures", BCP 13,
RFC 6838, DOI 10.17487/RFC6838, January 2013,
.
[RFC7265] Kewisch, P., Daboo, C., and M. Douglass, "jCal: The JSON
Format for iCalendar", RFC 7265, DOI 10.17487/RFC7265, May
2014, .
[RFC7529] Daboo, C. and G. Yakushev, "Non-Gregorian Recurrence Rules
in the Internet Calendaring and Scheduling Core Object
Specification (iCalendar)", RFC 7529,
DOI 10.17487/RFC7529, May 2015,
.
[RFC7953] Daboo, C. and M. Douglass, "Calendar Availability",
RFC 7953, DOI 10.17487/RFC7953, August 2016,
.
[RFC7986] Daboo, C., "New Properties for iCalendar", RFC 7986,
DOI 10.17487/RFC7986, October 2016,
.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, .
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[RFC8259] Bray, T., Ed., "The JavaScript Object Notation (JSON) Data
Interchange Format", STD 90, RFC 8259,
DOI 10.17487/RFC8259, December 2017,
.
[RFC9073] Douglass, M., "Event Publishing Extensions to iCalendar",
RFC 9073, DOI 10.17487/RFC9073, August 2021,
.
[RFC9074] Daboo, C. and K. Murchison, Ed., ""VALARM" Extensions for
iCalendar", RFC 9074, DOI 10.17487/RFC9074, August 2021,
.
[RFC9253] Douglass, M., "Support for iCalendar Relationships",
RFC 9253, DOI 10.17487/RFC9253, August 2022,
.
[RFC9562] Davis, K., Peabody, B., and P. Leach, "Universally Unique
IDentifiers (UUIDs)", RFC 9562, DOI 10.17487/RFC9562, May
2024, .
[RFC10051] Apthorp, A. and M. Douglass, "Task Extensions to
iCalendar", RFC 10051, DOI 10.17487/RFC10051, October
2026, .
[TZDB] "IANA Time Zone Database",
.
8.2. Informative References
[JMAP-CAL] Jenkins, N. and M. Douglass, "JSON Meta Application
Protocol (JMAP) for Calendars", Work in Progress,
Internet-Draft, draft-ietf-jmap-calendars-33, 13 October
2026, .
[RFC8607] Daboo, C., Quillaud, A., and K. Murchison, Ed.,
"Calendaring Extensions to WebDAV (CalDAV): Managed
Attachments", RFC 8607, DOI 10.17487/RFC8607, June 2019,
.
Appendix A. Discrepancies between iCalendar and JSCalendar
This section highlights iCalendar and JSCalendar elements for which
no conversion rule to a standard element is defined in this document.
This is informational and only complete at the time of publication of
this document.
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Implementations MAY choose to convert the following elements, for
example using the properties defined in Section 4 and Section 5, or
they might convert them to some vendor-specific extension properties.
Later RFC documents might also define new standard elements and
register them at IANA, either extending this list of inconvertible
elements, or rather reduce it by introducing a standard element to
convert to.
A.1. Unsupported iCalendar Elements
A.1.1. Components
The following components do not convert to a standard element in
JSCalendar:
* AVAILABLE [RFC7953], Section 3.1
* VAVAILABILITY [RFC7953], Section 3.1
* VFREEBUSY [RFC5545], Section 3.6.4
* VJOURNAL [RFC5545], Section 3.6.3
* VRESOURCE [RFC9073], Section 7.3
* VTIMEZONE [RFC5545], Section 3.6.5
* VSTATUS [RFC10051], Section 12.1
A.1.2. Properties by Component
The following components are defined to contain the listed
properties. But these properties do not convert to a standard
JSCalendar element.
A.1.2.1. PARTICIPANT [RFC9073], Section 7.1
* CATEGORIES [RFC5545], Section 3.8.1.2
* COMMENT [RFC5545], Section 3.8.1.4
* CONTACT [RFC5545], Section 3.8.4.2
* CREATED [RFC5545], Section 3.8.7.1
* LAST-MODIFIED [RFC5545], Section 3.8.7.3
* LINK [RFC9253], Section 8.2
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* LOCATION [RFC5545], Section 3.8.1.7
* PARTICIPANT-TYPE [RFC9073], Section 6.2
* PRIORITY [RFC5545], Section 3.8.1.9
* REASON [RFC10051], Section 10.2
* RELATED-TO [RFC5545], Section 3.8.4.5
* REQUEST-STATUS [RFC5545], Section 3.8.8.3
* RESOURCES [RFC5545], Section 3.8.1.10
* STATUS [RFC5545], Section 3.8.1.11
* STRUCTURED-DATA [RFC9074], Section 6.6
* UID [RFC5545], Section 3.8.4.7
A.1.2.2. VALARM [RFC5545], Section 3.6.6
* ATTACH [RFC5545], Section 3.8.1.1
* ATTENDEE [RFC5545], Section 3.8.4.1
* DESCRIPTION [RFC5545], Section 3.8.1.5
* DURATION [RFC5545], Section 3.8.2.5
* PROXIMITY [RFC9074], Section 8.1
* REPEAT [RFC5545], Section 3.8.6.2
* STYLED-DESCRIPTION [RFC9073], Section 6.5
* SUMMARY [RFC5545], Section 3.8.1.12
* UID [RFC5545], Section 3.8.4.7
A.1.2.3. VCALENDAR [RFC5545], Section 3.4
* CALSCALE [RFC5545], Section 3.7.1
* LINK [RFC9253], Section 8.2
* REFRESH-INTERVAL [RFC7986], Section 5.7
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* VERSION [RFC5545], Section 3.7.4
A.1.2.4. VEVENT [RFC5545], Section 3.6.1
* COMMENT [RFC5545], Section 3.8.1.4
* CONTACT [RFC5545], Section 3.8.4.2
* LINK [RFC9253], Section 8.2
* REFID [RFC9253], Section 8.3
* REQUEST-STATUS [RFC5545], Section 3.8.8.3
* RESOURCES [RFC5545], Section 3.8.1.10
* STRUCTURED-DATA [RFC9074], Section 6.6
A.1.2.5. VLOCATION [RFC9073], Section 7.2
* DESCRIPTION [RFC5545], Section 3.8.1.5
* LINK [RFC9253], Section 8.2
* UID [RFC5545], Section 3.8.4.7
* STRUCTURED-DATA [RFC9074], Section 6.6
* STYLED-DESCRIPTION [RFC9073], Section 6.5
A.1.2.6. VTODO [RFC5545], Section 3.6.2
* COMMENT [RFC5545], Section 3.8.1.4
* COMPLETED [RFC5545], Section 3.8.2.1
* CONTACT [RFC5545], Section 3.8.4.2
* LINK [RFC9253], Section 8.2
* REFID [RFC9253], Section 8.3
* REQUEST-STATUS [RFC5545], Section 3.8.8.3
* RESOURCES [RFC5545], Section 3.8.1.10
* STRUCTURED-DATA [RFC9074], Section 6.6
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* TASK-MODE [RFC10051], Section 10.4
A.1.3. Subcomponents by Component
The following components are defined to contain the listed
subcomponents. But these subcomponents do not convert to a standard
JSCalendar element.
