=============================================================================================================================================================== Network Working Group D. Crockford | Internet Engineering Task Force (IETF) T. Bray, Ed. Request for Comments: 4627 JSON.org | Request for Comments: 7159 Google, Inc. Category: Informational July 2006 | Obsoletes: 4627, 7158 March 2014 > Category: Standards Track > ISSN: 2070-1721 The application/json Media Type for JavaScript Object Notation (JSON) | The JavaScript Object Notation (JSON) Data Interchange Format < Status of This Memo < < This memo provides information for the Internet community. It does < not specify an Internet standard of any kind. Distribution of this < memo is unlimited. < < Copyright Notice < < Copyright (C) The Internet Society (2006). < Abstract Abstract JavaScript Object Notation (JSON) is a lightweight, text-based, JavaScript Object Notation (JSON) is a lightweight, text-based, language-independent data interchange format. It was derived from language-independent data interchange format. It was derived from the ECMAScript Programming Language Standard. JSON defines a small the ECMAScript Programming Language Standard. JSON defines a small set of formatting rules for the portable representation of structured set of formatting rules for the portable representation of structured data. data. > This document removes inconsistencies with other specifications of > JSON, repairs specification errors, and offers experience-based > interoperability guidance. > > Status of This Memo > > This is an Internet Standards Track document. > > This document is a product of the Internet Engineering Task Force > (IETF). It represents the consensus of the IETF community. It has > received public review and has been approved for publication by the > Internet Engineering Steering Group (IESG). Further information on > Internet Standards is available in Section 2 of RFC 5741. > > Information about the current status of this document, any errata, > and how to provide feedback on it may be obtained at > http://www.rfc-editor.org/info/rfc7159. > > > > > > > > > > > > > > > > > > Bray Standards Track [Page 1] > > RFC 7159 JSON March 2014 > > > Copyright Notice > > Copyright (c) 2014 IETF Trust and the persons identified as the > document authors. All rights reserved. > > This document is subject to BCP 78 and the IETF Trust's Legal > Provisions Relating to IETF Documents > (http://trustee.ietf.org/license-info) in effect on the date of > publication of this document. Please review these documents > carefully, as they describe your rights and restrictions with respect > to this document. Code Components extracted from this document must > include Simplified BSD License text as described in Section 4.e of > the Trust Legal Provisions and are provided without warranty as > described in the Simplified BSD License. > > This document may contain material from IETF Documents or IETF > Contributions published or made publicly available before November > 10, 2008. The person(s) controlling the copyright in some of this > material may not have granted the IETF Trust the right to allow > modifications of such material outside the IETF Standards Process. > Without obtaining an adequate license from the person(s) controlling > the copyright in such materials, this document may not be modified > outside the IETF Standards Process, and derivative works of it may > not be created outside the IETF Standards Process, except to format > it for publication as an RFC or to translate it into languages other > than English. > > > > > > > > > > > > > > > > > > > > > > > > > > Bray Standards Track [Page 2] > > RFC 7159 JSON March 2014 > > > Table of Contents > > 1. Introduction ....................................................3 > 1.1. Conventions Used in This Document ..........................4 > 1.2. Specifications of JSON .....................................4 > 1.3. Introduction to This Revision ..............................4 > 2. JSON Grammar ....................................................4 > 3. Values ..........................................................5 > 4. Objects .........................................................6 > 5. Arrays ..........................................................6 > 6. Numbers .........................................................6 > 7. Strings .........................................................8 > 8. String and Character Issues .....................................9 > 8.1. Character Encoding .........................................9 > 8.2. Unicode Characters .........................................9 > 8.3. String Comparison ..........................................9 > 9. Parsers ........................................................10 > 10. Generators ....................................................10 > 11. IANA Considerations ...........................................10 > 12. Security Considerations .......................................11 > 13. Examples ......................................................12 > 14. Contributors ..................................................13 > 15. References ....................................................13 > 15.1. Normative References .....................................13 > 15.2. Informative References ...................................13 > Appendix A. Changes from RFC 4627 .................................15 > =============================================================================================================================================================== 1. Introduction 1. Introduction JavaScript Object Notation (JSON) is a text format for the JavaScript Object Notation (JSON) is a text format for the serialization of structured data. It is derived from the object serialization of structured data. It is derived from the object literals of JavaScript, as defined in the ECMAScript Programming literals of JavaScript, as defined in the ECMAScript Programming Language Standard, Third Edition [ECMA]. | Language Standard, Third Edition [ECMA-262]. JSON can represent four primitive types (strings, numbers, booleans, JSON can represent four primitive types (strings, numbers, booleans, and null) and two structured types (objects and arrays). and null) and two structured types (objects and arrays). A string is a sequence of zero or more Unicode characters [UNICODE]. A string is a sequence of zero or more Unicode characters [UNICODE]. > Note that this citation references the latest version of Unicode > rather than a specific release. It is not expected that future > changes in the UNICODE specification will impact the syntax of JSON. An object is an unordered collection of zero or more name/value An object is an unordered collection of zero or more name/value pairs, where a name is a string and a value is a string, number, pairs, where a name is a string and a value is a string, number, boolean, null, object, or array. boolean, null, object, or array. An array is an ordered sequence of zero or more values. An array is an ordered sequence of zero or more values. The terms "object" and "array" come from the conventions of < JavaScript. < < JSON's design goals were for it to be minimal, portable, textual, and < a subset of JavaScript. < Crockford Informational [Page 1] | Bray Standards Track [Page 3] RFC 4627 JSON July 2006 | RFC 7159 JSON March 2014 > The terms "object" and "array" come from the conventions of > JavaScript. > > JSON's design goals were for it to be minimal, portable, textual, and > a subset of JavaScript. > 1.1. Conventions Used in This Document 1.1. Conventions Used in This Document The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119]. document are to be interpreted as described in [RFC2119]. The grammatical rules in this document are to be interpreted as The grammatical rules in this document are to be interpreted as described in [RFC4234]. | described in [RFC5234]. > > 1.2. Specifications of JSON > > This document updates [RFC4627], which describes JSON and registers > the media type "application/json". > > A description of JSON in ECMAScript terms appears in Version 5.1 of > the ECMAScript specification [ECMA-262], Section 15.12. JSON is also > described in [ECMA-404]. > > All of the specifications of JSON syntax agree on the syntactic > elements of the language. > > 1.3. Introduction to This Revision > > In the years since the publication of RFC 4627, JSON has found very > wide use. This experience has revealed certain patterns, which, > while allowed by its specifications, have caused interoperability > problems. > > Also, a small number of errata have been reported (see RFC Errata IDs > 607 [Err607] and 3607 [Err3607]). > > This document's goal is to apply the errata, remove inconsistencies > with other specifications of JSON, and highlight practices that can > lead to interoperability problems. =============================================================================================================================================================== 2. JSON Grammar 2. JSON Grammar A JSON text is a sequence of tokens. The set of tokens includes six A JSON text is a sequence of tokens. The set of tokens includes six structural characters, strings, numbers, and