Internet Engineering Task Force A. Wright, Ed.
Internet-Draft
Intended status: Informational G. Luff
Expires: October 17, 2017
H. Andrews, Ed.
Cloudflare, Inc.
April 15, 2017
JSON Schema Validation: A Vocabulary for Structural Validation of JSON
draft-wright-json-schema-validation-01
Abstract
JSON Schema (application/schema+json) has several purposes, one of
which is JSON instance validation. This document specifies a
vocabulary for JSON Schema to describe the meaning of JSON documents,
provide hints for user interfaces working with JSON data, and to make
assertions about what a valid document must look like.
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
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 October 17, 2017.
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Copyright Notice
Copyright (c) 2017 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
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the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions and Terminology . . . . . . . . . . . . . . . . . 4
3. Interoperability considerations . . . . . . . . . . . . . . . 4
3.1. Validation of string instances . . . . . . . . . . . . . 4
3.2. Validation of numeric instances . . . . . . . . . . . . . 4
3.3. Regular expressions . . . . . . . . . . . . . . . . . . . 4
4. General validation considerations . . . . . . . . . . . . . . 5
4.1. Keywords and instance primitive types . . . . . . . . . . 5
4.2. Validation of primitive types and child values . . . . . 5
4.3. Constraints and missing keywords . . . . . . . . . . . . 6
4.4. Keyword independence . . . . . . . . . . . . . . . . . . 6
5. Meta-schema . . . . . . . . . . . . . . . . . . . . . . . . . 6
6. Validation keywords . . . . . . . . . . . . . . . . . . . . . 6
6.1. multipleOf . . . . . . . . . . . . . . . . . . . . . . . 6
6.2. maximum . . . . . . . . . . . . . . . . . . . . . . . . . 6
6.3. exclusiveMaximum . . . . . . . . . . . . . . . . . . . . 7
6.4. minimum . . . . . . . . . . . . . . . . . . . . . . . . . 7
6.5. exclusiveMinimum . . . . . . . . . . . . . . . . . . . . 7
6.6. maxLength . . . . . . . . . . . . . . . . . . . . . . . . 7
6.7. minLength . . . . . . . . . . . . . . . . . . . . . . . . 7
6.8. pattern . . . . . . . . . . . . . . . . . . . . . . . . . 8
6.9. items . . . . . . . . . . . . . . . . . . . . . . . . . . 8
6.10. additionalItems . . . . . . . . . . . . . . . . . . . . . 8
6.11. maxItems . . . . . . . . . . . . . . . . . . . . . . . . 9
6.12. minItems . . . . . . . . . . . . . . . . . . . . . . . . 9
6.13. uniqueItems . . . . . . . . . . . . . . . . . . . . . . . 9
6.14. contains . . . . . . . . . . . . . . . . . . . . . . . . 9
6.15. maxProperties . . . . . . . . . . . . . . . . . . . . . . 9
6.16. minProperties . . . . . . . . . . . . . . . . . . . . . . 9
6.17. required . . . . . . . . . . . . . . . . . . . . . . . . 10
6.18. properties . . . . . . . . . . . . . . . . . . . . . . . 10
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6.19. patternProperties . . . . . . . . . . . . . . . . . . . . 10
6.20. additionalProperties . . . . . . . . . . . . . . . . . . 11
6.21. dependencies . . . . . . . . . . . . . . . . . . . . . . 11
6.22. propertyNames . . . . . . . . . . . . . . . . . . . . . . 11
6.23. enum . . . . . . . . . . . . . . . . . . . . . . . . . . 12
6.24. const . . . . . . . . . . . . . . . . . . . . . . . . . . 12
6.25. type . . . . . . . . . . . . . . . . . . . . . . . . . . 12
6.26. allOf . . . . . . . . . . . . . . . . . . . . . . . . . . 12
6.27. anyOf . . . . . . . . . . . . . . . . . . . . . . . . . . 12
6.28. oneOf . . . . . . . . . . . . . . . . . . . . . . . . . . 13
6.29. not . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
7. Metadata keywords . . . . . . . . . . . . . . . . . . . . . . 13
7.1. definitions . . . . . . . . . . . . . . . . . . . . . . . 13
7.2. "title" and "description" . . . . . . . . . . . . . . . . 14
7.3. "default" . . . . . . . . . . . . . . . . . . . . . . . . 14
7.4. "examples" . . . . . . . . . . . . . . . . . . . . . . . 14
8. Semantic validation with "format" . . . . . . . . . . . . . . 14
8.1. Foreword . . . . . . . . . . . . . . . . . . . . . . . . 14
8.2. Implementation requirements . . . . . . . . . . . . . . . 15
8.3. Defined formats . . . . . . . . . . . . . . . . . . . . . 15
8.3.1. date-time . . . . . . . . . . . . . . . . . . . . . . 15
8.3.2. email . . . . . . . . . . . . . . . . . . . . . . . . 15
8.3.3. hostname . . . . . . . . . . . . . . . . . . . . . . 15
