JSON data formats for vCard and iCalendar P. Kewisch Internet-Draft Mozilla Intended status: Standards Track October 15, 2013 Expires: April 18, 2014 jCard: The JSON format for vCard draft-ietf-jcardcal-jcard-07 Abstract This specification defines "jCard", a JSON format for vCard data. The vCard data format is a text format for representing and exchanging information about individuals and other entities, for example telephone numbers, email addresses, structured names and delivery addresses. JSON is a lightweight, text-based, language- independent data interchange format commonly used in internet applications. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on April 18, 2014. Copyright Notice Copyright (c) 2013 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of Kewisch Expires April 18, 2014 [Page 1] Internet-Draft jCard October 2013 the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Conventions Used in This Document . . . . . . . . . . . . . . 4 3. Converting from vCard to jCard . . . . . . . . . . . . . . . 4 3.1. Pre-processing . . . . . . . . . . . . . . . . . . . . . 4 3.2. jCard Object and Syntactic Entities (RFC6350 section 6.1.1 and 6.1.2) . . . . . . . . . . . . . . . . . . . . 5 3.3. Properties (RFC6350 section 6) . . . . . . . . . . . . . 5 3.3.1. Special Cases for Properties . . . . . . . . . . . . 7 3.3.1.1. The VERSION Property . . . . . . . . . . . . . . 7 3.3.1.2. Grouping of Properties . . . . . . . . . . . . . 7 3.3.1.3. Structured Property Values . . . . . . . . . . . 8 3.4. Parameters (RFC6350 Section 5) . . . . . . . . . . . . . 10 3.4.1. VALUE parameter . . . . . . . . . . . . . . . . . . . 10 3.4.2. Multi-value Parameters . . . . . . . . . . . . . . . 11 3.5. Values (RFC6350 Section 4) . . . . . . . . . . . . . . . 11 3.5.1. Text (RFC6350 Section 4.1) . . . . . . . . . . . . . 12 3.5.2. URI (RFC6350 Section 4.2) . . . . . . . . . . . . . . 12 3.5.3. Date (RFC6350 Section 4.3.1) . . . . . . . . . . . . 12 3.5.4. Time (RFC6350 Section 4.3.2) . . . . . . . . . . . . 13 3.5.5. Date-Time (RFC6350 Section 4.3.3) . . . . . . . . . . 15 3.5.6. Date and/or Time (RFC6350 Section 4.3.4) . . . . . . 16 3.5.7. Timestamp (RFC6350 Section 4.3.5) . . . . . . . . . . 16 3.5.8. Boolean (RFC6350 Section 4.4) . . . . . . . . . . . . 17 3.5.9. Integer (RFC6350 Section 4.5) . . . . . . . . . . . . 17 3.5.10. Float (RFC6350 Section 4.6) . . . . . . . . . . . . . 18 3.5.11. UTC Offset (RFC6350 Section 4.7) . . . . . . . . . . 18 3.5.12. Language Tag (RFC6350 Section 4.8) . . . . . . . . . 18 3.6. Extensions (RFC6350 Section 6.10) . . . . . . . . . . . . 19 4. Converting from jCard into vCard . . . . . . . . . . . . . . 19 5. Handling Unrecognized Properties or Parameters . . . . . . . 19 5.1. Converting vCard into jCard . . . . . . . . . . . . . . . 20 5.2. Converting jCard into vCard . . . . . . . . . . . . . . . 20 5.3. Examples . . . . . . . . . . . . . . . . . . . . . . . . 20 6. Implementation Status (to be removed prior to publication as an RFC) . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 7. Security Considerations . . . . . . . . . . . . . . . . . . . 22 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 23 8.1. GROUP vCard Parameter . . . . . . . . . . . . . . . . . . 24 8.2. UNKNOWN vCard Value Data Type . . . . . . . . . . . . . . 25 9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 25 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 25 10.1. Normative References . . . . . . . . . . . . . . . . . . 26 10.2. Informative References . . . . . . . . . . . . . . . . . 26 Kewisch Expires April 18, 2014 [Page 2] Internet-Draft jCard October 2013 Appendix A. ABNF Schema . . . . . . . . . . . . . . . . . . . . 27 Appendix B. Examples . . . . . . . . . . . . . . . . . . . . . . 28 B.1. Example: vCard of the author of RFC6350 . . . . . . . . . 29 B.1.1. vCard Data . . . . . . . . . . . . . . . . . . . . . 29 B.1.2. jCard Data . . . . . . . . . . . . . . . . . . . . . 29 Appendix C. Change History (to be removed prior to publication as an RFC) . . . . . . . . . . . . . . . . . . . . . 30 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 32 1. Introduction The vCard data format [RFC6350] provides for the capture and exchange of information normally stored within an address book or directory application. The vCard format has gone through multiple revisions, most recently vCard 4. As certain similarities exist between vCard and the iCalendar data format [RFC5545], there is also an effort to define a JSON-based data format for calendar information called jCal [I-D.ietf-jcardcal-jcal] that parallels the format defined in this specification. The term JSON describes the JavaScript Object Notation defined in [RFC4627]. The purpose of this specification is to define "jCard", a JSON format for vCard data. One main advantage to using a JSON-based format over the classic vCard format is easier processing for JavaScript based widgets and libraries, especially in the scope of web-based applications. The key design considerations are essentially the same as those for [I-D.ietf-jcardcal-jcal] and [RFC6321], that is: Round-tripping (converting a vCard instance to jCard 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 vCard data semantics are to be preserved, allowing a simple consumer to easily browse the data in jCard. A full understanding of vCard is still required in order to modify and/or fully comprehend the directory data. Extensions to the underlying vCard specification must not lead to requiring an update to jCard. Kewisch Expires April 18, 2014 [Page 3] Internet-Draft jCard October 2013 2. Conventions Used in This Document The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119]. The underlying format used for jCard 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 Section 1 of [RFC4627]. 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. 