fixed XML serialization for children sub-elements (duplicates & externalreferences)

dhp-workflows/dhp-graph-provision/src/main/resources/eu/dnetlib/dhp/oa/provision/template/child.st

@@ -1,3 +1,3 @@
 <$name$$if(hasId)$ objidentifier="$id$"$else$$endif$>
-	$metadata:{$it$}$
+	$metadata:{ it | $it$ }$
 </$name$>

dhp-workflows/dhp-graph-provision/src/test/java/eu/dnetlib/dhp/oa/provision/XmlRecordFactoryTest.java

@@ -0,0 +1,47 @@
+package eu.dnetlib.dhp.oa.provision;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import eu.dnetlib.dhp.oa.provision.model.JoinedEntity;
+import eu.dnetlib.dhp.oa.provision.utils.ContextMapper;
+import eu.dnetlib.dhp.oa.provision.utils.XmlRecordFactory;
+import org.apache.commons.io.IOUtils;
+import org.dom4j.Document;
+import org.dom4j.DocumentException;
+import org.dom4j.io.SAXReader;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+import java.io.IOException;
+import java.io.StringReader;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class XmlRecordFactoryTest {
+
+    private static final String otherDsTypeId = "scholarcomminfra,infospace,pubsrepository::mock,entityregistry,entityregistry::projects,entityregistry::repositories,websource";
+
+    @Test
+    public void testXMLRecordFactory() throws IOException, DocumentException {
+
+        String json = IOUtils.toString(getClass().getResourceAsStream("joined_entity.json"));
+
+        assertNotNull(json);
+        JoinedEntity je = new ObjectMapper().readValue(json, JoinedEntity.class);
+        assertNotNull(je);
+
+        ContextMapper contextMapper = new ContextMapper();
+
+        XmlRecordFactory xmlRecordFactory = new XmlRecordFactory(contextMapper, false, XmlConverterJob.schemaLocation, otherDsTypeId);
+
+        String xml = xmlRecordFactory.build(je);
+
+        assertNotNull(xml);
+
+        Document doc = new SAXReader().read(new StringReader(xml));
+
+        assertNotNull(doc);
+
+        System.out.println(doc.asXML());
+
+    }
+}