Support for rr:subject

src/helper/vocabulary.js

@@ -0,0 +1,20 @@
+function createNamespace(baseUri, localNames) {
+  const namespace = {};
+  for (const localName of localNames) {
+    namespace[localName] = `${baseUri}${localName}`;
+  }
+  return namespace;
+}
+
+const RR = createNamespace('http://www.w3.org/ns/r2rml#', [
+  'BlankNode',
+  'IRI',
+  'Literal',
+]);
+
+const RDF = createNamespace('http://www.w3.org/1999/02/22-rdf-syntax-ns#', [
+  'type',
+]);
+
+module.exports.RR = RR;
+module.exports.RDF = RDF;

src/input-parser/JSONParser.js

@@ -15,13 +15,17 @@ class JsonParser {
   getData(index, selector) {
     const sel = selector.replace(/^PATH~/, '');
     const splitter = sel.startsWith('[') ? '' : '.';
-    return JSONPath({
+    const arr = JSONPath({
       path: `${this.paths[index]}${splitter}${sel}`,
       json: this.json,
       resultType: selector.startsWith('PATH~') ? 'pointer' : 'value',
     })
-      .filter((e) => e !== null && e !== undefined) // null values are ignored (undefined shouldn't happens since input is json)
-      .map((e) => e.toString()); // return only strings
+      .filter((e) => e !== null && e !== undefined); // null values are ignored (undefined shouldn't happens since input is json)
+
+    if (arr.length === 1 && Array.isArray(arr[0])) {
+      return arr[0].map((e) => e.toString());
+    }
+    return arr.map((e) => e.toString());
   }
 }
 

src/input-parser/parser.js

@@ -1,6 +1,7 @@
 const tags = require('language-tags');
 
 const helper = require('./helper.js');
+const { RR, RDF } = require('../helper/vocabulary');
 const prefixhelper = require('../helper/prefixHelper.js');
 const functionHelper = require('../function/function.js');
 const XMLParser = require('./XMLParser.js');
@@ -92,30 +93,17 @@ const iterateFile = async (Parser, data, currObject, prefixes, options) => {
     }
   }
   const functionClassMap = (subjectMap.class && Object.keys(subjectMap.class).length > 1) ? subjectMap.class : undefined;
-  let idTemplate;
-  if (subjectMap.template) {
-    idTemplate = subjectMap.template;
-  }
-  let reference;
-  if (subjectMap.reference) {
-    reference = subjectMap.reference;
-  }
-
-  let constant;
-  if (subjectMap.constant) {
-    constant = subjectMap.constant;
-  }
 
