Calendaring extensions R. Stepanek
Internet-Draft FastMail
Intended status: Standards Track M. Loffredo
Expires: July 20, 2020 IIT-CNR
January 17, 2020

JSContact: A JSON representation of contact data


This specification defines a data model and JSON representation of contact card information that can be used for data storage and exchange in address book or directory applications. It aims to be an alternative to the vCard data format and to be unambiguous, extendable and simple to process. In contrast to the JSON-based jCard format, it is not a direct mapping from the vCard data model and expands semantics where appropriate.

Status of This Memo

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This Internet-Draft will expire on July 20, 2020.

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Table of Contents

1. Introduction

This document defines a data model for contact card data normally used in address book or directory applications and services. It aims to be an alternative to the vCard data format [RFC6350] and to provide a JSON-based standard representation of contact card data.

The key design considerations for this data model are as follows:

The representation of this data model is defined in the I-JSON format [RFC7493], which is a strict subset of the JavaScript Object Notation (JSON) Data Interchange Format [RFC8259]. Using JSON is mostly a pragmatic choice: its widespread use makes JSCard easier to adopt, and the availability of production-ready JSON implementations eliminates a whole category of parser-related interoperability issues.

1.1. Relation to the xCard and jCard formats

The xCard [RFC6351] and jCard [RFC7095] specifications define alternative representations for vCard data, in XML and JSON format respectively. Both explicitly aim to not change the underlying data model. Accordingly, they are regarded as equal to vCard in the context of this document.

1.2. Terminology

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

1.3. Vendor-specific Property Extensions and Values

Vendors MAY add additional properties to JSContact objects to support their custom features. The names of these properties MUST be prefixed with a domain name controlled by the vendor to avoid conflict, e.g. "".

Some JSContact properties allow vendor-specific value extensions. If so, vendor-specific values MUST be prefixed with a domain name controlled by the vendor, e.g. "".

Vendors are strongly encouraged to register any new property values or extensions that are useful to other systems as well, rather than using a vendor-specific prefix.

2. JSCard

MIME type: application/jscontact+json;type=jscard

A JSCard object stores information about a person, organization or company.

2.1. Metadata properties

2.1.1. uid

Type: String (mandatory).

An identifier, used to associate the object as the same across different systems, addressbooks and views. [RFC4122] describes a range of established algorithms to generate universally unique identifiers (UUID), and the random or pseudo-random version is recommended. For compatibility with [RFC6350] UIDs, implementations MUST accept both URI and free-form text.

2.1.2. prodId

Type: String (optional).

The identifier for the product that created the JSCard object.

2.1.3. updated

Type: String (mandatory).

The date and time when the data in this JSCard object was last modified. The timestamp MUST be formatted as specified in [RFC3339].

2.1.4. kind

Type: String (optional). The kind of the entity the Card represents.

The value MUST be either one of the following values, registered in a future RFC, or a vendor-specific value:

2.1.5. relatedTo

Type: String[Relation] (optional).

Relates the object to other JSCard objects. This is represented as a map of the URI (or single text value) of the related objects to a possibly empty set of relation types. The Relation object has the following properties:

Note, the Relation object only has one property; it is specified as an object with a single property to allow for extension in the future.

2.2. Name and Organization properties

2.2.1. fullName

Type: LocalizedString (optional).

The full name (e.g. the personal name and surname of an individual, the name of an organization) of the entity represented by this card.

2.2.2. name

Type: NameComponent[] (optional).

The name components of the name of the entity represented by this JSCard. Name components SHOULD be ordered such that their values joined by whitespace produce a valid full name of this entity.

A NameComponent has the following properties:

2.2.3. organization

Type: LocalizedString[] (optional).

The company or organization name and units associated with this card. The first entry in the list names the organization, and any following entries name organizational units.

2.2.4. jobTitle

Type : LocalizedString[] (optional).

The job title(s) or functional position(s) of the entity represented by this card.

2.2.5. role

Type : LocalizedString[] (optional).

The role(s), function(s) or part(s) played in a particular situation by the entity represented by this card. In contrast to a job title, the roles might differ for example in project contexts.

2.3. Contact and Resource properties

2.3.1. emails

Type: Resource[] (optional).

An array of Resource objects where the values are URLs in the [RFC6068] mailto scheme or free-text email addresses. Types are:

2.3.2. phones

Type: Resource[] (optional).

An array of Resource objects where the values are URIs scheme or free-text phone numbers. Typical URI schemes are the [RFC3966] tel or [RFC3261] sip schemes, but any URI scheme is allowed. Resource types are:

The following labels are pre-defined for phone resources:

2.3.3. online

Type: Resource[] (optional).

An array of Resource objects where the values are URIs or usernames associated with the card for online services. Types are:

2.3.4. preferredContactMethod

Type : String (optional)

Defines the preferred contact method or resource with additional information about this card. The value MUST be the property name of one of the Resource lists: emails, phones, online, other.

2.3.5. preferredContactLanguages

Type : String[ContactLanguage[]] (optional)

Defines the preferred languages for contacting the entity associated with this card. The keys in the object MUST be [RFC5646] language tags. The values are a (possibly empty) list of contact language preferences for this language. Also see the definition of the VCARD LANG property (Section 6.4.4., [RFC6350]).

A ContactLanguage object has the following properties:

A valid ContactLanguage object MUST have at least one of its properties set.

2.4. Address and Location properties

2.4.1. addresses

Type: Address[] (optional).

An array of Address objects, containing physical locations. An Address object has the following properties:

2.5. Additional properties

2.5.1. anniversaries

Type : Anniversary[] (optional).

Memorable dates and events for the entity represented by this card. An Anniversary object has the following properties:

2.5.2. personalInfo

Type: PersonalInformation[] (optional).

