JSON-LD: JSON for Linked Data

JSON-LD: JSON for Linked Data

1. 1. JSON-LDJSON for Linked Data Gregg [email protected] @gkellogg
2. 2. JSON-LDJSON for Linked Data nk ing Li Gregg [email protected] @gkellogg
3. 3. JSONJSON has taken over service APIs
4. 4. Tower of Babel
5. 5. Tower of Babel GitHub{ "type": "User", "followers": 35, "html_url": "https://github.com/gkellogg", "hireable": true, "created_at": "2009-01-13T16:58:46Z", "public_repos": 44, "blog": "http://greggkellogg.net", "bio": "Gregg is a Standards Architect ...", "gravatar_id":"42f948adff3afaa52249d963117af7c8", "following": 35, "company": "Self", "public_gists": 4, "location": "San Rafael, CA", "name": "Gregg Kellogg", "email": "[email protected]", "url": "https://api.github.com/users/gkellogg", "avatar_url": "...", "id": 46296, "login": "gkellogg"
6. 6. Tower of Babel GitHub Twitter {{ "max_id": 195520745634406400, "type": "User", "page": 1, "followers": 35, "query": "%40gkellogg", "html_url": "https://github.com/gkellogg", "results": [{ "hireable": true, "created_at": "Thu, 26 Apr 2012 14:32:33 "created_at": "2009-01-13T16:58:46Z", +0000", "public_repos": 44, "from_user": "kendall", "blog": "http://greggkellogg.net", "from_user_name": "Kendall Clark", "bio": "Gregg is a Standards Architect ...", "id": 195520745634406400, "gravatar_id": "in_reply_to_status_id":"42f948adff3afaa52249d963117af7c8", 195518881811529729, "following": 35, "iso_language_code": "en", "company": "Self", "metadata": {"result_type": "recent"}, "public_gists": 4, "text": "@Gkellogg Multiple resources in a "location": "San Rafael, CA", single JSON-LD struct/doc/message.", "name": "Gregg Kellogg", "to_user": "Gkellogg", "email": "[email protected]", "to_user_id": 6125262, "url": "https://api.github.com/users/gkellogg", "to_user_name": "Gregg Kellogg" "avatar_url": "...", }], "id": 46296, "results_per_page": 1, "login": "gkellogg" "since_id": 0, "since_id_str": "0" }
7. 7. Tower of Babel GitHub Twitter Facebook {{ "max_id": 195520745634406400, { "type": "User", "page": 1, "id": "1236600216", "followers": 35, "query": "%40gkellogg", "name": "Gregg Kellogg", "html_url": "https://github.com/gkellogg", "results": [{ "first_name": "Gregg", "hireable": true, "created_at": "Thu, 26 Apr 2012 14:32:33 "last_name": "Kellogg", "created_at": "2009-01-13T16:58:46Z", +0000", "link": "https://www.facebook.com/ "public_repos": 44, "from_user": "kendall", gkellogg", "blog": "http://greggkellogg.net", "from_user_name": "Kendall Clark", "username": "gkellogg", "bio": "Gregg is a Standards Architect ...", "id": 195520745634406400, "gender": "male", "gravatar_id": "in_reply_to_status_id": "locale": "en_US""42f948adff3afaa52249d963117af7c8", 195518881811529729, } "following": 35, "iso_language_code": "en", "company": "Self", "metadata": {"result_type": "recent"}, "public_gists": 4, "text": "@Gkellogg Multiple resources in a "location": "San Rafael, CA", single JSON-LD struct/doc/message.", "name": "Gregg Kellogg", "to_user": "Gkellogg", "email": "[email protected]", "to_user_id": 6125262, "url": "https://api.github.com/users/gkellogg", "to_user_name": "Gregg Kellogg" "avatar_url": "...", }], "id": 46296, "results_per_page": 1, "login": "gkellogg" "since_id": 0, "since_id_str": "0" }
8. 8. Introducing JSON-LD @graph @context @id JSON-based syntax to express linked data @language @value @list@type @set
