<pre>Internet Engineering Task Force (IETF)                        P. Kewisch
Request for Comments: 7265                                       Mozilla
Category: Standards Track                                       C. Daboo
ISSN: 2070-1721                                              Apple, Inc.
                                                             M. Douglass
                                                                     RPI
                                                                May 2014


                  <span class="h1">jCal: The JSON Format for iCalendar</span>

Abstract

   This specification defines "jCal", a JSON format for iCalendar data.
   The iCalendar data format is a text format for capturing and
   exchanging information normally stored within a calendaring and
   scheduling application, for example, tasks and events.  JSON is a
   lightweight, text-based, language-independent data interchange format
   commonly used in Internet applications.

Status of This Memo

   This is an Internet Standards Track document.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Further information on
   Internet Standards is available in <a href="./rfc5741#section-2">Section&nbsp;2 of RFC 5741</a>.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   <a href="http://www.rfc-editor.org/info/rfc7265">http://www.rfc-editor.org/info/rfc7265</a>.

Copyright Notice

   Copyright (c) 2014 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to <a href="https://www.rfc-editor.org/bcp/bcp78">BCP 78</a> and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (<a href="http://trustee.ietf.org/license-info">http://trustee.ietf.org/license-info</a>) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.



<span class="grey">Kewisch, et al.              Standards Track                    [Page 1]</span></pre>
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<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


Table of Contents

   <a href="#section-1">1</a>.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   <a href="#page-3">3</a>
   <a href="#section-2">2</a>.  Conventions Used in This Document . . . . . . . . . . . . . .   <a href="#page-4">4</a>
   <a href="#section-3">3</a>.  Converting from iCalendar to jCal . . . . . . . . . . . . . .   <a href="#page-4">4</a>
     <a href="#section-3.1">3.1</a>.  Pre-processing  . . . . . . . . . . . . . . . . . . . . .   <a href="#page-4">4</a>
     <a href="#section-3.2">3.2</a>.  iCalendar Stream and Objects (<a href="./rfc5545#section-3.4">RFC 5545, Section&nbsp;3.4</a>)  . .   <a href="#page-5">5</a>
     <a href="#section-3.3">3.3</a>.  Components (<a href="./rfc5545#section-3.6">RFC 5545, Section&nbsp;3.6</a>)  . . . . . . . . . . .   <a href="#page-6">6</a>
     <a href="#section-3.4">3.4</a>.  Properties (<a href="./rfc5545">RFC 5545</a>, Sections <a href="#section-3.7">3.7</a> and <a href="#section-3.8">3.8</a>) . . . . . . .   <a href="#page-6">6</a>
       <a href="#section-3.4.1">3.4.1</a>.  Special Cases for Properties  . . . . . . . . . . . .   <a href="#page-8">8</a>
         <a href="#section-3.4.1.1">3.4.1.1</a>.  GEO Property (<a href="./rfc5545#section-3.8.1.6">RFC 5545, Section&nbsp;3.8.1.6</a>)  . . . .   <a href="#page-8">8</a>
         3.4.1.2.  REQUEST-STATUS Property (<a href="./rfc5545#section-3.8.8.3">RFC 5545, Section&nbsp;</a>
                   <a href="#section-3.8.8.3">3.8.8.3</a>)  . . . . . . . . . . . . . . . . . . . .   <a href="#page-8">8</a>
     <a href="#section-3.5">3.5</a>.  Parameters (<a href="./rfc5545#section-3.2">RFC 5545, Section&nbsp;3.2</a>)  . . . . . . . . . . .   <a href="#page-9">9</a>
       <a href="#section-3.5.1">3.5.1</a>.  VALUE Parameter . . . . . . . . . . . . . . . . . . .  <a href="#page-10">10</a>
       <a href="#section-3.5.2">3.5.2</a>.  Multi-value Parameters  . . . . . . . . . . . . . . .  <a href="#page-11">11</a>
     <a href="#section-3.6">3.6</a>.  Values (<a href="./rfc5545#section-3.3">RFC 5545, Section&nbsp;3.3</a>)  . . . . . . . . . . . . .  <a href="#page-11">11</a>
       <a href="#section-3.6.1">3.6.1</a>.  Binary (<a href="./rfc5545#section-3.3.1">RFC 5545, Section&nbsp;3.3.1</a>)  . . . . . . . . . .  <a href="#page-12">12</a>
       <a href="#section-3.6.2">3.6.2</a>.  Boolean  (<a href="./rfc5545#section-3.3.2">RFC 5545, Section&nbsp;3.3.2</a>)  . . . . . . . . .  <a href="#page-12">12</a>
       <a href="#section-3.6.3">3.6.3</a>.  Calendar User Address (<a href="./rfc5545#section-3.3.3">RFC 5545, Section&nbsp;3.3.3</a>) . . .  <a href="#page-12">12</a>
       <a href="#section-3.6.4">3.6.4</a>.  Date (<a href="./rfc5545#section-3.3.4">RFC 5545, Section&nbsp;3.3.4</a>)  . . . . . . . . . . .  <a href="#page-12">12</a>
       <a href="#section-3.6.5">3.6.5</a>.  Date-Time (<a href="./rfc5545#section-3.3.5">RFC 5545, Section&nbsp;3.3.5</a>) . . . . . . . . .  <a href="#page-13">13</a>
       <a href="#section-3.6.6">3.6.6</a>.  Duration (<a href="./rfc5545#section-3.3.6">RFC 5545, Section&nbsp;3.3.6</a>)  . . . . . . . . .  <a href="#page-13">13</a>
       <a href="#section-3.6.7">3.6.7</a>.  Float (<a href="./rfc5545#section-3.3.7">RFC 5545, Section&nbsp;3.3.7</a>) . . . . . . . . . . .  <a href="#page-14">14</a>
       <a href="#section-3.6.8">3.6.8</a>.  Integer (<a href="./rfc5545#section-3.3.8">RFC 5545, Section&nbsp;3.3.8</a>) . . . . . . . . . .  <a href="#page-14">14</a>
       <a href="#section-3.6.9">3.6.9</a>.  Period of Time (<a href="./rfc5545#section-3.3.9">RFC 5545, Section&nbsp;3.3.9</a>)  . . . . . .  <a href="#page-14">14</a>
       <a href="#section-3.6.10">3.6.10</a>. Recurrence Rule (<a href="./rfc5545#section-3.3.10">RFC 5545, Section&nbsp;3.3.10</a>)  . . . . .  <a href="#page-15">15</a>
       <a href="#section-3.6.11">3.6.11</a>. Text (<a href="./rfc5545#section-3.3.11">RFC 5545, Section&nbsp;3.3.11</a>) . . . . . . . . . . .  <a href="#page-16">16</a>
       <a href="#section-3.6.12">3.6.12</a>. Time (<a href="./rfc5545#section-3.3.12">RFC 5545, Section&nbsp;3.3.12</a>) . . . . . . . . . . .  <a href="#page-16">16</a>
       <a href="#section-3.6.13">3.6.13</a>. URI (<a href="./rfc5545#section-3.3.13">RFC 5545, Section&nbsp;3.3.13</a>)  . . . . . . . . . . .  <a href="#page-17">17</a>
       <a href="#section-3.6.14">3.6.14</a>. UTC Offset (<a href="./rfc5545#section-3.3.14">RFC 5545, Section&nbsp;3.3.14</a>) . . . . . . . .  <a href="#page-17">17</a>
     <a href="#section-3.7">3.7</a>.  Extensions  . . . . . . . . . . . . . . . . . . . . . . .  <a href="#page-17">17</a>
   <a href="#section-4">4</a>.  Converting from jCal into iCalendar . . . . . . . . . . . . .  <a href="#page-17">17</a>
   <a href="#section-5">5</a>.  Handling Unrecognized Properties or Parameters  . . . . . . .  <a href="#page-18">18</a>
     <a href="#section-5.1">5.1</a>.  Converting iCalendar into jCal  . . . . . . . . . . . . .  <a href="#page-18">18</a>
     <a href="#section-5.2">5.2</a>.  Converting jCal into iCalendar  . . . . . . . . . . . . .  <a href="#page-19">19</a>
     <a href="#section-5.3">5.3</a>.  Examples  . . . . . . . . . . . . . . . . . . . . . . . .  <a href="#page-19">19</a>
   <a href="#section-6">6</a>.  Security Considerations . . . . . . . . . . . . . . . . . . .  <a href="#page-20">20</a>
   <a href="#section-7">7</a>.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  <a href="#page-21">21</a>
     <a href="#section-7.1">7.1</a>.  UNKNOWN iCalendar Value Data Type . . . . . . . . . . . .  <a href="#page-22">22</a>
   <a href="#section-8">8</a>.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .  <a href="#page-23">23</a>
   <a href="#section-9">9</a>.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  <a href="#page-23">23</a>
     <a href="#section-9.1">9.1</a>.  Normative References  . . . . . . . . . . . . . . . . . .  <a href="#page-23">23</a>
     <a href="#section-9.2">9.2</a>.  Informative References  . . . . . . . . . . . . . . . . .  <a href="#page-24">24</a>