three literal names. structural characters, strings, numbers, and three literal names. A JSON text is a serialized object or array. | A JSON text is a serialized value. Note that certain previous > specifications of JSON constrained a JSON text to be an object or an JSON-text = object / array | > > Bray Standards Track [Page 4] > > RFC 7159 JSON March 2014 > > > array. Implementations that generate only objects or arrays where a > JSON text is called for will be interoperable in the sense that all > implementations will accept these as conforming JSON texts. > > JSON-text = ws value ws These are the six structural characters: These are the six structural characters: begin-array = ws %x5B ws ; [ left square bracket begin-array = ws %x5B ws ; [ left square bracket begin-object = ws %x7B ws ; { left curly bracket begin-object = ws %x7B ws ; { left curly bracket end-array = ws %x5D ws ; ] right square bracket end-array = ws %x5D ws ; ] right square bracket end-object = ws %x7D ws ; } right curly bracket end-object = ws %x7D ws ; } right curly bracket name-separator = ws %x3A ws ; : colon name-separator = ws %x3A ws ; : colon value-separator = ws %x2C ws ; , comma value-separator = ws %x2C ws ; , comma Insignificant whitespace is allowed before or after any of the six Insignificant whitespace is allowed before or after any of the six structural characters. structural characters. ws = *( ws = *( %x20 / ; Space | %x20 / ; Space %x09 / ; Horizontal tab | %x09 / ; Horizontal tab %x0A / ; Line feed or New line | %x0A / ; Line feed or New line %x0D ; Carriage return | %x0D ) ; Carriage return ) < =============================================================================================================================================================== 2.1. Values | 3. Values A JSON value MUST be an object, array, number, or string, or one of A JSON value MUST be an object, array, number, or string, or one of the following three literal names: the following three literal names: false null true false null true > The literal names MUST be lowercase. No other literal names are > allowed. > value = false / null / true / object / array / number / string Crockford Informational [Page 2] | false = %x66.61.6c.73.65 ; false < RFC 4627 JSON July 2006 < > null = %x6e.75.6c.6c ; null > > true = %x74.72.75.65 ; true The literal names MUST be lowercase. No other literal names are < allowed. < value = false / null / true / object / array / number / string < false = %x66.61.6c.73.65 ; false < null = %x6e.75.6c.6c ; null < true = %x74.72.75.65 ; true | Bray Standards Track [Page 5] > > RFC 7159 JSON March 2014 > =============================================================================================================================================================== 2.2. Objects | 4. Objects An object structure is represented as a pair of curly brackets An object structure is represented as a pair of curly brackets surrounding zero or more name/value pairs (or members). A name is a surrounding zero or more name/value pairs (or members). A name is a string. A single colon comes after each name, separating the name string. A single colon comes after each name, separating the name from the value. A single comma separates a value from a following from the value. A single comma separates a value from a following name. The names within an object SHOULD be unique. name. The names within an object SHOULD be unique. object = begin-object [ member *( value-separator member ) ] object = begin-object [ member *( value-separator member ) ] end-object | end-object member = string name-separator value member = string name-separator value > An object whose names are all unique is interoperable in the sense > that all software implementations receiving that object will agree on > the name-value mappings. When the names within an object are not > unique, the behavior of software that receives such an object is > unpredictable. Many implementations report the last name/value pair > only. Other implementations report an error or fail to parse the > object, and some implementations report all of the name/value pairs, > including duplicates. > > JSON parsing libraries have been observed to differ as to whether or > not they make the ordering of object members visible to calling > software. Implementations whose behavior does not depend on member > ordering will be interoperable in the sense that they will not be > affected by these differences. > =============================================================================================================================================================== 2.3. Arrays | 