9. 9. Self-describing Messages• Give objects types { "@context": { (@type) "schema": "http://schema.org/", "Person": "schema:Person", "colleagues": {"@id": "schema:colleagues", "@type": "@id"}, "name": "schema:name", "image": {"@id": "schema:image", "@type": "@id"}, "url": {"@id": "schema:url", "@type": "@id"} } } { "@context": "http://example.com/context.jsonld", "@type": "Person", "image": "http://localhost:9393/examples/schema.org/janedoe.jpg", "colleagues": [ "http://www.xyz.edu/students/alicejones.html", "http://www.xyz.edu/students/bobsmith.html" ], "name": "Jane Doe", "url": "http://www.janedoe.com" }
10. 10. Self-describing Messages• Give objects types { "@context": { (@type) "schema": "http://schema.org/", "Person": "schema:Person",• "colleagues": {"@id": "schema:colleagues", "@type": "@id"}, Associate properties "name": "schema:name", "image": {"@id": "schema:image", "@type": "@id"}, with IRIs "url": {"@id": "schema:url", "@type": "@id"} } } { "@context": "http://example.com/context.jsonld", "@type": "Person", "image": "http://localhost:9393/examples/schema.org/janedoe.jpg", "colleagues": [ "http://www.xyz.edu/students/alicejones.html", "http://www.xyz.edu/students/bobsmith.html" ], "name": "Jane Doe", "url": "http://www.janedoe.com" }
11. 11. Self-describing Messages• Give objects types { "@context": { (@type) "schema": "http://schema.org/", "Person": "schema:Person",• "colleagues": {"@id": "schema:colleagues", "@type": "@id"}, Associate properties "name": "schema:name", "image": {"@id": "schema:image", "@type": "@id"}, with IRIs "url": {"@id": "schema:url", "@type": "@id"} }• } Use terms defined in a referenced context { "@context": "http://example.com/context.jsonld", "@type": "Person", "image": "http://localhost:9393/examples/schema.org/janedoe.jpg", "colleagues": [ "http://www.xyz.edu/students/alicejones.html", "http://www.xyz.edu/students/bobsmith.html" ], "name": "Jane Doe", "url": "http://www.janedoe.com" }
12. 12. Self-describing Messages• Give objects types { "@context": { (@type) "schema": "http://schema.org/", "Person": "schema:Person",• "colleagues": {"@id": "schema:colleagues", "@type": "@id"}, Associate properties "name": "schema:name", "image": {"@id": "schema:image", "@type": "@id"}, with IRIs "url": {"@id": "schema:url", "@type": "@id"} }• } Use terms defined in a referenced context { "@context": "http://example.com/context.jsonld", "@type": "Person",• Specify property types "image": "http://localhost:9393/examples/schema.org/janedoe.jpg", "knows": [ "http://www.xyz.edu/students/alicejones.html", in context "http://www.xyz.edu/students/bobsmith.html" ], "name": "Jane Doe", "url": "http://www.janedoe.com" }
13. 13. Language Principles
14. 14. • Make full use of JSON syntactic { "@context": "http://json-ld.org/contexts/person", representations "@id": "http://greggkellogg.net/foaf#me", "@type": "Person", • Object defines a subject "name": "Gregg Kellogg", "knows": "http://www.markus-lanthaler.com/" definition }
15. 15. • Make full use of JSON syntactic { "@context": "http://json-ld.org/contexts/person", representations "@id": "http://greggkellogg.net/foaf#me", "@type": "Person", • Object defines a subject "name": "Gregg Kellogg", "knows": "http://www.markus-lanthaler.com/" definition } • Also used for subject reference and value { "@id": "http://greggkellogg.net/foaf#me" } representations
16. 16. • Make full use of JSON syntactic { "@context": "http://json-ld.org/contexts/person", representations "@id": "http://greggkellogg.net/foaf#me", "@type": "Person", • Object defines a subject "name": "Gregg Kellogg", "knows": "http://www.markus-lanthaler.com/" definition } • Also used for subject reference and value { "@id": "http://greggkellogg.net/foaf#me" } representations { "@type": "Recipe", "name": "Moms World Famous Banana Bread", "ingredients": [• Arrays describe sets of unordered values "3 or 4 ripe bananas, smashed", "1 egg", "3/4 cup of sugar" ], • Single values can skip array "nutrition": [{ "@type": ["NutritionInformation"], "calories": ["240 calories"], "fatContent": ["9 grams fat"] }] }