A list of personal information about the entity represented by this card. A PersonalInformation object has the following properties:

2.5.3. notes

Type: LocalizedString[] (optional).

Arbitrary notes about the entity represented by this card.

2.5.4. categories

Type: String[] (optional). A list of free-text or URI categories that relate to the card.

2.6. Common JSCard types

2.6.1. LocalizedString

A LocalizedString object has the following properties:

2.6.2. Resource

A Resource object has the following properties:

3. JSCardGroup

MIME type: application/jscontact+json;type=jscardgroup

A JSCardGroup object represents a named set of JSCards.

3.1. Properties

3.1.1. uid

Type : String (mandatory).

A globally unique identifier. The same requirements as for the JSCard uid property apply.

3.1.2. name

Type: String (optional).

The user-visible name for the group, e.g. "Friends". This may be any UTF-8 string of at least 1 character in length and maximum 255 octets in size. The same name may be used by two different groups.

3.1.3. cards

Type : JSCard[] (mandatory). The cards in the group. Implementations MUST preserve the order of list entries.

4. Implementation Status

NOTE: Please remove this section and the reference to [RFC7942] prior to publication as an RFC. This section records the status of known implementations of the protocol defined by this specification at the time of posting of this Internet-Draft, and is based on a proposal described in [RFC7942]. The description of implementations in this section is intended to assist the IETF in its decision processes in progressing drafts to RFCs. Please note that the listing of any individual implementation here does not imply endorsement by the IETF. Furthermore, no effort has been spent to verify the information presented here that was supplied by IETF contributors. This is not intended as, and must not be construed to be, a catalog of available implementations or their features. Readers are advised to note that other implementations may exist. According to [RFC7942], "this will allow reviewers and working groups to assign due consideration to documents that have the benefit of running code, which may serve as evidence of valuable experimentation and feedback that have made the implemented protocols more mature. It is up to the individual working groups to use this information as they see fit".

4.1. IIT-CNR/

5. IANA Considerations


6. Security Considerations


7. References

7.1. Normative References

[RFC2046] Freed, N. and N. Borenstein, "Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types", RFC 2046, DOI 10.17487/RFC2046, November 1996.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997.
[RFC4122] Leach, P., Mealling, M. and R. Salz, "A Universally Unique IDentifier (UUID) URN Namespace", RFC 4122, DOI 10.17487/RFC4122, July 2005.
[RFC5646] Phillips, A. and M. Davis, "Tags for Identifying Languages", BCP 47, RFC 5646, DOI 10.17487/RFC5646, September 2009.
[RFC5870] Mayrhofer, A. and C. Spanring, "A Uniform Resource Identifier for Geographic Locations ('geo' URI)", RFC 5870, DOI 10.17487/RFC5870, June 2010.
[RFC6350] Perreault, S., "vCard Format Specification", RFC 6350, DOI 10.17487/RFC6350, August 2011.
[RFC6351] Perreault, S., "xCard: vCard XML Representation", RFC 6351, DOI 10.17487/RFC6351, August 2011.
[RFC7095] Kewisch, P., "jCard: The JSON Format for vCard", RFC 7095, DOI 10.17487/RFC7095, January 2014.
[RFC7493] Bray, T., "The I-JSON Message Format", RFC 7493, DOI 10.17487/RFC7493, March 2015.
[RFC7942] Sheffer, Y. and A. Farrel, "Improving Awareness of Running Code: The Implementation Status Section", BCP 205, RFC 7942, DOI 10.17487/RFC7942, July 2016.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017.
[RFC8259] Bray, T., "The JavaScript Object Notation (JSON) Data Interchange Format", STD 90, RFC 8259, DOI 10.17487/RFC8259, December 2017.

7.2. Informative References

[RFC3261] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A., Peterson, J., Sparks, R., Handley, M. and E. Schooler, "SIP: Session Initiation Protocol", RFC 3261, DOI 10.17487/RFC3261, June 2002.
[RFC3339] Klyne, G. and C. Newman, "Date and Time on the Internet: Timestamps", RFC 3339, DOI 10.17487/RFC3339, July 2002.
[RFC3966] Schulzrinne, H., "The tel URI for Telephone Numbers", RFC 3966, DOI 10.17487/RFC3966, December 2004.
[RFC6068] Duerst, M., Masinter, L. and J. Zawinski, "The 'mailto' URI Scheme", RFC 6068, DOI 10.17487/RFC6068, October 2010.
[RFC6473] Saint-Andre, P., "vCard KIND:application", RFC 6473, DOI 10.17487/RFC6473, December 2011.
[RFC6474] Li, K. and B. Leiba, "vCard Format Extensions: Place of Birth, Place and Date of Death", RFC 6474, DOI 10.17487/RFC6474, December 2011.
[RFC6715] Cauchie, D., Leiba, B. and K. Li, "vCard Format Extensions: Representing vCard Extensions Defined by the Open Mobile Alliance (OMA) Converged Address Book (CAB) Group", RFC 6715, DOI 10.17487/RFC6715, August 2012.
[RFC6869] Salgueiro, G., Clarke, J. and P. Saint-Andre, "vCard KIND:device", RFC 6869, DOI 10.17487/RFC6869, February 2013.
[RFC8605] Hollenbeck, S. and R. Carney, "vCard Format Extensions: ICANN Extensions for the Registration Data Access Protocol (RDAP)", RFC 8605, DOI 10.17487/RFC8605, May 2019.

Authors' Addresses

Robert Stepanek FastMail PO Box 234, Collins St West Melbourne, VIC 8007 Australia EMail:
Mario Loffredo IIT-CNR Via Moruzzi,1 Pisa, 56124 Italy EMail: