Parse rdf:version

Author: rubensworks

README.md

@@ -48,6 +48,19 @@ fs.createReadStream('myfile.rdf')
   .on('end', () => console.log('All triples were parsed!'));
 ```
 
+### Read all version attribute values
+
+```javascript
+const myParser = new RdfXmlParser();
+
+fs.createReadStream('myfile.rdf')
+  .pipe(myParser)
+  .on('data', console.log)
+  .on('version', console.log) // Log rdf:version attribute values
+  .on('error', console.error)
+  .on('end', () => console.log('All triples were parsed!'));
+```
+
 ### Manually write strings to the parser
 
 ```javascript

lib/RdfXmlParser.ts

@@ -264,7 +264,9 @@ export class RdfXmlParser extends Transform implements RDF.Sink<EventEmitter, RD
     let explicitType: string = null;
     for (const attributeKey in tag.attributes) {
       const attribute = tag.attributes[attributeKey];
-      if (parentTag && attribute.uri === RdfXmlParser.RDF) {
+      if (attribute.uri === RdfXmlParser.RDF && attribute.local === 'version') {
+        this.emit('version', attribute.value);
+      } else if (parentTag && attribute.uri === RdfXmlParser.RDF) {
         switch (attribute.local) {
         case 'about':
           if (activeSubjectValue) {
@@ -435,7 +437,9 @@ while ${attribute.value} and ${activeSubjectValue} where found.`);
     const objects: (RDF.NamedNode | RDF.BlankNode | RDF.Literal)[] = [];
     for (const propertyAttributeKey in tag.attributes) {
       const propertyAttribute = tag.attributes[propertyAttributeKey];
-      if (propertyAttribute.uri === RdfXmlParser.RDF) {
+      if (propertyAttribute.uri === RdfXmlParser.RDF && propertyAttribute.local === 'version') {
+        this.emit('version', propertyAttribute.value);
+      } else if (propertyAttribute.uri === RdfXmlParser.RDF) {
         switch (propertyAttribute.local) {
         case 'resource':
           if (activeSubSubjectValue) {

test/RdfXmlParser-test.ts

@@ -2473,6 +2473,55 @@ abc`)).rejects.toBeTruthy();
             quad('http://ex.org/i/subject', 'http://anon.org/o/hasBlankNode', '_:yellow"'),
           ]);
       });
+
+      it('rdf:version attribute on the root tag', async () => {
+        const cb = jest.fn();
+        parser.on('version', cb);
+        await parse(parser, `<?xml version="1.0"?>
+<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
+            xmlns:dc="http://purl.org/dc/elements/1.1/"
+            xmlns:ex="http://example.org/stuff/1.0/"
+            rdf:version="1.2">
+  <rdf:Description>
+    <ex:editor>
+      <rdf:Description></rdf:Description>
+    </ex:editor>
+  </rdf:Description>
+</rdf:RDF>`);
+        return expect(cb).toHaveBeenCalledWith('1.2');
+      });
+
+      it('rdf:version attribute a property tag', async () => {
+        const cb = jest.fn();
+        parser.on('version', cb);
+        await parse(parser, `<?xml version="1.0"?>
+<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
+            xmlns:dc="http://purl.org/dc/elements/1.1/"
+            xmlns:ex="http://example.org/stuff/1.0/">
+  <rdf:Description>
+    <ex:editor rdf:version="1.2">
+      <rdf:Description></rdf:Description>
+    </ex:editor>
+  </rdf:Description>
+</rdf:RDF>`);
+        return expect(cb).toHaveBeenCalledWith('1.2');
+      });
+
+      it('rdf:version attribute an internal tag', async () => {
+        const cb = jest.fn();
+        parser.on('version', cb);
+        await parse(parser, `<?xml version="1.0"?>
+<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
+            xmlns:dc="http://purl.org/dc/elements/1.1/"
+            xmlns:ex="http://example.org/stuff/1.0/">
+  <rdf:Description>
+    <ex:editor>
+      <rdf:Description rdf:version="1.2"></rdf:Description>
+    </ex:editor>
+  </rdf:Description>
+</rdf:RDF>`);
+        return expect(cb).toHaveBeenCalledWith('1.2');
+      });
     });
 
     describe('streaming-wise', () => {