linkeddata#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 +1,98 @@
+import jsonld from 'jsonld'
+
+import { arrayToStatements } from './util'
+
+/**
+ * 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|NamedNode|BlankNode|Collection}
+ */
+export function jsonldObjectToTerm (kb, obj) {
+  if (typeof obj === 'string') {
+    return kb.rdfFactory.literal(obj)
+  }
+
+  if (Object.prototype.hasOwnProperty.call(obj, '@list')) {
+    if (kb.rdfFactory.supports["COLLECTIONS"] === true) {
+      return listToCollection(kb, obj['@list'])
+    }
+
+    return listToStatements(kb, obj)
+  }
+
+  if (Object.prototype.hasOwnProperty.call(obj, '@id')) {
+    return kb.rdfFactory.namedNode(obj['@id'])
+  }
+
+  if (Object.prototype.hasOwnProperty.call(obj, '@language')) {
+    return kb.rdfFactory.literal(obj['@value'], obj['@language'])
+  }
+
+  if (Object.prototype.hasOwnProperty.call(obj, '@type')) {
+    return kb.rdfFactory.literal(obj['@value'], kb.rdfFactory.namedNode(obj['@type']))
+  }
+
+  if (Object.prototype.hasOwnProperty.call(obj, '@value')) {
+    return kb.rdfFactory.literal(obj['@value'])
+  }
+
+  return kb.rdfFactory.literal(obj)
+}
+
+/**
+ * Adds the statements in a json-ld list object to {kb}.
+ */
+function listToStatements (kb, obj) {
+  const listId = obj['@id'] ? kb.rdfFactory.namedNode(obj['@id']) : kb.rdfFactory.blankNode()
+
+  const items = obj['@list'].map((listItem => jsonldObjectToTerm(kb, listItem)))
+  const statements = arrayToStatements(kb.rdfFactory, listId, items)
+  kb.addAll(statements)
+
+  return listId
+}
+
+function listToCollection (kb, obj) {
+  if (!Array.isArray(obj)) {
+    throw new TypeError("Object must be an array")
+  }
+  return kb.rdfFactory.collection(obj.map((o) => jsonldObjectToTerm(kb, o)))
+}
+
+/**
+ * Takes a json-ld formatted string {str} and adds its statements to {kb}.
+ *
+ * Ensure that {kb.rdfFactory} is a DataFactory.
+ */
+export default function jsonldParser (str, kb, base, callback) {
+  const baseString = base && 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.rdfFactory.namedNode(flatResource['@id'])
+        : kb.rdfFactory.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.rdfFactory.quad(id, kb.rdfFactory.namedNode(property), jsonldObjectToTerm(kb, value[i])))
+          }
+        } else {
+          kb.addStatement(kb.rdfFactory.quad(id, kb.rdfFactory.namedNode(property), jsonldObjectToTerm(kb, value)))
+        }
+      }
+
+      return kb
+    }, kb))
+    .then(callback)
+    .catch(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')
     }

src/util.js

@@ -2,6 +2,7 @@
  * Utility functions for $rdf
  * @module util
  */
+import { jsonldObjectToTerm } from './jsonldparser'
 import { docpart } from './uri'
 import log from './log'
 import * as uri from './uri'
@@ -91,6 +92,39 @@ export function AJAR_handleNewTerm (kb, p, requestedBy) {
   return sf.fetch(docuri, { referringTerm: requestedBy })
 }
 
+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'
+}
+
+/**
+ * Expands an array of Terms to a set of statements representing the rdf:list.
+ * @param rdfFactory - The factory to use
+ * @param {NamedNode|BlankNode} subject - The iri of the first list item.
+ * @param {Term[]} data - The terms to expand into the list.
+ * @return {Statement[]} - The {data} as a set of statements.
+ */
+export function arrayToStatements(rdfFactory, subject, data) {
+  const statements = []
+
+  data.reduce((id, listObj, i, listData) => {
+    statements.push(rdfFactory.quad(id, rdfFactory.namedNode(rdf.first), listData[i]))
+
+    let nextNode
+    if (i < listData.length - 1) {
+      nextNode = rdfFactory.blankNode()
+      statements.push(rdfFactory.quad(id, rdfFactory.namedNode(rdf.rest), nextNode))
+    } else {
+      statements.push(rdfFactory.quad(id, rdfFactory.namedNode(rdf.rest), rdfFactory.namedNode(rdf.nil)))
+    }
+
+    return nextNode
+  }, subject)
+
+  return statements
+}
+
 export function ArrayIndexOf (arr, item, i) {
   i || (i = 0)
   var length = arr.length