3. Converting from vCard to jCard This section describes how vCard objects are converted to jCard using a simple mapping between the vCard data model and JSON elements. In [RFC6350], vCard objects are comprised of a set of "properties", "parameters" and "values". The top level of a vCard object contains "properties". A "property" has a "value" and a set of zero or more "parameters". Each of these entities have a representation in jCard, defined in the following sections. The representation of a vCard object in JSON will be named "jCard object" throughout this document. 3.1. Pre-processing vCard uses a line folding mechanism to limit lines of data to a maximum line length (typically 75 octets) to ensure maximum likelihood of preserving data integrity as it is transported via various means (e.g., email) - see Section 3.2 of [RFC6350]. vCard data uses an "escape" character sequence for text values and property parameter values. See Section 3.4 of [RFC6350] as well as [RFC6868]. When converting from vCard to jCard, first vCard lines MUST be unfolded. Afterwards, any vCard escaping MUST be unescaped. Finally JSON escaping (e.g., for control characters) MUST be applied. The reverse order applies when converting from jCard to vCard. First, JSON escaping MUST be unescaped. Afterwards, vCard escaping MUST be applied. Finally, long lines SHOULD be folded as described in [RFC6350]. Kewisch Expires April 18, 2014 [Page 4] Internet-Draft jCard October 2013 One key difference in the formatting of values used in vCard and jCard is that in jCard the specification uses date/time values aligned with the extended format of [ISO.8601.2004], which is more commonly used in internet applications that make use of the JSON format. The sections of this document describing the various date and time formats contain more information on the use of the complete representation, reduced accuracy or truncated representation. 3.2. jCard Object and Syntactic Entities (RFC6350 section 6.1.1 and 6.1.2) In [RFC6350] Section 6.1.1 and 6.1.2, the "BEGIN" and "END" properties delimit a syntactic vCard entity. In jCard, each syntactic entity is represented by an array with two elements and is named "jCard object". The first element is the string "vcard", the second element is an array of jCard properties as described in Section 3.3, belonging to the entity. Although [RFC6350] defines BEGIN and END to be properties, they MUST NOT appear as properties of the jCard. Instead, the jCard object is sufficient to define a vCard entity. When converting from jCard to vCard, the BEGIN and END properties MUST be added to enclose the properties of the jCard object. Example: ["vcard", [ /* Add properties in place of this comment */ ] ] Consumers of this format wishing to define content that can represent multiple jCard objects within the same JSON document can use a simple JSON array, each element being a single jCard object. 3.3. Properties (RFC6350 section 6) Each individual vCard property is represented in jCard by an array with three fixed elements, followed by one or more additional elements, depending on if the property is a multi-value property as described in Section 3.3 of [RFC6350]. The array consists of the following fixed elements: Kewisch Expires April 18, 2014 [Page 5] Internet-Draft jCard October 2013 1. The name of the property, as a lowercase string. The vCard format specifies that property names are case-insensitive, and recommends that they be rendered in uppercase. In jCard, they MUST be in lowercase. 2. An object containing the parameters as described in Section 3.4. If the property has no parameters, an empty object is used to represent that. 3. The type identifier string of the value, in lowercase. It is important that parsers check this to determine the data type of the value, and that they do not rely on assumptions. For example, for structured values the data type will be "array". The remaining elements of the array are used for one or more values of the property. For single-value properties, the array has exactly four elements; for multi-valued properties, 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 all other properties are single-valued: ["vcard", [ ["version", {}, "text", "4.0"], ["fn", {}, "text", "John Doe"], ["gender", {}, "text", "M"], ["categories", {}, "text", "computers", "cameras"], ... ] ] As described in Section 3.3.1.3, a property value may be a structured property value, in which case it is represented as an array encapsulated in the array that represents the overall property. Strictly speaking, this means that the property value is not represented in the format indicated by the type identifier, but by an array instead. However, the values inside the encapsulated array are of the format identified by the type identifier. The above also holds for multi-valued properties, where some of the values may be structured property values, and therefore are represented as an encapsulated array. A special case is where a value in an encapsulated array consists of multiple components itself, in which case it is represented as yet Kewisch Expires April 18, 2014 [Page 6] Internet-Draft jCard October 2013 another nested array, with elements matching the value type. Section 3.3.1.3 describes this in more detail. The above illustrates the importance for the parser to check the format of each property value, as it might either directly match the value type, or it might be a structured value where nested sub- elements match the value type. 3.3.1. Special Cases for Properties This section describes some properties that have special handling when converting to jCard. 3.3.1.1. The VERSION Property The vCard format specification [RFC6350] defines the VERSION property to be mandatory. The "version" property MUST be represented in the corresponding jCard component, with the same value as in the vCard. vCards that conform to RFC 6350 will contain the value "4.0". Also in accordance to [RFC6350], the "version" property MUST be the first element of the array containing the properties of a jCard. 