17. 17. • Define terms to use short { "@id": "http://greggkellogg.net/foaf#me", property names "@type": "http://schema.org/Person", "http://schema.org/name": "Gregg Kellogg", • Convenient for JavaScript “.” "http://schema.org/knows": { "@id": "http://www.markus-lanthaler.com/" notation } } { "@context": { "Person": "http://schema.org/Person", "name": "http://schema.org/name", "knows”: "http://schema.org/knows" }, "@id": "http://greggkellogg.net/foaf#me", "@type": "Person", "name": "Gregg Kellogg", "knows": {"@id": "http://www.markus-lanthaler.com/"} }
18. 18. • Define terms to use short { "@id": "http://greggkellogg.net/foaf#me", property names "@type": "http://schema.org/Person", "http://schema.org/name": "Gregg Kellogg", • Convenient for JavaScript “.” "http://schema.org/knows": { "@id": "http://www.markus-lanthaler.com/" notation } }• Add @type coercions to use simple string value. { "@context": { "schema": "http://schema.org/", "Person": "schema:Person", "name": "schema:name", "knows”: { "@id": "schema:knows", "@type": "@id" }, "@id": "http://greggkellogg.net/foaf#me", "@type": "Person", "name": "Gregg Kellogg", "knows": "http://www.markus-lanthaler.com/" }
19. 19. • Define terms to use short { "@id": "http://greggkellogg.net/foaf#me", property names "@type": "http://schema.org/Person", "http://schema.org/name": "Gregg Kellogg", • Convenient for JavaScript “.” "http://schema.org/knows": { "@id": "http://www.markus-lanthaler.com/" notation } }• Add @type coercions to use simple string value. { "@context": { "schema": "http://schema.org/", "Person": "schema:Person",• Use external @context. "name": "schema:name", "knows”: { "@id": "schema:knows", "@type": "@id" } } { "@context": "http://json-ld.org/contexts/person", "@id": "http://greggkellogg.net/foaf#me", "@type": "Person", "name": "Gregg Kellogg", "knows": "http://www.markus-lanthaler.com/" }
20. 20. • { Define referenced subject "@context": "http://json-ld.org/contexts/person", definition with chaining "@id": "http://greggkellogg.net/foaf#me", "@type": "Person", "name": "Gregg Kellogg", "knows": { "@id": "http://www.markus-lanthaler.com/", "@type": "Person", "name": "Markus Lanthaler", "knows" "http://greggkellogg.net/foaf#me" } }
21. 21. • { Define referenced subject "@context": "http://json-ld.org/contexts/person", definition with chaining "@id": "http://greggkellogg.net/foaf#me", "@type": "Person", "name": "Gregg Kellogg", "knows": { "@id": "http://www.markus-lanthaler.com/", "@type": "Person", "name": "Markus Lanthaler", "knows" "http://greggkellogg.net/foaf#me" } } { "@context": "http://json-ld.org/contexts/person", "@id": "http://greggkellogg.net/foaf#me",• Add @language to values. "@type": "Person", "name": "Gregg Kellogg", "honorificSuffix": {"@value": "M.S.", "@language": "en"}, "knows": { "@id": "http://www.markus-lanthaler.com/", "@type": "Person", "name": "Markus Lanthaler", "honorificSuffix": {"@value": "Dipl.Ing.", "@language": "de"}, "knows" "http://greggkellogg.net/foaf#me" } }
22. 22. • Add @type to values. { "@context": "http://json-ld.org/contexts/person", "@id": "http://greggkellogg.net/foaf#me",• Link to externally defined "@type": "Person", "name": "Gregg Kellogg", resources. "birthDate": {"@value": "1957-02-27", "@type": "xsd:date"}, "honorificSuffix": {"@value": "M.S.", "@language": "en"}, "knows": "http://www.markus-lanthaler.com/" }