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<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


   <a href="#appendix-A">Appendix A</a>.  ABNF Schema  . . . . . . . . . . . . . . . . . . . .  <a href="#page-25">25</a>
   <a href="#appendix-B">Appendix B</a>.  Examples . . . . . . . . . . . . . . . . . . . . . .  <a href="#page-27">27</a>
     <a href="#appendix-B.1">B.1</a>.  Example 1 . . . . . . . . . . . . . . . . . . . . . . . .  <a href="#page-27">27</a>
       <a href="#appendix-B.1.1">B.1.1</a>.  iCalendar Data  . . . . . . . . . . . . . . . . . . .  <a href="#page-27">27</a>
       <a href="#appendix-B.1.2">B.1.2</a>.  jCal Data . . . . . . . . . . . . . . . . . . . . . .  <a href="#page-27">27</a>
     <a href="#appendix-B.2">B.2</a>.  Example 2 . . . . . . . . . . . . . . . . . . . . . . . .  <a href="#page-28">28</a>
       <a href="#appendix-B.2.1">B.2.1</a>.  iCalendar Data  . . . . . . . . . . . . . . . . . . .  <a href="#page-28">28</a>
       <a href="#appendix-B.2.2">B.2.2</a>.  jCal Data . . . . . . . . . . . . . . . . . . . . . .  <a href="#page-29">29</a>

<span class="h2"><a class="selflink" id="section-1" href="#section-1">1</a>.  Introduction</span>

   The iCalendar data format [<a href="./rfc5545" title="&quot;Internet Calendaring and Scheduling Core Object Specification (iCalendar)&quot;">RFC5545</a>] is a widely deployed interchange
   format for calendaring and scheduling data.  While many applications
   and services consume and generate calendar data, iCalendar is a
   specialized format that requires its own parser/generator.  In
   contrast, JSON-based formats as defined in [<a href="./rfc7159" title="&quot;The JavaScript Object Notation (JSON) Data Interchange Format&quot;">RFC7159</a>] are the native
   format for JavaScript widgets and libraries, and it is appropriate to
   have a standard form of calendar data that is easier to work with
   than iCalendar.

   The purpose of this specification is to define "jCal", a JSON format
   for iCalendar data. jCal is defined as a straightforward mapping into
   JSON from iCalendar, so that iCalendar data can be converted to JSON,
   and then back to iCalendar, without losing any semantic meaning in
   the data.  Anyone creating jCal calendar data according to this
   specification will know that their data can be converted to a valid
   iCalendar representation as well.

   The key design considerations are essentially the same as those for
   [<a href="./rfc6321" title="&quot;xCal: The XML Format for iCalendar&quot;">RFC6321</a>], that is:

      Round-tripping (converting an iCalendar instance to jCal and back)
      will give the same semantic result as the starting point.  For
      example, all components, properties, and property parameters are
      guaranteed to be preserved.

      Ordering of elements and case of property and parameter names will
      not necessarily be preserved.

      The iCalendar data semantics are to be preserved, allowing a
      simple consumer to easily browse the data in jCal.  A full
      understanding of iCalendar is still required in order to modify
      and/or fully comprehend the calendar data.

      Extensions to the underlying iCalendar specification must not lead
      to requiring an update to jCal.





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<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


<span class="h2"><a class="selflink" id="section-2" href="#section-2">2</a>.  Conventions Used in This Document</span>

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [<a href="./rfc2119" title="&quot;Key words for use in RFCs to Indicate Requirement Levels&quot;">RFC2119</a>].  The
   underlying format used for jCal is JSON.  Consequently, the terms
   "object" and "array" as well as the four primitive types (strings,
   numbers, booleans, and null) are to be interpreted as described in
   <a href="./rfc7159#section-1">Section&nbsp;1 of [RFC7159]</a>.

   Some examples in this document contain "partial" JSON documents used
   for illustrative purposes.  In these examples, three periods "..."
   are used to indicate a portion of the document that has been removed
   for compactness.

<span class="h2"><a class="selflink" id="section-3" href="#section-3">3</a>.  Converting from iCalendar to jCal</span>

   This section describes how iCalendar data is converted to jCal using
   a simple mapping between the iCalendar data model and JSON elements.
   Aside from the formal description in this section, an informative
   ABNF is specified in <a href="./rfc5545#appendix-A">Appendix&nbsp;A.

   In [RFC5545]</a>, an iCalendar object comprises a set of "components",
   "properties", "parameters", and "values".  The top level of iCalendar
   data typically contains a stream of iCalendar objects, each of which
   can be considered a "component".  A "component" can contain other
   "components" or "properties".  A "property" has a "value" and a set
   of zero or more "parameters".  Each of these entities have a
   representation in jCal, defined in the following sections.  The
   representation of an iCalendar object in JSON will be named "jCal
   object" throughout this document.

<span class="h3"><a class="selflink" id="section-3.1" href="#section-3.1">3.1</a>.  Pre-processing</span>

   iCalendar uses a line-folding mechanism to limit lines of data to a
   maximum line length (typically 75 octets) to ensure the maximum
   likelihood of preserving data integrity as it is transported via
   various means (e.g., email) -- see <a href="./rfc5545#section-3.1">Section&nbsp;3.1 of [RFC5545]</a>.

   iCalendar data uses an "escape" character sequence for text values
   and property parameter values.  See Sections <a href="#section-3.1">3.1</a> and <a href="#section-3.3">3.3</a> of [<a href="./rfc5545" title="&quot;Internet Calendaring and Scheduling Core Object Specification (iCalendar)&quot;">RFC5545</a>]
   as well as [<a href="./rfc6868" title="&quot;Parameter Value Encoding in iCalendar and vCard&quot;">RFC6868</a>].

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



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<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


   When converting from iCalendar to jCal: First, iCalendar lines MUST
   be unfolded.  Afterwards, any iCalendar escaping MUST be unescaped.
   Finally, JSON escaping, as described in <a href="./rfc7159#section-7">Section&nbsp;7 of [RFC7159]</a>, MUST
   be applied.  The reverse order applies when converting from jCal to
   iCalendar, which is further described in <a href="#section-4">Section 4</a>.

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

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

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

   When base64 encoding is used, it MUST conform to <a href="./rfc4648#section-4">Section&nbsp;4 of
   [RFC4648]</a>, which is the base64 method used in [<a href="./rfc5545" title="&quot;Internet Calendaring and Scheduling Core Object Specification (iCalendar)&quot;">RFC5545</a>].

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

<span class="h3"><a class="selflink" id="section-3.2" href="#section-3.2">3.2</a>.  iCalendar Stream and Objects (<a href="./rfc5545#section-3.4">RFC 5545, Section&nbsp;3.4</a>)</span>

   At the top level of the iCalendar object model is an "iCalendar
   stream".  This stream encompasses multiple "iCalendar objects".  As
   the typical use case is transporting a single iCalendar object, there
   is no defined equivalent to an "iCalendar stream" in jCal.  To
   transport multiple jCal objects in a stream, a simple JSON array can
   be used.