8.3.4. ipv4 . . . . . . . . . . . . . . . . . . . . . . . . 15
8.3.5. ipv6 . . . . . . . . . . . . . . . . . . . . . . . . 16
8.3.6. uri . . . . . . . . . . . . . . . . . . . . . . . . . 16
8.3.7. uri-reference . . . . . . . . . . . . . . . . . . . . 16
8.3.8. uri-template . . . . . . . . . . . . . . . . . . . . 16
8.3.9. json-pointer . . . . . . . . . . . . . . . . . . . . 16
9. Security considerations . . . . . . . . . . . . . . . . . . . 16
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 17
10.1. Normative References . . . . . . . . . . . . . . . . . . 17
10.2. Informative References . . . . . . . . . . . . . . . . . 17
Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 19
Appendix B. ChangeLog . . . . . . . . . . . . . . . . . . . . . 19
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 20
1. Introduction
JSON Schema can be used to require that a given JSON document (an
instance) satisfies a certain number of criteria. These criteria are
asserted by using keywords described in this specification. In
addition, a set of keywords is also defined to assist in interactive
user interface instance generation.
This specification will use the terminology defined by the JSON
Schema core [json-schema] specification.
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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].
This specification uses the term "container instance" to refer to
both array and object instances. It uses the term "children
instances" to refer to array elements or object member values.
Elements in an array value are said to be unique if no two elements
of this array are equal [json-schema].
3. Interoperability considerations
3.1. Validation of string instances
It should be noted that the nul character (\u0000) is valid in a JSON
string. An instance to validate may contain a string value with this
character, regardless of the ability of the underlying programming
language to deal with such data.
3.2. Validation of numeric instances
The JSON specification allows numbers with arbitrary precision, and
JSON Schema does not add any such bounds. This means that numeric
instances processed by JSON Schema can be arbitrarily large and/or
have an arbitrarily long decimal part, regardless of the ability of
the underlying programming language to deal with such data.
3.3. Regular expressions
Two validation keywords, "pattern" and "patternProperties", use
regular expressions to express constraints. These regular
expressions SHOULD be valid according to the ECMA 262 [ecma262]
regular expression dialect.
Furthermore, given the high disparity in regular expression
constructs support, schema authors SHOULD limit themselves to the
following regular expression tokens:
individual Unicode characters, as defined by the JSON
specification [RFC7159];
simple character classes ([abc]), range character classes ([a-z]);
complemented character classes ([^abc], [^a-z]);
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simple quantifiers: "+" (one or more), "*" (zero or more), "?"
(zero or one), and their lazy versions ("+?", "*?", "??");
range quantifiers: "{x}" (exactly x occurrences), "{x,y}" (at
least x, at most y, occurrences), {x,} (x occurrences or more),
and their lazy versions;
the beginning-of-input ("^") and end-of-input ("$") anchors;
simple grouping ("(...)") and alternation ("|").
Finally, implementations MUST NOT take regular expressions to be
anchored, neither at the beginning nor at the end. This means, for
instance, the pattern "es" matches "expression".
4. General validation considerations
4.1. Keywords and instance primitive types
Most validation keywords only constrain values within a certain
primitive type. When the type of the instance is not of the type
targeted by the keyword, the validation succeeds.
For example, the "maxLength" keyword will only restrict certain
strings (that are too long) from being valid. If the instance is a
number, boolean, null, array, or object, the keyword passes
validation.
4.2. Validation of primitive types and child values
Two of the primitive types, array and object, allow for child values.
The validation of the primitive type is considered separately from
the validation of child instances.
For arrays, primitive type validation consists of validating
restrictions on length with "minItems" and "maxItems", while "items"
and "additionalItems" determine which subschemas apply to which
elements of the array. In addition, "uniqueItems" and "contains"
validate array contents as a whole.