23. 23. • Add property @type and { "@context": { @language definitions to "schema": "http://schema.org/", context "Person": "schema:Person", "name": "schema:name", "birthDate”: { "@id": "schema: birthDate","@type": "xsd:date" }, "honorificSuffix”: { "@id": "schema:honorificSuffix","@language": "en" }, "knows”: {"@id": "schema:knows","@type": "@id"} }, "@id": "http://greggkellogg.net/foaf#me", "@type": "Person", "name": "Gregg Kellogg", "birthDate": "1957-02-27", "honorificSuffix": "M.S.", "knows": "http://www.markus-lanthaler.com/" }
24. 24. • More features defined in the syntax specification*: • @set, @list, Compact IRIs, Unlabeled Nodes • Embedded @context definitions • Named Graphs* http://json-ld.org/spec/latest/json-ld-syntax
25. 25. Examples “In the Wild”
26. 26. DBpedia { "@graph": [ { "@id": "http://dbpedia.org/resource/DBpedia", "http://dbpedia.org/property/genre" : [ "http://dbpedia.org/resource/Linked_Data" ] }, { "@id": "http://dbpedia.org/resource/Linked_Data", "@type" : [ "http://dbpedia.org/class/yago/Buzzwords" ] , "http://www.w3.org/2002/07/owl#sameAs" : ["http://rdf.freebase.com/ns/m/02r2kb1"] , "http://www.w3.org/2000/01/rdf-schema#comment": [ { "@value" : "Linked Open Data (LOD) bezeichnet ..." , "@language" : "de" } , { "@value" : "In computing, linked Data describes ..." , "@language" : "en" } ], "http://purl.org/dc/terms/subject" : [ "http://dbpedia.org/resource/Category:World_Wide_Web" , "http://dbpedia.org/resource/Category:Buzzwords" , "http://dbpedia.org/resource/Category:Semantic_Web" ], ... }] }http://dbpedia.org/sparql?default-graph-uri=http%3A%2F%2Fdbpedia.org&query=DESCRIBE+<http://dbpedia.org/resource/Linked_Data>&output=application%2Fld%2Bjson
27. 27. Schema.org Using RDFa to JSON-LD bookmarklet* http://linter.structured-data.org/examples/ schema.org/sdo_eg_rdfa_12.html* bookmarklet courtesy of Niklas Lindström
28. 28. Schema.org { "@context": {...}, Using RDFa to JSON-LD bookmarklet* "@graph": [{ "@id": "http://linter.structured-data.org/examples/schema.org/Recipe.rdfa", "rdfa:usesVocabulary": "http://schema.org/" }, { "@type": ["Recipe"], "name": ["Moms World Famous Banana Bread"], "author": ["John Smith"], "publishDate": ["2009-05-08"], "image": [{"@id": ".../bananabread.jpg"}], http://linter.structured-data.org/examples/ "description": ["This classic banana bread recipe ..."], schema.org/sdo_eg_rdfa_12.html "prepTime": ["PT15M"], "cookTime": ["PT1H"], "recipeYield": ["1 loaf"], "nutrition": [{ "@type": ["NutritionInformation"], "calories": ["240 calories"], "fatContent": ["9 grams fat"] }], "ingredients": [ "3 or 4 ripe bananas, smashed", "1 egg", "3/4 cup of sugar" ], "recipeInstructions": ["Preheat the oven to 350 degrees..."], "interactionCount": ["UserComments:140"] }]* bookmarklet courtesy of Niklas Lindström }
29. 29. Drupal http://directory.occupy.net/node/20080.jsonld
30. 30. Drupal { "@context": "http://drupal.example.org/context.jsonld", "@id": "http://directory.occupy.net/occupation/al/occupy- prishtina", "@type": ["ows:Occupation", "schema:Organization"], "foaf:name": "Occupy Prishtina", "schema:name": "Occupy Prishtina", "dc:date": "2012-02-12T21:18:08-05:00", "dc:created": "2012-02-12T21:18:08-05:00", "dc:modified": "2012-02-12T21:57:52-05:00", "sioc:num_replies": 0, "schema:foundingDate": "2011-10-15T00:00:00-04:00", "ows:twitter_account": "@OccupyPrishtina", "foaf:mbox": "", "schema:telephone": "", "foaf:phone": "" } http://directory.occupy.net/node/20080.jsonld
