Internet Engineering Task Force A. Wright, Ed.
Internet-Draft
Intended status: Informational G. Luff
Expires: April 16, 2017 October 13, 2016
JSON Hyper-Schema: A Vocabulary for Hypermedia Annotation of JSON
draft-wright-json-schema-hyperschema-00
Abstract
JSON Schema is a JSON based format for defining the structure of JSON
data. This document specifies hyperlink- and hypermedia-related
keywords of JSON Schema for annotating JSON documents with hyperlinks
and instructions for processing and manipulating remote JSON
resources through hypermedia environments like HTTP.
Note to Readers
The issues list for this draft can be found at <https://github.com/
json-schema-org/json-schema-spec/issues>.
For additional information, see <http://json-schema.org/>.
To provide feedback, use this issue tracker, the communication
methods listed on the homepage, or email the document editors.
Status of This Memo
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This Internet-Draft will expire on April 16, 2017.
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Copyright Notice
Copyright (c) 2016 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
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described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions and Terminology . . . . . . . . . . . . . . . . . 3
3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 3
4. Schema keywords . . . . . . . . . . . . . . . . . . . . . . . 5
4.1. base . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4.2. links . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4.3. media . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4.3.1. Properties of "media" . . . . . . . . . . . . . . . . 7
4.3.2. Example . . . . . . . . . . . . . . . . . . . . . . . 7
4.4. readOnly . . . . . . . . . . . . . . . . . . . . . . . . 8
5. Link Description Object . . . . . . . . . . . . . . . . . . . 8
5.1. href . . . . . . . . . . . . . . . . . . . . . . . . . . 9
5.1.1. URI Templating . . . . . . . . . . . . . . . . . . . 9
5.2. rel . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
5.2.1. Security Considerations for "self" links . . . . . . 13
5.3. title . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5.4. targetSchema . . . . . . . . . . . . . . . . . . . . . . 15
5.4.1. Security Considerations for "targetSchema" . . . . . 15
5.5. mediaType . . . . . . . . . . . . . . . . . . . . . . . . 16
5.5.1. Security concerns for "mediaType" . . . . . . . . . . 17
5.6. Submission Form Properties . . . . . . . . . . . . . . . 18
5.6.1. method . . . . . . . . . . . . . . . . . . . . . . . 18
5.6.2. encType . . . . . . . . . . . . . . . . . . . . . . . 18
5.6.3. schema . . . . . . . . . . . . . . . . . . . . . . . 19
6. References . . . . . . . . . . . . . . . . . . . . . . . . . 19
6.1. Normative References . . . . . . . . . . . . . . . . . . 19
6.2. Informative References . . . . . . . . . . . . . . . . . 20
Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 21
Appendix B. Change Log . . . . . . . . . . . . . . . . . . . . . 21
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 22
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1. Introduction
JSON Schema is a JSON based format for defining the structure of JSON
data. This document specifies hyperlink- and hypermedia-related
keywords of JSON Schema.
The term JSON Hyper-Schema is used to refer to a JSON Schema that
uses these keywords.
This specification will use the terminology defined by the JSON
Schema core specification [json-schema]. It is advised that readers
have a copy of this specification.
2. Conventions and Terminology
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 RFC 2119 [RFC2119].
The terms "schema", "instance", "property" and "item" are to be
interpreted as defined in the JSON Schema core specification
[json-schema].
3. Overview
This document describes how JSON Schema can be used to define
hyperlinks on instance data. It also defines how to provide
additional information required to interpret JSON data as rich
multimedia documents.
As with all JSON Schema keywords, all the keywords described in the
"Schema Keywords" section are optional. The minimal valid JSON
Hyper-schema is the blank object.
Here is an example JSON Schema defining hyperlinks, and providing a
multimedia interpretation for the "imgData" property:
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{
"title": "Written Article",
"type": "object",
"properties": {
"id": {
"title": "Article Identifier",
"type": "number",
"readOnly": true
},
"title": {
"title": "Article Title",
"type": "string"
},
"authorId": {
"type": "integer"
},
"imgDataPng": {
"title": "Article Illustration (thumbnail)",
"type": "string",
"media": {
"binaryEncoding": "base64",
"type": "image/png"
}
}
},
"required" : ["id", "title", "authorId"],
"links": [
{
"rel": "self",
"href": "/article{?id}"
},
{
"rel": "author",
"href": "/user?id={authorId}"
}
]
}
This example schema defines the properties of the instance. For the
"imgData" property, it specifies that that it should be
base64-decoded and the resulting binary data treated as a PNG image.