   let result = [];
   const iteratorNumber = Parser.getCount();
-  if (reference) {
+  if (subjectMap.reference) {
     for (let i = 0; i < iteratorNumber; i++) {
       if (functionClassMap) {
         type = await helper.subjFunctionExecution(Parser, functionClassMap, prefixes, data, i, options);
       }
       let obj = {};
       count++;
-      let nodes = getDataFromParser(Parser, i, reference, options);
+      let nodes = getDataFromParser(Parser, i, subjectMap.reference, options);
       nodes = helper.addArray(nodes);
       // eslint-disable-next-line no-loop-func
       // needs to be done in sequence, since result.push() is done.
@@ -137,30 +125,30 @@ const iterateFile = async (Parser, data, currObject, prefixes, options) => {
         }
       }
     }
-  } else if (idTemplate) {
+  } else if (subjectMap.template) {
     count++;
     for (let i = 0; i < iteratorNumber; i++) {
       if (functionClassMap) {
         type = await helper.subjFunctionExecution(Parser, functionClassMap, prefixes, data, i, options);
       }
       let obj = {};
-      const ids = calculateTemplate(Parser, i, idTemplate, prefixes, undefined, options);
+      const ids = calculateTemplate(Parser, i, subjectMap.template, prefixes, undefined, options);
       for (let id of ids) {
         if (subjectMap.termType) {
           const template = prefixhelper.replacePrefixWithURL(subjectMap.termType['@id'], prefixes);
           switch (template) {
-            case 'http://www.w3.org/ns/r2rml#BlankNode':
+            case RR.BlankNode:
               id = `_:${id}`;
               break;
-            case 'http://www.w3.org/ns/r2rml#IRI':
-              if ((!idTemplate && !reference) || (idTemplate && reference)) {
+            case RR.IRI:
+              if ((!subjectMap.template && !subjectMap.reference) || (subjectMap.template && subjectMap.reference)) {
                 throw ('Must use exactly one of - rr:template and rr:reference in SubjectMap!');
               }
               if (!helper.isURL(id)) {
                 id = helper.addBase(id, prefixes);
               }
               break;
-            case 'http://www.w3.org/ns/r2rml#Literal':
+            case RR.Literal:
               break;
             default:
               throw (`Don't know: ${subjectMap.termType['@id']}`);
@@ -191,31 +179,29 @@ const iterateFile = async (Parser, data, currObject, prefixes, options) => {
       writeParentPath(Parser, i, parents, obj, options);
       result.push(obj);
     }
-  } else if (subjectMap.termType) {
-    const termType = prefixhelper.replacePrefixWithURL(subjectMap.termType['@id'], prefixes);
-    if (termType === 'http://www.w3.org/ns/r2rml#BlankNode') {
-      // BlankNode with no template or id
-      for (let i = 0; i < iteratorNumber; i++) {
-        if (functionClassMap) {
-          type = await helper.subjFunctionExecution(Parser, functionClassMap, prefixes, data, i, options);
-        }
-        count++;
-        let obj = {};
-        if (constant) {
-          obj['@id'] = helper.getConstant(constant, prefixes);
-        }
-        if (type) {
-          obj['@type'] = type;
-        }
-        obj = await doObjectMappings(Parser, i, currObject, data, prefixes, obj, options);
-        if (!obj['@id']) {
-          obj['@id'] = `_:${encodeURIComponent(`${currObject['@id']}_${count}`)}`;
-        }
-        writeParentPath(Parser, i, parents, obj, options);
-        result.push(obj);
+  } else if (subjectMap.constant || (
+    subjectMap.termType
+    && prefixhelper.replacePrefixWithURL(subjectMap.termType['@id'], prefixes) === RR.BlankNode
+  )) {
+    // BlankNode with no template or id
+    for (let i = 0; i < iteratorNumber; i++) {
+      if (functionClassMap) {
+        type = await helper.subjFunctionExecution(Parser, functionClassMap, prefixes, data, i, options);
       }
-    } else {
-      throw new Error('????');
+      count++;
+      let obj = {};
+      if (subjectMap.constant) {
+        obj['@id'] = helper.getConstant(subjectMap.constant, prefixes);
+      }
+      if (type) {
+        obj['@type'] = type;
+      }
+      obj = await doObjectMappings(Parser, i, currObject, data, prefixes, obj, options);
+      if (!obj['@id']) {
+        obj['@id'] = `_:${encodeURIComponent(`${currObject['@id']}_${count}`)}`;
+      }
+      writeParentPath(Parser, i, parents, obj, options);
+      result.push(obj);
     }
   } else {
     throw new Error('Unsupported subjectmap');
@@ -308,12 +294,12 @@ const handleSingleMapping = async (Parser, index, obj, mapping, predicate, prefi
             if (termtype) {
               termtype = prefixhelper.replacePrefixWithURL(termtype, prefixes);
               switch (termtype) {
-                case 'http://www.w3.org/ns/r2rml#BlankNode':
+                case RR.BlankNode:
                   t = {
                     '@id': `_:${t}`,
                   };
                   break;
-                case 'http://www.w3.org/ns/r2rml#IRI':
+                case RR.IRI:
                   if (!helper.isURL(t)) {
                     t = {
                       '@id': helper.addBase(t, prefixes),
@@ -324,7 +310,7 @@ const handleSingleMapping = async (Parser, index, obj, mapping, predicate, prefi
                     };
                   }
                   break;
-                case 'http://www.w3.org/ns/r2rml#Literal':
+                case RR.Literal:
                   break;
                 default:
                   throw (`Don't know: ${termtype['@id']}`);
@@ -354,7 +340,7 @@ const handleSingleMapping = async (Parser, index, obj, mapping, predicate, prefi
           constant = helper.cutArray(constant);
           constant = helper.getConstant(constant, prefixes);
 