3.3.1.2. Grouping of Properties In vCard [RFC6350] related properties can be grouped together using a grouping construct. The grouping is accomplished by adding a prefix to the property name, which consists of the group name followed by a dot. In jCard the same grouping is achieved through a "group" parameter, that holds the group name. In jCard a property name therefore MUST NOT be prefixed by a group name. The "GROUP" parameter MUST NOT be used in vCard as per [RFC6350] it is merely registered to reserve the parameter, avoiding collisions. Formal registration occurs in Section 8.1. 3.3.1.2.1. Group Conversion Rules In jCard, the parameter's value is a single opaque string. Conversion rules are as follows: o From vCard to jCard, the group construct (see [RFC6350], Section 3.3, Page 7) is removed. In its place, the "group" parameter is used. Its value is a string corresponding to the group name, which is case-insensitive both in vCard and jCard. The name's case SHOULD be converted into lowercase. Kewisch Expires April 18, 2014 [Page 7] Internet-Draft jCard October 2013 o When converting from jCard to vCard, the value of the "group" parameter followed by a dot is prefixed to the property name, and the "group" parameter is discarded. The "GROUP" parameter MUST NOT appear in the resulting vCard. Following recommendations in [RFC6350], the name's case SHOULD be converted into uppercase. Example: CONTACT.FN:Mr. John Q. Public\, Esq. is equivalent to: [ "fn", { "group": "CONTACT" }, "text", "Mr. John Q. Public, Esq." ] 3.3.1.3. Structured Property Values The vCard specification defines properties with structured values, for example GENDER or ADR. In vCard, a structured text value consists of one or multiple text components, delimited by the SEMICOLON character. Its equivalent in jCard is a structured property value, which is an array containing one element for each text component, with empty/missing text components represented by zero-length strings. vCard Example: ADR:;;123 Main Street;Any Town;CA;91921-1234;U.S.A. jCard Example: ["adr", {}, "text", [ "", "", "123 Main Street", "Any Town", "CA", "91921-1234", "U.S.A." ] ] Some vCard properties, for example ADR, also allow a structured value element that itself has multiple values. In this case, the element of the array describing the structured value is itself an array with one element for each of the component's multiple values. vCard Example: Kewisch Expires April 18, 2014 [Page 8] Internet-Draft jCard October 2013 ADR:;;My Street,Left Side,Second Shack;Hometown;PA;18252;U.S.A. jCard Example: ["adr", {}, "text", [ "", "", ["My Street", "Left Side", "Second Shack"], "Hometown", "PA", "18252", "U.S.A." ] ] In both cases, the array element values MUST have the primitive type that matches the jCard type identifier. In [RFC6350], there are only structured text values and thus only JSON strings are used. Extensions may for example define structured number or boolean values, where JSON number or boolean types MUST be used. Although it is allowed for a structured property value to hold just one component, it is RECOMMENDED to represent it as a single text value instead, omitting the array completely. Nevertheless, a simple implementation MAY choose to retain the array, with a single text value as its element. Similarly, structured values that consist of two text components with one being optional (for example, GENDER) can be represented as a single text value. Therefore, parsers of jCard data SHOULD check even known property values for structured information by considering the JSON data type of the value, which can be an array or a primitive value. This is especially important for languages where accessing array members is done by the same construct as accessing characters of a string. Examples: ["gender", {}, "text", ["F", "grrrl"] ], ["gender", {}, "text", "M" ] Per [RFC6350] Section 6.3.1, the component separator MUST be specified even if the component value is missing. Similarly, the jCard array containing the structured data MUST contain all required elements, even if they are empty. vCard Example: Kewisch Expires April 18, 2014 [Page 9] Internet-Draft jCard October 2013 ADR;LABEL="123 Maple Ave\nSuite 901\nVancouver BC\nA1B 2C9\nCan ada":;;;;;; jCard Example: ["adr", {"label":"123 Maple Ave\nSuite 901\nVancouver BC\nA1B 2C9\nCanada"}, "text", ["", "", "", "", "", "", ""] ] 3.4. Parameters (RFC6350 Section 5) Property parameters are represented as a JSON object where each key- value pair represents the vCard 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 "LANGUAGE" property parameter is represented in jCard by the "language" key. Any new vCard parameters added in the future will be converted in the same way. Example: ["role", { "language": "tr" }, "text", "roca"], 3.4.1. VALUE parameter vCard defines a "VALUE" property parameter (Section 5.2 of [RFC6350]). 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 vCard to jCard, 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 jCard into vCard is done as follows: Kewisch Expires April 18, 2014 [Page 10] Internet-Draft jCard October 2013 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. See Section 5 for information on handling unknown value types. 3.4.2. Multi-value Parameters In [RFC6350], some parameters allow using a COMMA-separated list of values. To ease processing in jCard, the value to such parameters MUST be represented in an array containing the separated values. The array elements MUST be string values. Single-value parameters SHOULD be represented using a single string value, although a more simple implementation might prefer an array with one string element. An example for a such parameter is the vCard "SORT-AS" parameter, more such parameters may be added in extensions. The vCard 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 jCard. Example: ["vcard", [ ["version", {}, "text", "4.0"], ["n", { "sort-as": ["Harten", "Rene"] }, "text", ["van der Harten", "Rene", "J.", "Sir", "R.D.O.N."] ], ["fn", {}, "text", "Rene van der Harten"] ... ] ] 3.5. Values (RFC6350 Section 4) Kewisch Expires April 18, 2014 [Page 11] Internet-Draft jCard October 2013 The following subsections specify how vCard property value data types, which are defined in the subsections of [RFC6350] Section 4, are represented in jCard. 