   Example:

   ["vcalendar",
     [ /* Add jCal properties in place of this comment */ ],
     [ /* Add jCal components in place of this comment */ ]
   ]








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<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


<span class="h3"><a class="selflink" id="section-3.3" href="#section-3.3">3.3</a>.  Components (<a href="./rfc5545#section-3.6">RFC 5545, Section&nbsp;3.6</a>)</span>

   Each iCalendar component, delimited by "BEGIN" and "END", will be
   converted to a fixed-length array with three fields that have a
   specific structure:

   1.  A string with the name of the iCalendar component, but in
       lowercase.

   2.  An array of jCal properties as described in <a href="#section-3.4">Section 3.4</a>.

   3.  An array of jCal components, representing the sub-components of
       the component in question.

   This mapping applies to the top level iCalendar objects, as well as
   individual sub-components in the same way.  The iCalendar to jCal
   component mapping is valid for both current iCalendar components and
   any new iCalendar components added in the future.  Conversion is to
   be done in the same way.

   While the grouping of properties and sub-components does not retain
   the original order specified in the iCalendar data, the semantics of
   a component are preserved.

   Example:

   ["vevent",
     [ /* Add jCal properties in place of this comment */ ],
     [ /* Add jCal components in place of this comment */ ]
   ]

<span class="h3"><a class="selflink" id="section-3.4" href="#section-3.4">3.4</a>.  Properties (<a href="./rfc5545">RFC 5545</a>, Sections <a href="#section-3.7">3.7</a> and <a href="#section-3.8">3.8</a>)</span>

   iCalendar properties, whether they apply to the "VCALENDAR" object or
   to a component, are handled in a consistent way in the jCal format.

   In jCal, each individual iCalendar property MUST be represented by an
   array with three fixed elements, followed by one or more additional
   elements, depending on if the property is a multi-valued property as
   described in <a href="./rfc5545#section-3.1.2">Section&nbsp;3.1.2 of [RFC5545]</a>.











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<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


   The array consists of the following fixed elements:

   1.  The name of the property, as a lowercase string.  The iCalendar
       format specifies that property names are case insensitive and
       recommends that they be rendered in uppercase.  In jCal, they
       MUST be in lowercase.

   2.  An object containing the parameters as described in <a href="#section-3.5">Section 3.5</a>.
       If the property has no parameters, an empty object is used to
       represent that.

   3.  The type identifier string of the value, in lowercase.  Due to
       special casing of certain properties as described in
       <a href="#section-3.4.1">Section 3.4.1</a>, it is important that parsers check both the type
       identifier and the value data type and do not rely on assumptions
       based on the property name.

   The remaining elements of the array are used for one or more values
   of the property.  For single-valued properties, the array has exactly
   four elements; for multi-valued properties, as described in
   <a href="./rfc5545#section-3.1.2">Section&nbsp;3.1.2 of [RFC5545]</a>, each value is another element, and there
   can be any number of additional elements.

   In the following example, the "categories" property is multi-valued
   and has two values, while the summary property is single-valued:

   Example:

   ["vevent",
     [
       ["summary", {}, "text", "Meeting with Fred"],
       ["categories", {}, "text", "Meetings", "Work"]
       ...
     ],
     [ /* sub-components */ ]
   ]















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<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


<span class="h4"><a class="selflink" id="section-3.4.1" href="#section-3.4.1">3.4.1</a>.  Special Cases for Properties</span>

   This section describes some properties that have special handling
   when converting to jCal.

<span class="h5"><a class="selflink" id="section-3.4.1.1" href="#section-3.4.1.1">3.4.1.1</a>.  GEO Property (<a href="./rfc5545#section-3.8.1.6">RFC 5545, Section&nbsp;3.8.1.6</a>)</span>

   In iCalendar, the "GEO" property value is defined as a semicolon-
   separated list of two "FLOAT" values, the first representing latitude
   and the second longitude.

   In jCal, the value for the "geo" property value is represented as an
   array of two values.  The first value of the property represents the
   latitude; the second value represents the longitude.

   When converting from jCal to iCalendar, be careful to use a semicolon
   as the separator between the two values as required by [<a href="./rfc5545" title="&quot;Internet Calendaring and Scheduling Core Object Specification (iCalendar)&quot;">RFC5545</a>].

   When converting from jCal to iCalendar, the two values MUST be
   converted using a semicolon as the separator character.

   Example

   ["vevent",
     [
       ["geo", {}, "float", [ 37.386013, -122.082932 ] ]
       ...
     ],
     ...
   ]

<span class="h5"><a class="selflink" id="section-3.4.1.2" href="#section-3.4.1.2">3.4.1.2</a>.  REQUEST-STATUS Property (<a href="./rfc5545#section-3.8.8.3">RFC 5545, Section&nbsp;3.8.8.3</a>)</span>

   In iCalendar, the "REQUEST-STATUS" property value is defined as a
   semicolon-separated list of two or three "TEXT" values.  The first
   represents a code, the second a description, and the third any
   additional data.

   In jCal, the value for the "request-status" property value is
   represented as an array with two or three values.  The first array
   element corresponds to the code, the second element corresponds to
   the description, and the third element corresponds to the additional
   data.  Each value is represented using a string value.  If there is
   no additional data in the iCalendar value, the last element of the
   array SHOULD NOT be present.

   When converting from jCal to iCalendar, the two or three values MUST
   be converted using a semicolon as the separator character.



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<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


   iCalendar Example:

   BEGIN:VEVENT
   ...
   REQUEST-STATUS:2.0;Success
   REQUEST-STATUS:3.7;Invalid calendar user;ATTENDEE:
    mailto:jsmith@example.com
   ...
   END:VEVENT

   jCal Example:

   ["vevent":
     [
       ["request-status", {}, "text", ["2.0", "Success"] ],
       ["request-status", {}, "text",
          [
           "3.7",
           "Invalid calendar user",
           "ATTENDEE:mailto:jsmith@example.org"
          ]
       ],
       ...
     ],
     ...
   ]

<span class="h3"><a class="selflink" id="section-3.5" href="#section-3.5">3.5</a>.  Parameters (<a href="./rfc5545#section-3.2">RFC 5545, Section&nbsp;3.2</a>)</span>

   Property parameters are represented as a JSON object where each key-
   value pair represents the iCalendar parameter name and its value.
   The name of the parameter MUST be in lowercase; the original case of
   the parameter value MUST be preserved.  For example, the "PARTSTAT"
   property parameter is represented in jCal by the "partstat" key.  Any
   new iCalendar parameters added in the future will be converted in the
   same way.















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   Example:

   ["vevent":
     [
       ["attendee",
        {
          "partstat": "ACCEPTED",
          "rsvp": "TRUE",
          "role": "REQ-PARTICIPANT"
        },
        "cal-address",
        "mailto:jsmith@example.org"
       ],
       ["summary", {}, "text", "Meeting"],
       ...
     ],
     ...
   ]

<span class="h4"><a class="selflink" id="section-3.5.1" href="#section-3.5.1">3.5.1</a>.  VALUE Parameter</span>

   iCalendar defines a "VALUE" property parameter (<a href="./rfc5545#section-3.2.20">Section&nbsp;3.2.20 of
   [RFC5545]</a>).  This property parameter MUST NOT be added to the
   parameters object.  Instead, the value type is signaled through the
   type identifier in the third element of the array describing the
   property.  When converting a property from iCalendar to jCal, the
   value type is determined as follows:

   1.  If the property has a "VALUE" parameter, that parameter's value
       is used as the value type.

   2.  If the property has no "VALUE" parameter but has a default value
       type, the default value type is used.

   3.  If the property has no "VALUE" parameter and has no default value
       type, "unknown" is used.

   Converting from jCal into iCalendar is done as follows:

   1.  If the property's value type is "unknown", no "VALUE" parameter
       is included.

   2.  If the property's value type is the default type for that
       property, no "VALUE" parameter is included.

   3.  Otherwise, a "VALUE" parameter is included, and the value type is
       used as the parameter value.




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<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


   See <a href="#section-5">Section 5</a> for information on handling unknown value types.

<span class="h4"><a class="selflink" id="section-3.5.2" href="#section-3.5.2">3.5.2</a>.  Multi-value Parameters</span>

   In [<a href="./rfc5545" title="&quot;Internet Calendaring and Scheduling Core Object Specification (iCalendar)&quot;">RFC5545</a>], some parameters allow using a COMMA-separated list of
   values.  To ease processing in jCal, the value of such parameters
   MUST be represented in an array containing the separated values.  The
   array elements MUST be string values.  Single-value parameters can be
   represented using either a single string value or an array with one
   string element.  A jCal parser MUST be able to understand both value
   data types.  Examples of such parameters are the iCalendar
   "DELEGATED-FROM" and "DELEGATED-TO" parameters; more such parameters
   may be added in extensions.