A.1.3.1. PARTICIPANT [RFC9073], Section 7.1
* VLOCATION [RFC9073], Section 7.2
A.1.4. Properties by Value Type
The following properties convert to a standard JSCalendar element for
some other value type, but they do not for the listed value types.
A.1.4.1. RDATE [RFC5545], Section 3.8.5.2
* PERIOD [RFC5545], Section 3.3.9
A.1.5. Parameters by Property
The following properties are defined to contain the listed
parameters. But these parameters do not convert to a standard
JSCalendar element.
A.1.5.1. ATTACH [RFC5545], Section 3.8.1.1
* MANAGED-ID [RFC8607], Section 4.3
A.1.5.2. ATTENDEE [RFC5545], Section 3.8.4.1
* DIR [RFC5545], Section 3.2.6
* SCHEDULE-AGENT [RFC6638], Section 7.1
* SCHEDULE-FORCE-SEND [RFC6638], Section 7.2
* SCHEDULE-STATUS [RFC6638], Section 7.3
* SENT-BY [RFC5545], Section 3.2.18
* LANGUAGE [RFC5545], Section 3.2.10
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A.1.5.3. CATEGORIES [RFC5545], Section 3.8.1.2
* LANGUAGE [RFC5545], Section 3.2.10
A.1.5.4. CONFERENCE [RFC7986], Section 5.11
* LANGUAGE [RFC5545], Section 3.2.10
A.1.5.5. DESCRIPTION [RFC5545], Section 3.8.1.5
* ALTREP [RFC5545], Section 3.2.1
* LANGUAGE [RFC5545], Section 3.2.10
A.1.5.6. IMAGE [RFC7986], Section 5.10
* ALTREP [RFC5545], Section 3.2.1
* DISPLAY [RFC7986], Section 6.1 (if the parameter value contains
more than one "displayval").
A.1.5.7. LINK [RFC9253], Section 8.2
* LANGUAGE [RFC5545], Section 3.2.10
A.1.5.8. LOCATION [RFC5545], Section 3.8.1.7
* ALTREP [RFC5545], Section 3.2.1
* LANGUAGE [RFC5545], Section 3.2.10
A.1.5.9. NAME [RFC7986], Section 5.1
* ALTREP [RFC5545], Section 3.2.1
A.1.5.10. ORGANIZER [RFC5545], Section 3.8.4.3
* DIR [RFC5545], Section 3.2.6
* SENT-BY [RFC5545], Section 3.2.18
* LANGUAGE [RFC5545], Section 3.2.10
* SCHEDULE-AGENT [RFC6638], Section 7.1
* SCHEDULE-FORCE-SEND [RFC6638], Section 7.2
* SCHEDULE-STATUS [RFC6638], Section 7.3
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A.1.5.11. RECURRENCE-ID [RFC5545], Section 3.8.4.4
* RANGE [RFC5545], Section 3.2.13
A.1.5.12. RELATED-TO [RFC5545], Section 3.8.4.5
* GAP [RFC9253], Section 6.2
A.1.5.13. REQUEST-STATUS [RFC5545], Section 3.8.8.3
* LANGUAGE [RFC5545], Section 3.2.10
A.1.5.14. RESOURCES [RFC5545], Section 3.8.1.10
* ALTREP [RFC5545], Section 3.2.1
* LANGUAGE [RFC5545], Section 3.2.10
A.1.5.15. STYLED-DESCRIPTION [RFC9073], Section 6.5
* ALTREP [RFC5545], Section 3.2.1
* DERIVED [RFC9073], Section 5.3
* LANGUAGE [RFC5545], Section 3.2.10
A.1.5.16. SUMMARY [RFC5545], Section 3.8.1.12
* ALTREP [RFC5545], Section 3.2.1
A.1.5.17. TZNAME [RFC5545], Section 3.8.3.2
* LANGUAGE [RFC5545], Section 3.2.10
Author's Address
Robert Stepanek
Fastmail
PO Box 234
Collins St West
Melbourne VIC 8007
Australia
Email: rsto@fastmailteam.com
URI: https://www.fastmail.com
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