For objects, primitive type validation consists of validating
restrictions on which and how many properties appear with "required",
"minProperties", "maxProperties", "propertyNames", and the string
array form of "dependencies", while "properties",
"patternProperties", and "additionalProperties" determine which
subschemas apply to which object property values. In addition, the
schema form of "dependencies" validates the object as a whole based
on the presence of specific property names.
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4.3. Constraints and missing keywords
Each JSON Schema validation keyword adds constraints that an instance
must satisfy in order to successfully validate.
Validation keywords that are missing never restrict validation. In
some cases, this no-op behavior is identical to a keyword that exists
with certain values, and these values are noted where known.
4.4. Keyword independence
Validation keywords typically operate independently, without
affecting each other's outcomes.
For schema author convenience, there are some exceptions:
"additionalProperties", whose behavior is defined in terms of
"properties" and "patternProperties"; and
"additionalItems", whose behavior is defined in terms of "items".
5. Meta-schema
The current URI for the JSON Schema Validation is <http://json-
schema.org/draft-06/schema#>.
6. Validation keywords
Validation keywords in a schema impose requirements for successful
validation of an instance.
6.1. multipleOf
The value of "multipleOf" MUST be a number, strictly greater than 0.
A numeric instance is valid only if division by this keyword's value
results in an integer.
6.2. maximum
The value of "maximum" MUST be a number, representing an inclusive
upper limit for a numeric instance.
If the instance is a number, then this keyword validates only if the
instance is less than or exactly equal to "maximum".
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6.3. exclusiveMaximum
The value of "exclusiveMaximum" MUST be number, representing an
exclusive upper limit for a numeric instance.
If the instance is a number, then the instance is valid only if it
has a value strictly less than (not equal to) "exclusiveMaximum".
6.4. minimum
The value of "minimum" MUST be a number, representing an inclusive
upper limit for a numeric instance.
If the instance is a number, then this keyword validates only if the
instance is greater than or exactly equal to "minimum".
6.5. exclusiveMinimum
The value of "exclusiveMinimum" MUST be number, representing an
exclusive upper limit for a numeric instance.
If the instance is a number, then the instance is valid only if it
has a value strictly greater than (not equal to) "exclusiveMinimum".
6.6. maxLength
The value of this keyword MUST be a non-negative integer.
A string instance is valid against this keyword if its length is less
than, or equal to, the value of this keyword.
The length of a string instance is defined as the number of its
characters as defined by RFC 7159 [RFC7159].
6.7. minLength
The value of this keyword MUST be a non-negative integer.
A string instance is valid against this keyword if its length is
greater than, or equal to, the value of this keyword.
The length of a string instance is defined as the number of its
characters as defined by RFC 7159 [RFC7159].
Omitting this keyword has the same behavior as a value of 0.
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6.8. pattern
The value of this keyword MUST be a string. This string SHOULD be a
valid regular expression, according to the ECMA 262 regular
expression dialect.
A string instance is considered valid if the regular expression
matches the instance successfully. Recall: regular expressions are
not implicitly anchored.
6.9. items
The value of "items" MUST be either a valid JSON Schema or an array
of valid JSON Schemas.
This keyword determines how child instances validate for arrays, and
does not directly validate the immediate instance itself.
If "items" is a schema, validation succeeds if all elements in the
array successfully validate against that schema.
If "items" is an array of schemas, validation succeeds if each
element of the instance validates against the schema at the same
position, if any.
Omitting this keyword has the same behavior as an empty schema.
6.10. additionalItems
The value of "additionalItems" MUST be a valid JSON Schema.
This keyword determines how child instances validate for arrays, and
does not directly validate the immediate instance itself.
If "items" is an array of schemas, validation succeeds if every
instance element at a position greater than the size of "items"
validates against "additionalItems".
Otherwise, "additionalItems" MUST be ignored, as the "items" schema
(possibly the default value of an empty schema) is applied to all
elements.
Omitting this keyword has the same behavior as an empty schema.
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6.11. maxItems
The value of this keyword MUST be a non-negative integer.
An array instance is valid against "maxItems" if its size is less
than, or equal to, the value of this keyword.
6.12. minItems
The value of this keyword MUST be a non-negative integer.
An array instance is valid against "minItems" if its size is greater
than, or equal to, the value of this keyword.
Omitting this keyword has the same behavior as a value of 0.
6.13. uniqueItems
The value of this keyword MUST be a boolean.