   The iCalendar specification requires encapsulation between DQUOTE
   characters if a parameter value contains a colon, a semicolon, or a
   comma.  These extra DQUOTE characters do not belong to the actual
   parameter value, and hence are not included when the parameter is
   converted to jCal.

   Example 1:

   ["attendee",
    {
      "delegated-to": ["mailto:jdoe@example.org",
                       "mailto:jqpublic@example.org"]
    },
    "cal-address",
    "mailto:jsmith@example.org"
   ]

   Example 2:

   ["attendee",
    {
      "delegated-to": "mailto:jdoe@example.org"
    },
    "cal-address",
    "mailto:jsmith@example.org"
   ]

<span class="h3"><a class="selflink" id="section-3.6" href="#section-3.6">3.6</a>.  Values (<a href="./rfc5545#section-3.3">RFC 5545, Section&nbsp;3.3</a>)</span>

   The following subsections specify how iCalendar property value data
   types, which are defined in the subsections of <a href="./rfc5545#section-3.3">[RFC5545],
   Section&nbsp;3.3</a>, are represented in jCal.





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<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


<span class="h4"><a class="selflink" id="section-3.6.1" href="#section-3.6.1">3.6.1</a>.  Binary (<a href="./rfc5545#section-3.3.1">RFC 5545, Section&nbsp;3.3.1</a>)</span>

   Description:  iCalendar "BINARY" property values are represented by a
      property with the type identifier "binary".  The value element is
      a JSON string, encoded with base64 encoding as specified in
      <a href="./rfc4648#section-4">Section&nbsp;4 of [RFC4648]</a>.

   Example:

   ["attach", {}, "binary", "SGVsbG8gV29ybGQh"]

<span class="h4"><a class="selflink" id="section-3.6.2" href="#section-3.6.2">3.6.2</a>.  Boolean (<a href="./rfc5545#section-3.3.2">RFC 5545, Section&nbsp;3.3.2</a>)</span>

   Description:  iCalendar "BOOLEAN" property values are represented by
      a property with the type identifier "boolean".  The value is a
      JSON boolean value.

   Example:

   ["x-non-smoking", {}, "boolean", true]

<span class="h4"><a class="selflink" id="section-3.6.3" href="#section-3.6.3">3.6.3</a>.  Calendar User Address (<a href="./rfc5545#section-3.3.3">RFC 5545, Section&nbsp;3.3.3</a>)</span>

   Description:  iCalendar "CAL-ADDRESS" property values are represented
      by a property with the type identifier "cal-address".  The value
      is a JSON string with the URI as described in [<a href="./rfc3986" title="&quot;Uniform Resource Identifier (URI): Generic Syntax&quot;">RFC3986</a>].

   Example:

   ["attendee", {}, "cal-address", "mailto:kewisch@example.com"]

<span class="h4"><a class="selflink" id="section-3.6.4" href="#section-3.6.4">3.6.4</a>.  Date (<a href="./rfc5545#section-3.3.4">RFC 5545, Section&nbsp;3.3.4</a>)</span>

   Description:  iCalendar "DATE" property values are represented by a
      property with the type identifier "date".  The value elements are
      JSON strings with the same date value specified by [<a href="./rfc5545" title="&quot;Internet Calendaring and Scheduling Core Object Specification (iCalendar)&quot;">RFC5545</a>], but
      represented using the extended format of the complete
      representation specified in [<a href="#ref-ISO.8601.2004">ISO.8601.2004</a>], Section 4.1.2.2.
      Other variations, for example, representation with reduced
      accuracy, MUST NOT be used.

   ABNF Schema:

   ; year, month, and day rules are
   ; defined in [<a href="#ref-ISO.8601.2004">ISO.8601.2004</a>], Section 2.2.
   date = year "-" month "-" day ;YYYY-MM-DD





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<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


   Example:

   ["dtstart", {}, "date", "2011-05-17"]

<span class="h4"><a class="selflink" id="section-3.6.5" href="#section-3.6.5">3.6.5</a>.  Date-Time (<a href="./rfc5545#section-3.3.5">RFC 5545, Section&nbsp;3.3.5</a>)</span>

   Description:  iCalendar "DATE-TIME" property values are represented
      by a property with the type identifier "date-time".  The value
      elements are JSON strings with the same date value specified by
      [<a href="./rfc5545" title="&quot;Internet Calendaring and Scheduling Core Object Specification (iCalendar)&quot;">RFC5545</a>], but represented using the extended format of the
      complete representation specified in [<a href="#ref-ISO.8601.2004">ISO.8601.2004</a>],
      Section 4.3.2.  Other variations, for example, representation with
      reduced accuracy, MUST NOT be used.  The same restrictions apply
      with respect to leap seconds and time zone offsets as specified in
      <a href="./rfc5545#section-3.3.5">[RFC5545], Section&nbsp;3.3.5</a>.

   ABNF Schema:

   ; year, month, day, hour, minute, and second rules are
   ; defined in [<a href="#ref-ISO.8601.2004">ISO.8601.2004</a>], Section 2.2.
   ; The zone identifier is described in [<a href="#ref-ISO.8601.2004">ISO.8601.2004</a>], Section 4.3.2.
   date-complete = year "-" month "-" day ;YYYY-MM-DD
   time-complete =  hour ":" minute ":" second [zone] ; HH:MM:SS
   datetime = date-complete "T" time-complete

   Examples:

   ["dtstart", {}, "date-time", "2012-10-17T12:00:00"],
   ["dtstamp", {}, "date-time", "2012-10-17T12:00:00Z"],
   ["dtend",
    { "tzid": "Europe/Berlin" },
    "date-time",
    "2011-10-17T13:00:00"
   ]

<span class="h4"><a class="selflink" id="section-3.6.6" href="#section-3.6.6">3.6.6</a>.  Duration (<a href="./rfc5545#section-3.3.6">RFC 5545, Section&nbsp;3.3.6</a>)</span>

   Description:  iCalendar "DURATION" property values are represented by
      a property with the type identifier "duration".  The value
      elements are JSON strings with the same duration value specified
      by [<a href="./rfc5545" title="&quot;Internet Calendaring and Scheduling Core Object Specification (iCalendar)&quot;">RFC5545</a>].

   Example:

   ["duration", {}, "duration", "P1D"]






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<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


<span class="h4"><a class="selflink" id="section-3.6.7" href="#section-3.6.7">3.6.7</a>.  Float (<a href="./rfc5545#section-3.3.7">RFC 5545, Section&nbsp;3.3.7</a>)</span>

   Description:  iCalendar "FLOAT" property values are represented by a
      property with the type identifier "float".  The value elements are
      JSON primitive number values.

   Example:

   ["x-grade", {}, "float", 1.3]

<span class="h4"><a class="selflink" id="section-3.6.8" href="#section-3.6.8">3.6.8</a>.  Integer (<a href="./rfc5545#section-3.3.8">RFC 5545, Section&nbsp;3.3.8</a>)</span>

   Description:  vCard "INTEGER" property values are represented by a
      property with the type identifier "integer".  The value elements
      are JSON primitive number values that MUST resolve to an integer
      value in the range specified in <a href="./rfc5545#section-3.3.8">[RFC5545], Section&nbsp;3.3.8</a>.  Thus, a
      fractional and/or exponential part are only allowed under limited
      circumstances.

   Examples:

   ["percent-complete", {}, "integer", 42]

<span class="h4"><a class="selflink" id="section-3.6.9" href="#section-3.6.9">3.6.9</a>.  Period of Time (<a href="./rfc5545#section-3.3.9">RFC 5545, Section&nbsp;3.3.9</a>)</span>

   Description:  iCalendar "PERIOD" property values are represented by a
      jCal property with the type identifier "period".  The value
      element is an array of JSON strings, with the first element
      representing the start of the period and the second element
      representing the end of the period.  As in [<a href="./rfc5545" title="&quot;Internet Calendaring and Scheduling Core Object Specification (iCalendar)&quot;">RFC5545</a>], the start of
      the period is always formatted as a date-time value, and the end
      of the period MUST be either a date-time or duration value.  Any
      date, date-time, or duration values contained in the period value
      MUST be formatted in accordance to the rules for date, date-time,
      or duration values specified in this document.

