Knowledge Representation Markup Language

• Knowledge Representation Markup Language
  • Overview
  • Example
    • Input
    • Output
  • Model
    • Logical
    • Physical
  • Quickstart
  • Test

Overview

Knowledge Representation Markup Language (KRML) is a simple language for creating RDF knowledge graphs using Markdown elements: lists of hyperlinks, images, tables and styled or plain text.

As a readable, content-first, low-syntax document format, KRML is optimised for humans. It's intended to facilitate the exchange of structured data between researchers, writers and developers to support the construction of databases of networked information.

The language is defined in this Specification.

Note

KRML is an on-going research project and is not yet ready for use in production.

Example

The following description of the Mona Lisa demonstrates many of the features of the language.

krml examples/mona_lisa.md

Input

mona_lisa.md

---
id: http://example.org/mona-lisa
title: Mona Lisa
language: en
---

- Mona Lisa
  - title
    - > Mona Lisa
    - > La joconde `fr`
    - > la Gioconda `it`
    - > モナ・リザ `jp`
  - a
    - Painting
  - description
    - > Considered an archetypal [masterpiece](https://en.wikipedia.org/wiki/Masterpiece) of the [Italian Renaissance](https://en.wikipedia.org/wiki/Italian_Renaissance), it has been described as "the best known, the most visited, the most written about, the most sung about, [and] the most parodied work of art in the world."
      - source
        - <https://en.wikipedia.org/wiki/Mona_Lisa>
  - image
    - ![Mona Lisa, by Leonardo da Vinci](https://w.wiki/C4dN)
  - creator
    - [Leonardo da Vinci](http://www.wikidata.org/entity/Q762)
      - description
        - > Italian Renaissance polymath (1452−1519)
      - [date of birth](https://schema.org/birthDate)
        - > 1452-04-15 `date`

---
<!-- Term definitions -->

Mona Lisa
: <http://www.wikidata.org/entity/Q12418>
: <https://collections.louvre.fr/ark:/53355/cl010062370>

title
: <https://schema.org/name>

date
: <http://www.w3.org/2001/XMLSchema#date>

Output

{
  "@context": [
    {
      "@version": 1.1,
      "dcmitype": "http://purl.org/dc/dcmitype/",
      "dcterms": "http://purl.org/dc/terms/",
      "owl": "http://www.w3.org/2002/07/owl#",
      "rdf": "http://www.w3.org/1999/02/22-rdf-syntax-ns#",
      "rdfs": "http://www.w3.org/2000/01/rdf-schema#",
      "schema": "https://schema.org/",
      "xsd": "http://www.w3.org/2001/XMLSchema#",
      "_Dataset": {
        "@id": "dcmitype:Dataset"
      },
      "_HTML": {
        "@id": "rdf:HTML"
      },
      "_Image": {
        "@id": "dcmitype:Image"
      },
      "_Table": {
        "@id": "schema:Table"
      },
      "_Text": {
        "@id": "dcmitype:Text"
      },
      "_boolean": {
        "@id": "xsd:boolean"
      },
      "_content": {
        "@id": "rdf:value"
      },
      "_format": {
        "@id": "dcterms:format"
      },
      "_label": {
        "@id": "rdfs:label"
      },
      "_sameAs": {
        "@id": "owl:sameAs",
        "@container": "@set"
      },
      "_seeAlso": {
        "@id": "rdfs:seeAlso",
        "@container": "@set"
      }
    },
    {
      "@base": "http://example.org/",
      "@language": "en",
      "@vocab": "http://example.org/terms/",
      "title": {
        "@id": "https://schema.org/name",
        "@container": "@set"
      },
      "date": {
        "@id": "http://www.w3.org/2001/XMLSchema#date",
        "@type": "@id"
      }
    }
  ],
  "@id": "http://example.org/mona-lisa",
  "@graph": [
    {
      "@id": "http://example.org/mona-lisa",
      "_label": "Mona Lisa"
    },
    {
      "@id": "http://www.wikidata.org/entity/Q12418",
      "_label": "Mona Lisa",
      "@type": [
        "Painting"
      ],
      "title": [
        {
          "@language": "en",
          "@value": "Mona Lisa"
        },
        {
          "@language": "fr",
          "@value": "La joconde"
        },
        {
          "@language": "it",
          "@value": "la Gioconda"
        },
        {
          "@language": "jp",
          "@value": "モナ・リザ"
        }
      ],
      "description": [
        {
          "@type": [
            "_Text"
          ],
          "_content": {
            "@type": "_HTML",
            "@value": "<p lang=\"en\">Considered an archetypal <a href=\"https://en.wikipedia.org/wiki/Masterpiece\">masterpiece</a> of the <a href=\"https://en.wikipedia.org/wiki/Italian_Renaissance\">Italian Renaissance</a>, it has been described as \"the best known, the most visited, the most written about, the most sung about, [and] the most parodied work of art in the world.\"</p>"
          },
          "_seeAlso": [
            {
              "@id": "https://en.wikipedia.org/wiki/Masterpiece",
              "_label": "masterpiece"
            },
            {
              "@id": "https://en.wikipedia.org/wiki/Italian_Renaissance",
              "_label": "Italian Renaissance"
            }
          ],
          "source": [
            {
              "@id": "https://en.wikipedia.org/wiki/Mona_Lisa",
              "_label": "Mona_Lisa"
            }
          ]
        }
      ],
      "image": [
        {
          "@id": "https://w.wiki/C4dN",
          "@type": [
            "_Image"
          ],
          "_label": "Mona Lisa, by Leonardo da Vinci"
        }
      ],
      "creator": [
        {
          "@id": "http://www.wikidata.org/entity/Q762",
          "_label": "Leonardo da Vinci",
          "description": [
            {
              "@language": "en",
              "@value": "Italian Renaissance polymath (1452−1519)"
            }
          ],
          "https://schema.org/birthDate": [
            {
              "@type": "date",
              "@value": "1452-04-15"
            }
          ]
        }
      ]
    },
    {
      "@id": "http://www.wikidata.org/entity/Q12418",
      "_sameAs": [
        {
          "@id": "https://collections.louvre.fr/ark:/53355/cl010062370",
          "_label": "Mona Lisa"
        }
      ]
    }
  ]
}