-          if (prefixhelper.replacePrefixWithURL(predicate, prefixes) !== 'http://www.w3.org/1999/02/22-rdf-syntax-ns#type' && termtype && prefixhelper.replacePrefixWithURL(termtype, prefixes) === 'http://www.w3.org/ns/r2rml#IRI') {
+          if (prefixhelper.replacePrefixWithURL(predicate, prefixes) !== RDF.type && termtype && prefixhelper.replacePrefixWithURL(termtype, prefixes) === RR.IRI) {
             if (!helper.isURL(constant)) {
               constant = {
                 '@id': helper.addBase(constant, prefixes),
@@ -431,7 +417,7 @@ const calculateTemplate = (Parser, index, template, prefixes, termType, options)
   for (const combin in allComb) {
     let finTemp = template;
     for (const found in allComb[combin]) {
-      if (!termType || termType !== 'http://www.w3.org/ns/r2rml#Literal') {
+      if (!termType || termType !== RR.Literal) {
         allComb[combin][found] = helper.toURIComponent(allComb[combin][found]);
       }
       finTemp = finTemp.replace(`{${words[found]}}`, allComb[combin][found]);

tests/arrayValueMapping/input.json

@@ -0,0 +1,4 @@
+{
+  "name":"Tom A.",
+  "favorite-numbers": [ 3, 33, 13 ]
+}

tests/arrayValueMapping/mapping.ttl

@@ -0,0 +1,33 @@
+@prefix rr: <http://www.w3.org/ns/r2rml#> .
+@prefix rml: <http://semweb.mmlab.be/ns/rml#> .
+@prefix schema: <http://schema.org/> .
+@prefix ql: <http://semweb.mmlab.be/ns/ql#> .
+@base <http://sti2.at/> . #the base for the classes
+
+<#LOGICALSOURCE>
+rml:source "./tests/arrayValueMapping/input.json";
+rml:referenceFormulation ql:JSONPath;
+rml:iterator "$".
+
+
+<#Mapping>
+  rml:logicalSource <#LOGICALSOURCE>;
+
+   rr:subjectMap [
+      rr:termType rr:BlankNode;
+      rr:class schema:Person;
+   ];
+
+
+  rr:predicateObjectMap [
+      rr:predicateMap [ rr:constant "http://schema.org/name" ];
+      rr:objectMap [ rml:reference "name" ];
+  ];
+
+  rr:predicateObjectMap [
+      rr:predicateMap [ rr:constant "http://example.com/favorite-numbers" ];
+      rr:objectMap [
+        rml:reference "favorite-numbers" ;
+        rr:datatype "http://www.w3.org/2001/XMLSchema#integer" ;
+      ];
+  ] .