   Example:

   ["freebusy",
    { "fbtype": "FREE" },
    "period",
    ["1997-03-08T16:00:00Z", "P1D"]
   ]








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<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


<span class="h4"><a class="selflink" id="section-3.6.10" href="#section-3.6.10">3.6.10</a>.  Recurrence Rule (<a href="./rfc5545#section-3.3.10">RFC 5545, Section&nbsp;3.3.10</a>)</span>

   Description:  iCalendar "RECUR" property values are represented by a
      property with the type identifier "recur".  The value elements are
      objects describing the structured data as specified by [<a href="./rfc5545" title="&quot;Internet Calendaring and Scheduling Core Object Specification (iCalendar)&quot;">RFC5545</a>].
      Each rule part is described by the combination of key and value.
      The key specifies the name of the rule part and MUST be converted
      to lowercase.  The value of the rule part MUST be mapped by the
      following rules:

      *  The value of the "freq" and "wkst" rule parts MUST be a string
         as specified in [<a href="./rfc5545" title="&quot;Internet Calendaring and Scheduling Core Object Specification (iCalendar)&quot;">RFC5545</a>], with case preserved.

      *  The value of the "until" rule part MUST be a date or date-time
         value formatted in accordance to the rules for date or date-
         time specified in this document.

      *  The "count" and "interval" rule parts MUST be specified as a
         single JSON number value.

      *  The following rule parts can have one or more numeric values:
         "bysecond", "byminute", "byhour", "bymonthday", "byyearday",
         "byweekno", "bymonth", and "bysetpos".  If a rule part contains
         multiple values, an array of numbers MUST be used for that rule
         part.  Single-valued rule parts can be represented by either
         using a single number value, omitting the array completely, or
         using an array with one number element.  A jCal parser MUST be
         able to understand both data types.

      *  Similarly, the "byday" rule part can have one or more string
         values.  If it contains multiple values, an array of strings
         MUST be used.  As before, a single-valued rule part can be
         represented using either a single string value or an array with
         one string element, both of which a jCal parser MUST be able to
         understand.

   Example 1:

   ["rrule",
    {},
    "recur",
    {
      "freq": "YEARLY",
      "count": 5,
      "byday": [ "-1SU", "2MO" ],
      "bymonth": 10
    }
   ]



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   Example 2:

   ["rrule",
    {},
    "recur",
    {
      "freq": "MONTHLY",
      "interval": 2,
      "bymonthday": [ 1, 15, -1 ],
      "until": "2013-10-01"
    }
   ]

<span class="h4"><a class="selflink" id="section-3.6.11" href="#section-3.6.11">3.6.11</a>.  Text (<a href="./rfc5545#section-3.3.11">RFC 5545, Section&nbsp;3.3.11</a>)</span>

   Description:  iCalendar "TEXT" property values are represented by a
      property with the type identifier "text".  The value elements are
      JSON strings.

   Example:

   ["comment", {}, "text", "hello, world"]

<span class="h4"><a class="selflink" id="section-3.6.12" href="#section-3.6.12">3.6.12</a>.  Time (<a href="./rfc5545#section-3.3.12">RFC 5545, Section&nbsp;3.3.12</a>)</span>

   Description:  iCalendar "TIME" property values are represented by a
      property with the type identifier "time".  The value elements are
      JSON strings with the same time value specified by [<a href="./rfc5545" title="&quot;Internet Calendaring and Scheduling Core Object Specification (iCalendar)&quot;">RFC5545</a>], but
      represented using the extended format of the complete
      representation specified in [<a href="#ref-ISO.8601.2004">ISO.8601.2004</a>], Section 4.2.2.2.
      Other variations, for example, representation with reduced
      accuracy, MUST NOT be used.  The same restrictions apply with
      respect to leap seconds, time fractions, and time zone offsets as
      specified in <a href="./rfc5545#section-3.3.12">[RFC5545], Section&nbsp;3.3.12</a>.

   ABNF Schema:

   ; hour, minute, and second rules are
   ; defined in [<a href="#ref-ISO.8601.2004">ISO.8601.2004</a>], Section 2.2.
   ; The zone identifier is described in [<a href="#ref-ISO.8601.2004">ISO.8601.2004</a>], Section 4.3.2.
   time-complete =  hour ":" minute ":" second [zone] ; HH:MM:SS

   Example:

   ["x-time-local", {}, "time", "12:30:00"],
   ["x-time-utc", {}, "time", "12:30:00Z"],
   ["x-time-offset", { "tzid": "Europe/Berlin" }, "time", "12:30:00"]




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<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


<span class="h4"><a class="selflink" id="section-3.6.13" href="#section-3.6.13">3.6.13</a>.  URI (<a href="./rfc5545#section-3.3.13">RFC 5545, Section&nbsp;3.3.13</a>)</span>

   Description:  iCalendar "URI" property values are represented by a
      property with the type identifier "uri".  The value elements are
      JSON strings representing the URI.

   Example:

   ["tzurl", {}, "uri", "http://example.org/tz/Europe-Berlin.ics"]

<span class="h4"><a class="selflink" id="section-3.6.14" href="#section-3.6.14">3.6.14</a>.  UTC Offset (<a href="./rfc5545#section-3.3.14">RFC 5545, Section&nbsp;3.3.14</a>)</span>

   Description:  iCalendar "UTC-OFFSET" property values are represented
      by a property with the type identifier "utc-offset".  The value
      elements are JSON strings with the same UTC offset value specified
      by [<a href="./rfc5545" title="&quot;Internet Calendaring and Scheduling Core Object Specification (iCalendar)&quot;">RFC5545</a>], with the exception that the hour and minute
      components are separated by a ":" character, for consistency with
      the [<a href="#ref-ISO.8601.2004">ISO.8601.2004</a>] time zone offset, extended format.

   Example:

   ["tzoffsetfrom", {}, "utc-offset", "-05:00"],
   ["tzoffsetto", {}, "utc-offset", "+12:45"]

<span class="h3"><a class="selflink" id="section-3.7" href="#section-3.7">3.7</a>.  Extensions</span>

   iCalendar extension properties and property parameters (those with an
   "X-" prefix in their name) are handled in the same way as other
   properties and property parameters: the property is represented by an
   array, and the property parameter is represented by an object.  The
   property or parameter name uses the same name as for the iCalendar
   extension, but in lowercase.  For example, the "X-FOO" property in
   iCalendar turns into the "x-foo" jCal property.  See <a href="#section-5">Section 5</a> for
   how to deal with default values for unrecognized extension properties
   or property parameters.

<span class="h2"><a class="selflink" id="section-4" href="#section-4">4</a>.  Converting from jCal into iCalendar</span>

   Converting jCal to iCalendar reverses the process described in
   <a href="#section-3">Section 3</a>.  This section describes a few additional requirements for
   conversion.

   When converting component, property, and property parameter names,
   the names SHOULD be converted to uppercase.  Although iCalendar names
   are case insensitive, common practice is to keep them all uppercase
   following the actual definitions in [<a href="./rfc5545" title="&quot;Internet Calendaring and Scheduling Core Object Specification (iCalendar)&quot;">RFC5545</a>].





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   During conversion, JSON escaping MUST be unescaped.  Afterwards,
   iCalendar escaping, as defined by [<a href="./rfc5545" title="&quot;Internet Calendaring and Scheduling Core Object Specification (iCalendar)&quot;">RFC5545</a>] and [<a href="./rfc6868" title="&quot;Parameter Value Encoding in iCalendar and vCard&quot;">RFC6868</a>], MUST be
   applied.  Finally, long lines SHOULD be folded as described in
   <a href="./rfc5545#section-3.1">[RFC5545], Section&nbsp;3.1</a>.

   Non-binary value types MUST NOT be base64 encoded.

   When converting to iCalendar, the VALUE parameter MUST be added to
   properties whose default value type is unknown, but do not have a
   jCal type identifier "unknown".  The VALUE parameter MAY be omitted
   for properties using the default value type.  The VALUE parameter
   MUST be omitted for properties that have the jCal type identifier
   "unknown".

