ISO/IEC 24752-8:2018

INTERNATIONAL ISO/IEC
STANDARD 24752-8
First edition
2018-04
Information technology — User
interfaces — Universal remote
console —
Part 8:
User interface resource framework
Technologies de l'information — Interfaces utilisateur —
Télécommande universelle —
Partie 8: Cadre de ressources pour les interfaces utilisateur
Reference number
ISO/IEC 24752-8:2018(E)
©
ISO/IEC 2018

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ISO/IEC 24752-8:2018(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO/IEC 2018
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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Published in Switzerland
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ISO/IEC 24752-8:2018(E)

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Conformance . 3
5 Use cases (informative) . 4
5.1 General . 4
5.2 User interface localisation. 4
5.3 User interface personalisation . 4
5.4 User interface accessibility . 4
5.5 User interface responsiveness . 5
5.6 User interface settings . 5
6 Workflow model (informative) . 5
6.1 General . 5
6.2 Storing and retrieving a user-context . 5
6.3 Storing and retrieving a task-context . 5
6.4 Storing and retrieving an equipment-context . . 6
6.5 Storing and retrieving an environment-context . 6
6.6 Describing resources . 6
6.7 Finding and retrieving matching resources . 7
6.8 Describing user interface settings . 8
6.9 Finding and retrieving matching user interface settings . 8
7 REST interfaces for services . 8
7.1 General . 8
7.1.1 REST architecture (informative) . 8
7.1.2 Request and response parameters . 9
7.1.3 Response codes . 9
7.1.4 Authentication .10
7.1.5 Other general requirements .10
7.2 User-context .10
7.2.1 General.10
7.2.2 CREATE user-context (mandatory) .12
7.2.3 GET user-context (mandatory) .13
7.2.4 UPDATE user-context (mandatory) .14
7.2.5 DELETE user-context (optional) .14
7.2.6 GET user-context-list (mandatory) . .15
7.3 Task-context .17
7.3.1 General.17
7.3.2 CREATE task-context (mandatory) .17
7.3.3 GET task-context (mandatory) .18
7.3.4 UPDATE task-context (mandatory) .19
7.3.5 DELETE task-context (optional) .20
7.3.6 GET task-context-list (mandatory) .20
7.4 Equipment-context .22
7.4.1 General.22
7.4.2 CREATE equipment-context (mandatory) .22
7.4.3 GET equipment-context (mandatory) .23
7.4.4 UPDATE equipment-context (mandatory) .24
7.4.5 DELETE equipment-context (optional) .25
7.4.6 GET equipment-context-list (mandatory) .26
7.5 Environment-context.28
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7.5.1 General.28
7.5.2 CREATE environment-context (mandatory) .28
7.5.3 GET environment-context (mandatory) .29
7.5.4 UPDATE environment-context (mandatory) .30
7.5.5 DELETE environment-context (optional) .31
7.5.6 GET environment-context-list (mandatory) .32
7.6 Resource .34
7.6.1 General.34
7.6.2 CREATE resource (mandatory) .34
7.6.3 GET resource-by-ID (mandatory) .35
7.6.4 GET resource-from-listing (mandatory) .36
7.6.5 UPDATE resource (optional) .37
7.6.6 DELETE resource (optional) .38
7.7 Resource-description .38
7.7.1 General.38
7.7.2 CREATE resource-description (mandatory) .39
7.7.3 GET resource-description-by-ID (mandatory) .40
7.7.4 GET resource-description-from-listing (mandatory) .41
7.7.5 UPDATE resource-description (mandatory) .41
7.7.6 DELETE resource-description (optional) .42
7.8 Listing .43
7.8.1 General.43
7.8.2 CREATE listing (mandatory) .43
7.8.3 GET listing (mandatory) .44
7.8.4 DELETE listing (optional) .45
7.8.5 CONFIRM user-rating (optional) .46
8 Security considerations.47
Annex A (normative) Mapping for XML .48
Annex B (normative) Mapping for JSON .67
Bibliography .86
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ISO/IEC 24752-8:2018(E)

Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are
members of ISO or IEC participate in the development of International Standards through technical
committees established by the respective organization to deal with particular fields of technical
activity. ISO and IEC technical committees collaborate in fields of mutual interest. Other international
organizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the
work. In the field of information technology, ISO and IEC have established a joint technical committee,
ISO/IEC JTC 1.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for
the different types of document should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject
of patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent
rights. Details of any patent rights identified during the development of the document will be in the
Introduction and/or on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following
URL: www .iso .org/ iso/ foreword .html.