If this keyword has boolean value false, the instance validates
successfully. If it has boolean value true, the instance validates
successfully if all of its elements are unique.
Omitting this keyword has the same behavior as a value of false.
6.14. contains
The value of this keyword MUST be a valid JSON Schema.
An array instance is valid against "contains" if at least one of its
elements is valid against the given schema.
6.15. maxProperties
The value of this keyword MUST be a non-negative integer.
An object instance is valid against "maxProperties" if its number of
properties is less than, or equal to, the value of this keyword.
6.16. minProperties
The value of this keyword MUST be a non-negative integer.
An object instance is valid against "minProperties" if its number of
properties is greater than, or equal to, the value of this keyword.
Omitting this keyword has the same behavior as a value of 0.
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6.17. required
The value of this keyword MUST be an array. Elements of this array,
if any, MUST be strings, and MUST be unique.
An object instance is valid against this keyword if every item in the
array is the name of a property in the instance.
Omitting this keyword has the same behavior as an empty array.
6.18. properties
The value of "properties" MUST be an object. Each value of this
object MUST be a valid JSON Schema.
This keyword determines how child instances validate for objects, and
does not directly validate the immediate instance itself.
Validation succeeds if, for each name that appears in both the
instance and as a name within this keyword's value, the child
instance for that name successfully validates against the
corresponding schema.
Omitting this keyword has the same behavior as an empty object.
6.19. patternProperties
The value of "patternProperties" MUST be an object. Each property
name of this object SHOULD be a valid regular expression, according
to the ECMA 262 regular expression dialect. Each property value of
this object MUST be a valid JSON Schema.
This keyword determines how child instances validate for objects, and
does not directly validate the immediate instance itself. Validation
of the primitive instance type against this keyword always succeeds.
Validation succeeds if, for each instance name that matches any
regular expressions that appear as a property name in this keyword's
value, the child instance for that name successfully validates
against each schema that corresponds to a matching regular
expression.
Omitting this keyword has the same behavior as an empty object.
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6.20. additionalProperties
The value of "additionalProperties" MUST be a valid JSON Schema.
This keyword determines how child instances validate for objects, and
does not directly validate the immediate instance itself.
Validation with "additionalProperties" applies only to the child
values of instance names that do not match any names in "properties",
and do not match any regular expression in "patternProperties".
For all such properties, validation succeeds if the child instance
validates against the "additionalProperties" schema.
Omitting this keyword has the same behavior as an empty schema.
6.21. dependencies
This keyword specifies rules that are evaluated if the instance is an
object and contains a certain property.
This keyword's value MUST be an object. Each property specifies a
dependency. Each dependency value MUST be an array or a valid JSON
Schema.
If the dependency value is a subschema, and the dependency key is a
property in the instance, the entire instance must validate against
the dependency value.
If the dependency value is an array, each element in the array, if
any, MUST be a string, and MUST be unique. If the dependency key is
a property in the instance, each of the items in the dependency value
must be a property that exists in the instance.
Omitting this keyword has the same behavior as an empty object.
6.22. propertyNames
The value of "propertyNames" MUST be a valid JSON Schema.
If the instance is an object, this keyword validates if every
property name in the instance validates against the provided schema.
Note the property name that the schema is testing will always be a
string.
Omitting this keyword has the same behavior as an empty schema.
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6.23. enum
The value of this keyword MUST be an array. This array SHOULD have
at least one element. Elements in the array SHOULD be unique.
An instance validates successfully against this keyword if its value
is equal to one of the elements in this keyword's array value.
Elements in the array might be of any value, including null.
6.24. const
The value of this keyword MAY be of any type, including null.
An instance validates successfully against this keyword if its value
is equal to the value of the keyword.
6.25. type
The value of this keyword MUST be either a string or an array. If it
is an array, elements of the array MUST be strings and MUST be
unique.
String values MUST be one of the six primitive types ("null",
"boolean", "object", "array", "number", or "string"), or "integer"
which matches any number with a zero fractional part.
An instance validates if and only if the instance is in any of the
sets listed for this keyword.
6.26. allOf
This keyword's value MUST be a non-empty array. Each item of the
array MUST be a valid JSON Schema.
An instance validates successfully against this keyword if it
validates successfully against all schemas defined by this keyword's
value.
6.27. anyOf
This keyword's value MUST be a non-empty array. Each item of the
array MUST be a valid JSON Schema.
An instance validates successfully against this keyword if it
validates successfully against at least one schema defined by this
keyword's value.