<span class="h2"><a class="selflink" id="section-5" href="#section-5">5</a>.  Handling Unrecognized Properties or Parameters</span>

   In iCalendar, properties can have one or more value types as
   specified by their definition, with one of those values being defined
   as the default.  When a property uses its default value type, the
   "VALUE" property parameter does not need to be specified on the
   property.  For example, the default value type for "DTSTART" is
   "DATE-TIME", so "VALUE=DATE-TIME" need not be set as a property
   parameter.  However, "DTSTART" also allows a "DATE" value to be
   specified, and if that is used, "VALUE=DATE" has to be set as a
   property parameter.

   When new properties are defined or "X-" properties used, an iCalendar
   to jCal converter might not recognize them, and not know what the
   appropriate default value types are, yet they need to be able to
   preserve the values.  A similar issue arises for unrecognized
   property parameters.

   In jCal, a new "unknown" property value type is introduced.  Its
   purpose is to allow preserving unknown property values when round-
   tripping between jCal and iCalendar.  To avoid collisions, this
   specification reserves the UNKNOWN property value type in iCalendar.
   It MUST NOT be used in any iCalendar as specified by [<a href="./rfc5545" title="&quot;Internet Calendaring and Scheduling Core Object Specification (iCalendar)&quot;">RFC5545</a>], nor
   any extensions to it.  Thus, the type is registered to the iCalendar
   Value Data Types registry in <a href="#section-7.1">Section 7.1</a>.

<span class="h3"><a class="selflink" id="section-5.1" href="#section-5.1">5.1</a>.  Converting iCalendar into jCal</span>

   Any property that does not include a "VALUE" property parameter and
   whose default value type is not known, MUST be converted to a
   primitive JSON string.  The content of that string is the unprocessed
   value text.  Also, value type MUST be set to "unknown".





<span class="grey">Kewisch, et al.              Standards Track                   [Page 18]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-19" ></span>
<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


   To correctly implement this format, it is critical that the type
   "unknown" be used if the default type is not known.  If this
   requirement is ignored and, for example, "text" is used, additional
   escaping may occur, which breaks round-tripping values.

   Any unrecognized property parameter MUST be converted to a string
   value, with its content set to the property parameter value text, and
   treated as if it were a "TEXT" value.

<span class="h3"><a class="selflink" id="section-5.2" href="#section-5.2">5.2</a>.  Converting jCal into iCalendar</span>

   In jCal, the value type is always explicitly specified.  It is
   converted to iCalendar using the iCalendar VALUE parameter, except in
   the following two cases:

   o  If the value type specified in jCal matches the default value type
      in iCalendar, the VALUE parameter MAY be omitted.

   o  If the value type specified in jCal is set to "unknown", the VALUE
      parameter MUST NOT be specified.  The value MUST be taken over in
      iCalendar without processing.

<span class="h3"><a class="selflink" id="section-5.3" href="#section-5.3">5.3</a>.  Examples</span>

   The following is an example of an unrecognized iCalendar property
   (that uses a "DATE-TIME" value as its default), and the equivalent
   jCal representation of that property.

   iCalendar:

   X-COMPLAINT-DEADLINE:20110512T120000Z

   jCal:

   ["x-complaint-deadline", {}, "unknown", "20110512T120000Z"]

   The following is an example of how to cope with jCal data where the
   parser was unable to identify the type.  Note how the "unknown" value
   type is not added to the iCalendar data and escaping, aside from
   standard JSON string escaping, is not processed.

   jCal:

   ["x-coffee-data", {}, "unknown", "Stenophylla;Guinea\\,Africa"]

   iCalendar:

   X-COFFEE-DATA:Stenophylla;Guinea\,Africa



<span class="grey">Kewisch, et al.              Standards Track                   [Page 19]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-20" ></span>
<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


   The following is an example of a jCal property (where the
   corresponding iCalendar property uses an "INTEGER" value as its
   default) and the equivalent iCalendar representation of that
   property.

   jCal:

   ["percent-complete", {}, "integer", 95]

   iCalendar:

   PERCENT-COMPLETE:95

   The following is an example of an unrecognized iCalendar property
   parameter (that uses a "FLOAT" value as its default) specified on a
   recognized iCalendar property and the equivalent jCal representation
   of that property and property parameter.

   iCalendar:

   DTSTART;X-SLACK=30.3;VALUE=DATE:20110512

   jCal:

   ["dtstart", { "x-slack": "30.3" }, "date", "2011-05-12"]

<span class="h2"><a class="selflink" id="section-6" href="#section-6">6</a>.  Security Considerations</span>

   This specification defines how iCalendar data can be "translated"
   between two different data formats -- the original text format and
   JSON -- with a one-to-one mapping to ensure all the semantic data in
   one format (properties, parameters, and values) are preserved in the
   other.  It does not change the semantic meaning of the underlying
   data itself, or impose or remove any security considerations that
   apply to the underlying data.

   The use of JSON as a format does have its own inherent security risks
   as discussed in <a href="./rfc7159#section-12">Section&nbsp;12 of [RFC7159]</a>.  Even though JSON is
   considered a safe subset of JavaScript, it should be kept in mind
   that a flaw in the parser processing JSON could still impose a
   threat, which doesn't arise with conventional iCalendar data.

   With this in mind, a parser for JSON data should be used for jCal
   that is aware of the security implications.  For example, the use of
   JavaScript's eval() function is considered an unacceptable security
   risk, as described in <a href="./rfc7159#section-12">Section&nbsp;12 of [RFC7159]</a>.  A native parser with
   full awareness of the JSON format should be preferred.




<span class="grey">Kewisch, et al.              Standards Track                   [Page 20]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-21" ></span>
<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


   In addition, it is expected that this new format will result in
   iCalendar data being more widely disseminated (e.g., with use in web
   applications rather than just dedicated calendaring applications).

   In all cases, application developers have to conform to the semantics
   of the iCalendar data as defined by [<a href="./rfc5545" title="&quot;Internet Calendaring and Scheduling Core Object Specification (iCalendar)&quot;">RFC5545</a>] and associated
   extensions, and all of the security considerations described in
   <a href="./rfc5545#section-7">Section&nbsp;7 of [RFC5545]</a>, or any associated extensions, are applicable.

<span class="h2"><a class="selflink" id="section-7" href="#section-7">7</a>.  IANA Considerations</span>

   This document defines a MIME media type for use with iCalendar in
   JSON data.  This media type SHOULD be used for the transfer of
   calendaring data in JSON.

   Type name:  application

   Subtype name:  calendar+json

   Required parameters:  none

   Optional parameters:  "method", "component", and "optinfo" as defined
      for the text/calendar media type in <a href="./rfc5545#section-8.1">[RFC5545], Section&nbsp;8.1</a>.

   Encoding considerations:  Same as encoding considerations of
      application/json as specified in <a href="./rfc7159#section-11">[RFC7159], Section&nbsp;11</a>.

   Security considerations:  See <a href="#section-6">Section 6</a>.

   Interoperability considerations:  This media type provides an
      alternative format for iCalendar data based on JSON.

   Published specification:  This specification.

   Applications that use this media type:  Applications that currently
      make use of the text/calendar media type can use this as an
      alternative.  Similarly, applications that use the application/
      json media type to transfer calendaring data can use this to
      further specify the content.

   Fragment identifier considerations:  N/A

   Additional information:

      Deprecated alias names for this type:  N/A

      Magic number(s):  N/A




<span class="grey">Kewisch, et al.              Standards Track                   [Page 21]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-22" ></span>
<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


      File extension(s):  N/A

      Macintosh file type code(s):  N/A

   Person &amp; email address to contact for further information:
      calsify@ietf.org

   Intended usage:  COMMON

   Restrictions on usage:  There are no restrictions on where this media
      type can be used.

   Author:  See the "Authors' Addresses" section of this document.

   Change controller:  IETF

<span class="h3"><a class="selflink" id="section-7.1" href="#section-7.1">7.1</a>.  UNKNOWN iCalendar Value Data Type</span>

   IANA has added the following entry to the iCalendar Data Types
   registry:

   Value name:  UNKNOWN

   Purpose:  To allow preserving property values whose default value
      type is not known during round-tripping between jCal and
      iCalendar.