text/turtle

PREFIX dcmitype: <http://purl.org/dc/dcmitype/>
PREFIX ex: <http://example.org/>
PREFIX exterms: <http://example.org/terms/>
PREFIX owl: <http://www.w3.org/2002/07/owl#>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX schema: <https://schema.org/>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>

ex:mona-lisa
    rdfs:label "Mona Lisa"@en ;
.

<http://www.wikidata.org/entity/Q12418>
    a exterms:Painting ;
    rdfs:label "Mona Lisa"@en ;
    exterms:creator <http://www.wikidata.org/entity/Q762> ;
    exterms:description [
            a dcmitype:Text ;
            exterms:source <https://en.wikipedia.org/wiki/Mona_Lisa> ;
            rdf:value "<p lang=\"en\">Considered an archetypal <a href=\"https://en.wikipedia.org/wiki/Masterpiece\">masterpiece</a> of the <a 
href=\"https://en.wikipedia.org/wiki/Italian_Renaissance\">Italian Renaissance</a>, it has been described as \"the best known, the most visited, the most written about, the most sung about, [and] 
the most parodied work of art in the world.\"</p>"^^rdf:HTML ;
            rdfs:seeAlso
                <https://en.wikipedia.org/wiki/Italian_Renaissance> ,
                <https://en.wikipedia.org/wiki/Masterpiece>
        ] ;
    exterms:image <https://w.wiki/C4dN> ;
    owl:sameAs <https://collections.louvre.fr/ark:/53355/cl010062370> ;
    schema:name
        "Mona Lisa"@en ,
        "La joconde"@fr ,
        "la Gioconda"@it ,
        "モナ・リザ"@jp ;
.

<http://www.wikidata.org/entity/Q762>
    rdfs:label "Leonardo da Vinci"@en ;
    exterms:description "Italian Renaissance polymath (1452−1519)"@en ;
    schema:birthDate "1452-04-15"^^xsd:date ;
.

<https://collections.louvre.fr/ark:/53355/cl010062370>
    rdfs:label "Mona Lisa"@en ;
.

<https://en.wikipedia.org/wiki/Italian_Renaissance>
    rdfs:label "Italian Renaissance"@en ;
.

<https://en.wikipedia.org/wiki/Masterpiece>
    rdfs:label "masterpiece"@en ;
.