It also defines link relations for the instance, with URIs
incorporating values from the instance. [[CREF1: "id" probably
should not normally be a required keyword, since new instances will
have an unknown "id" property until is it assigned by the server.
However, this property is used in a link, and without it, multiple
different instances would be given the same rel=self URI!]]
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An example of a JSON instance described by the above schema might be:
{
"id": 15,
"title": "Example data",
"authorId": 105,
"imgData": "iVBORw...kJggg=="
}
The base-64 data has been abbreviated for readability.
4. Schema keywords
4.1. base
If present, this keyword is resolved against the current URI base
that the entire instance is found within, and sets the new URI base
for URI references within the instance. It is therefore the first
URI Reference resolved, regardless of which order it was found in.
The URI is computed from the provided URI template using the same
process described for the "href" (Section 5.1) property of a Link
Description Object.
An example of a JSON schema using "base":
{
"base": "/object/{id}",
"links": [
{
"rel": "self",
"href": ""
},
{
"rel": "next",
"href": "{next_id}"
}
]
}
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An example of a JSON instance using this schema to produce rel="self"
and rel="next" links:
{
"id": "41",
"next_id": "42"
}
If the document URI is <http://example.com/?id=41>, then the new URI
base becomes <http://example.com/object/41>
Resolving the two Link Description Objects against this URI base
creates two links exactly equivelant to these absolute-form HTTP Link
headers:
o Link: <http://example.com/object/41>;rel=self
o Link: <http://example.com/object/42>;rel=next
4.2. links
The "links" property of schemas is used to associate Link Description
Objects with instances. The value of this property MUST be an array,
and the items in the array must be Link Description Objects, as
defined below.
An example schema using the "links" keyword could be:
{
"title": "Schema defining links",
"links": [
{
"rel": "self",
"href": "{id}"
},
{
"rel": "parent",
"href": "{parent}"
}
]
}
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4.3. media
The "media" property indicates that this instance contains non-JSON
data encoded in a JSON string. It describes the type of content and
how it is encoded.
The value of this property MUST be an object. The value of this
property SHOULD be ignored if the instance described is not a string.
4.3.1. Properties of "media"
The value of the "media" keyword MAY contain any of the following
properties:
4.3.1.1. binaryEncoding
If the instance value is a string, this property defines that the
string SHOULD be interpreted as binary data and decoded using the
encoding named by this property. RFC 2045, Sec 6.1 [RFC2045] lists
the possible values for this property.
4.3.1.2. type
The value of this property must be a media type, as defined by RFC
2046 [RFC2046]. This property defines the media type of instances
which this schema defines.
If the "binaryEncoding" property is not set, but the instance value
is a string, then the value of this property SHOULD specify a text
document type, and the character set SHOULD be the character set into
which the JSON string value was decoded (for which the default is
Unicode).
4.3.2. Example
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Here is an example schema, illustrating the use of "media":
{
"type": "string",
"media": {
"binaryEncoding": "base64",
"type": "image/png"
}
}
Instances described by this schema should be strings, and their
values should be interpretable as base64-encoded PNG images.
Another example:
{
"type": "string",
"media": {
"mediaType": "text/html"
}
}
Instances described by this schema should be strings containing HTML,
using whatever character set the JSON string was decoded into
(default is Unicode).
4.4. readOnly
If it has a value of boolean true, this keyword indicates that the
value of the instance is managed exclusively by the server or the
owning authority, and attempts by a user agent to modify the value of
this property are expected to be ignored or rejected by a server.
For example, this property would be used to mark a server-generated
serial number as read-only.
The value of this keyword MUST be a boolean. The default value is
false.
5. Link Description Object
A Link Description Object (LDO) is used to describe a single link
relation from the instance to another resource. A Link Description
Object must be an object.
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The link description format can be used without JSON Schema, and use
of this format can be declared by referencing the normative link
description schema as the schema for the data structure that uses the
links. The URI of the normative link description schema is:
http://json-schema.org/draft-04/links (draft-04 version).
