Internet Engineering Task Force P. THOMY Internet-Draft Loco-labs Intended status: Informational 27 May 2024 Expires: 28 November 2024 JSON semantic format (JSON-NTV) draft-thomy-json-ntv-03 Abstract This document describes a set of simple rules for unambiguously and concisely encoding semantic data into JSON Data Interchange Format. These rules are based on an NTV (Named and Typed Values) data structure applicable to any simple or complex data. The JSON-NTV format is its JSON translation. 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 https://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 28 November 2024. Copyright Notice Copyright (c) 2024 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 (https://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 Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License. THOMY Expires 28 November 2024 [Page 1] Internet-Draft JSON semantic format (JSON-NTV) May 2024 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1. Presentation . . . . . . . . . . . . . . . . . . . . . . 3 1.2. Key design features . . . . . . . . . . . . . . . . . . . 4 1.3. Conventions Used in This Document . . . . . . . . . . . . 5 2. NTV structure . . . . . . . . . . . . . . . . . . . . . . . . 6 2.1. NTV layers . . . . . . . . . . . . . . . . . . . . . . . 6 2.2. NTV entities . . . . . . . . . . . . . . . . . . . . . . 7 2.2.1. NTVsingle . . . . . . . . . . . . . . . . . . . . . . 7 2.2.2. NTVlist . . . . . . . . . . . . . . . . . . . . . . . 8 2.3. DataType and Namespace . . . . . . . . . . . . . . . . . 8 2.3.1. Namespace . . . . . . . . . . . . . . . . . . . . . . 9 2.3.2. DataType . . . . . . . . . . . . . . . . . . . . . . 9 2.3.3. Representation . . . . . . . . . . . . . . . . . . . 10 3. JsonNTV . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.1. JsonNTV format . . . . . . . . . . . . . . . . . . . . . 11 3.2. JsonNTVname . . . . . . . . . . . . . . . . . . . . . . . 13 3.3. JsonNTVtype . . . . . . . . . . . . . . . . . . . . . . . 13 3.4. JsonNTVvalue . . . . . . . . . . . . . . . . . . . . . . 14 4. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 15 5. Parsing a JsonValue . . . . . . . . . . . . . . . . . . . . . 17 5.1. JSON decoding . . . . . . . . . . . . . . . . . . . . . . 18 5.2. NTV entity decoding . . . . . . . . . . . . . . . . . . . 18 5.3. NTVvalue decoding . . . . . . . . . . . . . . . . . . . . 19 5.4. NTVtype decoding . . . . . . . . . . . . . . . . . . . . 19 6. Properties . . . . . . . . . . . . . . . . . . . . . . . . . 20 6.1. NTV tree . . . . . . . . . . . . . . . . . . . . . . . . 20 6.2. NTV Pointer . . . . . . . . . . . . . . . . . . . . . . . 20 6.3. NTV Comparison . . . . . . . . . . . . . . . . . . . . . 21 6.4. NTV Canonical . . . . . . . . . . . . . . . . . . . . . . 22 6.5. JSON as a subtype of NTV . . . . . . . . . . . . . . . . 22 6.6. extended NTV structure . . . . . . . . . . . . . . . . . 23 6.7. nested NTVsingle entities . . . . . . . . . . . . . . . . 23 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 24 8. Security Considerations . . . . . . . . . . . . . . . . . . . 25 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 25 9.1. Normative References . . . . . . . . . . . . . . . . . . 25 9.2. Informative References . . . . . . . . . . . . . . . . . 26 Appendix A. Global DataType and Namespace . . . . . . . . . . . 26 A.1. Json . . . . . . . . . . . . . . . . . . . . . . . . . . 27 A.2. Numbers . . . . . . . . . . . . . . . . . . . . . . . . . 27 A.3. Binary encoding . . . . . . . . . . . . . . . . . . . . . 28 A.4. Datation . . . . . . . . . . . . . . . . . . . . . . . . 28 A.5. Period and Duration . . . . . . . . . . . . . . . . . . . 30 A.6. Location . . . . . . . . . . . . . . . . . . . . . . . . 30 A.7. Structured data . . . . . . . . . . . . . . . . . . . . . 32 A.8. Normalized String . . . . . . . . . . . . . . . . . . . . 32 THOMY Expires 28 November 2024 [Page 2] Internet-Draft JSON semantic format (JSON-NTV) May 2024 A.9. Namespace . . . . . . . . . . . . . . . . . . . . . . . . 34 A.10. Custom DataType and Namespace . . . . . . . . . . . . . . 34 Appendix B. Complete ABNF notation . . . . . . . . . . . . . . . 35 Appendix C. JSON-NTV equivalence . . . . . . . . . . . . . . . . 37 Appendix D. Mapping DataTypes . . . . . . . . . . . . . . . . . 39 D.1. Table-Schema . . . . . . . . . . . . . . . . . . . . . . 39 D.2. JSON Schema . . . . . . . . . . . . . . . . . . . . . . . 40 D.3. YANG . . . . . . . . . . . . . . . . . . . . . . . . . . 42 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 42 Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 42 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 43 1. Introduction 1.1. Presentation The semantic level of JSON or CSV shared data remains low. It is often limited to the type of data defined in those exchange formats (strings for CSV formats; numbers, strings, arrays and objects for JSON formats). JSON-NTV proposes to increase the semantic level of the JSON entities [RFC8259] by adding two additional pieces of information to a JSON entity : * *name*: interpretation of the JSON value in human language or detailed information or link to external information, * *type*: interpretation of the JSON value in a data standard (eg. GeoJSON, datetime), in a data catalog or in a software language. The NTV entity is thus a triplet with a mandatory element (value) and two additional elements (name, type). _For example, Paris location can be represented by :_ - _a name : "paris",_ - _a type : geoJSON Point coordinates [RFC7946],_ - _a value : [2.3522, 48.8566]_ The easiest way to add that information into a JSON value is to use a JSON object with a single member. The first term is the additional elements using the syntax JSON-ND [JSON-ND]. The second term is the JSON value. _The JSON value of the previous example is:_ _{ "paris:point" : [2.3522, 48.8566] }_ THOMY Expires 28 November 2024 [Page 3] Internet-Draft JSON semantic format (JSON-NTV) May 2024 With this approach, two NTV entities are defined : * *a primitive entity* which is not composed of any other entity, * *a structured entity* which is an ordered sequence of NTV entities. as well as two JSON formats depending on the presence of the additional elements : * *simple format* when name and type are not present * *named format* when name or type is present _Example (entity composed of two other primitive entities):_ _{ "cities::point": [[2.3522, 48.8566], [4.8357, 45.7640]] } simple format for primitive entities_ _{"cities::point": {"paris":[2.3522, 48.8566], "lyon":[4.8357, 45.7640]}} named format for primitive entities_ A JSON-NTV generator produces a JSON value from a NTV entity and vice versa a JSON-NTV parser transforms a JSON value into a NTV entity. The document [NTV-TAB] presents a variation of this format for tabular and multidimensional data. The conversion between NTV entity and native entity is outside the scope of this note. 1.2. Key design features The format is focused on simplicity, lightness and web usage. The key features of this format are the following: * *JSON as the base format* - JSON is simple and readable as simple text - JSON supports rich structure including nesting and basic types - JSON is web-native and very widely used and supported - JSON format has binary representation (eg. CBOR format) * *high semantic level of data* THOMY Expires 28 November 2024 [Page 4] Internet-Draft JSON semantic format (JSON-NTV) May 2024 - wide variety of data typing - tree-like and customisable data typing * *compatibility with existing formats* - All JSON data is a JsonNTV data - All NTVtypes are standard types * *compatibility with any type of platform* - types and structures are independent of software and hardware platforms - the NTV concept is applicable to all types of "jsonable" data * *reversibility* - the NTV entity coming from a JSON value is identical to the NTV entity from which the JSON value comes - the JSON representation of an NTV entity is the same as the JSON value used to construct the NTV entity * *tree structure* - all NTV entities are trees - tree properties are applicable to NTV entities 1.3. Conventions Used in This Document The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here. This document also uses the following terms: *JsonText, JsonMember, JsonElement :* These terms are defined as text, member, element in the JSON grammar [RFC8174]. THOMY Expires 28 November 2024 [Page 5] Internet-Draft JSON semantic format (JSON-NTV) May 2024 *JsonValue, JsonObject, JsonArray, JsonNumber, JsonString, JsonFalse, JsonNull, JsonTrue:* These terms correspond to entities whose representation is defined as value, object, array, number, string, false, null, true in the JSON grammar [RFC8174]. *JsonPrimitive:* A JsonNumber, JsonString, JsonFalse, JsonTrue or JsonNull. *JsonUnnamed:* A JsonObject without a single member. *JsonNamed:* A JsonObject with a single member. *NTVsingle, NTVlist:* NTVlist and NTVsingle entities can be abbreviated as: * NVsingle : entity with default NTVtype "json", * NVlist : entity without NTVtype, * TVsingle, TVlist : entity without NTVname, * Vsingle, Vlist : NVsingle or NVlist without NTVname. 