5. Arrays An array structure is represented as square brackets surrounding zero An array structure is represented as square brackets surrounding zero or more values (or elements). Elements are separated by commas. or more values (or elements). Elements are separated by commas. array = begin-array [ value *( value-separator value ) ] end-array | array = begin-array [ value *( value-separator value ) ] end-array > > There is no requirement that the values in an array be of the same > type. =============================================================================================================================================================== 2.4. Numbers | 6. Numbers The representation of numbers is similar to that used in most The representation of numbers is similar to that used in most programming languages. A number contains an integer component that | programming languages. A number is represented in base 10 using may be prefixed with an optional minus sign, which may be followed by | decimal digits. It contains an integer component that may be a fraction part and/or an exponent part. | prefixed with an optional minus sign, which may be followed by a | fraction part and/or an exponent part. Leading zeros are not Octal and hex forms are not allowed. Leading zeros are not allowed. | allowed. A fraction part is a decimal point followed by one or more digits. A fraction part is a decimal point followed by one or more digits. An exponent part begins with the letter E in upper or lowercase, | > > Bray Standards Track [Page 6] > > RFC 7159 JSON March 2014 > > > An exponent part begins with the letter E in upper or lower case, which may be followed by a plus or minus sign. The E and optional which may be followed by a plus or minus sign. The E and optional sign are followed by one or more digits. sign are followed by one or more digits. Numeric values that cannot be represented as sequences of digits | Numeric values that cannot be represented in the grammar below (such (such as Infinity and NaN) are not permitted. | as Infinity and NaN) are not permitted. > number = [ minus ] int [ frac ] [ exp ] > decimal-point = %x2E ; . Crockford Informational [Page 3] | digit1-9 = %x31-39 ; 1-9 < RFC 4627 JSON July 2006 < > e = %x65 / %x45 ; e E number = [ minus ] int [ frac ] [ exp ] | exp = e [ minus / plus ] 1*DIGIT decimal-point = %x2E ; . | frac = decimal-point 1*DIGIT digit1-9 = %x31-39 ; 1-9 | int = zero / ( digit1-9 *DIGIT ) e = %x65 / %x45 ; e E | minus = %x2D ; - exp = e [ minus / plus ] 1*DIGIT | plus = %x2B ; + frac = decimal-point 1*DIGIT | zero = %x30 ; 0 int = zero / ( digit1-9 *DIGIT ) | This specification allows implementations to set limits on the range > and precision of numbers accepted. Since software that implements > IEEE 754-2008 binary64 (double precision) numbers [IEEE754] is > generally available and widely used, good interoperability can be > achieved by implementations that expect no more precision or range > than these provide, in the sense that implementations will > approximate JSON numbers within the expected precision. A JSON > number such as 1E400 or 3.141592653589793238462643383279 may indicate > potential interoperability problems, since it suggests that the > software that created it expects receiving software to have greater > capabilities for numeric magnitude and precision than is widely > available. minus = %x2D ; - | Note that when such software is used, numbers that are integers and > are in the range [-(2**53)+1, (2**53)-1] are interoperable in the > sense that implementations will agree exactly on their numeric > values. plus = %x2B ; + < zero = %x30 ; 0 | > > > > > Bray Standards Track [Page 7] > > RFC 7159 JSON March 2014 > =============================================================================================================================================================== 2.5. Strings | 7. Strings The representation of strings is similar to conventions used in the C The representation of strings is similar to conventions used in the C family of programming languages. A string begins and ends with family of programming languages. A string begins and ends with quotation marks. All Unicode characters may be placed within the quotation marks. All Unicode characters may be placed within the quotation marks except for the characters that must be escaped: | quotation marks, except for the characters that must be escaped: quotation mark, reverse solidus, and the control characters (U+0000 quotation mark, reverse solidus, and the control characters (U+0000 through U+001F). through U+001F). Any character may be escaped. If the character