3.5.1. Text (RFC6350 Section 4.1) Description: vCard "TEXT" property values are represented by a property with the type identifier "text". The value elements are JSON strings. For details on structured text values, see Section 3.3.1.3. Example: ["kind", {}, "text", "group"] 3.5.2. URI (RFC6350 Section 4.2) Description: vCard "URI" property values are represented by a property with the type identifier "uri". The value elements are JSON strings. Example: ["source", {}, "uri", "ldap://ldap.example.com/cn=babs%20jensen"] 3.5.3. Date (RFC6350 Section 4.3.1) Description: vCard "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 [RFC6350], but represented using the extended format specified in [ISO.8601.2004], Section 4.1.2. If the complete representation is not used, the same date format restrictions regarding reduced accuracy, truncated representation and expanded representation noted in [RFC6350] Section 4.3.1 apply. Whenever the extended format is not applicable, the basic format MUST be used. ABNF Schema: date-complete = year "-" month "-" day ;YYYY-MM-DD date-noreduc = date-complete / "--" month "-" day; --MM-DD / "---" day; ---DDD date = date-noreduc Kewisch Expires April 18, 2014 [Page 12] Internet-Draft jCard October 2013 / year; YYYY / year "-" month ; YYYY-MM / "--" month; --MM Examples: ["bday", {}, "date", "1985-04-12"], ["bday", {}, "date", "1985-04"], ["bday", {}, "date", "1985"], ["bday", {}, "date", "--04-12"], ["bday", {}, "date", "---12"] This table contains possible conversions between the vCard DATE format its jCard date. This information is just an example and not a formal specification of the syntax. The specification can be found in [ISO.8601.2000] and [ISO.8601.2004]: +-----------+----------+------------+ | | vCard | jCard | +-----------+----------+------------+ | Complete | 19850412 | 1985-04-12 | | | | | | Reduced | 1985-04 | 1985-04 | | | | | | Reduced | 1985 | 1985 | | | | | | Truncated | --0412 | --04-12 | | | | | | Truncated | --04 | --04 | | | | | | Truncated | ---12 | ---12 | +-----------+----------+------------+ 3.5.4. Time (RFC6350 Section 4.3.2) Description: vCard "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 [RFC6350], but represented using the extended format specified in [ISO.8601.2004], Section 4.2. If the complete representation is not used, the same time format restrictions regarding reduced accuracy, decimal fraction and truncated representation noted in [RFC6350] Section 4.3.2 apply. Whenever the extended format is not applicable, the basic format MUST be used. The seconds value of 60 MUST only be used to account for positive "leap" seconds and Kewisch Expires April 18, 2014 [Page 13] Internet-Draft jCard October 2013 the midnight hour is always represented by 00, never 24. Fractions of a second are not supported by this format. In jCard, UTC offsets are permitted within a time value; note that this differs from jCal [I-D.ietf-jcardcal-jcal], where they are not permitted. ABNF Schema: time-notrunc = hour [":" minute [":" second]] [zone] time = time-notrunc / "-" minute ":" second [zone]; -mm:ss / "-" minute [zone]; -mm / "--" second [zone]; --ss Examples: ["x-time-local", {}, "time", "12:30:00"], ["x-time-utc", {}, "time", "12:30:00Z"], ["x-time-offset", {}, "time", "12:30:00-08:00"], ["x-time-reduced", {}, "time", "23"], ["x-time-truncated", {}, "time", "-30"] This table contains possible conversions between the vCard TIME format its jCard time. This information is just an example and not a formal specification of the syntax. The specification can be found in [ISO.8601.2000] and [ISO.8601.2004]: +-----------+--------+----------+ | | vCard | jCard | +-----------+--------+----------+ | Complete | 232050 | 23:20:50 | | | | | | Reduced | 2320 | 23:20 | | | | | | Reduced | 23 | 23 | | | | | | Truncated | -2050 | -20:50 | | | | | | Truncated | -20 | -20 | | | | | | Truncated | --50 | --50 | +-----------+--------+----------+ Kewisch Expires April 18, 2014 [Page 14] Internet-Draft jCard October 2013 Also, all combinations may have any zone designator appended, as in the complete representation. 3.5.5. Date-Time (RFC6350 Section 4.3.3) Description: vCard "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 [RFC6350], but represented using the extended format specified in [ISO.8601.2004], Section 4.3. If the complete representation is not used, the same date and time format restrictions as in Section 3.5.4 and Section 3.5.3 apply. Just as in [RFC6350], truncation of the date part is permitted. Example: ["anniversary", {}, "date-time", "2013-02-14T12:30:00"], ["anniversary", {}, "date-time", "2013-01-10T19:00:00Z"], ["anniversary", {}, "date-time", "2013-08-15T09:45:00+01:00"], ["anniversary", {}, "date-time", "---15T09:45:00+01:00"] This table contains possible conversions between the vCard DATE-TIME format its jCard date-time. This information is just an example and not a formal specification of the syntax. The specification can be found in [ISO.8601.2000] and [ISO.8601.2004]: +----------------+----------------------+---------------------------+ | Representation | vCard | jCard | +----------------+----------------------+---------------------------+ | Complete | 19850412T232050 | 1985-04-12T23:20:50 | | | | | | Complete | 19850412T232050Z | 1985-04-12T23:20:50Z | | | | | | Complete | 19850412T232050+0400 | 1985-04-12T23:20:50+04:00 | | | | | | Complete | 19850412T232050+04 | 1985-04-12T23:20:50+04 | | | | | | Reduced | 19850412T2320 | 1985-04-12T23:20 | | | | | | Reduced | 19850412T23 | 1985-04-12T23 | | | | | | Truncated and | --0412T2320 | --04-12T23:20 | | Reduced | | | | | | | | Truncated and | --04T2320 | --04T23:20 | | Reduced | | | | | | | Kewisch Expires April 18, 2014 [Page 15] Internet-Draft jCard October 2013 | Truncated and | ---12T2320 | ---12T23:20 | | Reduced | | | | | | | | Truncated and | --0412T2320 | --04-12T23:20 | | Reduced | | | | | | | | Truncated and | --04T23 | --04T23 | | Reduced | | | +----------------+----------------------+---------------------------+ As specified in [ISO.8601.2000], the lower order components may not be omitted in the date part (reduced accuracy) and the higher order components may not be omitted in the time part (truncation). Also, all combinations may have any zone designator appended, as in the complete representation. 