2. NTV structure 2.1. NTV layers NTV and JsonNTV structures are defined as shown in Figure 1: * NTV is a data triplet (NTVname, NTVtype, NTVvalue) that contains all the information needed to build the native entity. * JsonNTV is the JsonValue of the NTV entity. JsonNTV is used to build an interchangeable JsonText +--------+ JSON load +-------+ NTV load +-------+ to_obj +------+ | |---------->| |--------->| NTV |--------->|native| |JsonText| |JsonNTV| |triplet| |entity| | |<----------| |<---------| |<---------| | +--------+ JSON dump +-------+ NTV dump +-------+ from_obj +------+ Figure 1: NTV layers _Example:_ THOMY Expires 28 November 2024 [Page 6] Internet-Draft JSON semantic format (JSON-NTV) May 2024 * _Native layer_ new_year_2022 = datetime.date(2022, 01, 01) _is a Python variable "new_year_2022" corresponding to a datetime object_ * _NTV layer_ ("new_year_2022", "date", "2022-01-01") _is a triplet_ * _JsonNTV layer_ { "new_year_2022:date" : "2022-01-01" } _is a JsonValue_ * _JsonText layer_ '{"new_year_2022:date":"2022-01-01"}' _is a JsonString_ 2.2. NTV entities Two categories of entities (one primitive and one structured) are defined: * *NTVsingle* for the primitive entity, * *NTVlist* for an ordered sequence of NTV entities An NTV entity is therefore a tree where the leaves nodes are the NTVsingle entities and where the inner nodes are the NTVlist entities 2.2.1. NTVsingle The data triplet of NTVsingle entities is composed by: * *NTVsingleValue*: This NTVvalue is the JSON representation (JsonValue) of the main content of the NTV entity, * *NTVsingleType*: This NTVtype is a DataType. It defines the type of entity and the conversion rules between the native entity and the NTV entity. The default NTVtype (defaultNTVtype) is the "json" DataType. * *NTVname*: The NTVname is an additional textual information (JsonString) *In other words, any entity that has on the one hand a function of encoding it into a JsonValue and on the other hand a function of creating from a JsonValue can be taken into account. This approach is very general because the majority of computer objects are defined THOMY Expires 28 November 2024 [Page 7] Internet-Draft JSON semantic format (JSON-NTV) May 2024 by a list of parameters (e.g. *args in python) and/or a list of key/ values (e.g. **kwargs in python) which simply translate into a JsonArray or a JsonObject.* The consistency between NTVsingleValue and NTVsingleType is outside the scope of this note. 2.2.2. NTVlist The data triplet of NTVlist entities is composed by: * *NTVlistValue*: This NTVvalue is an ordered sequence of included NTV entities. * *NTVlistType*: This NTVtype is a Namespace or a DataType to apply to the NTV entities included. This NTVlistType avoids including a NTVtype (if DataType) or reduces the length (if Namespace) in the JSON representation (JsonNTV) of the included NTV entities. The default NTVtype (defaultNTVtype) is "None". * *NTVname*: The NTVname is an additional textual information (JsonString) _Example of equivalent JSON representations:_ _where NTVlistType is None for the global NTVlist_ _[ { ":point" : [2.3522, 48.8566]}, {":point" : [4.8357, 45.7640]} ]_ _where NTVlistType is "point" for the global NTVlist_ _{ "::point" : [ [2.3522, 48.8566], [4.8357, 45.7640] ] }_ _If JsonValue is { "::dat" : ["2022-01-28T18-23-54", {":point": [1.1, 2.2] ] } }, the parsers deduce that the first NTVvalue has a "dat" NTVtype and the second a "point" NTVtype._ 2.3. DataType and Namespace A DataType is defined in a nested structure called Namespace. This structuring of type makes it possible to reference any type of data that has a JSON representation and to consolidate all the shared data structures within the same tree of types. THOMY Expires 28 November 2024 [Page 8] Internet-Draft JSON semantic format (JSON-NTV) May 2024 2.3.1. Namespace A Namespace is defined by a name (NamespaceName) and a Namespace parent (NamespaceParent). The NamespaceName is unique in the NamespaceParent. Root node in the Namespace tree is the GlobalNamespace. REQ1: NamespaceParent of GlobalNamespace is None. 2.3.2. DataType The DataType represents the semantic of a data and is structured in a flat classification. For example, "email" and "string" are two DataType. A DataType is composed with a TypeBase and an optional TypeExtension. The TypeExtension defines an additional property. For example: * a "float" TypeBase may have a "kg" extension to indicate a unit. * a "string" TypeBase may have a "fr" extension to indicate a langage. A DataType is defined by a name (DataTypeName) and a Namespace parent (NamespaceParent). The TypeBase of a DataType is unique in the NamespaceParent. The TypeExtension of a DataType is free. TypeBase and the rules to encode or decode NTVvalues MUST be understood by data producers and data consumers. So TypeBase and rules associated have to be defined in a specification shared by a large community. On the other hand, it must be possible for everyone to share data according to their own data structure. There are therefore two categories of TypeBase: * custom TypeBase (and Namespace) which can be created by anyone without control, * shared TypeBase (and Namespace) that are defined in a single, shared repository. Each 'shared' Namespace or TypeBase is uniquely managed. For shared TypeBase, three sub-categories are defined (None, Simple, Generic). * The "None" TypeBase is used with NTVlist as defaultDataType. THOMY Expires 28 November 2024 [Page 9] Internet-Draft JSON semantic format (JSON-NTV) May 2024 * Simple TypeBase is associated to conversion rules between a native entity and a NTV entity. * Generic TypeBase is equivalent to a set of Simple TypeBase. This indicates that parsers use associated simple TypeBase to decode the JsonNTVvalue. _Example:_ _"dat" is the generic TypeBaseName for "datetime" and "timeposix"_ _If a JSONvalue is { "::dat" : ["2022-01-28T18-23-54", 123456.78] }, the parser deduces that the first entity has a "datetime" TypeBaseName and the second a "timeposix" TypeBaseName._ 2.3.3. Representation A Namespace is defined by a string followed by a point (NamespaceName). A DataType is defined by a string (DataTypeName) composed by the TypeBaseName and the TypeExtensionName. The representation of a Namespace (NamespaceLongName) is composed by all the nested NamespaceName. The representation of a DataType (DataTypeLongName) is composed by the NamespaceLongName and the DataTypeName. The DataTypeLongName is defined in Figure 2, which uses ABNF from [RFC5234]. ; representation of DataType and Namespace (Name and LongName) DataTypeLongName = NamespaceParentLongName DataTypeName NamespaceLongName = NamespaceParentLongName NamespaceName NamespaceParentLongName = NamespaceLongName NamespaceName = [ ["$"] JsonString "." ] ; REQ2 REQ3 DataTypeName = TypeBaseName ["[" TypeExtensionName "]"] TypeBaseName = ["$"] JsonString ; REQ3 TypeExtensionName = JsonString Figure 2: DataType and Namespace names - ABNF The corresponding rules are as follows: THOMY Expires 28 November 2024 [Page 10] Internet-Draft JSON semantic format (JSON-NTV) May 2024 REQ2: NamespaceName and NamespaceLongName of GlobalNamespace are empty. REQ3: DataType (or Namespace) has 'custom' category if DataTypeName (or NamespaceName) begins with '$' or NamespaceParent has 'custom' category _Example for a representation of a DataType defined in two nested Namespace in the global Namespace:_ _"ns1.ns2.type"_ _where:_ _"ns1." is a NamespaceName of a Namespace defined in the global Namespace,_ _"ns2." is a NamespaceName of a Namespace defined in the "ns1" Namespace,_ _"type" is a DataTypeName of a DataType defined in the "ns2" Namespace_ _Example of custom categories:_ _If "fr." is the name of a Namespace attached to the global Namespace and containing the Namespace 'BAN' and the DataType 'dep', then:_ - _"fr.dep" is a name of a shared DataType,_ - _"fr.