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6.28. oneOf
This keyword's value MUST be a non-empty array. Each item of the
array MUST be a valid JSON Schema.
An instance validates successfully against this keyword if it
validates successfully against exactly one schema defined by this
keyword's value.
6.29. not
This keyword's value MUST be a valid JSON Schema.
An instance is valid against this keyword if it fails to validate
successfully against the schema defined by this keyword.
7. Metadata keywords
7.1. definitions
This keyword's value MUST be an object. Each member value of this
object MUST be a valid JSON Schema.
This keyword plays no role in validation per se. Its role is to
provide a standardized location for schema authors to inline JSON
Schemas into a more general schema.
As an example, here is a schema describing an array of positive
integers, where the positive integer constraint is a subschema in
"definitions":
{
"type": "array",
"items": { "$ref": "#/definitions/positiveInteger" },
"definitions": {
"positiveInteger": {
"type": "integer",
"exclusiveMinimum": 0
}
}
}
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7.2. "title" and "description"
The value of both of these keywords MUST be a string.
Both of these keywords can be used to decorate a user interface with
information about the data produced by this user interface. A title
will preferably be short, whereas a description will provide
explanation about the purpose of the instance described by this
schema.
7.3. "default"
There are no restrictions placed on the value of this keyword.
This keyword can be used to supply a default JSON value associated
with a particular schema. It is RECOMMENDED that a default value be
valid against the associated schema.
7.4. "examples"
The value of this keyword MUST be an array. There are no
restrictions placed on the values within the array.
This keyword can be used to provide sample JSON values associated
with a particular schema, for the purpose of illustrating usage. It
is RECOMMENDED that these values be valid against the associated
schema.
Implementations MAY use the value of "default", if present, as an
additional example. If "examples" is absent, "default" MAY still be
used in this manner.
8. Semantic validation with "format"
8.1. Foreword
Structural validation alone may be insufficient to validate that an
instance meets all the requirements of an application. The "format"
keyword is defined to allow interoperable semantic validation for a
fixed subset of values which are accurately described by
authoritative resources, be they RFCs or other external
specifications.
The value of this keyword is called a format attribute. It MUST be a
string. A format attribute can generally only validate a given set
of instance types. If the type of the instance to validate is not in
this set, validation for this format attribute and instance SHOULD
succeed.
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8.2. Implementation requirements
Implementations MAY support the "format" keyword. Should they choose
to do so:
they SHOULD implement validation for attributes defined below;
they SHOULD offer an option to disable validation for this
keyword.
Implementations MAY add custom format attributes. Save for agreement
between parties, schema authors SHALL NOT expect a peer
implementation to support this keyword and/or custom format
attributes.
8.3. Defined formats
8.3.1. date-time
This attribute applies to string instances.
A string instance is valid against this attribute if it is a valid
date representation as defined by RFC 3339, section 5.6 [RFC3339].
8.3.2. email
This attribute applies to string instances.
A string instance is valid against this attribute if it is a valid
Internet email address as defined by RFC 5322, section 3.4.1
[RFC5322].
8.3.3. hostname
This attribute applies to string instances.
A string instance is valid against this attribute if it is a valid
representation for an Internet host name, as defined by RFC 1034,
section 3.1 [RFC1034].
8.3.4. ipv4
This attribute applies to string instances.
A string instance is valid against this attribute if it is a valid
representation of an IPv4 address according to the "dotted-quad" ABNF
syntax as defined in RFC 2673, section 3.2 [RFC2673].
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8.3.5. ipv6
This attribute applies to string instances.
A string instance is valid against this attribute if it is a valid
representation of an IPv6 address as defined in RFC 2373, section 2.2
[RFC2373].
8.3.6. uri
This attribute applies to string instances.
A string instance is valid against this attribute if it is a valid
URI, according to [RFC3986].
8.3.7. uri-reference
This attribute applies to string instances.
A string instance is valid against this attribute if it is a valid
URI Reference (either a URI or a relative-reference), according to
[RFC3986].
8.3.8. uri-template
This attribute applies to string instances.
A string instance is valid against this attribute if it is a valid
URI Template (of any level), according to [RFC6570].
8.3.9. json-pointer
This attribute applies to string instances.
A string instance is valid against this attribute if it is a valid
JSON Pointer, according to [RFC6901]
9. Security considerations
JSON Schema validation defines a vocabulary for JSON Schema core and
concerns all the security considerations listed there.