"Form"-like functionality can be defined by use of the "method" and
"schema" keywords, which supplies a schema describing the data to
supply to the server.
5.1. href
The value of the "href" link description property is a template used
to determine the target URI of the related resource. The value of
the instance property MUST be resolved as a URI-reference [RFC3986]
against the base URI of the instance.
This property is REQUIRED.
5.1.1. URI Templating
The value of "href" is to be used as a URI Template, as defined in
RFC 6570 [RFC6570]. However, some special considerations apply:
5.1.1.1. Pre-processing
[[CREF2: This pre-processing section is subject to significant change
in upcoming drafts.]]
The URI Template specification [RFC6570] restricts the set of
characters available for variable names. Property names in JSON,
however, can be any UTF-8 string.
To allow the use of any JSON property name in the template, before
using the value of "href" as a URI Template, the following pre-
processing rules MUST be applied, in order:
5.1.1.1.1. Bracket escaping
The purpose of this step is to allow the use of brackets to percent-
encode variable names inside curly brackets. Variable names to be
escaped are enclosed within rounded brackets, with the close-rounded-
bracket character ")" being escaped as a pair of close-rounded-
brackets "))". Since the empty string is not a valid variable name
in RFC 6570, an empty pair of brackets is replaced with "%65mpty".
The rules are as follows:
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Find the largest possible sections of the text such that:
do not contain an odd number of close-rounded-bracket characters
")" in sequence in that section of the text
are surrounded by a pair of rounded brackets: ( ), where
the surrounding rounded brackets are themselves contained within a
pair of curly brackets: { }
Each of these sections of the text (including the surrounding rounded
brackets) MUST be replaced, according to the following rules:
If the brackets contained no text (the empty string), then they
are replaced with "%65mpty" (which is "empty" with a percent-
encoded "e")
Otherwise, the enclosing brackets are removed, and the inner text
used after the following modifications
all pairs of close-brackets "))" are replaced with a single
close bracket
after that, the text is replaced with its percent-encoded
equivalent, such that the result is a valid RFC 6570 variable
name (note that this requires encoding characters such as "*"
and "!")
5.1.1.1.2. Replacing $
After the above substitutions, if the character "$" (dollar sign)
appears within a pair of curly brackets, then it MUST be replaced
with the text "%73elf" (which is "self" with a percent-encoded "s").
The purpose of this stage is to allow the use of the instance value
itself (instead of its object properties or array items) in the URI
Template, by the special value "%73elf".
5.1.1.1.3. Choice of special-case values
The special-case values of "%73elf" and "%65mpty" were chosen because
they are unlikely to be accidentally generated by either a human or
automated escaping.
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5.1.1.1.4. Examples
For example, here are some possible values for "href", followed by
the results after pre-processing:
+-----------------------+-----------------------+
| Input | Output |
+-----------------------+-----------------------+
| "no change" | "no change" |
| "(no change)" | "(no change)" |
| "{(escape space)}" | "{escape%20space}" |
| "{(escape+plus)}" | "{escape%2Bplus}" |
| "{(escape*asterisk)}" | "{escape%2Aasterisk}" |
| "{(escape(bracket)}" | "{escape%28bracket}" |
| "{(escape))bracket)}" | "{escape%29bracket}" |
| "{(a))b)}" | "{a%29b} |
| "{(a (b)))}" | "{a%20%28b%29} |
| "{()}" | "{%65mpty} |
| "{+$*}" | "{+%73elf*} |
| "{+($)*}" | "{+%24*} |
+-----------------------+-----------------------+
Note that in the final example, because the "+" was outside the
brackets, it remained unescaped, whereas in the fourth example the
"+" was escaped.
5.1.1.2. Values for substitution
After pre-processing, the URI Template is filled out using data from
the instance. To allow the use of any object property (including the
empty string), array index, or the instance value itself, the
following rules are defined:
For a given variable name in the URI Template, the value to use is
determined as follows:
If the variable name is "%73elf", then the instance value itself
MUST be used.
If the variable name is "%65mpty", then the instances's empty-
string ("") property MUST be used (if it exists).