   Format definition:  N/A

   Description:  The UNKNOWN value data type is reserved for the
      exclusive use of the jCal format.  Its use is described in
      <a href="#section-5">Section 5</a> of this document.

   Example:  As this registration serves as a reservation of the UNKNOWN
      type so that it is not used in iCalendar, there is no applicable
      iCalendar example.  Examples of its usage in jCal can be found in
      this document.

   IANA has made the "Status" column for this entry in the registry say,
   "Reserved - Do not use" and has made the "Reference" column refer to
   <a href="#section-5">Section 5</a> of this document.










<span class="grey">Kewisch, et al.              Standards Track                   [Page 22]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-23" ></span>
<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


<span class="h2"><a class="selflink" id="section-8" href="#section-8">8</a>.  Acknowledgments</span>

   The authors would like to thank the following for their valuable
   contributions: William Gill, Erwin Rehme, Dave Thewlis, Simon
   Perreault, Michael Angstadt, Peter Saint-Andre, Bert Greevenbosch,
   and Javier Godoy.  This specification originated from the work of the
   XML-JSON technical committee of the Calendaring and Scheduling
   Consortium.

<span class="h2"><a class="selflink" id="section-9" href="#section-9">9</a>.  References</span>

<span class="h3"><a class="selflink" id="section-9.1" href="#section-9.1">9.1</a>.  Normative References</span>

   [<a id="ref-ISO.8601.2004">ISO.8601.2004</a>]
              International Organization for Standardization, "Data
              elements and interchange formats -- Information
              interchange -- Representation of dates and times", ISO
              8601, December 2004,
              &lt;<a href="http://www.iso.org/iso/catalogue_detail?csnumber=40874">http://www.iso.org/iso/catalogue_detail?csnumber=40874</a>&gt;.

   [<a id="ref-RFC2119">RFC2119</a>]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", <a href="https://www.rfc-editor.org/bcp/bcp14">BCP 14</a>, <a href="./rfc2119">RFC 2119</a>, March 1997.

   [<a id="ref-RFC3986">RFC3986</a>]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
              Resource Identifier (URI): Generic Syntax", STD 66, <a href="./rfc3986">RFC</a>
              <a href="./rfc3986">3986</a>, January 2005.

   [<a id="ref-RFC4648">RFC4648</a>]  Josefsson, S., "The Base16, Base32, and Base64 Data
              Encodings", <a href="./rfc4648">RFC 4648</a>, October 2006.

   [<a id="ref-RFC5234">RFC5234</a>]  Crocker, D. and P. Overell, "Augmented BNF for Syntax
              Specifications: ABNF", STD 68, <a href="./rfc5234">RFC 5234</a>, January 2008.

   [<a id="ref-RFC5545">RFC5545</a>]  Desruisseaux, B., "Internet Calendaring and Scheduling
              Core Object Specification (iCalendar)", <a href="./rfc5545">RFC 5545</a>,
              September 2009.

   [<a id="ref-RFC6321">RFC6321</a>]  Daboo, C., Douglass, M., and S. Lees, "xCal: The XML
              Format for iCalendar", <a href="./rfc6321">RFC 6321</a>, August 2011.

   [<a id="ref-RFC6868">RFC6868</a>]  Daboo, C., "Parameter Value Encoding in iCalendar and
              vCard", <a href="./rfc6868">RFC 6868</a>, February 2013.

   [<a id="ref-RFC7159">RFC7159</a>]  Bray, T., "The JavaScript Object Notation (JSON) Data
              Interchange Format", <a href="./rfc7159">RFC 7159</a>, March 2014.






<span class="grey">Kewisch, et al.              Standards Track                   [Page 23]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-24" ></span>
<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


<span class="h3"><a class="selflink" id="section-9.2" href="#section-9.2">9.2</a>.  Informative References</span>

   [<a id="ref-calconnect-artifacts">calconnect-artifacts</a>]
              The Calendaring and Scheduling Consortium, "Code Artifacts
              and Schemas", &lt;<a href="http://www.calconnect.org/artifacts.shtml">http://www.calconnect.org/artifacts.shtml</a>&gt;.














































<span class="grey">Kewisch, et al.              Standards Track                   [Page 24]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-25" ></span>
<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


<span class="h2"><a class="selflink" id="appendix-A" href="#appendix-A">Appendix A</a>.  ABNF Schema</span>

   Below is an ABNF schema as per [<a href="./rfc5234" title="&quot;Augmented BNF for Syntax Specifications: ABNF&quot;">RFC5234</a>] for iCalendar in JSON.  ABNF
   symbols not described here are taken from [<a href="./rfc7159" title="&quot;The JavaScript Object Notation (JSON) Data Interchange Format&quot;">RFC7159</a>].  The schema is
   non-normative and given for reference only.

   Additional semantic restrictions apply, especially regarding the
   allowed properties and sub-components per component.  Details on
   these restrictions can be found in this document and [<a href="./rfc5545" title="&quot;Internet Calendaring and Scheduling Core Object Specification (iCalendar)&quot;">RFC5545</a>].

   Additional schemas may be available on the Internet at
   [<a href="#ref-calconnect-artifacts">calconnect-artifacts</a>].

   ; A jCal object is a component with the component-name "vcalendar".
   ; Restrictions to which properties and sub-components may be
   ; specified are to be taken from [<a href="./rfc5545" title="&quot;Internet Calendaring and Scheduling Core Object Specification (iCalendar)&quot;">RFC5545</a>].
   jcalobject = component

   ; A jCal component consists of the name string, properties array, and
   ; component array
   component = begin-array
               DQUOTE component-name DQUOTE value-separator
               properties-array value-separator
               components-array
               end-array

   components-array = begin-array
                      [ component *(value-separator component) ]
                      end-array

   ; A jCal property consists of the name string, parameters object,
   ; type string, and one or more values as specified in this document.
   property = begin-array
              DQUOTE property-name DQUOTE value-separator
              params-object value-separator
              DQUOTE type-name DQUOTE
              property-value *(value-separator property-value)
              end-array
   properties-array = begin-array
                      [ property *(value-separator property) ]
                      end-array

   ; Property values depend on the type-name. Aside from the value types
   ; mentioned here, extensions may make use of other JSON value types.
   ; The non-terminal symbol structured-prop-value covers the special
   ; cases for GEO and REQUEST-STATUS.
   property-value = simple-prop-value / structured-prop-value
   simple-prop-value = string / number / true / false



<span class="grey">Kewisch, et al.              Standards Track                   [Page 25]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-26" ></span>
<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


   structured-prop-value =
       begin-array
       [ structured-element *(value-separator structured-element) ]
       end-array
   structured-element = simple-prop-value

   ; The jCal params-object is a JSON object that follows the semantic
   ; guidelines described in this document.
   params-object = begin-object
                   [ params-member *(value-separator params-member) ]
                   end-object
   params-member = DQUOTE param-name DQUOTE name-separator param-value
   param-value = string / param-multi
   param-multi = begin-array
                 [ string *(value-separator string) ]
                 end-array

   ; The type MUST be a valid type as described by this document. New
   ; value types can be added by extensions.
   type-name = "binary" / "boolean" / "cal-address" / "date" /
               "date-time" / "duration" / "float" / "integer" /
               "period" / "recur" / "text" / "time" / "uri" /
               "utc-offset" / x-type


   ; Component, property, parameter, and type names MUST be lowercase.
   ; Additional semantic restrictions apply as described by this
   ; document and [<a href="./rfc5545" title="&quot;Internet Calendaring and Scheduling Core Object Specification (iCalendar)&quot;">RFC5545</a>].
   component-name = lowercase-name
   property-name = lowercase-name
   param-name = lowercase-name
   x-type = lowercase-name
   lowercase-name = 1*(%x61-7A / DIGIT / "-")

   ; The following rules are defined in [<a href="./rfc7159" title="&quot;The JavaScript Object Notation (JSON) Data Interchange Format&quot;">RFC7159</a>], as mentioned above:
   ;   begin-array / end-array
   ;   begin-object / end-object
   ;   name-separator / value-separator
   ;   string / number / true / false












<span class="grey">Kewisch, et al.              Standards Track                   [Page 26]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-27" ></span>
<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


<span class="h2"><a class="selflink" id="appendix-B" href="#appendix-B">Appendix B</a>.  Examples</span>

   This section contains two examples of iCalendar objects with their
   jCal representation.