This document was prepared by Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 35, User interfaces.
A list of all parts in the ISO/IEC 24752 series can be found on the ISO website.
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Introduction
Adaptive user interfaces change their presentation and behaviour according to the specific context
of use, including the user's needs and preferences, their devices and environmental parameters. Such
changes are to be considered at development time. At runtime, the user interface can take all aspects of
the context of use into consideration.
Changes at runtime often require that some custom-tailored user interface resources be prepared
in advance. Examples include captions and audio description for videos, alternate text for images, a
simplified version of an online banking app, a sign language video explaining how to take HDR photos on
an online camera guide, and a help item in easy language for a tax report software. Such user interface
resources will often be made available by third parties, for example human factors experts, user groups
and individual users. They will upload and describe these resources on resource services from which
adaptive user interface implementations can discover and retrieve them at runtime.
To make this process work, two aspects need standardization: First, user interface resources should
be clearly and unambiguously described so that they can be discovered at runtime. Second, resource
services hosting these user interface resources should be discoverable and have a clearly described
interface for querying and retrieving user interface resources.
This document addresses both aspects in a flexible way. It specifies syntax and semantics for a RESTful
resource service interface while not restricting the clients in using whatever vocabulary and terms
they choose for the description of user interface resources. Since HTTP is used as the most common
REST implementation, this document defines a light-weight protocol that can be used on virtually all
user interface platforms, including web browsers, mobile apps and software agents.
NOTE Though this document is part of the Universal Remote Console (URC) framework, it can be used
independently from the other URC technologies. In particular, a user interface implementation can benefit from
a user interface resource service without being connected to a URC target and without employing the user
interface socket approach.
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INTERNATIONAL STANDARD ISO/IEC 24752-8:2018(E)
Information technology — User interfaces — Universal
remote console —
Part 8:
User interface resource framework
1 Scope
This document defines a RESTful protocol for the provision and delivery of resources that are related to
user interface adaptation based on context of use.
This document addresses requirements and recommendations for the following services:
— user-context service;
— task-context service;
— equipment-context service;
— environment-context service;
— resource service;
— resource-description service;
— matching service (for finding appropriate resources based on specific contexts and other match
criteria).
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO/IEC 10646, Universal Multiple-Octet Coded Character Set (UCS)
1)
IETF RFC 2046 , Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types
2)
IETF RFC 3986 , Uniform Resource Identifier (URI): Generic Syntax
3)
IETF RFC 7159 , The JavaScript Object Notation (JSON) Data Interchange Format
4)
IETF RFC 7230 , Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing
5)
IETF RFC 7231 , Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content
1) November 1996, https:// tools .ietf .org/ html/ rfc2046.
2) January 2005, https:// tools .ietf .org/ html/ rfc3986.
3) March 2014, https:// tools .ietf .org/ html/ rfc7159.
4) June 2014, https:// tools .ietf .org/ html/ rfc7230.
5) June 2014, https:// tools .ietf .org/ html/ rfc7231.
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6)
W3C XML 1.0 , Extensible Markup Language (XML) 1.0, W3C Recommendation
7)
W3C XML Schema Part 1 , Structures, W3C Recommendation
8)
W3C XML Schema Part 2 , Datatypes, W3C Recommendation
3 Terms and definitions
For the purposes of this document, the following terms, definitions, symbols and abbreviated terms apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http:// www .electropedia .org/
— ISO Online browsing platform: available at http:// www .iso .org/ obp
3.1 Context of use
3.1.1
context of use
use context
users, tasks, equipment (hardware, software and materials), and the physical and social environments
in which a product is used
[SOURCE: ISO 9241-11:1998, 3.5]
3.1.2
user-context
part of the context of use that describes aspects of an individual user interacting with an ICT system
3.1.3
task-context
part of the context of use that describes aspects of the task done by a user in interacting with an
ICT system
3.1.4
equipment-context
part of the context of use that describes aspects of the equipment (hardware, software and materials)
used by a user to interact with an ICT system
3.1.5
environment-context
part of the context of use that describes aspects of the physical and social environments in which a user
interacts with an ICT system
3.2 Resources
3.2.1
resource
user interface resource
object that is used as an entity or to support decision making in the construction of a concrete user
interface
[SOURCE: ISO/IEC 24752-1:2014, 3.31¸modified — the alternative term ‘user interface resource’ has
been added and an EXAMPLE and Note to entry have been removed]
6) https:// www .w3 .org/ TR/ xml/ .