3.5.6. Date and/or Time (RFC6350 Section 4.3.4) Description: vCard "DATE-AND-OR-TIME" property values are represented by a property with the type identifier "date-and-or- time". The value elements are either a date-time (Section 3.5.5), a date (Section 3.5.3) or a time (Section 3.5.4) value. Just as in [RFC6350] Section 4.3.4, a stand-alone time value MUST always be preceded by a "T". Example: ["bday", {}, "date-and-or-time", "2013-02-14T12:30:00"], ["bday", {}, "date-and-or-time", "---22T14:00"] ["bday", {}, "date-and-or-time", "1985"], ["bday", {}, "date-and-or-time", "T12:30"] 3.5.7. Timestamp (RFC6350 Section 4.3.5) Description: vCard "TIMESTAMP" property values are represented by a property with the type identifier "timestamp". The value elements are JSON strings with the same timestamp value specified by [RFC6350], but represented using the extended format and complete representation specified in [ISO.8601.2004], Section 4.3.2. Example: Kewisch Expires April 18, 2014 [Page 16] Internet-Draft jCard October 2013 ["rev", {}, "timestamp", "2013-02-14T12:30:00"], ["rev", {}, "timestamp", "2013-02-14T12:30:00Z"], ["rev", {}, "timestamp", "2013-02-14T12:30:00-05"], ["rev", {}, "timestamp", "2013-02-14T12:30:00-05:00"] This table contains possible conversions between the vCard TIMESTAMP format its jCard timestamp. This information is just an example and not a formal specification of the syntax. The specification can be found in [ISO.8601.2000] and [ISO.8601.2004]: +----------------+----------------------+---------------------------+ | Representation | vCard | jCard | +----------------+----------------------+---------------------------+ | Complete | 19850412T232050 | 1985-04-12T23:20:50 | | | | | | Complete | 19850412T232050Z | 1985-04-12T23:20:50Z | | | | | | Complete | 19850412T232050+0400 | 1985-04-12T23:20:50+04:00 | | | | | | Complete | 19850412T232050+04 | 1985-04-12T23:20:50+04 | +----------------+----------------------+---------------------------+ 3.5.8. Boolean (RFC6350 Section 4.4) Description: vCard "BOOLEAN" property values are represented by a property with the type identifier "boolean". The value element is a JSON boolean value. Example: ["x-non-smoking", {}, "boolean", true] 3.5.9. Integer (RFC6350 Section 4.5) Description: vCard "INTEGER" property values are represented by a property with the type identifier "integer". The value elements are JSON primitive number values. Examples: ["x-karma-points", {}, "integer", 42] JSON allows decimals (e.g. 3.14) and exponents (e.g. 2e10) to be used in numeric values. jCard does not prohibit this for "integer" Kewisch Expires April 18, 2014 [Page 17] Internet-Draft jCard October 2013 property values. However, since vCard does not support decimals or exponents in integers, any decimals and exponents MUST be eliminated when converting an "integer" value type property from jCard to vCard. 3.5.10. Float (RFC6350 Section 4.6) Description: vCard "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] JSON allows exponents (e.g. 2e10) to be used in numeric values. jCard does not prohibit this for "float" property values. However, since vCard does not support exponents in floats, any exponents MUST be eliminated when converting a "float" value type property from jCard to vCard. 3.5.11. UTC Offset (RFC6350 Section 4.7) Description: vCard "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 [RFC6350], with the exception that the hour and minute components are separated by a ":" character, for consistency with the [ISO.8601.2004] timezone offset, extended format. Example: // Note: [RFC6350] mentions use of utc-offset // for the TZ property as NOT RECOMMENDED ["tz", {}, "utc-offset", "-05:00"] 3.5.12. Language Tag (RFC6350 Section 4.8) Description: vCard "LANGUAGE-TAG" property values are represented by a property with the type identifier "language-tag". The value elements are JSON strings containing a single language-tag, as defined in [RFC5646]. Example: ["lang", {}, "language-tag", "de"] Kewisch Expires April 18, 2014 [Page 18] Internet-Draft jCard October 2013 3.6. Extensions (RFC6350 Section 6.10) vCard 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, the property parameter represented by an object. The property or parameter name uses the same name as for the vCard extension, but in lowercase. For example, the "X-FOO" property in vCard turns into the "x-foo" jCard property. See Section 5 for how to deal with default values for unrecognized extension properties or property parameters. 4. Converting from jCard into vCard When converting property and property parameter values, the names SHOULD be converted to uppercase. Although vCard names are case insensitive, common practice is to keep them all uppercase following the actual definitions in [RFC6350]. Character escaping and line folding MUST be applied to the resulting vCard data as required by [RFC6350] and [RFC6868]. When converting to vCard, the VALUE parameter MUST be added to properties whose default value type is unknown, but do not have a jCard type identifier "unknown". The VALUE parameter MAY be omitted for properties using the default value type. The VALUE parameter MUST be omitted for properties which have the jCard type identifier "unknown". 