is in the Basic Any character may be escaped. If the character is in the Basic Multilingual Plane (U+0000 through U+FFFF), then it may be Multilingual Plane (U+0000 through U+FFFF), then it may be represented as a six-character sequence: a reverse solidus, followed represented as a six-character sequence: a reverse solidus, followed by the lowercase letter u, followed by four hexadecimal digits that by the lowercase letter u, followed by four hexadecimal digits that encode the character's code point. The hexadecimal letters A though encode the character's code point. The hexadecimal letters A though F can be upper or lowercase. So, for example, a string containing | F can be upper or lower case. So, for example, a string containing only a single reverse solidus character may be represented as only a single reverse solidus character may be represented as "\u005C". "\u005C". Alternatively, there are two-character sequence escape Alternatively, there are two-character sequence escape representations of some popular characters. So, for example, a representations of some popular characters. So, for example, a string containing only a single reverse solidus character may be string containing only a single reverse solidus character may be represented more compactly as "\\". represented more compactly as "\\". To escape an extended character that is not in the Basic Multilingual To escape an extended character that is not in the Basic Multilingual Plane, the character is represented as a twelve-character sequence, | Plane, the character is represented as a 12-character sequence, encoding the UTF-16 surrogate pair. So, for example, a string encoding the UTF-16 surrogate pair. So, for example, a string containing only the G clef character (U+1D11E) may be represented as containing only the G clef character (U+1D11E) may be represented as "\uD834\uDD1E". "\uD834\uDD1E". > string = quotation-mark *char quotation-mark > char = unescaped / > escape ( > %x22 / ; " quotation mark U+0022 > %x5C / ; \ reverse solidus U+005C > %x2F / ; / solidus U+002F > %x62 / ; b backspace U+0008 > %x66 / ; f form feed U+000C > %x6E / ; n line feed U+000A > %x72 / ; r carriage return U+000D > %x74 / ; t tab U+0009 > %x75 4HEXDIG ) ; uXXXX U+XXXX Crockford Informational [Page 4] | escape = %x5C ; \ < RFC 4627 JSON July 2006 < > quotation-mark = %x22 ; " string = quotation-mark *char quotation-mark | unescaped = %x20-21 / %x23-5B / %x5D-10FFFF char = unescaped / < escape ( < %x22 / ; " quotation mark U+0022 < %x5C / ; \ reverse solidus U+005C < %x2F / ; / solidus U+002F < %x62 / ; b backspace U+0008 < %x66 / ; f form feed U+000C < %x6E / ; n line feed U+000A < %x72 / ; r carriage return U+000D < %x74 / ; t tab U+0009 < %x75 4HEXDIG ) ; uXXXX U+XXXX < escape = %x5C ; \ < quotation-mark = %x22 ; " | Bray Standards Track [Page 8] > > RFC 7159 JSON March 2014 unescaped = %x20-21 / %x23-5B / %x5D-10FFFF < =============================================================================================================================================================== 3. Encoding | 8. String and Character Issues JSON text SHALL be encoded in Unicode. The default encoding is | 8.1. Character Encoding UTF-8. | > JSON text SHALL be encoded in UTF-8, UTF-16, or UTF-32. The default > encoding is UTF-8, and JSON texts that are encoded in UTF-8 are > interoperable in the sense that they will be read successfully by the > maximum number of implementations; there are many implementations > that cannot successfully read texts in other encodings (such as > UTF-16 and UTF-32). > > Implementations MUST NOT add a byte order mark to the beginning of a > JSON text. In the interests of interoperability, implementations > that parse JSON texts MAY ignore the presence of a byte order mark > rather than treating it as an error. > > 8.2. Unicode Characters > > When all the strings represented in a JSON text are composed entirely > of Unicode characters [UNICODE] (however escaped), then that JSON > text is interoperable in the sense that all software implementations > that parse it will agree on the contents of names and of string > values in objects and arrays. > > However, the ABNF in this specification allows member names and > string values to contain bit sequences that cannot encode Unicode > characters; for example, "\uDEAD" (a single unpaired UTF-16 > surrogate). Instances of this have been observed, for example, when > a library truncates a UTF-16 string without checking whether the > truncation split a surrogate pair. The behavior of software that > receives JSON texts containing such values is unpredictable; for > example, implementations