31. 31. PaySwarm { "@context": "http://purl.org/payswarm/v1", "@graph": { "@type": "Transaction", "transfer": { "@type": "Transfer", Named "amount": "7.50", Graph "currency": "USD", "source": "https://bluebank.com/people/manu/accounts/food", "destination": "https://redbank.com/people/gregg/accounts/hosting", "comment": "Chipping in for the Pizza Party tomorrow." }, }, "signature": { "@type": "JsonLdSignature",Signature of "created": "2011-09-23T20:21:34Z", "signer": "http://bluebank.com/people/manu/keys/5", Named "signatureValue": "ExMgoDIyOGQzNGVkM...mOWM32Nj4NTIyZTkZDYMI=" Graph } }
32. 32. Working with data • Expand documents to remove effect of @context.{ "@context": "http://drupal.example.org/context.jsonld", "@id": "http://directory.occupy.net/occupation/al/occupy-prishtina", "@type": ["ows:Occupation", "schema:Organization"], "foaf:name": "Occupy Prishtina", "schema:name": "Occupy Prishtina", "dc:date": "2012-02-12T21:18:08-05:00", "dc:created": "2012-02-12T21:18:08-05:00", "dc:modified": "2012-02-12T21:57:52-05:00", "sioc:num_replies": 0, "schema:foundingDate": "2011-10-15T00:00:00-04:00", "ows:twitter_account": "@OccupyPrishtina", "foaf:mbox": "", "schema:telephone": "", "foaf:phone": ""}
33. 33. Working with data • Expand documents to remove effect of @context. [{ "@id": "http://directory.occupy.net/occupation/al/occupy-prishtina",{ "@type": ["http://vocab.occupy.net/ows#Occupation", "http://schema.org/Organization"], "@context": "http://drupal.example.org/context.jsonld", "http://purl.org/dc/terms/created": [{ "@id": "http://directory.occupy.net/occupation/al/occupy- "@type": "http://www.w3.org/2001/XMLSchema#dateTime", "@value": "2012-02-12T21:18:08-05:00"prishtina", }], "@type": ["ows:Occupation", "schema:Organization"], "http://purl.org/dc/terms/date": [{ "foaf:name": "Occupy Prishtina", "@type": "http://www.w3.org/2001/XMLSchema#dateTime", "schema:name": "Occupy Prishtina", "@value": "2012-02-12T21:18:08-05:00" }], "dc:date": "2012-02-12T21:18:08-05:00", "http://purl.org/dc/terms/modified": [{ "dc:created": "2012-02-12T21:18:08-05:00", "@type": "http://www.w3.org/2001/XMLSchema#dateTime", "dc:modified": "2012-02-12T21:57:52-05:00", "@value": "2012-02-12T21:57:52-05:00" "sioc:num_replies": 0, }], "http://rdfs.org/sioc/ns#num_replies": [{ "schema:foundingDate": "2011-10-15T00:00:00-04:00", "@type": "http://www.w3.org/2001/XMLSchema#integer", "ows:twitter_account": "@OccupyPrishtina", "@value": "0" "foaf:mbox": "", }], "schema:telephone": "", "http://schema.org/foundingDate": [{ "@type": "http://www.w3.org/2001/XMLSchema#date", "foaf:phone": "" "@value": "2011-10-15T00:00:00-04:00"} }], "http://schema.org/name": ["Occupy Prishtina"], "http://schema.org/telephone": [""], "http://vocab.occupy.net/ows#twitter_account": ["@OccupyPrishtina"], "http://xmlns.com/foaf/0.1/mbox": [""], "http://xmlns.com/foaf/0.1/name": ["Occupy Prishtina"], "http://xmlns.com/foaf/0.1/phone": [""] }]
34. 34. Working with data • Compact documents to apply a @context.[{ "@id": "http://directory.occupy.net/occupation/al/occupy-prishtina", "@type": ["http://vocab.occupy.net/ows#Occupation", "http://schema.org/Organization"], "http://purl.org/dc/terms/created": [{ "@type": "http://www.w3.org/2001/XMLSchema#dateTime", "@value": "2012-02-12T21:18:08-05:00" }], "http://purl.org/dc/terms/date": [{ "@type": "http://www.w3.org/2001/XMLSchema#dateTime", "@value": "2012-02-12T21:18:08-05:00" }], "http://purl.org/dc/terms/modified": [{ "@type": "http://www.w3.org/2001/XMLSchema#dateTime", "@value": "2012-02-12T21:57:52-05:00" }], "http://rdfs.org/sioc/ns#num_replies": [{ "@type": "http://www.w3.org/2001/XMLSchema#integer", "@value": "0" }], "http://schema.org/foundingDate": [{ "@type": "http://www.w3.org/2001/XMLSchema#date", "@value": "2011-10-15T00:00:00-04:00" }], "http://schema.org/name": ["Occupy Prishtina"], "http://schema.org/telephone": [""], "http://vocab.occupy.net/ows#twitter_account": ["@OccupyPrishtina"], "http://xmlns.com/foaf/0.1/mbox": [""], "http://xmlns.com/foaf/0.1/name": ["Occupy Prishtina"], "http://xmlns.com/foaf/0.1/phone": [""]}]