5. Handling Unrecognized Properties or Parameters In vCard, 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, "BDAY"'s default value type is "date-and-or-time", so "VALUE=date-and-or-time" need not be set as a property parameter. However, "BDAY" also allows a "text" value to be specified, and if that is used, "VALUE=text" has to be set as a property parameter. When new properties are defined or "X-" properties used, a vCard to jCard 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 jCard, a new "unknown" property value type is introduced. Its purpose is to allow preserving unknown property values when round- Kewisch Expires April 18, 2014 [Page 19] Internet-Draft jCard October 2013 tripping between jCard and vCard. To avoid collisions, this specification reserves the UNKNOWN property value type in vCard. It MUST NOT be used in any vCard as specified by [RFC6350], nor any extensions to it. The type is hence registered to the vCard Value Data Types registroy in Section 8.2. 5.1. Converting vCard into jCard 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". To correctly implement this format, it is critical that if the default type is not known that the value type "unknown" is used. 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, treated as if it were a "TEXT" value. 5.2. Converting jCard into vCard In jCard the value type is always explicitly specified. It is converted to vCard using the vCard VALUE parameter, except in the following two cases: o If the value type specified in jCard matches the default value type in vCard, the VALUE parameter MAY be omitted. o If the value type specified in jCard is set to "unknown", the VALUE parameter MUST NOT be specified. The value MUST be taken over in vCard without processing. 5.3. Examples The following is an example of an unrecognized vCard property (that uses an "URI" value as its default), and the equivalent jCard representation of that property. vCard: X-COMPLAINT-URI:mailto:abuse@example.org jCard: Kewisch Expires April 18, 2014 [Page 20] Internet-Draft jCard October 2013 ["x-complaint-uri", {}, "unknown", "mailto:abuse@example.org"] The following is an example of how to cope with jCard data where the parser was unable to identify the value type. Note how the "unknown" value type is not added to the vCard data and escaping, aside from standard JSON string escaping, is not processed. jCard: ["x-coffee-data", {}, "unknown", "Stenophylla;Guinea\\,Africa"] vCard: X-COFFEE-DATA:Stenophylla;Guinea\,Africa There are no standard properties in [RFC6350] that have a default type of integer. Consequently, this example uses the following extended property which we treat as having a default type known to the parser, namely integer, in order to illustrate how a property with a known default type would be transformed. jCard: ["x-karma-points", {}, "integer", 95] vCard: X-KARMA-POINTS:95 The following is an example of an unrecognized vCard property parameter (that uses a "FLOAT" value as its default) specified on a recognized vCard property, and the equivalent jCard representation of that property and property parameter. vCard: GENDER;X-PROBABILITY=0.8:M jCard: ["gender", { "x-probability": "0.8" }, "text", "M"] Kewisch Expires April 18, 2014 [Page 21] Internet-Draft jCard October 2013 6. Implementation Status (to be removed prior to publication as an RFC) This section describes libraries known to implement this draft as per [I-D.sheffer-running-code]. 1. ICAL.js - Philipp Kewisch, James Lal. A JavaScript parser for iCalendar (rfc5545) Source: https://github.com/mozilla-comm/ical.js/ Maturity: alpha (for jCard) Coverage: Currently geared towards jCal, therefore not all formats are supported. Includes an online validator. (as of rev 847c67c501, 2013-02-14) Licensing: MPL, Mozilla Public License 2.0 2. Py Calendar - Cyrus Daboo. iCalendar/vCard Library Source: https://svn.calendarserver.org/repository/calendarserver /PyCalendar/branches/json/ Maturity: production Coverage: All aspects of this draft, up to version 01. Licensing: Apache License, Version 2.0 3. ez-vcard - Michael Angstadt. A vCard parser library written in Java Source: https://code.google.com/p/ez-vcard/ Maturity: production Coverage All aspects of this draft. Licensing: New BSD License Additionally, interoperability testing of this draft is an ongoing effort under members of calconnect, the Calendaring and Scheduling Consortium. CalDAV Vendors are looking into supporting this draft. 7. Security Considerations This specification defines how vCard data can be "translated" between two different data formats - the original text format and JSON - with Kewisch Expires April 18, 2014 [Page 22] Internet-Draft jCard October 2013 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 Section 7 of [RFC4627]. 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 vCard data. With this in mind, a parser for JSON data should be used for jCard that is aware of the security implications. For example, the use of JavaScript's eval() function is only allowed using the regular expression in Section 6 of [RFC4627]. A native parser with full awareness of the JSON format should be preferred. In addition, it is expected that this new format will result in vCard data being more widely disseminated (e.g., with use in web applications rather than just dedicated "contact managers"). In all cases, application developers have to conform to the semantics of the vCard data as defined by [RFC6350] and associated extensions, and all of the security considerations described in Section 9 of [RFC6350], or any associated extensions, are applicable. 