$test" is a name of a custom DataType,_ - _"fr.$example.one" is a name of a custom DataType_ - _"fr.BAN.$test" is a name of a custom DataType_ 3. JsonNTV 3.1. JsonNTV format The JsonNTV format is the JSON representation of an NTV entity (JsonValue). This JsonValue is converted in JsonText with a Json generator. The JsonNTV format is defined in Figure 3, which uses ABNF from [RFC5234]. THOMY Expires 28 November 2024 [Page 11] Internet-Draft JSON semantic format (JSON-NTV) May 2024 ; JSON representation of NTV entities (JsonNTV) JsonNTV = JsonNTVnamed / JsonNTVsimple ; REQ4 JsonNTVnamed = beginObject JsonNTVMember endObject JsonNTVsimple = JsonNTVvalue JsonNTVMember = JsonNTVname nSep JsonNTVvalue ; Extract of JSON grammar used in this document beginArray = ws "[" ws beginObject = ws "{" ws endArray = ws "]" ws endObject = ws "}" ws nSep = ws ":" ws vSep = ws "," ws ws = *( %x20 / %x09 / %x0A / %x0D ) JsonValue = JsonValue ; indicates that rule is defined in RFC8259 JsonString = JsonString ; indicates that rule is defined in RFC8259 Figure 3: JsonNTV - ABNF The JsonNTV format is built with the NTVname, NTVvalue and the JsonNTVtype. Two JsonNTV formats are defined: * named format: _{ JsonNTVname : JsonNTVvalue }_ * simple format: _JsonNTVvalue_ The corresponding rule is as follows: REQ4: If JsonNTVname is empty, simple format is used else named format is used _Note :_ * _JsonNTV : 21, { ":" : 21 } and { ":json" : 21 } represent the same Vsingle entity._ THOMY Expires 28 November 2024 [Page 12] Internet-Draft JSON semantic format (JSON-NTV) May 2024 * _If JsonNTVvalue is a JsonObject with a single member, the JsonNTVname is not empty._ 3.2. JsonNTVname JsonNTVname is the concatenation of NTVname and JsonSepType. JsonSepType is composed with the separator singleSep or listSep and the JsonNTVtype. JsonNTVname and JsonSepType are defined in Figure 4, which uses ABNF from [RFC5234]. ; JSON representation of NTVname and NTVtype (JsonNTVname) JsonNTVname = NTVname JsonSepType JsonSepType = [singleSep [JsonNTVtype]]/([listSep] JsonNTVtype) ; REQ5 REQ6 NTVname = JsonString singleSep = ":" ; NTVsingle separator listSep = "::" ; NTVlist separator Figure 4: JsonNTVname - ABNF For NTVsingle entities: REQ5: If JsonNTVtype is not "json", JsonSepType is identical to singleSep joined with JsonNTVtype, else if JsonNTVvalue is not a JsonArray and not a JsonObject, JsonSepType is empty, else JsonSepType is identical to singleSep. For NTVlist entities: REQ6: If NTVtype is a DataType, listSep is present in JsonSepType else listSep is not present. 3.3. JsonNTVtype The JSON representation of a NTVtype (JsonNTVtype) is a compact representation of the NTVtype in the context of the NTVtypeParent. THOMY Expires 28 November 2024 [Page 13] Internet-Draft JSON semantic format (JSON-NTV) May 2024 The JsonNTVtype is defined in Figure 5, which uses ABNF from [RFC5234]. ; JSON representation of NTVType (JsonNTVtype) JsonNTVtype = [ NTVtypeLongName / NTVtypeRelativeName ] ; REQ7 NTVtypeLongName = DataTypeLongName / NamespaceLongName NTVtypeRelativeName = *NamespaceName (DataTypeName / NamespaceName) ; REQ7 Figure 5: JsonNTVtype - ABNF The corresponding rules are as follows: REQ7: if NTVtype is identical to NTVtypeParent, JsonNTVtype is empty, else if NTVtypeParent is a Namespace and if NTVtype is including in NTVtypeParent, JsonNTVtype is the NTVtypeRelativeName (relative to the NTVtypeParent), else JsonNTVtype is the NTVtypeLongName _Example:_ _If "fr." is the name of a Namespace attached to the global Namespace and containing the DataType 'dep', then:_ - _{ "::fr." : { "department1:dep": "name1", "department2:dep": "name2" } } is a valid JsonNTV representation._ 3.4. JsonNTVvalue The JsonNTVvalue is the JsonValue representation of NTVvalue as defined in Figure 6, which uses ABNF from [RFC5234]. THOMY Expires 28 November 2024 [Page 14] Internet-Draft JSON semantic format (JSON-NTV) May 2024 ; JSON representation of NTVvalue (JsonNTVvalue) JsonNTVvalue = JsonNTVsingleValue / JsonNTVlistValue JsonNTVsingleValue = NTVsingleValue JsonNTVlistValue = JsonNTVarrayValue / JsonNTVobjectValue ; REQ8 REQ9 JsonNTVarrayValue = beginArray ListJsonNTVvalue endArray ListJsonNTVvalue = [JsonNTV *( vSep JsonNTV )] JsonNTVobjectValue = beginObject ListJsonNTVmember endObject ListJsonNTVmember = [JsonNTVMember *( vSep JsonNTVMember)] NTVsingleValue = JsonValue Figure 6: JsonNTVvalue - ABNF For a NTVsingle, JsonNTVvalue is the NTVvalue. For a NTVlist, JsonNTValue has two representations: * a JsonArray where JsonElements are the JsonNTV of included NTV entities, * a JsonObject where the JsonMembers are the JsonMembers of the JsonNTV of included NTV entities. The corresponding rules are as follows: REQ8: NTVlist with multiple NTV entities : if all JsonNTVname of NTV entities are different and not empty, JsonNTVobjectValue is used else JsonNTVarrayValue is used REQ9: NTVlist with single NTV entity : if JsonNTVname of the NTVlist is not empty JsonNTVobjectValue is used else JsonNTVarrayValue is used _Example:_ _{ ":point" : [2.3522, 48.8566], ":point" : [4.8357, 45.7640] } is not a valid JsonNTV_ 4. Examples Examples of JsonNTV representation of NTV entities: *Vsingle :* THOMY Expires 28 November 2024 [Page 15] Internet-Draft JSON semantic format (JSON-NTV) May 2024 _"lyon"_ _52.5_ _{ ":" : [4.8357, 45.7640] }_ *NVsingle :* _{ "city" : "paris" }_ _{ "paris:" : [4.8357, 45.7640] }_ *TVsingle:* _{ ":point" : [4.8357, 45.7640] }_ _{ ":string[fr]" : "Paris est un belle ville" }_ *NTVsingle:* _{ "paris:point" : [2.3522, 48.8566] }_ _{ "paris:ntv" : { "coordinate:point" : [4.8357, 45.7640] } }_ *Vlist (composed with JsonArray):* _[4, 45]_ _["paris"]_ _[ [2.3522, 48.8566], {"lyon" : [4.8357, 45.7640]} ]_ _[ { ":point" : [2.3522, 48.8566]}, {":point" : [4.8357, 45.7640]} ]_ _[]_ *Vlist (composed with JsonObject) :* _{ "name": "white", "firstname":"walter", "surname":"heisenberg" }_ _{ "paris:point" : [2.3522, 48.8566] , "lyon" : "france"}_ _{ "paris" : [2.3522, 48.8566], "" : [4.8357, 45.7640]}_ _{ }_ THOMY Expires 28 November 2024 [Page 16] Internet-Draft JSON semantic format (JSON-NTV) May 2024 *NVlist :* _{ "simple list": [4, 45.7]}_ _{ "cities": [{":point": [2.3522, 48.8566]}, {":point": [4.8357, 45.7640]}]}_ *TVlist :* _{ "::point": [[2.3522, 48.8566], {"lyon" : [4.8357, 45.7640]} ] }_ _{ "::dat": [ "2022-01-28T18-23-54Z", "2022-01-28", 1234.78 ] }_ *NTVlist :* _{ "cities::point": [[2.3522, 48.8566], {"lyon": [4.8357, 45.7640]}] }_ _{ "generic date::dat": [ "2022-01-28T18-23-54Z", "2022-01-28", 1234.78]}_ _{ "various::point": [ [2.3, 48.8], { ":date": "2022-01-28"}, {":json": 25 }, { "another NTVlist::json": [1,2,3]} ]}_ *NTVlist and NVlist (composed with JsonObject) :* _{ "cities::point": { "paris": [2.352, 48.856], "lyon": [4.835, 45.764]}}_ _{ "cities": {"paris:point": [2.3522, 48.8566] , "lyon": "france"}}_ 5. Parsing a JsonValue JsonValue is parsed according to