might return different values for the length > of a string value or even suffer fatal runtime exceptions. > > 8.3. String Comparison > > Software implementations are typically required to test names of > object members for equality. Implementations that transform the > textual representation into sequences of Unicode code units and then > perform the comparison numerically, code unit by code unit, are > interoperable in the sense that implementations will agree in all > cases on equality or inequality of two strings. For example, > implementations that compare strings with escaped characters > unconverted may incorrectly find that "a\\b" and "a\u005Cb" are not > equal. > > > > > > > Bray Standards Track [Page 9] > > RFC 7159 JSON March 2014 Since the first two characters of a JSON text will always be ASCII < characters [RFC0020], it is possible to determine whether an octet < stream is UTF-8, UTF-16 (BE or LE), or UTF-32 (BE or LE) by looking < at the pattern of nulls in the first four octets. < < 00 00 00 xx UTF-32BE < 00 xx 00 xx UTF-16BE < xx 00 00 00 UTF-32LE < xx 00 xx 00 UTF-16LE < xx xx xx xx UTF-8 < =============================================================================================================================================================== 4. Parsers | 9. Parsers A JSON parser transforms a JSON text into another representation. A A JSON parser transforms a JSON text into another representation. A JSON parser MUST accept all texts that conform to the JSON grammar. JSON parser MUST accept all texts that conform to the JSON grammar. A JSON parser MAY accept non-JSON forms or extensions. A JSON parser MAY accept non-JSON forms or extensions. An implementation may set limits on the size of texts that it An implementation may set limits on the size of texts that it accepts. An implementation may set limits on the maximum depth of accepts. An implementation may set limits on the maximum depth of nesting. An implementation may set limits on the range of numbers. | nesting. An implementation may set limits on the range and precision An implementation may set limits on the length and character contents | of numbers. An implementation may set limits on the length and of strings. | character contents of strings. < < < < Crockford Informational [Page 5] < < RFC 4627 JSON July 2006 < < =============================================================================================================================================================== 5. Generators | 10. Generators A JSON generator produces JSON text. The resulting text MUST A JSON generator produces JSON text. The resulting text MUST strictly conform to the JSON grammar. strictly conform to the JSON grammar. =============================================================================================================================================================== 6. IANA Considerations | 11. IANA Considerations The MIME media type for JSON text is application/json. The MIME media type for JSON text is application/json. Type name: application | Type name: application Subtype name: json | Subtype name: json Required parameters: n/a | Required parameters: n/a Optional parameters: n/a | Optional parameters: n/a Encoding considerations: 8bit if UTF-8; binary if UTF-16 or UTF-32 | Encoding considerations: binary JSON may be represented using UTF-8, UTF-16, or UTF-32. When JSON | Security considerations: See [RFC7159], Section 12. is written in UTF-8, JSON is 8bit compatible. When JSON is < written in UTF-16 or UTF-32, the binary content-transfer-encoding < must be used. < Security considerations: | Interoperability considerations: Described in [RFC7159] Generally there are security issues with scripting languages. JSON | Published specification: [RFC7159] is a subset of JavaScript, but it is a safe subset that excludes < assignment and invocation. < A JSON text can be safely passed into JavaScript's eval() function | Applications that use this media type: (which compiles and executes a string) if all the characters not | JSON has been used to exchange data between applications written enclosed in strings are in the set of characters that form JSON | in all of these programming languages: ActionScript, C, C#, tokens. This can be quickly determined in JavaScript with two | Clojure, ColdFusion, Common Lisp, E, Erlang, Go, Java, JavaScript, regular expressions and calls to the test and replace methods. | Lua, Objective CAML, Perl, PHP, Python, Rebol, Ruby, Scala, and | Scheme. var my_JSON_object = !(/[^,:{}\[\]0-9.\-+Eaeflnr-u \n\r\t]/.test( < text.replace(/"(\\.