<span class="h3"><a class="selflink" id="appendix-B.1" href="#appendix-B.1">B.1</a>.  Example 1</span>

<span class="h4"><a class="selflink" id="appendix-B.1.1" href="#appendix-B.1.1">B.1.1</a>.  iCalendar Data</span>

   BEGIN:VCALENDAR
   CALSCALE:GREGORIAN
   PRODID:-//Example Inc.//Example Calendar//EN
   VERSION:2.0
   BEGIN:VEVENT
   DTSTAMP:20080205T191224Z
   DTSTART:20081006
   SUMMARY:Planning meeting
   UID:4088E990AD89CB3DBB484909
   END:VEVENT
   END:VCALENDAR

<span class="h4"><a class="selflink" id="appendix-B.1.2" href="#appendix-B.1.2">B.1.2</a>.  jCal Data</span>

   ["vcalendar",
     [
       ["calscale", {}, "text", "GREGORIAN"],
       ["prodid", {}, "text", "-//Example Inc.//Example Calendar//EN"],
       ["version", {}, "text", "2.0"]
     ],
     [
       ["vevent",
         [
           ["dtstamp", {}, "date-time", "2008-02-05T19:12:24Z"],
           ["dtstart", {}, "date", "2008-10-06"],
           ["summary", {}, "text", "Planning meeting"],
           ["uid", {}, "text", "4088E990AD89CB3DBB484909"]
         ],
         []
       ]
     ]
   ]










<span class="grey">Kewisch, et al.              Standards Track                   [Page 27]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-28" ></span>
<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


<span class="h3"><a class="selflink" id="appendix-B.2" href="#appendix-B.2">B.2</a>.  Example 2</span>

<span class="h4"><a class="selflink" id="appendix-B.2.1" href="#appendix-B.2.1">B.2.1</a>.  iCalendar Data</span>

   BEGIN:VCALENDAR
   VERSION:2.0
   PRODID:-//Example Corp.//Example Client//EN
   BEGIN:VTIMEZONE
   LAST-MODIFIED:20040110T032845Z
   TZID:US/Eastern
   BEGIN:DAYLIGHT
   DTSTART:20000404T020000
   RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4
   TZNAME:EDT
   TZOFFSETFROM:-0500
   TZOFFSETTO:-0400
   END:DAYLIGHT
   BEGIN:STANDARD
   DTSTART:20001026T020000
   RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
   TZNAME:EST
   TZOFFSETFROM:-0400
   TZOFFSETTO:-0500
   END:STANDARD
   END:VTIMEZONE
   BEGIN:VEVENT
   DTSTAMP:20060206T001121Z
   DTSTART;TZID=US/Eastern:20060102T120000
   DURATION:PT1H
   RRULE:FREQ=DAILY;COUNT=5
   RDATE;TZID=US/Eastern;VALUE=PERIOD:20060102T150000/PT2H
   SUMMARY:Event #2
   DESCRIPTION:We are having a meeting all this week at 12 pm fo
    r one hour\, with an additional meeting on the first day 2 h
    ours long.\nPlease bring your own lunch for the 12 pm meetin
    gs.
   UID:00959BC664CA650E933C892C@example.com
   END:VEVENT
   BEGIN:VEVENT
   DTSTAMP:20060206T001121Z
   DTSTART;TZID=US/Eastern:20060104T140000
   DURATION:PT1H
   RECURRENCE-ID;TZID=US/Eastern:20060104T120000
   SUMMARY:Event #2 bis
   UID:00959BC664CA650E933C892C@example.com
   END:VEVENT
   END:VCALENDAR




<span class="grey">Kewisch, et al.              Standards Track                   [Page 28]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-29" ></span>
<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


<span class="h4"><a class="selflink" id="appendix-B.2.2" href="#appendix-B.2.2">B.2.2</a>.  jCal Data</span>

   ["vcalendar",
     [
       ["prodid", {}, "text", "-//Example Corp.//Example Client//EN"],
       ["version", {}, "text", "2.0"]
     ],
     [
       ["vtimezone",
         [
           ["last-modified", {}, "date-time", "2004-01-10T03:28:45Z"],
           ["tzid", {}, "text", "US/Eastern"]
         ],
         [
           ["daylight",
             [
               ["dtstart", {}, "date-time", "2000-04-04T02:00:00"],
               ["rrule",
                 {},
                 "recur",
                 {
                   "freq": "YEARLY",
                   "byday": "1SU",
                   "bymonth": 4
                 }
               ],
               ["tzname", {}, "text", "EDT"],
               ["tzoffsetfrom", {}, "utc-offset", "-05:00"],
               ["tzoffsetto", {}, "utc-offset", "-04:00"]
             ],
             []
           ],
           ["standard",
             [
               ["dtstart", {}, "date-time", "2000-10-26T02:00:00"],
               ["rrule",
                 {},
                 "recur",
                 {
                   "freq": "YEARLY",
                   "byday": "1SU",
                   "bymonth": 10
                 }
               ],
               ["tzname", {}, "text", "EST"],
               ["tzoffsetfrom", {}, "utc-offset", "-04:00"],
               ["tzoffsetto", {}, "utc-offset", "-05:00"]
             ],



<span class="grey">Kewisch, et al.              Standards Track                   [Page 29]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-30" ></span>
<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


             []
           ]
         ]
       ],
       ["vevent",
         [
           ["dtstamp", {}, "date-time", "2006-02-06T00:11:21Z"],
           ["dtstart",
             { "tzid": "US/Eastern" },
             "date-time",
             "2006-01-02T12:00:00"
           ],
           ["duration", {}, "duration", "PT1H"],
           ["rrule", {}, "recur", { "freq": "DAILY", "count": 5 } ],
           ["rdate",
             { "tzid": "US/Eastern" },
             "period",
             "2006-01-02T15:00:00/PT2H"
           ],
           ["summary", {}, "text", "Event #2"],
           ["description",
            {},
            "text",
            // Note that comments and string concatenation are not
            // allowed per the JSON specification and is used here only
            // to avoid long lines.
            "We are having a meeting all this week at 12 pm for one " +
            "hour, with an additional meeting on the first day 2 " +
            "hours long.\nPlease bring your own lunch for the 12 pm " +
            "meetings."
           ],
           ["uid", {}, "text", "00959BC664CA650E933C892C@example.com"]
         ],
         []
       ],
       ["vevent",
         [
           ["dtstamp", {}, "date-time", "2006-02-06T00:11:21Z"],
           ["dtstart",
             { "tzid": "US/Eastern" },
             "date-time",
             "2006-01-02T14:00:00"
           ],
           ["duration", {}, "duration", "PT1H"],
           ["recurrence-id",
             { "tzid": "US/Eastern" },
             "date-time",
             "2006-01-04T12:00:00"



<span class="grey">Kewisch, et al.              Standards Track                   [Page 30]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-31" ></span>
<span class="grey"><a href="./rfc7265">RFC 7265</a>                          jCal                          May 2014</span>


           ],
           ["summary", {}, "text", "Event #2"],
           ["uid", {}, "text", "00959BC664CA650E933C892C@example.com"]
         ],
         []
       ]
     ]
   ]

Authors' Addresses

   Philipp Kewisch
   Mozilla Corporation
   650 Castro Street, Suite 300
   Mountain View, CA  94041
   USA

   EMail: mozilla@kewis.ch
   URI:   <a href="http://www.mozilla.org/">http://www.mozilla.org/</a>


   Cyrus Daboo
   Apple Inc.
   1 Infinite Loop
   Cupertino, CA  95014
   USA

   EMail: cyrus@daboo.name
   URI:   <a href="http://www.apple.com/">http://www.apple.com/</a>


   Mike Douglass
   Rensselaer Polytechnic Institute
   110 8th Street
   Troy, NY  12180
   USA

   EMail: douglm@rpi.edu
   URI:   <a href="http://www.rpi.edu/">http://www.rpi.edu/</a>












Kewisch, et al.              Standards Track                   [Page 31]
</pre>