35. 35. Working with data • Compact documents to apply a @context.[{ "@id": "http://directory.occupy.net/occupation/al/occupy-prishtina", { "@type": ["http://vocab.occupy.net/ows#Occupation", "http://schema.org/Organization"], "@context": "http://drupal.example.org/context.jsonld", "http://purl.org/dc/terms/created": [{ "@id": "http://directory.occupy.net/occupation/al/occupy- "@type": "http://www.w3.org/2001/XMLSchema#dateTime", prishtina", "@value": "2012-02-12T21:18:08-05:00" "@type": ["ows:Occupation", "schema:Organization"], }], "http://purl.org/dc/terms/date": [{ "foaf:name": "Occupy Prishtina", "@type": "http://www.w3.org/2001/XMLSchema#dateTime", "schema:name": "Occupy Prishtina", "@value": "2012-02-12T21:18:08-05:00" "dc:date": "2012-02-12T21:18:08-05:00", }], "dc:created": "2012-02-12T21:18:08-05:00", "http://purl.org/dc/terms/modified": [{ "@type": "http://www.w3.org/2001/XMLSchema#dateTime", "dc:modified": "2012-02-12T21:57:52-05:00", "@value": "2012-02-12T21:57:52-05:00" "sioc:num_replies": 0, }], "schema:foundingDate": "2011-10-15T00:00:00-04:00", "http://rdfs.org/sioc/ns#num_replies": [{ "ows:twitter_account": "@OccupyPrishtina", "@type": "http://www.w3.org/2001/XMLSchema#integer", "@value": "0" "foaf:mbox": "", }], "schema:telephone": "", "http://schema.org/foundingDate": [{ "foaf:phone": "" "@type": "http://www.w3.org/2001/XMLSchema#date", } "@value": "2011-10-15T00:00:00-04:00" }], "http://schema.org/name": ["Occupy Prishtina"], "http://schema.org/telephone": [""], "http://vocab.occupy.net/ows#twitter_account": ["@OccupyPrishtina"], "http://xmlns.com/foaf/0.1/mbox": [""], "http://xmlns.com/foaf/0.1/name": ["Occupy Prishtina"], "http://xmlns.com/foaf/0.1/phone": [""]}]
36. 36. Working with data • Frame documents to impose structure input{ "@context": { "dc": "http://purl.org/dc/elements/1.1/", "ex": "http://example.org/vocab#", "contains": {"@type": "@id"} }, "@graph": [{ "@id": "http://example.org/test/#library", "@type": "ex:Library", "ex:contains": "http://example.org/test#book" }, { "@id": "http://example.org/test#book", "@type": "ex:Book", "dc:contributor": "Writer", "dc:title": "My Book", "ex:contains": "http://example.org/test#chapter" }, { "@id": "http://example.org/test#chapter", "@type": "ex:Chapter", "dc:description": "Fun", "dc:title": "Chapter One" }]}
37. 37. Working with data • Frame documents to impose structure input frame{ { "@context": { "@context": { "dc": "http://purl.org/dc/elements/1.1/", "dc": "http://purl.org/dc/elements/1.1/", "ex": "http://example.org/vocab#", "ex": "http://example.org/vocab#", "contains": {"@type": "@id"} "contains": {“@id”: “ex:contains”, "@type": "@id", }, “title”: “dc:title” "@graph": [{ }, "@id": "http://example.org/test/#library", "@type": "ex:Library", + "@type": "ex:Library", "contains": { "ex:contains": "http://example.org/test#book" "@type": "ex:Book", }, { "contains": { "@id": "http://example.org/test#book", "@type": "ex:Chapter" "@type": "ex:Book", } "dc:contributor": "Writer", } "dc:title": "My Book", } "ex:contains": "http://example.org/test#chapter" }, { "@id": "http://example.org/test#chapter", "@type": "ex:Chapter", "dc:description": "Fun", "dc:title": "Chapter One" }]}
