#349 Use jsonld package without n3 package

package.json

@@ -34,7 +34,7 @@
   "dependencies": {
     "@babel/runtime": "^7.5.5",
     "async": "^3.1.x",
-    "jsonld": "^1.6.2",
+    "jsonld": "^1.8.0",
     "n3": "^1.2.0",
     "solid-auth-cli": "^1.0.8",
     "solid-auth-client": "^2.3.0",

src/jsonldparser.js

@@ -0,0 +1,96 @@
+import jsonld from 'jsonld'
+
+const rdf = {
+  first: 'http://www.w3.org/1999/02/22-rdf-syntax-ns#first',
+  rest: 'http://www.w3.org/1999/02/22-rdf-syntax-ns#rest',
+  nil: 'http://www.w3.org/1999/02/22-rdf-syntax-ns#nil'
+}
+
+/**
+ * Parses json-ld formatted JS objects to a rdf Term.
+ * @param kb - The DataFactory to use.
+ * @param obj - The json-ld object to process.
+ * @return {Literal|Literal|Literal|NamedNode|NamedNode|NamedNode}
+ */
+export function jsonldObjectToTerm (kb, obj) {
+  if (typeof obj === 'string') {
+    return kb.literal(obj)
+  }
+
+  if (Object.prototype.hasOwnProperty.call(obj, '@list')) {
+    return listToStatements(kb, obj)
+  }
+
+  if (Object.prototype.hasOwnProperty.call(obj, '@id')) {
+    return kb.namedNode(obj['@id'])
+  }
+
+  if (Object.prototype.hasOwnProperty.call(obj, '@language')) {
+    return kb.literal(obj['@value'], obj['@language'])
+  }
+
+  if (Object.prototype.hasOwnProperty.call(obj, '@type')) {
+    return kb.literal(obj['@value'], kb.namedNode(obj['@type']))
+  }
+
+  return kb.literal(obj['@value'])
+}
+
+/**
+ * Adds the statements in a json-ld list object to {kb}.
+ */
+function listToStatements (kb, obj) {
+  const listId = obj['@id'] ? kb.namedNode(obj['@id']) : kb.blankNode()
+
+  obj['@list'].reduce((id, listObj, i, listArr) => {
+    kb.addStatement(kb.quad(id, kb.namedNode(rdf.first), jsonldObjectToTerm(kb, listArr[i])))
+
+    let nextNode
+    if (i < listArr.length - 1) {
+      nextNode = kb.blankNode()
+      kb.addStatement(kb.quad(id, kb.namedNode(rdf.rest), nextNode))
+    } else {
+      kb.addStatement(kb.quad(id, kb.namedNode(rdf.rest), kb.namedNode(rdf.nil)))
+    }
+
+    return nextNode
+  }, listId)
+
+  return listId
+}
+
+/**
+ * Takes a json-ld formatted string {str} and adds its statements to {kb}.
+ *
+ * Make sure that kb implements the DataFactory interface.
+ */
+export default function jsonldParser (str, kb, base, callback) {
+  const baseString = Object.prototype.hasOwnProperty.call(base, 'termType')
+    ? base.value
+    : base
+
+  return jsonld
+    .flatten(JSON.parse(str), null, { base: baseString })
+    .then((flattened) => flattened.reduce((store, flatResource) => {
+      const id = flatResource['@id']
+        ? kb.namedNode(flatResource['@id'])
+        : kb.blankNode()
+
+      for (const property of Object.keys(flatResource)) {
+        if (property === '@id') {
+          continue
+        }
+        const value = flatResource[property]
+        if (Array.isArray(value)) {
+          for (let i = 0; i < value.length; i++) {
+            kb.addStatement(kb.quad(id, kb.namedNode(property), jsonldObjectToTerm(kb, value[i])))
+          }
+        } else {
+          kb.addStatement(kb.quad(id, kb.namedNode(property), jsonldObjectToTerm(kb, value)))
+        }
+      }
+
+      return kb
+    }, kb))
+    .finally(callback)
+}

src/parse.js

@@ -1,10 +1,7 @@
-import BlankNode from './blank-node'
 import DataFactory from './data-factory'
-import jsonld from 'jsonld'
-import Literal from './literal'
+import jsonldParser from './jsonldparser'
 import { Parser as N3jsParser } from 'n3'  // @@ Goal: remove this dependency
 import N3Parser from './n3parser'
-import NamedNode from './named-node'
 import { parseRDFaDOM } from './rdfaparser'
 import RDFParser from './rdfxmlparser'
 import sparqlUpdateParser from './patch-parser'
@@ -37,24 +34,12 @@ export default function parse (str, kb, base, contentType, callback) {
     } else if (contentType === 'application/sparql-update') { // @@ we handle a subset
       sparqlUpdateParser(str, kb, base)
       executeCallback()
-    } else if (contentType === 'application/ld+json' ||
-               contentType === 'application/nquads' ||
+    } else if (contentType === 'application/ld+json') {
+      jsonldParser(str, kb, base, executeCallback)
+    } else if (contentType === 'application/nquads' ||
                contentType === 'application/n-quads') {
       var n3Parser = new N3jsParser({ factory: DataFactory })
-      var triples = []
-      if (contentType === 'application/ld+json') {
-        var jsonDocument
-        try {
-          jsonDocument = JSON.parse(str)
-        } catch (parseErr) {
-          return callback(parseErr, null)
-        }
-        jsonld.toRDF(jsonDocument,
-          {format: 'application/nquads', base},
-          nquadCallback)
-      } else {
-        nquadCallback(null, str)
-      }
+      nquadCallback(null, str)
     } else {
       throw new Error("Don't know how to parse " + contentType + ' yet')
     }