|[^"\\])*"/g, ''))) && < eval('(' + text + ')'); < < Interoperability considerations: n/a < < Published specification: RFC 4627 < Crockford Informational [Page 6] | Bray Standards Track [Page 10] RFC 4627 JSON July 2006 | RFC 7159 JSON March 2014 < Applications that use this media type: < < JSON has been used to exchange data between applications written < in all of these programming languages: ActionScript, C, C#, < ColdFusion, Common Lisp, E, Erlang, Java, JavaScript, Lua, < Objective CAML, Perl, PHP, Python, Rebol, Ruby, and Scheme. < Additional information: Additional information: < Magic number(s): n/a Magic number(s): n/a File extension(s): .json File extension(s): .json Macintosh file type code(s): TEXT Macintosh file type code(s): TEXT Person & email address to contact for further information: Person & email address to contact for further information: Douglas Crockford | IESG douglas@crockford.com | Intended usage: COMMON | Intended usage: COMMON Restrictions on usage: none | Restrictions on usage: none Author: Author: Douglas Crockford Douglas Crockford douglas@crockford.com | Change controller: Change controller: Douglas Crockford | IESG douglas@crockford.com | > > Note: No "charset" parameter is defined for this registration. > Adding one really has no effect on compliant recipients. > > 12. Security Considerations > > Generally, there are security issues with scripting languages. JSON > is a subset of JavaScript but excludes assignment and invocation. 7. Security Considerations | Since JSON's syntax is borrowed from JavaScript, it is possible to > use that language's "eval()" function to parse JSON texts. This > generally constitutes an unacceptable security risk, since the text > could contain executable code along with data declarations. The same > consideration applies to the use of eval()-like functions in any > other programming language in which JSON texts conform to that > language's syntax. > > > > > > > > > > > > > > > > Bray Standards Track [Page 11] > > RFC 7159 JSON March 2014 See Security Considerations in Section 6. < =============================================================================================================================================================== 8. Examples | 13. Examples This is a JSON object: This is a JSON object: { | { "Image": { | "Image": { "Width": 800, | "Width": 800, "Height": 600, | "Height": 600, "Title": "View from 15th Floor", | "Title": "View from 15th Floor", "Thumbnail": { | "Thumbnail": { "Url": "http://www.example.com/image/481989943", | "Url": "http://www.example.com/image/481989943", "Height": 125, | "Height": 125, "Width": "100" | "Width": 100 }, | }, "IDs": [116, 943, 234, 38793] | "Animated" : false, > "IDs": [116, 943, 234, 38793] > } > } > > Its Image member is an object whose Thumbnail member is an object and > whose IDs member is an array of numbers. > > This is a JSON array containing two objects: > > [ > { > "precision": "zip", > "Latitude": 37.7668, > "Longitude": -122.3959, > "Address": "", > "City": "SAN FRANCISCO", > "State": "CA", > "Zip": "94107", > "Country": "US" > }, > { > "precision": "zip", > "Latitude": 37.371991, > "Longitude": -122.026020, > "Address": "", > "City": "SUNNYVALE", > "State": "CA", > "Zip": "94085", > "Country": "US" > } > ] Crockford Informational [Page 7] | > > Bray Standards Track [Page 12] RFC 4627 JSON July 2006 | RFC 7159 JSON March 2014 } | Here are three small JSON texts containing only values: } < Its Image member is an object whose Thumbnail member is an object | "Hello world!" and whose IDs member is an array of numbers. < This is a JSON array containing two objects: | 42 [ | true { < "precision": "zip", < "Latitude": 37.7668, < "Longitude": -122.3959, < "Address": "", < "City": "SAN FRANCISCO", < "State": "CA", < "Zip": "94107", < "Country": "US" < }, < { < "precision": "zip", < "Latitude": 37.371991, < "Longitude": -122.026020, < "Address": "", < "City": "SUNNYVALE", < "State": "CA", < "Zip": "94085", < "Country": "US" < } < ] < =============================================================================================================================================================== 9. References | 14. Contributors 9.1. Normative References | RFC 4627 was written by Douglas Crockford. This document was > constructed by making a relatively small number of changes to that > document; thus, the vast majority of the text here is his. [ECMA] European Computer Manufacturers Association, "ECMAScript | 15. References Language Specification 3rd Edition", December 1999, < . < [RFC0020] Cerf, V., "ASCII format for network interchange", RFC 20, | 15.1. Normative References October 