38. 38. Working with data • Frame documents to impose structure input frame output { {{ "@context": { "@context": { "@context": { "dc": "http://purl.org/dc/elements/1.1/", "dc": "http://purl.org/dc/elements/1.1/", "dc": "http://purl.org/dc/elements/1.1/", "ex": "http://example.org/vocab#", "ex": "http://example.org/vocab#",, "ex": "http://example.org/vocab#", "contains": {“@id”: “ex:contains”, "@type": "@id", "contains": {“@id”: “ex:contains”, "@type": "@id" "contains": {"@type": "@id"} “title”: “dc:title” “title”: “dc:title” }, }, }, "@graph": [{ "@type": "ex:Library", "@graph": [{ "@id": "http://example.org/test/#library", "@id": "http://example.org/test/#library", + "@type": "ex:Library", "contains": { "@type": "ex:Book", "@type": "ex:Library", "ex:contains": "http://example.org/test#book" "contains": { "contains": { }, { "@type": "ex:Chapter" "@id": "http://example.org/test#book", "@id": "http://example.org/test#book", } "@type": "ex:Book", "@type": "ex:Book", } "dc:contributor": "Writer", "dc:contributor": "Writer", } "title": "My Book", "dc:title": "My Book", "contains": { "ex:contains": "http://example.org/test#chapter" "@id": "http://example.org/test#chapter", }, { "@type": "ex:Chapter", "@id": "http://example.org/test#chapter", "dc:description": "Fun", "@type": "ex:Chapter", "title": "Chapter One" "dc:description": "Fun", } "dc:title": "Chapter One" } }] }]} } JavaScript object path: data[‘@graph][0].contains.contains.title
39. 39. Retrofit existing APIsGET /foaf.json HTTP/1.1Host: greggkellogg.netAccept: application/json,*/*;q=0.1====================================HTTP/1.0 200 OK...Content-Type: application/jsonLink: <http://json-ld.org/contexts/person>; rel="describedby"; type="application/ld+json"{ "name": "Gregg Kellogg", "homepage": "http://greggkellogg.net/", "depiction": "http://twitter.com/account/profile_image/gkellogg"}
40. 40. Macros • Transform information { "type": "User", • Add @id to data "followers": 35, "name": "Gregg Kellogg", • Other programmatic transformations "email": "[email protected]", "url": "https://api.github.com/users/ gkellogg", "avatar_url": "...", "id": 46296, "login": "gkellogg" }* json-ld-macros courtesy of Antonio Garrote
41. 41. { Macros "type": "User", "followers": 35, "name": "Gregg Kellogg", "email": "[email protected]", • Transform information "url": "https://api.github.com/users/ gkellogg", "avatar_url": "...", "id": 46296, • Add @id to data } "login": "gkellogg" • Other programmatic transformations* json-ld-macros courtesy of Antonio Garrote
42. 42. { Macros "type": "User", "followers": 35, "name": "Gregg Kellogg", "email": "[email protected]", • Transform information "url": "https://api.github.com/users/ gkellogg", "avatar_url": "...", "id": 46296, • Add @id to data{ } + "login": "gkellogg" • Other programmatic transformations "https://api.github.com/users/*": { "$": { "@context": { "foaf": "http://xmlns.com/foaf/0.1/", "foaf:depiction": {"@type": "@id"}, "gh": "https://api.github.com/vocabulary#" }, "@id": [{"f:valueof": "login"}, {"f:prefix": "http://github.com/"}], "@ns": { "ns:default": "gh", "ns:replace": {"avatar_url": "foaf:depiction", "name":"foaf:name"} }, "@only": ["avatar_url", "name", "followers"], "@type": ["gh:User", "foaf:Person"] } }} * json-ld-macros courtesy of Antonio Garrote