JSON Schema validation allows the use of Regular Expressions, which
have numerous different (often incompatible) implementations. Some
implementations allow the embedding of arbitrary code, which is
outside the scope of JSON Schema and MUST NOT be permitted. Regular
expressions can often also be crafted to be extremely expensive to
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compute (with so-called "catastrophic backtracking"), resulting in a
denial-of-service attack.
10. References
10.1. Normative References
[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>.
[json-schema]
"JSON Schema: A Media Type for Describing JSON Documents",
draft-wright-json-schema-00 (work in progress), October
2016.
10.2. Informative References
[RFC1034] Mockapetris, P., "Domain names - concepts and facilities",
STD 13, RFC 1034, DOI 10.17487/RFC1034, November 1987,
<http://www.rfc-editor.org/info/rfc1034>.
[RFC2373] Hinden, R. and S. Deering, "IP Version 6 Addressing
Architecture", RFC 2373, DOI 10.17487/RFC2373, July 1998,
<http://www.rfc-editor.org/info/rfc2373>.
[RFC2673] Crawford, M., "Binary Labels in the Domain Name System",
RFC 2673, DOI 10.17487/RFC2673, August 1999,
<http://www.rfc-editor.org/info/rfc2673>.
[RFC3339] Klyne, G. and C. Newman, "Date and Time on the Internet:
Timestamps", RFC 3339, DOI 10.17487/RFC3339, July 2002,
<http://www.rfc-editor.org/info/rfc3339>.
[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>.
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[RFC6901] Bryan, P., Ed., Zyp, K., and M. Nottingham, Ed.,
"JavaScript Object Notation (JSON) Pointer", RFC 6901,
DOI 10.17487/RFC6901, April 2013,
<http://www.rfc-editor.org/info/rfc6901>.
[RFC7159] Bray, T., Ed., "The JavaScript Object Notation (JSON) Data
Interchange Format", RFC 7159, DOI 10.17487/RFC7159, March
2014, <http://www.rfc-editor.org/info/rfc7159>.
[RFC5322] Resnick, P., Ed., "Internet Message Format", RFC 5322,
DOI 10.17487/RFC5322, October 2008,
<http://www.rfc-editor.org/info/rfc5322>.
[ecma262] "ECMA 262 specification", <http://www.ecma-
international.org/publications/files/ECMA-ST/
Ecma-262.pdf>.
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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, Brad Bowman, Gowry Sankar, Donald Pipowitch, and
Dave Finlay for their submissions and patches to the document.
Appendix B. ChangeLog
[[CREF1: This section to be removed before leaving Internet-Draft
status.]]
draft-wright-json-schema-validation-01
* Standardized on hyphenated format names ("uriref" becomes "uri-
ref")
* Add the formats "uri-template" and "json-pointer"
* Changed "exclusiveMaximum"/"exclusiveMinimum" from boolean
modifiers of "maximum"/"minimum" to independent numeric fields.
* Split the additionalItems/items into two sections
* Reworked properties/patternProperties/additionalProperties
definition
* Added "examples" keyword
* Added "contains" keyword
* Allow empty "required" and "dependencies" arrays
* Fixed "type" reference to primitive types
* Added "const" keyword
* Added "propertyNames" keyword
draft-wright-json-schema-validation-00
* Added additional security considerations
* Removed reference to "latest version" meta-schema, use numbered
version instead
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* Rephrased many keyword definitions for brevity
* Added "uriref" format that also allows relative URI references
draft-fge-json-schema-validation-01
* Initial draft.
* Salvaged from draft v3.
* Redefine the "required" keyword.
* Remove "extends", "disallow"
* Add "anyOf", "allOf", "oneOf", "not", "definitions",
"minProperties", "maxProperties".
* "dependencies" member values can no longer be single strings;
at least one element is required in a property dependency
array.
* Rename "divisibleBy" to "multipleOf".
* "type" arrays can no longer have schemas; remove "any" as a
possible value.
* Rework the "format" section; make support optional.
* "format": remove attributes "phone", "style", "color"; rename
"ip-address" to "ipv4"; add references for all attributes.
* Provide algorithms to calculate schema(s) for array/object
instances.
* Add interoperability considerations.
Authors' Addresses
Austin Wright (editor)
EMail: aaa@bzfx.net
Geraint Luff
EMail: luffgd@gmail.com
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Henry Andrews (editor)
Cloudflare, Inc.
EMail: henry@cloudflare.com
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