JSON structure (from root to leaves). Several steps are considered: * JSON decoding * NTV entity decoding * NTVvalue decoding * NTVtype decoding THOMY Expires 28 November 2024 [Page 17] Internet-Draft JSON semantic format (JSON-NTV) May 2024 5.1. JSON decoding This part is not detailed and consists of: * exploit the JSON structure to identify JsonNTVname and JsonNTVvalue, * extract the following data from the JsonNTVname string: JsonNTVtype, NTVname and singleSep or listSep 5.2. NTV entity decoding The NTV entity is inferred from the JSON structure of JsonValue or JsonNTVvalue: PARS1: The tables Table 1 and Table 2 define the entity identification rules (NTVsingle or NTVlist) +===============+=============+ | JsonValue | NTV entity | +===============+=============+ | JsonPrimitive | Vsingle | +---------------+-------------+ | JsonUnnamed | Vlist | +---------------+-------------+ | JsonArray | Vlist | +---------------+-------------+ | JsonNamed | see Table 2 | +---------------+-------------+ Table 1: Decoding JsonValue THOMY Expires 28 November 2024 [Page 18] Internet-Draft JSON semantic format (JSON-NTV) May 2024 +===========+===============+=============================+ | Separator | JsonNTVvalue | NTV entity | +===========+===============+=============================+ | None | JsonPrimitive | NVsingle | +-----------+---------------+-----------------------------+ | None | JsonNamed | NVsingle | +-----------+---------------+-----------------------------+ | None | JsonUnnamed | NVlist | +-----------+---------------+-----------------------------+ | None | JsonArray | NVlist | +-----------+---------------+-----------------------------+ | ":" | JsonValue | TVsingle or NTVSingle | +-----------+---------------+-----------------------------+ | "::" | JsonUnnamed | NVlist or TVlist or NTVlist | +-----------+---------------+-----------------------------+ | "::" | JsonArray | NVlist or TVlist or NTVlist | +-----------+---------------+-----------------------------+ Table 2: Decoding JsonNTVvalue 5.3. NTVvalue decoding The NTVvalue is inferred from the JsonNTVvalue: PARS2: The NTVvalue of NTVsingle is the JsonNTVvalue. PARS3: The NTVvalue of NTVlist is the list of NTV entities parsed for each JsonElement or JsonMember including in the JsonNTVvalue. 5.4. NTVtype decoding NTVtype is inferred from the JsonNTVtype: PARS4: If JsonNTVtype is a valid NTVtypeLongName : NTVtype is the decoded JsonNTVtype, else if concatened ParentNTVtypeLongName with JsonNTVtype is empty : NTVtype is "json", else if the decoded of concatenation of ParentNTVtypeLongName with JsonNTVtype is a valid NTVtypeLongName : NTVtype is it, else NTVtype is the defaultNTVtype The [JSON-NTV] repository gives some examples of NTV usage. THOMY Expires 28 November 2024 [Page 19] Internet-Draft JSON semantic format (JSON-NTV) May 2024 6. Properties 6.1. NTV tree An NTV entity is a tree where the leaf nodes are the NTVsingle entities and where the inner nodes are the NTVlist entities. Therefore the tree property are applicable: * tree indicators can be calculate: - breadth : number of NTVsingle entities (leaves) - size : number of NTV entities (nodes) - height : length of the longest downward path to a leaf * An ordering list of nodes can be defined to explore the tree for example according to the DFS pre-ordering algorithm[DFS] (this order is the same as the order in a JsonValue ), 6.2. NTV Pointer A NTV Pointer is a string syntax for identifying a specific NTV entity within a NTV tree. The syntax defined for JSON Pointer [RFC6901] (json-pointer, reference-token) is transposable to NTV Pointer (ntv-pointer, reference-token): * The ntv-pointer is a Unicode string containing a sequence of zero or more reference-tokens, each prefixed by a '/'. * The reference-token is the NTVname if it exists otherwise the zero-based index of the NTV entity in the NTVvalue list. The ntv-pointer is equal to the json-pointer of the JsonNTV representation in most cases except : * if the JsonNTV is a JsonObject with a single member where the value is a JsonPrimitive, * - if the JsonNTV contains a JsonArray containing a JsonObject with a single member where the value is a JsonPrimitive THOMY Expires 28 November 2024 [Page 20] Internet-Draft JSON semantic format (JSON-NTV) May 2024 6.3. NTV Comparison Three levels of equality are defined. *Strict equality:* Two NTV entities are strictly equals if : - the NTVname are identical - the NTVtypes are identical - the NTVvalue are identical o if the NTVvalue is a list of NTV entities, each NTV entity has to be identical o if the NTVvalue is a JSONvalue, the JSONvalues have to be identical *Structural equality:* Two NTV entities are structurally equals if : - the NTVname are identical - the NTVtypes of NTVsingle are identical - the NTVvalue are structurally identical: o if the NTVvalue is a list of NTV entities, each NTV entity has to be structurally identical o if the NTVvalue is a JSONvalue, the JSONvalues have to be identical _Example of structural equality (JsonNTV representation):_ _{"::int32": [10, 20] } and [{":int32": 10}, {":int32": 20}]_ *Semantic equality:* Two NTV entities are semantically equals if : - the NTVname are identical - the NTVvalue are semantically identical: THOMY Expires 28 November 2024 [Page 21] Internet-Draft JSON semantic format (JSON-NTV) May 2024 o if the NTVvalue is a list of NTV entities, each NTV entity has to be semantically identical o if the NTVvalue is a JSONvalue, the native entity associated to the JSONvalue have to be identical _Example of semantic equality (JsonNTV representation):_ _{":datetime": "2011-11-04T10:05:23+00:00" } and {":datetime": "2011-11-04T11:05:23+01:00"}_ 6.4. NTV Canonical The NTVtype of the NTVlist entities is only useful for constructing the JSON representation (two NTVlists with two different NTVtypes are equal according to the structural equality criteria). A canonical (single) format is chosen to facilitate sharing and analysis of NTV and JsonNTV data. It is defined by setting a value for the NTVtype of an NTVlist entity. The rule is as follows: REQ10: NTVtype is empty, if an included entity is an NTVlist with an empty NTVtype, NTVtype is empty, if all included entities have an NTVtype 'json', NTVtype is the common Namespace, if the common Namespace is not the GlobalNamespace, In other cases, the NTVtype is the same as that of the first included entity. This rule is simple to implement and allows you to have a compact JsonNTV format (another more complex choice would have been to take the most frequent NTVtype among the included entities). 6.5. JSON as a subtype of NTV The Appendix C shows that there is an equivalence between Json entities (JsonArray, JsonObject, JsonNumber, JsonString, JsonFalse, JsonTrue or JsonNull) and the corresponding NTV entities called JNTV (resp. NTVarray, NTVobject, NTVnumber, NTVstring, NTVfalse, NTVtrue , NTVnull). JNTV entities have several properties: THOMY Expires 28 November 2024 [Page 22] Internet-Draft JSON semantic format (JSON-NTV) May 2024 * JNTV and JSON structures are substitutable with respect to functions associated with Json structures (e.g. generation of the JsonText format), * Strict equality or Structural equality between two JNTV entities are equivalent to equality between JsonNTV representations * JNTV are canonical NTV entity * NTV Pointer of JNTV are identical to Json Pointer of JsonNTV representations 6.6. extended NTV structure The NTVvalue of NTV entities are JsonValue. In the extended NTV structure, NTVvalue can be every kind of data. With this structure, the NTV representation is a "json like" data where: * JsonNTVvalue is always NTVvalue, * JsonNTVtype is optional (if NTVtype can be deduced from the NTVvalue), * JsonNTVname is optional (if NTVname can be deduced from the NTVvalue). _Examples of extended NTV representation:_ _{ "python date" : [ datetime.date(2022, 1, 18), datetime.date(2023, 1, 12) ] }_ _this "json like" structure can be converted in JsonNTV format:_ _{ "python date::date" : [ "2022-01-18", "2023-01-12" ] }_ 6.7. nested NTVsingle entities As defined in Section 2.2.1 an entity with Json representation can be taken into account. Appendix A defines usual NTVtypes (e.g. date, coordinate, email) but also NTVtypes associated to structured data (e.g. dataset, NTV data, custom format): The example in Figure 7 is the representation of a NTVlist with three NTVsingle: THOMY Expires 28 November 2024 [Page 23] Internet-Draft JSON semantic format (JSON-NTV) May 2024 * "dataset" is a NTVsingle build with a 'tab' structure (NTVdataset defined in [NTV-TAB]). This NTVdataset includes in 'field2' an NTV structure, * "ntvdata" is a NTVsingle build with a 'ntv' structure. This structure includes an other NTV structure, * "sensor" is a NTVsingle build with a custom structure. This structure includes a NTVdataset. ex_list = { "structure": { "dataset:tab":{ "field1": [1,2,3], "field2": [4,5,{":ntv": {"min": 6, "max": 7}] }, "ntvdata:ntv":{ "equinox:date": "2024-03-20", "paris:point": [2.35, 48.85], "other data:ntv": {"val1": 1, "val2": 2} }, "sensor:$sensor": [ 8.51, 3.5, 4.2, {":tab": [[1,2,3,4], [5,6,7,8]]} ] } } Figure 7: Nested NTVsingle Nested NTVsingle is treated as simple NTVsingle and can be used with extended NTV structures. 7. IANA Considerations No IANA actions are required : Any JsonValue is a JsonNTVValue and conversely, any JsonNTVvalue is a JsonValue. Thus, any JSON data may or may not be treated as JsonNTV data, so there is no need to create a specific MIME media type for JsonNTV. All properties of the MIME media type "application/json" are applicable. THOMY Expires 28 November 2024 [Page 24] Internet-Draft JSON semantic format (JSON-NTV) May 2024 8. Security Considerations The format used for NTV data exchanges is the JSON format. So, all the security considerations of [RFC8259] apply. The NTV structure provides no cryptographic integrity protection of any kind. 9. References 9.1. Normative References [RFC4648] Josefsson, S., "The Base16, Base32, and Base64 Data Encodings", RFC 4648, DOI 10.17487/RFC4648, October 2006, . [RFC7946] Butler, H., Daly, M., Doyle, A., Gillies, S., Hagen, S., and T. Schaub, "The GeoJSON Format", RFC 7946, DOI 10.17487/RFC7946, August 2016, . [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . [RFC5234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax Specifications: ABNF", STD 68, RFC 5234, DOI 10.17487/RFC5234, January 2008, . [RFC6901] Bryan, P., Ed., Zyp, K., and M. Nottingham, Ed., "JavaScript Object Notation (JSON) Pointer", RFC 6901, DOI 10.17487/RFC6901, April 2013, . [RFC8259] Bray, T., Ed., "The JavaScript Object Notation (JSON) Data Interchange Format", STD 90, RFC 8259, DOI 10.17487/RFC8259, December 2017, . [RFC3339] Klyne, G. and C. Newman, "Date and Time on the Internet: Timestamps", RFC 3339, DOI 10.17487/RFC3339, July 2002, . THOMY Expires 28 November 2024 [Page 25] Internet-Draft JSON semantic format (JSON-NTV) May 2024 [RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language", RFC 7950, DOI 10.17487/RFC7950, August 2016, . 9.2. Informative References [DFS] "Wikipedia", "Depth-first search algorithm", . [NTV-TAB] Thomy, P., "NTV tabular format (NTV-TAB)", 2023, . [JSON-ND] Kleidon, G., "JSON-ND", 2020, . [JSON-NTV] Thomy, P., "JSON-NTV", 2022, . [OLC] "Google", "Open Location Code", 2016, . [W3C_TAB] "W3C", "Recommendation : Model for Tabular Data and Metadata on the Web", 17 December 2015, . [ISO_3166-1_alpha-2] "ISO", "Codes for the representation of names of countries and their subdivisions - Part 1: Country code", 2020, . [TABLE_SCHEMA] "Frictionless", "Table Schema specification", 5 October 2021, . [JSON_SCHEMA] "JSON Schema", "JSON Schema validation", 16 June 2022, . Appendix A. Global DataType and Namespace The structure of DataType by Namespace makes it possible to have DataType or Namespace corresponding to recognized standards at the global level. THOMY Expires 28 November 2024 [Page 26] Internet-Draft JSON semantic format (JSON-NTV) May 2024 A standard DataType / Namespace is a DataType / Namespace defined in the Global Namespace. The standard DataType and Namespace are listed below. A.1. Json Json DataType have a generic DataType : "json" +========================+=======================+==================+ | DataTypeName (generic) | NTVvalue | example NTVvalue | +========================+=======================+==================+ | json | generic DataType | | +------------------------+-----------------------+------------------+ | number (json) | JsonNumber [RFC8259] | 10 | +------------------------+-----------------------+------------------+ | boolean (json) | JsonBoolean | "true" | | | [RFC8259] | | +------------------------+-----------------------+------------------+ | null (json) | JsonNull [RFC8259] | "null" | +------------------------+-----------------------+------------------+ | string (json) | JsonString [RFC8259] | "value" | +------------------------+-----------------------+------------------+ | array (json) | JsonArray [RFC8259] | [1.1, 2.2] | +------------------------+-----------------------+------------------+ | object (json) | JsonObject [RFC8259] | {"value1": 1, | | | | "value2": 2} | +------------------------+-----------------------+------------------+ Table 3: Json DataType A.2. Numbers +===========================+======================+================+ | DataTypeName | NTVvalue | comment | +===========================+======================+================+ | int | JsonNumber [RFC8259] | integer | +---------------------------+----------------------+----------------+ | int8, int16, | JsonNumber [RFC8259] | signed integer | | int32, int64 | | | +---------------------------+----------------------+----------------+ | uint8, uint16, | JsonNumber [RFC8259] | unsigned | | uint32, uint64 | | integer | +---------------------------+----------------------+----------------+ | decimal64 | JsonNumber [RFC8259] | decimal | | | | floating point | +---------------------------+----------------------+----------------+ | float | JsonNumber [RFC8259] | binary | THOMY Expires 28 November 2024 [Page 27] Internet-Draft JSON semantic format (JSON-NTV) May 2024 | | | floating point | +---------------------------+----------------------+----------------+ | float16, | JsonNumber [RFC8259] | binary | | float32, float64 | | floating point | +---------------------------+----------------------+----------------+ Table 4: Numbers DataType A.3. Binary encoding +==============+===========================+========================+ | DataTypeName | NTVvalue | comment | +==============+===========================+========================+ | bit | binary digit | string "0" or "1" | +--------------+---------------------------+------------------------+ | binary | bit string | string of bit array | +--------------+---------------------------+------------------------+ | base16 | base16 encoding | string of hexadecimal | | | [RFC4648] | array | +--------------+---------------------------+------------------------+ | base32 | base32 encoding | string of | | | [RFC4648] | duotrigesimal array | +--------------+---------------------------+------------------------+ | base64 | base64 encoding | string of | | | [RFC4648] | tetrasexagesimal array | +--------------+---------------------------+------------------------+ Table 5: Binary DataType A.4. Datation Datation DataType have a generic DataType : "dat" THOMY Expires 28 November 2024 [Page 28] Internet-Draft JSON semantic format (JSON-NTV) May 2024 +============+========================+============================+ |DataTypeName|NTVvalue | example NTVvalue | |(generic) | | | +============+========================+============================+ |year |fullyear [RFC3339] | 1998 | +------------+------------------------+----------------------------+ |month |month [RFC3339] | 10 | +------------+------------------------+----------------------------+ |yearmonth |year + month (ISO8601-1)| 1998-10 | +------------+------------------------+----------------------------+ |day |mday [RFC3339] day of | 21 | | |month | | +------------+------------------------+----------------------------+ |wday |wday [RFC3339] day of | 7 | | |week | | +------------+------------------------+----------------------------+ |yday |yday [RFC3339] day of | 360 | | |year | | +------------+------------------------+----------------------------+ |week |week [RFC3339] | 38 | +------------+------------------------+----------------------------+ |hour |hour [RFC3339] | 20 | +------------+------------------------+----------------------------+ |minute |minute [RFC3339] | 18 | +------------+------------------------+----------------------------+ |second |second [RFC3339] | 54 | +------------+------------------------+----------------------------+ |dat |generic DataType | | +------------+------------------------+----------------------------+ |date (dat) |date [RFC3339] | "2022-01-28"" | +------------+------------------------+----------------------------+ |time (dat) |timespec-base [time- | "T18:23:54", "18:23", | | |fraction][RFC3339] | "T18" | +------------+------------------------+----------------------------+ |timetz (dat)|timespec-base [time- | "T18:23:54+0400" | | |fraction] time- | | | |zone[RFC3339] | | +------------+------------------------+----------------------------+ |datetime |iso-date-time (without | "2022-01-28T18-23-54" | |(dat) |time-zone)[RFC3339] | | +------------+------------------------+----------------------------+ |datetimetz |iso-date-time (with | "2022-01-28T18-23-54+0400" | |(dat) |time-zone)[RFC3339] | | +------------+------------------------+----------------------------+ Table 6: Datation DataType THOMY Expires 28 November 2024 [Page 29] Internet-Draft JSON semantic format (JSON-NTV) May 2024 A.5. Period and Duration +==============+===========+======================================+ | DataTypeName | NTVvalue | example NTVvalue | +==============+===========+======================================+ | duration | duration | "P3Y6M4DT12H30M5S" | | | [RFC3339] | | +--------------+-----------+--------------------------------------+ | timearray | JsonArray | [dat1, dat2] | | | | | | | | _dat1, dat2 have "dat" DataTypeName_ | +--------------+-----------+--------------------------------------+ | period | period | "2022-01-01 / 2022-01-30" | | | [RFC3339] | | | | | "2022-01-01 / P3Y6M4DT12H30M5S" | +--------------+-----------+--------------------------------------+ Table 7: Period and Duration DataType A.6. Location Location DataType have a generic DataType : "loc". The CRS (Coordinate Reference Systems) is geographic, using the World Geodetic System 1984 (WGS 84) datum, with longitude and latitude units of decimal degrees (EPSG:4326). +===============+=================+=================================+ | DataTypeName | NTVvalue | example NTVvalue | | (generic) | | | +===============+=================+=================================+ | loc | generic | | | | DataType | | +---------------+-----------------+---------------------------------+ | point (loc) | Point | [ 5.12, 45.256 ] _(lon, | | | coordinates | lat)_ | | | [RFC7946] | | +---------------+-----------------+---------------------------------+ | pointstr | Point | "5.12, 45.256" _(lon, | | (loc) | coordinates | lat)_ | | | (string) | | +---------------+-----------------+---------------------------------+ | pointobj | Point | {"lon": 5.12, "lat": | | (loc) | coordinates | 45.256} | | | (object) | | +---------------+-----------------+---------------------------------+ | multipoint | MultiPoint | [pt1, pt2, pt3] | | | coordinates | | THOMY Expires 28 November 2024 [Page 30] Internet-Draft JSON semantic format (JSON-NTV) May 2024 | | [RFC7946] | _ptx is "point" NTVvalue_ | +---------------+-----------------+---------------------------------+ | line (loc) | LineString | [pt1, pt2, pt3] | | | coordinates | | | | [RFC7946] | _ptx is "point" NTVvalue_ | +---------------+-----------------+---------------------------------+ | multiline | MultiLineString | [li1, li2, li3] | | | coordinates | | | | [RFC7946] | _lix is "line" NTVvalue_ | +---------------+-----------------+---------------------------------+ | polygon (loc) | Polygon | [rg1, rg2, rg3] | | | coordinates | | | | [RFC7946] | _rgx is "line" NTVvalue | | | | (ring)_ | +---------------+-----------------+---------------------------------+ | multipolygon | MultiPolygon | [pl1, pl2, pl3] | | (loc) | coordinates | | | | [RFC7946] | _plx is "polygon" | | | | NTVvalue_ | +---------------+-----------------+---------------------------------+ | geometry | Geometry | "point", "line" or | | | coordinates | "polygon" | | | [RFC7946] | | | | | NTVvalue | +---------------+-----------------+---------------------------------+ | multigeometry | MultiGeometry | [geo1, geo2, geo3] | | | coordinates | | | | [RFC7946] | _geox is "geometry" | | | | NTVvalue_ | +---------------+-----------------+---------------------------------+ | box (loc) | box coordinates | [ -10.0, -10.0, 10.0, | | | [RFC7946] | 10.0 ] | +---------------+-----------------+---------------------------------+ | geojson (loc) | geoJSON object | {"type": "point", | | | [RFC7946] | "coordinates": [40.0, | | | | 0.0]} | +---------------+-----------------+---------------------------------+ | codeolc (loc) | Open Location | "8FW4V75V+8F6" | | | Code [OLC] | | +---------------+-----------------+---------------------------------+ Table 8: Location DataType THOMY Expires 28 November 2024 [Page 31] Internet-Draft JSON semantic format (JSON-NTV) May 2024 A.7. Structured data +==============+=============================================+ | DataTypeName | NTVvalue | +==============+=============================================+ | row | row [W3C_TAB] | +--------------+---------------------------------------------+ | field | column [W3C_TAB] | +--------------+---------------------------------------------+ | tab | table [NTV-TAB] | +--------------+---------------------------------------------+ | ndarray | multidimensional array [NTV-TAB] | +--------------+---------------------------------------------+ | xndarray | labelled multidimensional array[NTV-TAB] | +--------------+---------------------------------------------+ | xdataset | coordinated multidimensional array[NTV-TAB] | +--------------+---------------------------------------------+ | ntv | JsonNTV | +--------------+---------------------------------------------+ | sch | Schema | +--------------+---------------------------------------------+ Table 9: Structured DataType The data structure associated to this DataTypeName are defined in specific document. A.8. Normalized String +============+=================+===================================+ |DataTypeName|NTVvalue | example NTVvalue | +============+=================+===================================+ |unit |Physical | "kg / s2" | | |quantities | | +------------+-----------------+-----------------------------------+ |uri |URI (RFC3986) | "https://www.ietf.org/rfc/ | | | | rfc3986.txt" | | | | | | | | "geo:13.4125,103.86673" (RFC5870) | | | | | | | | "info:eu-repo/dai/nl/12345" | | | | | | | | "mailto:John.Doe@example.com" | | | | | | | | "tel:+1-201-555-0123" (RFC3966) | +------------+-----------------+-----------------------------------+ |uriref |URI-reference | "www.example.com/questions/3456/ | | |(RFC3986) | my-document" | THOMY Expires 28 November 2024 [Page 32] Internet-Draft JSON semantic format (JSON-NTV) May 2024 +------------+-----------------+-----------------------------------+ |iri |internationalized| "http://www.example.org/D%FCrst" | | |URI (RFC3987) | | +------------+-----------------+-----------------------------------+ |iriref |IRI-reference | "www.example.org/D%FCrst" | | |(RFC3987) | | +------------+-----------------+-----------------------------------+ |uritem |URI-template | "{+x,hello,y}" | | |(RFC6570) | | +------------+-----------------+-----------------------------------+ |uuid |UUID (RFC4122) | "f81d4fae-7dec- | | | | 11d0-a765-00a0c91e6bf6" | +------------+-----------------+-----------------------------------+ |email |address (RFC5322)| "John Doe " | +------------+-----------------+-----------------------------------+ |idnemail |internationalized| | | |adress (RFC6531) | | +------------+-----------------+-----------------------------------+ |hostname |Host Names | "en.wikipedia.org" | | |(RFC1123) | | +------------+-----------------+-----------------------------------+ |idnhostname |internationalized| | | |Host Names | | | |(RFC5890) | | +------------+-----------------+-----------------------------------+ |jpointer |JSON pointer | "/foo/0" | | |(RFC6901) | | +------------+-----------------+-----------------------------------+ |rjpointer |relative JSON | "1/nested/objects" | | |pointer (I-D) | | +------------+-----------------+-----------------------------------+ |regex |regular | "[Ss]mith\\\\b" | | |expression (ECMA | | | |262) | | +------------+-----------------+-----------------------------------+ |ipv4 |IPv4 address | "192.168.1.1" | | |(RFC2673) | | +------------+-----------------+-----------------------------------+ |ipv6 |IPv6 address | "2001:0db8:85a3:0000:00 | | |(RFC2373) | | | | | 00:8a2e:0370:7334" | +------------+-----------------+-----------------------------------+ |file |file-hier-part | "///path/to/file" | | |(RFC8089) | | | | | "//host.example.com/path/to/file" | +------------+-----------------+-----------------------------------+ Table 10: Structured DataType THOMY Expires 28 November 2024 [Page 33] Internet-Draft JSON semantic format (JSON-NTV) May 2024 Keywords are not defined as Normalized String (eg. "id", "mandatory", "units"), they can be used as custom DataType (eg. "$id", "$mandatory", "$units") A.9. Namespace The global Namespace includes Namespaces for countries, dependent territories and special areas as defined in [ISO_3166-1_alpha-2] The JsonNamespace for those Namespace is composed by the two digits of the country following by a dot. _Example :_ _"fr." is the France JsonNamespace_ _"un." is The United Nations JsonNamespace_ Each Namespace defines a list of included DataType and Namespace. A.10. Custom DataType and Namespace Custom DataType and Namespace can be created in any Namespace. Table 11 below presents some examples of custom DataType. THOMY Expires 28 November 2024 [Page 34] Internet-Draft JSON semantic format (JSON-NTV) May 2024 +================+=========================================+ | JsonDataType | comment or JsonNTV example | +================+=========================================+ | "$id" | defined in the global Namespace | | | | | | eg. { ":$id": 5426849" } | +----------------+-----------------------------------------+ | "$iata" | IATA airport code | | | | | | eg. {"Paris Nord:$iata": "CDG"} | +----------------+-----------------------------------------+ | "$uic.station" | UIC station code | | | | | | eg. {"Nantes station:$uic.station" : | | | "8748100"} | +----------------+-----------------------------------------+ | "fr.$city" | DataType "city" in "fr." Namespace | | | | | | eg. {":fr.$city" : "Paris"} | +----------------+-----------------------------------------+ | "$schemaorg." | "schemaorg" catalog | | | | | | eg. { ":$schemaorg.propertyID": "NO2" } | | | | | | { ":$schemaorg.unitText": "mg/m3"} | +----------------+-----------------------------------------+ | "$darwincore." | "darwincore" catalog | | | | | | eg. { ":$darwincore.acceptedNameUsage": | | | "Tamias minimus" } | +----------------+-----------------------------------------+ Table 11: Examples of custom DataType Appendix B. Complete ABNF notation ; representation of DataType and Namespace (Name and LongName) DataTypeLongName = NamespaceParentLongName DataTypeName NamespaceLongName = NamespaceParentLongName NamespaceName NamespaceParentLongName = NamespaceLongName NamespaceName = [ ["$"] JsonString "." ] ; REQ2 REQ3 DataTypeName = TypeBaseName ["[" TypeExtensionName "]"] TypeBaseName = ["$"] JsonString ; REQ3 TypeExtensionName = JsonString THOMY Expires 28 November 2024 [Page 35] Internet-Draft JSON semantic format (JSON-NTV) May 2024 ; JSON representation of NTV entities (JsonNTV) JsonNTV = JsonNTVnamed / JsonNTVsimple ; REQ4 JsonNTVnamed = beginObject JsonNTVMember endObject JsonNTVsimple = JsonNTVvalue JsonNTVMember = JsonNTVname nSep JsonNTVvalue ; Extract of JSON grammar used in this document beginArray = ws "[" ws beginObject = ws "{" ws endArray = ws "]" ws endObject = ws "}" ws nSep = ws ":" ws vSep = ws "," ws ws = *( %x20 / %x09 / %x0A / %x0D ) JsonValue = JsonValue ; indicates that rule is defined in RFC8259 JsonString = JsonString ; indicates that rule is defined in RFC8259 ; JSON representation of NTVname and NTVtype (JsonNTVname) JsonNTVname = NTVname JsonSepType JsonSepType = [singleSep [JsonNTVtype]]/([listSep] JsonNTVtype) ; REQ5 REQ6 NTVname = JsonString singleSep = ":" ; NTVsingle separator listSep = "::" ; NTVlist separator ; JSON representation of NTVType (JsonNTVtype) JsonNTVtype = [ NTVtypeLongName / NTVtypeRelativeName ] ; REQ7 NTVtypeLongName = DataTypeLongName / NamespaceLongName NTVtypeRelativeName = *NamespaceName (DataTypeName / NamespaceName) ; REQ7 ; JSON representation of NTVvalue (JsonNTVvalue) JsonNTVvalue = JsonNTVsingleValue / JsonNTVlistValue JsonNTVsingleValue = NTVsingleValue JsonNTVlistValue = JsonNTVarrayValue / JsonNTVobjectValue THOMY Expires 28 November 2024 [Page 36] Internet-Draft JSON semantic format (JSON-NTV) May 2024 ; REQ8 REQ9 JsonNTVarrayValue = beginArray ListJsonNTVvalue endArray ListJsonNTVvalue = [JsonNTV *( vSep JsonNTV )] JsonNTVobjectValue = beginObject ListJsonNTVmember endObject ListJsonNTVmember = [JsonNTVMember *( vSep JsonNTVMember)] NTVsingleValue = JsonValue Figure 8: Collected ABNF grammar Appendix C. JSON-NTV equivalence This Appendix shows that we can associate with each JsonValue an NTV entity whose JSON representation (JsonNtv) is identical to the JsonValue. To do this, let's call NTVarray, NTVobject, NTVnumber, NTVstring, NTVfalse, NTVtrue, NTVnull the entities defined below. * Json primitives An NTVprimitive entity (resp. NTVnumber, NTVstring, NTVfalse, NTVtrue or NTVnull) is a Vsingle entity whose NTVvalue is a JsonPrimitive (resp. JsonNumber, JsonString, JsonFalse, JsonTrue or JsonNull). For example, the NTVstring entity associated with the JsonString "foo" has the following attributes: o NTVname: empty, o NTVtype: "json", o NTVvalue: "foo". Given the NTV rules, the JsonNtv is equal to the NTVvalue and therefore the JsonPrimitive. Conversely, an NTV parser converts a JsonPrimitive into the corresponding NTVprimitive. * Json Array The NTVarray entity is the Vlist entity composed of the NTV entities associated with the JsonElements of the JsonArray. For example, for a JsonArray composed of the JsonNumber represented by 25 and the JsonArray represented by [1,2], the NTVarray has the following attributes: THOMY Expires 28 November 2024 [Page 37] Internet-Draft JSON semantic format (JSON-NTV) May 2024 o NTVname: None o NTVtype: None o NTVvalue: composed of NTVnumber 25 and the NTVarray corresponding to the JsonArray [1,2] As before, taking into account the NTV rules, the JsonNtv is equal to the json representation of the NTVvalue which is identical to the JsonArray. Conversely, an NTV parser converts a JsonArray into the corresponding NTVarray. * JsonObject Let's call NTVmember the NTV entity associated with the JsonObject corresponding to a JsonMember (key/val). This JsonObject has the representation {key: val}. If val is a Json Primitive, NTVmember is an NVsingle: o NTVname:key o NTVtype: "json" o NTVvalue: val If val is a JsonArray or JsonObject, NTVmember is an NVlist: o NTVname:key o NTVtype: None o NTVvalue: composed of NTV entities associated with the elements of the JsonArray (or members of the JsonObject) The NTVobject entity is the Vlist entity composed of the NTVmember entities associated with the JsonMembers of the JsonObject. For example, for a JsonObject composed of the JsonMember represented by "foo": 25 and the JsonMember represented by "bar": [1,2], the