If the instance is an array, and the variable name is a
representation of a non-negative integer, then the value at the
corresponding array index MUST be used (if it exists).
Otherwise, the variable name should be percent-decoded, and the
corresponding object property MUST be used (if it exists).
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5.1.1.2.1. Converting to strings
When any value referenced by the URI template is null, a boolean or a
number, then it should first be converted into a string as follows:
null values SHOULD be replaced by the text "null"
boolean values SHOULD be replaced by their lower-case equivalents:
"true" or "false"
numbers SHOULD be replaced with their original JSON
representation.
In some software environments the original JSON representation of a
number will not be available (there is no way to tell the difference
between 1.0 and 1), so any reasonable representation should be used.
Schema and API authors should bear this in mind, and use other types
(such as string or boolean) if the exact representation is important.
5.1.1.3. Missing values
Sometimes, the appropriate values will not be available. For
example, the template might specify the use of object properties, but
the instance is an array or a string.
If any of the values required for the template are not present in the
JSON instance, then substitute values MAY be provided from another
source (such as default values). Otherwise, the link definition
SHOULD be considered not to apply to the instance.
5.2. rel
The value of the "rel" property indicates the name of the relation to
the target resource. The value MUST be a registered link relation
from the IANA Link Relation Type Registry established in RFC 5988
[RFC5988], or a normalized URI following the URI production of RFC
3986 [RFC3986].
The relation to the target is interpreted as from the instance that
the schema (or sub-schema) applies to, not any larger document that
the instance may have been found in.
Relationship definitions are not normally media type dependent, and
users are encouraged to utilize existing accepted relation
definitions.
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For example, if a schema is defined:
{
"links": [{
"rel": "self",
"href": "{id}"
}, {
"rel": "up",
"href": "{upId}"
}]
}
And if a collection of instance resources were retrieved with JSON
representation:
GET /Resource/
[{
"id": "thing",
"upId": "parent"
}, {
"id": "thing2",
"upId": "parent"
}]
This would indicate that for the first item in the collection, its
own (self) URI would resolve to "/Resource/thing" and the first
item's "up" relation SHOULD be resolved to the resource at
"/Resource/parent".
Note that these relationship values are case-insensitive, consistent
with their use in HTML and the HTTP Link header [RFC5988].
5.2.1. Security Considerations for "self" links
When link relation of "self" is used to denote a full representation
of an object, the user agent SHOULD NOT consider the representation
to be the authoritative representation of the resource denoted by the
target URI if the target URI is not equivalent to or a sub-path of
the the URI used to request the resource representation which
contains the target URI with the "self" link.
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For example, if a hyper schema was defined:
{
"links": [{
"rel": "self",
"href": "{id}"
}]
}
And a resource was requested from somesite.com:
GET /foo/
With a response of (with newlines and whitespace added):
Content-Type: application/json; profile="http://example.com/alpha"
[{
"id": "bar",
"name": "This representation can be safely treated
as authoritative "
}, {
"id": "/baz",
"name": "This representation should not be treated as
authoritative the user agent should make request the
resource from '/baz' to ensure it has the authoritative
representation"
}, {
"id": "http://othersite.com/something",
"name": "This representation
should also not be treated as authoritative and the
target resource representation should be retrieved
for the authoritative representation"
}]
5.3. title
This property defines a title for the link. The value must be a
string.
User agents MAY use this title when presenting the link to the user.
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5.4. targetSchema
This property provides a schema that is expected to describe the link
target, including what a client can expect if it makes an HTTP GET
request, and what it should send if it replaces the resource in an
HTTP PUT request. This property is advisory only.
5.4.1. Security Considerations for "targetSchema"
This property has similar security concerns to that of "mediaType".
Clients MUST NOT use the value of this property to aid in the
interpretation of the data received in response to following the
link, as this leaves "safe" data open to re-interpretation.
For example, suppose two programmers are having a discussion about
web security using a text-only message board. Here is some data from
that conversation, with a URI of:
http://forum.example.com/topics/152/comments/13
{
"topicId": 152,
"commentId": 13,
"from": {
"name": "Jane",
"id": 5
},
"to": {
"name": "Jason",
"id": 8
},
"message": "It's easy, just add some HTML like
this: <script>doSomethingEvil()</script>"
}
The message string was split over two lines for readability.