tests/arrayValueMapping/out.json

@@ -0,0 +1,21 @@
+[
+  {
+    "@type": "http://schema.org/Person",
+    "http://schema.org/name": "Tom A.",
+    "http://example.com/favorite-numbers": [
+      {
+        "@value": "3",
+        "@type": "http://www.w3.org/2001/XMLSchema#integer"
+      },
+      {
+        "@type": "http://www.w3.org/2001/XMLSchema#integer",
+        "@value": "33"
+      },
+      {
+        "@type": "http://www.w3.org/2001/XMLSchema#integer",
+        "@value": "13"
+      }
+    ],
+    "@id": "_:http%3A%2F%2Fsti2.at%2F%23Mapping_1"
+  }
+]

tests/constantSubjectMapping/input.json

@@ -0,0 +1,4 @@
+{
+  "name":"Tom A.",
+  "age":15
+}

tests/constantSubjectMapping/mapping.ttl

@@ -0,0 +1,29 @@
+@prefix rr: <http://www.w3.org/ns/r2rml#> .
+@prefix rml: <http://semweb.mmlab.be/ns/rml#> .
+@prefix schema: <http://schema.org/> .
+@prefix ql: <http://semweb.mmlab.be/ns/ql#> .
+@base <http://sti2.at/> . #the base for the classes
+
+
+<#LOGICALSOURCE>
+rml:source "./tests/constantSubjectMapping/input.json";
+rml:referenceFormulation ql:JSONPath;
+rml:iterator "$".
+
+<#Mapping>
+rml:logicalSource <#LOGICALSOURCE>;
+
+ rr:subjectMap [
+    rr:constant "http://example.com/data/1234";
+    rr:class schema:Person;
+ ];
+
+rr:predicateObjectMap [
+    rr:predicateMap [rr:constant "http://schema.org/name"];
+    rr:objectMap [ rml:reference "name" ];
+];
+
+rr:predicateObjectMap [
+    rr:predicate schema:age;
+    rr:objectMap [ rml:reference "age" ];
+].

tests/constantSubjectMapping/out.json

@@ -0,0 +1,8 @@
+[
+  {
+    "@id": "http://example.com/data/1234",
+    "@type": "http://schema.org/Person",
+    "http://schema.org/name": "Tom A.",
+    "http://schema.org/age": "15"
+  }
+]

tests/test.js

@@ -39,6 +39,32 @@ it('Basic straight double mapping', async () => {
   assert.equal(result.length, 2);
 });
 
+it('Array Value mapping', async () => {
+  const options = {};
+  let result = await parser.parseFile('./tests/arrayValueMapping/mapping.ttl', './tests/arrayValueMapping/out.json', options).catch((err) => { console.log(err); });
+  result = helper.cutArray(result);
+  assert.equal(result['http://schema.org/name'], 'Tom A.');
+  assert.equal(result['http://example.com/favorite-numbers'].length, 3);
+  assert.equal(result['http://example.com/favorite-numbers'][0]['@value'], '3');
+  assert.equal(result['http://example.com/favorite-numbers'][0]['@type'], 'http://www.w3.org/2001/XMLSchema#integer');
+  assert.equal(result['http://example.com/favorite-numbers'][1]['@value'], '33');
+  assert.equal(result['http://example.com/favorite-numbers'][1]['@type'], 'http://www.w3.org/2001/XMLSchema#integer');
+  assert.equal(result['http://example.com/favorite-numbers'][2]['@value'], '13');
+  assert.equal(result['http://example.com/favorite-numbers'][2]['@type'], 'http://www.w3.org/2001/XMLSchema#integer');
+  assert.equal(result['@type'], 'http://schema.org/Person');
+  assert.equal(Object.keys(result).length, 4);
+});
+
+it('Constant subject mapping', async () => {
+  const options = {};
+  let result = await parser.parseFile('./tests/constantSubjectMapping/mapping.ttl', './tests/constantSubjectMapping/out.json', options).catch((err) => { console.log(err); });
+  result = helper.cutArray(result);
+  assert.equal(result['http://schema.org/name'], 'Tom A.');
+  assert.equal(result['@type'], 'http://schema.org/Person');
+  assert.equal(result['@id'], 'http://example.com/data/1234');
+  assert.equal(Object.keys(result).length, 4);
+});
+
 it('Live mapping', async () => {
   const options = {
     //  baseMapping:["http://sti2.at/#SPORTSmapping"],