7) https:// www .w3 .org/ TR/ xmlschema -1/ .
8) https:// www .w3 .org/ TR/ xmlschema -2/ .
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3.2.2
property
aspect of a context or resource used to describe the context or resource
Note 1 to entry: In this document, properties are represented as key-value pairs.
3.2.3
user-rating
explicit or implicit statement of an individual user about the degree of personal preference for a
particular resource or resource description
Note 1 to entry: In this document, user-ratings are represented as float values between −1.0 and 1.0. The value
−1.0 represents the highest degree of dislike, 0.0 represents no preference (neutral position), and 1.0 represents
the highest degree of like.
3.3 Services
3.3.1
service
server offering RESTful operations for the management of REST resources
3.3.2
matching service
service that manages listings
3.3.3
listing
ordered list of resource descriptions that match specific criteria for user-context, task-context,
equipment-context, environment-context and resource description properties
3.4 Representational State Transfer
3.4.1
Representational State Transfer
REST
paradigm for an HTTP-based protocol that is built upon HTTP methods as operations and URIs as
resources
Note 1 to entry: Representational State Transfer was first introduced by Fielding (2000).
3.4.2
RESTful
conforming to the constraints of REST
3.4.3
REST resource
data object that is addressable with a URI and that can be manipulated via HTTP verbs
4 Conformance
A user-context service conforms to this document if all of the following is true:
— It complies with 7.1 and 7.2.
— It provides appropriate mappings for XML (A.1, A.2) and JSON (B.1, B.2).
A task-context service conforms to this document if all of the following is true:
— It complies with 7.1 and 7.3.
— It provides appropriate mappings for XML (A.1, A.3) and JSON (B.1, B.3).
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An equipment-context service conforms to this document if all of the following is true:
— It complies with 7.1 and 7.4.
— It provides appropriate mappings for XML (A.1, A.4) and JSON (B.1, B.4).
An environment-context service conforms to this document if all of the following is true:
— It complies with 7.1 and 7.5.
— It provides appropriate mappings for XML (A.1, A.5) and JSON (B.1, B.5).
A resource service conforms to this document if all of the following is true:
— It complies with 7.1 and 7.6.
— It provides appropriate mappings for XML (A.1, A.6) and JSON (B.1, B.6).
A resource-description service conforms to this document if all of the following is true:
— It complies with 7.1 and 7.7.
— It provides appropriate mappings for XML (A.1, A.7) and JSON (B.1, B.7).
A matching service conforms to this document if all of the following is true:
— It complies with 7.1 and 7.8.
— It provides appropriate mappings for XML (A.1, A.8) and JSON (B.1, B.8).
5 Use cases (informative)
5.1 General
This clause contains a set of use cases for illustration of possible applications for this document. The set
of use cases is not exhaustive, and does not limit the applicability of this document.
5.2 User interface localisation
— User interface localisation: A user interface label or icon is replaced at runtime by a supplementary
label or icon from a resource service.
— User interface augmentation: A sign language video from a resource service is added to a user
interface at runtime for the purpose of making the user interface more accessible for a deaf user.
5.3 User interface personalisation
— A browser loads an alternative style sheet from a resource service for the purpose of personalisation
of a specific webpage.
— A smart-home device loads an old-style design of light controls from a resource service as a web
component to replace the default design.
— A simplified user interface of an online banking application is loaded at runtime for a user with a
mild cognitive disability.
5.4 User interface accessibility
— A browser downloads a long image description from a resource service for the purpose of allowing
the user to listen to the image description via their screenreader.
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— A video player downloads a third-party caption file from a resource service, for the purpose of
displaying them with the rendition of a video from the Internet that had no captions attached.
— A video player downloads a third-party audio description track from a resource service, for the
purpose of playing it in place of the default audio track of a video from the Internet that included no
audio description.
5.5 User interface responsiveness
— At runtime, a drop-down menu in a webpage is replaced by a group of large graphical push buttons
to make it easier to be operated on a Tablet with touch screen.
5.6 User interface settings
— An operating system retrieves and activates a set of user interface settings that accommodates
the needs and preferences of an individual user although this user has never used the operating
system before.
— An application (e.g. an editor) finds a suitable configuration for an individual user although the user
has never used the application before.
6 Workflow model (informative)
6.1 General
This document supports applications (in the role of a client of a service) in operating with user-
contexts, task-contexts, equipment-contexts, environment-contexts, resources, resource descriptions
and listings.
The following subsections describe typi
...