8. IANA Considerations This document defines a MIME media type for use with vCard in JSON data. This media type SHOULD be used for the transfer of calendaring data in JSON. Type name: application Subtype name: vcard+json Required parameters: none Optional parameters: "version", as defined for the text/vcard media media type in [RFC6350], Section 10.1. Encoding considerations: Same as encoding considerations of application/json as specified in [RFC4627], Section 6. Security considerations: See Section 7. Kewisch Expires April 18, 2014 [Page 23] Internet-Draft jCard October 2013 Interoperability considerations: This media type provides an alternative format for vCard data based on JSON. Published specification: This specification. Applications which use this media type: Applications that currently make use of the text/vcard media type can use this as an alternative. Similarly, Applications that use the application/ json media type to transfer directory 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 File extension(s): N/A Macintosh file type code(s): N/A Person & email address to contact for further information: vcarddav@ietf.org Intended usage: COMMON Restrictions on usage: There are no restrictions on where this media type can be used. Author: See the "Author's Address" section of this document. Change controller: IETF 8.1. GROUP vCard Parameter IANA has added the GROUP parameter to the vCard Parameters registry, initialied in Section 10.3.2 of [RFC6350]. Usage of the GROUP parameter is further described in Section 3.3.1.2 of this document. Namespace: Parameter name: GROUP Purpose: To simplify the jCard format. Kewisch Expires April 18, 2014 [Page 24] Internet-Draft jCard October 2013 Description: The GROUP parameter is reserved for the exclusive use of the jCard format described in this document. It MUST NOT be used in plain vCard [RFC6350], nor in xCard [RFC6351]. Format definition: When converting from jCard to vCard, the value of the GROUP parameter is used as part of the property name. Therefore the value is restricted to characters allowed in property names, namely ALPHA, DIGIT and "-" characters. When used, the GROUP parameter MUST NOT be empty. Example: As this registration serves as a reservation of the GROUP parameter so that it is not used in vCard, there is no applicable vCard example. Examples of its usage in jCard can be found in this document. 8.2. UNKNOWN vCard Value Data Type IANA has added the UNKNOWN value data type to the vCard Value Data Types registry, initialized in Section 10.3.3 of [RFC6350]. Usage of the UNKNOWN type is further described in Section 5 of this document. Value name: UNKNOWN Purpose: To allow preserving property values whose default value type is not known during round-tripping between jCard and vCard. Format definition: (Not applicable) Description: The UNKNOWN value data type is reserved for the exclusive use of the jCard format. It MUST NOT be used in plain vCard [RFC6350]. Example: As this registration serves as a reservation of the UNKNOWN type so that it is not used in vCard, there is no applicable vCard example. Examples of its usage in jCard can be found in this document. 9. Acknowledgments The author would like to thank the following for their valuable contributions: Cyrus Daboo, Mike Douglass, William Gill, Erwin Rehme, and Dave Thewlis. Simon Perreault, Michael Angstadt, Peter Saint- Andre, Bert Greevenbosch, Javier Godoy. This specification originated from the work of the XML-JSON technical committee of the Calendaring and Scheduling Consortium. 10. References Kewisch Expires April 18, 2014 [Page 25] Internet-Draft jCard October 2013 10.1. Normative References [ISO.8601.2000] International Organization for Standardization, ""Data elements and interchange formats -- Information interchange -- Representation of dates and times" ", ISO 8601, 12 2000. [ISO.8601.2004] International Organization for Standardization, ""Data elements and interchange formats -- Information interchange -- Representation of dates and times" ", ISO 8601, 12 2004. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC4627] Crockford, D., "The application/json Media Type for JavaScript Object Notation (JSON)", RFC 4627, July 2006. [RFC5234] Crocker, D. and P. Overell, "Augmented BNF for Syntax Specifications: ABNF", STD 68, RFC 5234, January 2008. [RFC5646] Phillips, A. and M. Davis, "Tags for Identifying Languages", BCP 47, RFC 5646, September 2009. [RFC6350] Perreault, S., "vCard Format Specification", RFC 6350, August 2011. [RFC6868] Daboo, C., "Parameter Value Encoding in iCalendar and vCard", RFC 6868, February 2013. 10.2. Informative References [I-D.ietf-jcardcal-jcal] Kewisch, P., Daboo, C., and M. Douglass, "jCal: The JSON format for iCalendar", draft-ietf-jcardcal-jcal-00 (work in progress), March 2013. [I-D.sheffer-running-code] Sheffer, Y. and A. Farrel, "Improving Awareness of Running Code: the Implementation Status Section", draft-sheffer- running-code-02 (work in progress), January 2013. [RFC5545] Desruisseaux, B., "Internet Calendaring and Scheduling Core Object Specification (iCalendar)", RFC 5545, September 2009. Kewisch Expires April 18, 2014 [Page 26] Internet-Draft jCard October 2013 [RFC6321] Daboo, C., Douglass, M., and S. Lees, "xCal: The XML Format for iCalendar", RFC 6321, August 2011. [RFC6351] Perreault, S., "xCard: vCard XML Representation", RFC 6351, August 2011. [calconnect-artifacts] The Calendaring and Scheduling Consortium, "Code Artifacts and Schemas", , . Appendix A. ABNF Schema Below is an ABNF schema as per [RFC5234] for vCard in JSON. ABNF Symbols not described here are taken from [RFC4627]. The schema is non-normative and given for reference only. The numeric section numbers given in the comments refer to section in [RFC6350]. 