<https://en.wikipedia.org/wiki/Mona_Lisa>
    rdfs:label "Mona_Lisa"@en ;
.

<https://w.wiki/C4dN>
    a dcmitype:Image ;
    rdfs:label "Mona Lisa, by Leonardo da Vinci"@en ;
.

application/trig

@prefix dcmitype: <http://purl.org/dc/dcmitype/> .
@prefix ex: <http://example.org/> .
@prefix exterms: <http://example.org/terms/> .
@prefix owl: <http://www.w3.org/2002/07/owl#> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix schema: <https://schema.org/> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .

ex:mona-lisa {
    ex:mona-lisa rdfs:label "Mona Lisa"@en .

    <http://www.wikidata.org/entity/Q12418> a exterms:Painting ;
        rdfs:label "Mona Lisa"@en ;
        exterms:creator <http://www.wikidata.org/entity/Q762> ;
        exterms:description [ a dcmitype:Text ;
                exterms:source <https://en.wikipedia.org/wiki/Mona_Lisa> ;
                rdf:value "<p lang=\"en\">Considered an archetypal <a href=\"https://en.wikipedia.org/wiki/Masterpiece\">masterpiece</a> of the <a 
href=\"https://en.wikipedia.org/wiki/Italian_Renaissance\">Italian Renaissance</a>, it has been described as \"the best known, the most visited, the most written about, the most sung about, [and] 
the most parodied work of art in the world.\"</p>"^^rdf:HTML ;
                rdfs:seeAlso <https://en.wikipedia.org/wiki/Italian_Renaissance>,
                    <https://en.wikipedia.org/wiki/Masterpiece> ] ;
        exterms:image <https://w.wiki/C4dN> ;
        owl:sameAs <https://collections.louvre.fr/ark:/53355/cl010062370> ;
        schema:name "Mona Lisa"@en,
            "La joconde"@fr,
            "la Gioconda"@it,
            "モナ・リザ"@jp .

    <http://www.wikidata.org/entity/Q762> rdfs:label "Leonardo da Vinci"@en ;
        exterms:description "Italian Renaissance polymath (1452−1519)"@en ;
        schema:birthDate "1452-04-15"^^xsd:date .

    <https://collections.louvre.fr/ark:/53355/cl010062370> rdfs:label "Mona Lisa"@en .

    <https://en.wikipedia.org/wiki/Italian_Renaissance> rdfs:label "Italian Renaissance"@en .

    <https://en.wikipedia.org/wiki/Masterpiece> rdfs:label "masterpiece"@en .

    <https://en.wikipedia.org/wiki/Mona_Lisa> rdfs:label "Mona_Lisa"@en .

    <https://w.wiki/C4dN> a dcmitype:Image ;
        rdfs:label "Mona Lisa, by Leonardo da Vinci"@en .
}

Model

Logical

A KRML document is a list of Resources connected to each other via Relationships.

Physical

Documents are composed of nests of ordered or unordered lists of resources, relationships and types.

• Resources are identified by hyperlinks, image links or plain-text
• Relationships are identified by hyperlinks or plain-text
• Texts are blockquotes, with or without styling
• Types are optional qualifiers for human languages or datatypes of Texts as code-fenced text

- Resource
  - relationship
    - Resource
  - relationship
    - > Text `Type`
      - relationship
        - ...

- John
  - knows
    - Paul
  - name
    - > John Winston Lennon `en`

Definition lists can identify any plain text resources, relationships or types.

- John
  - date of birth
    - > 1940-10-09 `date`
  - born in
    - Liverpool
- Paul
  - born in
    - Liverpool

date
: <http://www.w3.org/2001/XMLSchema#>

born in
: <https://schema.org/birthPlace>

Liverpool
: <http://www.wikidata.org/entity/Q24826>

Document configuration parameters can be set in the frontmatter.

---
base: http://www.example.org/
id: http://www/example.org/doc/1
import: file:///path/to/file.md
language: en
title: Lorem Ipsum
vocab: https://schema.org/
---

Quickstart

git clone [email protected]:edwardanderson/krml.git
cd krml
python3 -m venv .venv
source .venv/bin/activate
pip install --editable .

krml /path/to/file.md --help

Test

This project uses pytest with go-testmark fixtures to validate the Specification.