43. 43. { Macros "type": "User", "followers": 35, "name": "Gregg Kellogg", "email": "[email protected]", • Transform information "url": "https://api.github.com/users/ gkellogg", "avatar_url": "...", "id": 46296, • Add @id to data{ } + "login": "gkellogg" • Other programmatic transformations "https://api.github.com/users/*": { "$": { "@context": { { "foaf": "http://xmlns.com/foaf/0.1/", "@context": { "foaf:depiction": {"@type": "@id"}, "foaf": "http://xmlns.com/foaf/0.1/", "gh": "https://api.github.com/vocabulary#" "foaf:depiction": {"@type": "@id"}, }, "gh": "https://api.github.com/ "@id": [{"f:valueof": "login"}, vocabulary#" {"f:prefix": "http://github.com/"}], }, "@ns": { "@id": "https://api.github.com/users/ "ns:default": "gh", gkellogg", "ns:replace": {"avatar_url": "foaf:depiction", "name": "@type": ["gh:User", “foaf:Person”],"foaf:name"} "foaf:name": "Gregg Kellogg", }, "foaf:depiction": "http://...", "@only": ["avatar_url", "name", "followers"], “gh:followers”: 35 "@type": ["gh:User", "foaf:Person"] } }} * json-ld-macros courtesy of Antonio Garrote
44. 44. The “LD” in JSON-LD• IRIs are first-class http://greggkellogg.net/foaf citizens { "@context": "http://json-ld.org/contexts/person", "@id": "http://greggkellogg.net/foaf#me", "@type": "Person", "name": "Gregg Kellogg", "knows": "http://www.markus-lanthaler.com/" } http://www.markus-lanthaler.com { "@context": "http://json-ld.org/contexts/person", "@id": "http://www.markus-lanthaler.com/", "@type": "Person", "name": "Markus Lanthaler", "knows" "http://greggkellogg.net/foaf#me" }
45. 45. The “LD” in JSON-LD • IRIs are first-class http://greggkellogg.net/foaf citizens { "@context": "http://json-ld.org/contexts/person", • Object definitions may "@id": "http://greggkellogg.net/foaf#me", "@type": "Person", be referenced or "name": "Gregg Kellogg", "knows": "http://www.markus-lanthaler.com/" embedded } http://www.markus-lanthaler.com {{ "@context": "http://json-ld.org/contexts/person", "@context": "http://json-ld.org/contexts/person", "@id": "http://www.markus-lanthaler.com/", "@id": "http://greggkellogg.net/foaf#me", "@type": "Person", "@type": "Person", "name": "Markus Lanthaler", "name": "Gregg Kellogg", "knows" "http://greggkellogg.net/foaf#me" "knows": { } "@id": "http://www.markus-lanthaler.com/", "@type": "Person", "name": "Markus Lanthaler", "knows" "http://greggkellogg.net/foaf#me" }}
46. 46. RDF { "@context": "http://json-ld.org/contexts/person", "@id": "http://greggkellogg.net/foaf#me", "@type": "Person", "name": "Gregg Kellogg", "knows": { "@id": "http://www.markus-lanthaler.com/", "@type": "Person", "name": "Markus Lanthaler", "knows" "http://greggkellogg.net/foaf#me" }}
47. 47. RDF { "@context": "http://json-ld.org/contexts/person", "@id": "http://greggkellogg.net/foaf#me", "@type": "Person", "name": "Gregg Kellogg", "knows": { "@id": "http://www.markus-lanthaler.com/", "@type": "Person", "name": "Markus Lanthaler", "knows" "http://greggkellogg.net/foaf#me" }}
48. 48. RDF { "@context": "http://json-ld.org/contexts/person", "@id": "http://greggkellogg.net/foaf#me", "@type": "Person", "name": "Gregg Kellogg", "knows": { "@id": "http://www.markus-lanthaler.com/", "@type": "Person", "name": "Markus Lanthaler", "knows" "http://greggkellogg.net/foaf#me" }} @prefix: schema <http://schema.org/> . <http://greggkellogg.net/foaf#me> a schema:Person; schema:name “Gregg Kellogg”; shema:knows <http://www.markus-lanthaler.com/> . <http://www.markus-lanthaler.com/> a schema:Person schema:name “Markus Lanthaler” schema:knows <http://greggkellogg.net/foaf#me> .
49. 49. JSON-LD API• compact – use minimal representation using a supplied @context• expand – expand to full form, removing embedded @context definitions• frame – query for JSON-LD• fromRDF/toRDF
50. 50. More Information json-ld.org JavaScript Ruby w3c Python PHP JavaGregg Kellogg [email protected]://greggkellogg.net/http://www.slideshare.net/gkellogg1/json-for-linked-data@gkellogg