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 [RFC6350]. Additional schemas may be available on the internet at [calconnect-artifacts]. ; A jCard object uses the name "vcard" and a properties array. ; Restrictions to which properties and may be specified are to ; be taken from RFC6350. jcardobject = begin-array DQUOTE component-name DQUOTE value-separator properties-array end-array ; A jCard 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 propery-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. Kewisch Expires April 18, 2014 [Page 27] Internet-Draft jCard October 2013 property-value = simple-prop-value / structured-prop-value simple-prop-value = string / number / true / false structured-prop-value = begin-array [ structured-element *(value-separator structured-element) ] end-array ; Each structured element may have multiple values if ; semantically allowed structured-element = simple-prop-value / structured-multi-prop structured-multi-prop = begin-array [ simple-prop-value *(value-separator simple-prop-value) ] end-array ; The jCard params-object is a JSON object which 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-separtor 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 = "text" / "uri" / "date" / "time" / "date-time" / "boolean" / "integer" / "float" / "utc-offset" / "language-tag" / x-type ; Property, parameter and type names MUST be lowercase. Additional ; semantic restrictions apply as described by this document and ; RFC6350. component-name = lowercase-name property-name = lowercase-name param-name = lowercase-name x-type = lowercase-name lowercase-name = 1*(%x61-7A / DIGIT / "-") Appendix B. Examples This section contains an example of a vCard object with its jCard representation. Kewisch Expires April 18, 2014 [Page 28] Internet-Draft jCard October 2013 B.1. Example: vCard of the author of RFC6350 B.1.1. vCard Data BEGIN:VCARD VERSION:4.0 FN:Simon Perreault N:Perreault;Simon;;;ing. jr,M.Sc. BDAY:--0203 ANNIVERSARY:20090808T1430-0500 GENDER:M LANG;PREF=1:fr LANG;PREF=2:en ORG;TYPE=work:Viagenie ADR;TYPE=work:;Suite D2-630;2875 Laurier; Quebec;QC;G1V 2M2;Canada TEL;VALUE=uri;TYPE="work,voice";PREF=1:tel:+1-418-656-9254;ext=102 TEL;VALUE=uri;TYPE="work,cell,voice,video,text":tel:+1-418-262-6501 EMAIL;TYPE=work:simon.perreault@viagenie.ca GEO;TYPE=work:geo:46.772673,-71.282945 KEY;TYPE=work;VALUE=uri: http://www.viagenie.ca/simon.perreault/simon.asc TZ:-0500 URL;TYPE=home:http://nomis80.org END:VCARD B.1.2. jCard Data ["vcard", [ ["version", {}, "text", "4.0"], ["fn", {}, "text", "Simon Perreault"], ["n", {}, "text", ["Perreault", "Simon", "", "", ["ing. jr", "M.Sc."]] ], ["bday", {}, "date-and-or-time", "--02-03"], ["anniversary", {}, "date-and-or-time", "2009-08-08T14:30:00-05:00" ], ["gender", {}, "text", "M"], ["lang", { "pref": "1" }, "language-tag", "fr"], ["lang", { "pref": "2" }, "language-tag", "en"], ["org", { "type": "work" }, "text", "Viagenie"], Kewisch Expires April 18, 2014 [Page 29] Internet-Draft jCard October 2013 ["adr", { "type": "work" }, "text", [ "", "Suite D2-630", "2875 Laurier", "Quebec", "QC", "G1V 2M2", "Canada" ] ], ["tel", { "type": ["work", "voice"], "pref": "1" }, "uri", "tel:+1-418-656-9254;ext=102" ], ["tel", { "type": ["work", "cell", "voice", "video", "text"] }, "uri", "tel:+1-418-262-6501" ], ["email", { "type": "work" }, "text", "simon.perreault@viagenie.ca" ], ["geo", { "type": "work" }, "uri", "geo:46.772673,-71.282945"], ["key", { "type": "work" }, "uri", "http://www.viagenie.ca/simon.perreault/simon.asc" ], ["tz", {}, "utc-offset", "-05:00"], ["url", { "type": "home" }, "uri", "http://nomis80.org"] ] ] Appendix C. Change History (to be removed prior to publication as an RFC) draft-kewisch-vcard-in-json-01 * Added ABNF and improved references in date/time related sections Kewisch Expires April 18, 2014 [Page 30] Internet-Draft jCard October 2013 * Changes to wording in "vCard Stream" section * Changes to wording about VALUE parameter when converting to vCard * Corrected missing "type" parameter and separator in example * Minor wording corrections draft-ietf-jcardcal-jcard-00 * Pubication as a WG draft draft-ietf-jcardcal-jcard-01 * Changed grouping syntax to use new GROUP parameter and added respective IANA section * Added timestamp and date-and-or-time types instead of converting them from date/time/date-time * Added a further sentence on preprocessing and escaping to clarify that JSON escaping must be used * Described how to handle structured text values and structured text components with multiple values. * Corrections and additions to the ABNF Section, adaptions to example draft-ietf-jcardcal-jcard-02 * Made more clear that complete representation is not mandatory * Added sheffer-running-code section * Changed handling of unknown property parameter types * Minor corrections to sections regarding dates, fixing typos draft-ietf-jcardcal-jcard-03 * Add LABEL property example and description * Added acknowledgements * More typos fixed Kewisch Expires April 18, 2014 [Page 31] Internet-Draft jCard October 2013 draft-ietf-jcardcal-jcard-04 * Added reference to rfc6868 * Various editorial changes per jcardcal issue tracker * Resolved a few MAY/SHOULD conflicts * Put the VERSION property into its own section * Improved GROUP/UNKNOWN registrations by only putting vcard related information into the registration template * Removed vcard stream construct. * Added reference to RFC6868 for both directions * Corrected some examples and ABNF draft-ietf-jcardcal-jcard-05 * Updated UNKNOWN registration text to match with jCal text. draft-ietf-jcardcal-jcard-06 * Various editoral changes based on the IETF reviews. Please see http://trac.tools.ietf.org/wg/jcardcal/trac/ for details. draft-ietf-jcardcal-jcard-07 * More editoral changes based on the IETF reviews. Please see http://trac.tools.ietf.org/wg/jcardcal/trac/ for details. * Merged examples for single/multi-valued properties * Move IANA registrations for GROUP and UNKNOWN to the end of the document * Corrected a few examples, e.g. use of "lang" vs "language" or missing version property. Author's Address Kewisch Expires April 18, 2014 [Page 32] Internet-Draft jCard October 2013 Philipp Kewisch Mozilla Corporation 650 Castro Street, Suite 300 Mountain View, CA 94041 USA EMail: mozilla@kewis.ch URI: http://www.mozilla.org/ Kewisch Expires April 18, 2014 [Page 33]