A third party might then write provide the following Link Description
Object at another location:
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{
"rel": "evil-attack",
"href": "http://forum.example.com/topics/152/comments/13",
"targetSchema": {
"properties": {
"message": {
"description": "Re-interpret `message` as HTML",
"media": {
"type": "text/html"
}
}
}
}
}
If the client used this "targetSchema" value when interpreting the
above data, then it might display the contents of "message" as HTML.
At this point, the JavaScript embedded in the message might be
executed (in the context of the "forum.example.com" domain).
5.5. mediaType
The value of this property is advisory only, and represents the media
type RFC 2046 [RFC2046], that is expected to be returned when
fetching this resource. This property value MAY be a media range
instead, using the same pattern defined in RFC 7231, section 5.3.1 -
HTTP "Accept" header [RFC7231].
This property is analogous to the "type" property of <a> elements in
HTML (advisory content type), or the "type" parameter in the HTTP
Link header [RFC5988]. User agents MAY use this information to
inform the interface they present to the user before the link is
followed, but this information MUST NOT use this information in the
interpretation of the resulting data. When deciding how to interpret
data obtained through following this link, the behaviour of user
agents MUST be identical regardless of the value of the this
property.
If this property's value is specified, and the link's target is to be
obtained using any protocol that supports the HTTP/1.1 "Accept"
header RFC 7231, section 5.3.1 [RFC7231], then user agents MAY use
the value of this property to aid in the assembly of that header when
making the request to the server.
If this property's value is not specified, then the value should be
taken to be "application/json".
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For example, if a schema is defined:
{
"links": [{
"rel": "self",
"href": "/{id}/json"
}, {
"rel": "alternate",
"href": "/{id}/html",
"mediaType": "text/html"
}, {
"rel": "alternate",
"href": "/{id}/rss",
"mediaType": "application/rss+xml"
}, {
"rel": "icon",
"href": "{id}/icon",
"mediaType": "image/*"
}]
}
A suitable instance described by this schema would have four links
defined. The link with a "rel" value of "self" would have an
expected MIME type of "application/json" (the default). The two
links with a "rel" value of "alternate" specify the locations of HTML
and RSS versions of the current item. The link with a "rel" value of
"icon" links to an image, but does not specify the exact format.
A visual user agent displaying the item from the above example might
present a button representing an RSS feed, which when pressed passes
the target URI (calculated "href" value) to an view more suited to
displaying it, such as a news feed aggregator tab.
Note that presenting the link in the above manner, or passing the URI
to a news feed aggregator view does not constitute interpretation of
the data, but an interpretation of the link. The interpretation of
the data itself is performed by the news feed aggregator, which
SHOULD reject any data that would not have also been interpreted as a
news feed, had it been displayed in the main view.
5.5.1. Security concerns for "mediaType"
The "mediaType" property in link definitions defines the expected
format of the link's target. However, this is advisory only, and
MUST NOT be considered authoritative.
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When choosing how to interpret data, the type information provided by
the server (or inferred from the filename, or any other usual method)
MUST be the only consideration, and the "mediaType" property of the
link MUST NOT be used. User agents MAY use this information to
determine how they represent the link or where to display it (for
example hover-text, opening in a new tab). If user agents decide to
pass the link to an external program, they SHOULD first verify that
the data is of a type that would normally be passed to that external
program.
This is to guard against re-interpretation of "safe" data, similar to
the precautions for "targetSchema".
5.6. Submission Form Properties
The following properties also apply to Link Description Objects, and
provide functionality analogous to HTMLforms [W3C.CR-html5-20140731],
by providing a means for making a request with client- or user-
selected information.
5.6.1. method
This property specifies that the client can construct a templated
query or non-idempotent request to a resource.
If "method" is "get", the link identifies how a user can compute the
URI of an arbritrary resource. For example, how compute a link to a
page of search results relating to the instance, for a user-selected
query term. Despite being named after GET, there is no constraint on
the method or protocol used to interact with the remote resource.
If "method" is "post", the link specifies how a user can construct a
document to submit to the link target for evaluation.
Values for this property SHOULD be lowercase, and SHOULD be compared
case-insensitive. Use of other values not defined here SHOULD be
ignored.