NTVObject will be: o NTVname: None o NTVtype: None THOMY Expires 28 November 2024 [Page 38] Internet-Draft JSON semantic format (JSON-NTV) May 2024 o NTVvalue: composed of NVsingle (NTVname: "foo", NTVtype: "json", NTVvalue: 25) and NVlist (NTVname: "bar", NTVtype: None, NTVvalue: composed of NTVnumber 1 and NTVnumber 2). Similarly to the JsonArray, given the NTV rules, the JsonNtv is equal to the json representation of the NTVvalue which is identical to the JsonObject. Conversely, an NTV parser converts a JsonObject into the corresponding NTVObject. Thus, for all Json entities, we have an equivalence with an NTV entity Appendix D. Mapping DataTypes This Appendix presents the mapping between DataTypes and the types defined in Data schemas or Data languages. D.1. Table-Schema The mapping concerns Table Schema types and formats [TABLE_SCHEMA]. Parsable and pattern formats (datation) and topojson (location) are not included +===========+====================================+==============+ | type | format | DataType | +===========+====================================+==============+ | string | default | string | +-----------+------------------------------------+--------------+ | string | email | email | +-----------+------------------------------------+--------------+ | string | uri | uri | +-----------+------------------------------------+--------------+ | string | binary (base64 string) | base64 | +-----------+------------------------------------+--------------+ | string | uuid | uuid | +-----------+------------------------------------+--------------+ | number | default | number | +-----------+------------------------------------+--------------+ | integer | default | int | +-----------+------------------------------------+--------------+ | boolean | default | boolean | +-----------+------------------------------------+--------------+ | object | default (json) | json | +-----------+------------------------------------+--------------+ | array | default (json array) | array | +-----------+------------------------------------+--------------+ THOMY Expires 28 November 2024 [Page 39] Internet-Draft JSON semantic format (JSON-NTV) May 2024 | date | default (date ISO8601) | date | +-----------+------------------------------------+--------------+ | time | default (time ISO8601) | time | +-----------+------------------------------------+--------------+ | datetime | default (datetime ISO8601 in UTC) | datetime | +-----------+------------------------------------+--------------+ | year | default | year | +-----------+------------------------------------+--------------+ | yearmonth | default | yearmonth | +-----------+------------------------------------+--------------+ | duration | default (lexical duration ISO8601) | duration | +-----------+------------------------------------+--------------+ | geopoint | default (string "lon, lat") | pointstr | +-----------+------------------------------------+--------------+ | geopoint | array (array [lon, lat]) | point | +-----------+------------------------------------+--------------+ | geopoint | object (eg {"lon": 90, "lat": 45}) | pointobj | +-----------+------------------------------------+--------------+ | geojson | default (geojson spec) | geojson | +-----------+------------------------------------+--------------+ | -any- | -any- | $xxx (custom | | | | type) | +-----------+------------------------------------+--------------+ Table 12: Table-Schema types D.2. JSON Schema The mapping concerns JSON-schema [JSON_SCHEMA] primitive types, defined formats and String-Encoded data . +=================+=======================+=============+ | type | format | DataType | +=================+=======================+=============+ | string | | string | +-----------------+-----------------------+-------------+ | string | date-time | datetime | +-----------------+-----------------------+-------------+ | string | time | time | +-----------------+-----------------------+-------------+ | string | date | date | +-----------------+-----------------------+-------------+ | string | duration | duration | +-----------------+-----------------------+-------------+ | string | email | email | +-----------------+-----------------------+-------------+ | string | idn-email | idnemail | +-----------------+-----------------------+-------------+ THOMY Expires 28 November 2024 [Page 40] Internet-Draft JSON semantic format (JSON-NTV) May 2024 | string | hostname | hostname | +-----------------+-----------------------+-------------+ | string | idn-hostname | idnhostname | +-----------------+-----------------------+-------------+ | string | ipv4 | ipv4 | +-----------------+-----------------------+-------------+ | string | ipv6 | ipv6 | +-----------------+-----------------------+-------------+ | string | uuid | uuid | +-----------------+-----------------------+-------------+ | string | uri | uri | +-----------------+-----------------------+-------------+ | string | uri-reference | uriref | +-----------------+-----------------------+-------------+ | string | uri-template | uritem | +-----------------+-----------------------+-------------+ | string | iri | iri | +-----------------+-----------------------+-------------+ | string | iri-reference | iriref | +-----------------+-----------------------+-------------+ | string | json-pointer | jpointer | +-----------------+-----------------------+-------------+ | string | relative-json-pointer | rjpointer | +-----------------+-----------------------+-------------+ | string | regex | regex | +-----------------+-----------------------+-------------+ | number | | number | +-----------------+-----------------------+-------------+ | integer | | int | +-----------------+-----------------------+-------------+ | boolean | | boolean | +-----------------+-----------------------+-------------+ | object | | object | +-----------------+-----------------------+-------------+ | array | | array | +-----------------+-----------------------+-------------+ | contentEncoding | base64 | base64 | +-----------------+-----------------------+-------------+ | contentEncoding | base32 | base32 | +-----------------+-----------------------+-------------+ | contentEncoding | base16 | base16 | +-----------------+-----------------------+-------------+ | contentEncoding | binary | binary | +-----------------+-----------------------+-------------+ | null | | null | +-----------------+-----------------------+-------------+ Table 13: JSON Schema types THOMY Expires 28 November 2024 [Page 41] Internet-Draft JSON semantic format (JSON-NTV) May 2024 D.3. YANG The mapping concerns YANG [RFC7950] build-in types defined. Enumeration, leafref, identityref, instance-identifier, union are not included. +===========+===========+==========+ | type | DataType | comments | +===========+===========+==========+ | boolean | boolean | | +-----------+-----------+----------+ | decimal64 | decimal64 | | +-----------+-----------+----------+ | empty | null | | +-----------+-----------+----------+ | int8 | int8 | | +-----------+-----------+----------+ | int16 | int16 | | +-----------+-----------+----------+ | int32 | int32 | | +-----------+-----------+----------+ | int64 | int64 | | +-----------+-----------+----------+ | uint8 | uint8 | | +-----------+-----------+----------+ | uint16 | uint16 | | +-----------+-----------+----------+ | uint32 | uint32 | | +-----------+-----------+----------+ | uint64 | uint64 | | +-----------+-----------+----------+ | string | string | | +-----------+-----------+----------+ | bit | bit | | +-----------+-----------+----------+ | binary | binary | | +-----------+-----------+----------+ Table 14: YANG types Acknowledgements TBD Contributors TBD THOMY Expires 28 November 2024 [Page 42] Internet-Draft JSON semantic format (JSON-NTV) May 2024 Author's Address Philippe THOMY Loco-labs 476 chemin du gaf de Famian 84 500 BOLLENE France Email: philippe@loco-labs.io URI: https://github.com/loco-philippe/NTV/blob/main/README.md THOMY Expires 28 November 2024 [Page 43]