1969. < [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate | [IEEE754] IEEE, "IEEE Standard for Floating-Point Arithmetic", IEEE Requirement Levels", BCP 14, RFC 2119, March 1997. | Standard 754, August 2008, > . [RFC4234] Crocker, D. and P. Overell, "Augmented BNF for Syntax | [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Specifications: ABNF", RFC 4234, October 2005. | Requirement Levels", BCP 14, RFC 2119, March 1997. > [RFC5234] Crocker, D. and P. Overell, "Augmented BNF for Syntax > Specifications: ABNF", STD 68, RFC 5234, January 2008. > [UNICODE] The Unicode Consortium, "The Unicode Standard", > . Crockford Informational [Page 8] | 15.2. Informative References > > [ECMA-262] Ecma International, "ECMAScript Language Specification > Edition 5.1", Standard ECMA-262, June 2011, > Ecma-262.htm>. > > [ECMA-404] Ecma International, "The JSON Data Interchange Format", > Standard ECMA-404, October 2013, > Ecma-404.htm>. > > [Err3607] RFC Errata, Errata ID 3607, RFC 3607, > . > > > > > > > Bray Standards Track [Page 13] RFC 4627 JSON July 2006 | RFC 7159 JSON March 2014 > > > [Err607] RFC Errata, Errata ID 607, RFC 607, > . > > [RFC4627] Crockford, D., "The application/json Media Type for > JavaScript Object Notation (JSON)", RFC 4627, July 2006. > > > > > > > > > > > > > > > > > [UNICODE] The Unicode Consortium, "The Unicode Standard Version 4.0", | 2003, . | > > > > > > > > > > > > > > > > > > > > > > > > > > Bray Standards Track [Page 14] > > RFC 7159 JSON March 2014 > =============================================================================================================================================================== Author's Address | Appendix A. Changes from RFC 4627 > > This section lists changes between this document and the text in RFC > 4627. > > o Changed the title and abstract of the document. > > o Changed the reference to [UNICODE] to be not version specific. > > o Added a "Specifications of JSON" section. Douglas Crockford | o Added an "Introduction to This Revision" section. JSON.org < EMail: douglas@crockford.com < > o Changed the definition of "JSON text" so that it can be any JSON > value, removing the constraint that it be an object or array. > o Added language about duplicate object member names, member > ordering, and interoperability. > o Clarified the absence of a requirement that values in an array be > of the same JSON type. > o Applied erratum #607 from RFC 4627 to correctly align the artwork > for the definition of "object". > o Changed "as sequences of digits" to "in the grammar below" in the > "Numbers" section, and made base-10-ness explicit. > o Added language about number interoperability as a function of > IEEE754, and added an IEEE754 reference. > o Added language about interoperability and Unicode characters and > about string comparisons. To do this, turned the old "Encoding" > section into a "String and Character Issues" section, with three > subsections: "Character Encoding", "Unicode Characters", and > "String Comparison". > o Changed guidance in the "Parsers" section to point out that > implementations may set limits on the range "and precision" of > numbers. > o Updated and tidied the "IANA Considerations" section. > o Made a real "Security Considerations" section and lifted the text > out of the previous "IANA Considerations" section. > Bray Standards Track [Page 15] > > RFC 7159 JSON March 2014 > o Applied erratum #3607 from RFC 4627 by removing the security > consideration that begins "A JSON text can be safely passed" and > the JavaScript code that went with that consideration. > o Added a note to the "Security Considerations" section pointing out > the risks of using the "eval()" function in JavaScript or any > other language in which JSON texts conform to that language's > syntax. > o Added a note to the "IANA Considerations" clarifying the absence > of a "charset" parameter for the application/json media type. > o Changed "100" to 100 and added a boolean field, both in the first > example. > o Added examples of JSON texts with simple values, neither objects > nor arrays. > > o Added a "Contributors" section crediting Douglas Crockford. > > o Added a reference to RFC 4627. > > o Moved the ECMAScript reference from Normative to Informative and > updated it to reference ECMAScript 5.1, and added a reference to > ECMA 404. > > Author's Address > Tim Bray (editor) > Google, Inc. > EMail: tbray@textuality.com Crockford Informational [Page 9] | Bray Standards Track [Page 16] > ===============================================================================================================================================================