5.6.2. encType
If present, this property indicates the media type format the client
should use to encode a query parameter or send to the server. posting
to the collection of instances at the target resource. If the method
is "get", this will indicate how to encode the query-string that is
appended to the "href" link target. If the method is "post", this
indicates which media type to send to the server and how to encode
it.
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For example, with the following schema:
{
"links": [{
"encType": "application/x-www-form-urlencoded",
"method": "get",
"href": "/Product/",
"properties": {
"name": {
"description": "name of the product"
}
}
}]
}
This indicates that the client can query the server for instances
that have a specific name.
For example:
/Product/?name=Slinky
If the method is "post", "application/json" is the default media
type.
5.6.3. schema
This property contains a schema which defines the acceptable
structure of the document being encoded according to the "encType"
property.
Note that this does not provide data for any URI templates. This is
a separate concept from the "targetSchema" property, which is
describing the target information resource (including for replacing
the contents of the resource in a PUT request), unlike "schema" which
describes the user-submitted request data to be evaluated by the
resource.
6. References
6.1. Normative References
[RFC2045] Freed, N. and N. Borenstein, "Multipurpose Internet Mail
Extensions (MIME) Part One: Format of Internet Message
Bodies", RFC 2045, DOI 10.17487/RFC2045, November 1996,
<http://www.rfc-editor.org/info/rfc2045>.
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[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/
RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>.
[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
Resource Identifier (URI): Generic Syntax", STD 66, RFC
3986, DOI 10.17487/RFC3986, January 2005,
<http://www.rfc-editor.org/info/rfc3986>.
[RFC6570] Gregorio, J., Fielding, R., Hadley, M., Nottingham, M.,
and D. Orchard, "URI Template", RFC 6570, DOI 10.17487/
RFC6570, March 2012,
<http://www.rfc-editor.org/info/rfc6570>.
[json-schema]
Wright, A., "JSON Schema: A Media Type for Describing JSON
Documents", draft-wright-json-schema-00 (work in
progress), October 2016.
6.2. Informative References
[RFC2046] Freed, N. and N. Borenstein, "Multipurpose Internet Mail
Extensions (MIME) Part Two: Media Types", RFC 2046, DOI
10.17487/RFC2046, November 1996,
<http://www.rfc-editor.org/info/rfc2046>.
[RFC5988] Nottingham, M., "Web Linking", RFC 5988, DOI 10.17487/
RFC5988, October 2010,
<http://www.rfc-editor.org/info/rfc5988>.
[RFC7231] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
Protocol (HTTP/1.1): Semantics and Content", RFC 7231, DOI
10.17487/RFC7231, June 2014,
<http://www.rfc-editor.org/info/rfc7231>.
[W3C.CR-html5-20140731]
Berjon, R., Faulkner, S., Leithead, T., Navara, E.,
O'Connor, E., and S. Pfeiffer, "HTML5", World Wide
Web Consortium CR CR-html5-20140731, July 2014,
<http://www.w3.org/TR/2014/CR-html5-20140731>.
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Appendix A. Acknowledgments
Thanks to Gary Court, Francis Galiegue, Kris Zyp, and Geraint Luff
for their work on the initial drafts of JSON Schema.
Thanks to Jason Desrosiers, Daniel Perrett, Erik Wilde, Ben Hutton,
Evgeny Poberezkin, and Henry H. Andrews for their submissions and
patches to the document.
Appendix B. Change Log
[[CREF3: This section to be removed before leaving Internet-Draft
status.]]
draft-wright-json-schema-hyperschema-00
* "rel" is now optional
* rel="self" no longer changes URI base
* Added "base" keyword to change instance URI base
* Removed "root" link relation
* Removed "create" link relation
* Removed "full" link relation
* Removed "instances" link relation
* Removed special behavior for "describedBy" link relation
* Removed "pathStart" keyword
* Removed "fragmentResolution" keyword
* Updated references to JSON Pointer, HTML
* Changed behavior of "method" property to align with hypermedia
best current practices
draft-luff-json-hyper-schema-01
* Split from main specification.
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Authors' Addresses
Austin Wright (editor)
EMail: aaa@bzfx.net
Geraint Luff
Cambridge
UK
EMail: luffgd@gmail.com
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