tests/unit/parse-test.js

@@ -41,20 +41,103 @@ describe('Parse', () => {
             "homepage": {
               "@id": "http://xmlns.com/foaf/0.1/homepage",
               "@type": "@id"
-            }
+            },
+            "name": {
+              "@id": "http://xmlns.com/foaf/0.1/name",
+              "@container": "@language"
+            },
+            "height": {
+              "@id": "http://schema.org/height",
+              "@type": "xsd:float"
+            },
+            "list": {
+              "@id": "https://example.org/ns#listProp",
+              "@container": "@list"
+            },
+            "xsd": "http://www.w3.org/2001/XMLSchema#"
           },
           "@id": "../#me",
-          "homepage": "xyz"
+          "homepage": "xyz",
+          "name": {
+            "en": "The Queen",
+            "de": [ "Die Königin", "Ihre Majestät" ]
+          },
+          "height": "173.9",
+          "list": [
+            "list item 0",
+            "list item 1",
+            "list item 2"
+          ]
         }`
         store = DataFactory.graph()
         parse(content, store, base, mimeType, done)
       })
 
       it('uses the specified base IRI', () => {
-        expect(store.statements).to.have.length(1);
-        const statement = store.statements[0]
-        expect(statement.subject.value).to.equal('https://www.example.org/#me')
-        expect(statement.object.value).to.equal('https://www.example.org/abc/xyz')
+        const homePageHeight = 5 // homepage + height + 3 x name
+        const list = 2 * 3 + 1 // (rdf:first + rdf:rest) * 3 items + listProp
+        expect(store.statements).to.have.length(homePageHeight + list);
+
+        const height = store.statements[0]
+        expect(height.subject.value).to.equal('https://www.example.org/#me')
+        expect(height.predicate.value).to.equal('http://schema.org/height')
+        expect(height.object.datatype.value).to.equal('http://www.w3.org/2001/XMLSchema#float')
+        expect(height.object.value).to.equal('173.9')
+
+        const homepage = store.statements[1]
+        expect(homepage.subject.value).to.equal('https://www.example.org/#me')
+        expect(homepage.predicate.value).to.equal('http://xmlns.com/foaf/0.1/homepage')
+        expect(homepage.object.value).to.equal('https://www.example.org/abc/xyz')
+
+        const nameDe1 = store.statements[2]
+        expect(nameDe1.subject.value).to.equal('https://www.example.org/#me')
+        expect(nameDe1.predicate.value).to.equal('http://xmlns.com/foaf/0.1/name')
+        expect(nameDe1.object.value).to.equal('Die Königin')
+
+        const nameDe2 = store.statements[3]
+        expect(nameDe2.subject.value).to.equal('https://www.example.org/#me')
+        expect(nameDe2.predicate.value).to.equal('http://xmlns.com/foaf/0.1/name')
+        expect(nameDe2.object.value).to.equal('Ihre Majestät')
+
+        const nameEn = store.statements[4]
+        expect(nameEn.subject.value).to.equal('https://www.example.org/#me')
+        expect(nameEn.predicate.value).to.equal('http://xmlns.com/foaf/0.1/name')
+        expect(nameEn.object.value).to.equal('The Queen')
+
+        const list0First = store.statements[5]
+        expect(list0First.subject.value).to.equal('n1')
+        expect(list0First.predicate.value).to.equal('http://www.w3.org/1999/02/22-rdf-syntax-ns#first')
+        expect(list0First.object.value).to.equal('list item 0')
+
+        const list0Rest = store.statements[6]
+        expect(list0Rest.subject.value).to.equal('n1')
+        expect(list0Rest.predicate.value).to.equal('http://www.w3.org/1999/02/22-rdf-syntax-ns#rest')
+        expect(list0Rest.object.value).to.equal(store.statements[7].subject.value)
+
+        const list1First = store.statements[7]
+        expect(list1First.subject.value).to.equal('n2')
+        expect(list1First.predicate.value).to.equal('http://www.w3.org/1999/02/22-rdf-syntax-ns#first')
+        expect(list1First.object.value).to.equal('list item 1')
+
+        const list1Rest = store.statements[8]
+        expect(list1Rest.subject.value).to.equal('n2')
+        expect(list1Rest.predicate.value).to.equal('http://www.w3.org/1999/02/22-rdf-syntax-ns#rest')
+        expect(list1Rest.object.value).to.equal(store.statements[9].subject.value)
+
+        const list2First = store.statements[9]
+        expect(list2First.subject.value).to.equal('n3')
+        expect(list2First.predicate.value).to.equal('http://www.w3.org/1999/02/22-rdf-syntax-ns#first')
+        expect(list2First.object.value).to.equal('list item 2')
+
+        const list2Rest = store.statements[10]
+        expect(list2Rest.subject.value).to.equal('n3')
+        expect(list2Rest.predicate.value).to.equal('http://www.w3.org/1999/02/22-rdf-syntax-ns#rest')
+        expect(list2Rest.object.value).to.equal('http://www.w3.org/1999/02/22-rdf-syntax-ns#nil')
+
+        const listProp = store.statements[11]
+        expect(listProp.subject.value).to.equal('https://www.example.org/#me')
+        expect(listProp.predicate.value).to.equal('https://example.org/ns#listProp')
+        expect(listProp.object.value).to.equal('n1')
       })
     })
   })