improved parallelization on transformation job

dhp-workflows/dhp-aggregation/src/main/java/eu/dnetlib/dhp/transformation/TransformSparkJobNode.java

@@ -11,6 +11,9 @@ import java.util.Optional;
 
 import org.apache.commons.io.IOUtils;
 import org.apache.spark.SparkConf;
+import org.apache.spark.api.java.JavaRDD;
+import org.apache.spark.api.java.function.Function;
+import org.apache.spark.api.java.function.MapFunction;
 import org.apache.spark.sql.Dataset;
 import org.apache.spark.sql.Encoder;
 import org.apache.spark.sql.Encoders;
@@ -26,6 +29,7 @@ import eu.dnetlib.dhp.application.ArgumentApplicationParser;
 import eu.dnetlib.dhp.common.vocabulary.VocabularyGroup;
 import eu.dnetlib.dhp.message.MessageSender;
 import eu.dnetlib.dhp.schema.mdstore.MetadataRecord;
+import eu.dnetlib.dhp.transformation.xslt.XSLTTransformationFunction;
 import eu.dnetlib.dhp.utils.ISLookupClientFactory;
 import eu.dnetlib.enabling.is.lookup.rmi.ISLookUpService;
 
@@ -33,6 +37,8 @@ public class TransformSparkJobNode {
 
 	private static final Logger log = LoggerFactory.getLogger(TransformSparkJobNode.class);
 
+	private static int RECORDS_PER_TASK = 200;
+
 	public static void main(String[] args) throws Exception {
 
 		final ArgumentApplicationParser parser = new ArgumentApplicationParser(
@@ -67,6 +73,11 @@ public class TransformSparkJobNode {
 		final String dateOfTransformation = parser.get("dateOfTransformation");
 		log.info(String.format("dateOfTransformation: %s", dateOfTransformation));
 
+		final Integer rpt = Optional
+			.ofNullable(parser.get("recordsPerTask"))
+			.map(Integer::valueOf)
+			.orElse(RECORDS_PER_TASK);
+
 		final ISLookUpService isLookupService = ISLookupClientFactory.getLookUpService(isLookupUrl);
 
 		final VocabularyGroup vocabularies = VocabularyGroup.loadVocsFromIS(isLookupService);
@@ -79,12 +90,12 @@ public class TransformSparkJobNode {
 			isSparkSessionManaged,
 			spark -> {
 				transformRecords(
-					parser.getObjectMap(), isLookupService, spark, inputPath, outputBasePath);
+					parser.getObjectMap(), isLookupService, spark, inputPath, outputBasePath, rpt);
 			});
 	}
 
 	public static void transformRecords(final Map<String, String> args, final ISLookUpService isLookUpService,
-		final SparkSession spark, final String inputPath, final String outputBasePath)
+		final SparkSession spark, final String inputPath, final String outputBasePath, final Integer rpt)
 		throws DnetTransformationException, IOException {
 
 		final LongAccumulator totalItems = spark.sparkContext().longAccumulator(CONTENT_TOTALITEMS);
@@ -99,18 +110,25 @@ public class TransformSparkJobNode {
 		final String workflowId = args.get("workflowId");
 		log.info("workflowId is {}", workflowId);
 
-		final MessageSender messageSender = new MessageSender(dnetMessageManagerURL, workflowId);
+		MapFunction<MetadataRecord, MetadataRecord> x = TransformationFactory
-		try (AggregatorReport report = new AggregatorReport(messageSender)) {
+				.getTransformationPlugin(args, ct, isLookUpService);
-			try {
+
-				final Dataset<MetadataRecord> mdstore = spark
+		final Dataset<MetadataRecord> inputMDStore = spark
 			.read()
 			.format("parquet")
 			.load(inputPath)
-					.as(encoder)
+			.as(encoder);
-					.map(
+
-						TransformationFactory.getTransformationPlugin(args, ct, isLookUpService),
+		final long totalInput = inputMDStore.count();
-						encoder);
+
-				saveDataset(mdstore, outputBasePath + MDSTORE_DATA_PATH);
+		final MessageSender messageSender = new MessageSender(dnetMessageManagerURL, workflowId);
+		try (AggregatorReport report = new AggregatorReport(messageSender)) {
+			try {
+				JavaRDD<MetadataRecord> mdstore = inputMDStore
+					.javaRDD()
+					.repartition(getRepartitionNumber(totalInput, rpt))
+					.map((Function<MetadataRecord, MetadataRecord>) x::call);
+				saveDataset(spark.createDataset(mdstore.rdd(), encoder), outputBasePath + MDSTORE_DATA_PATH);
 
 				log.info("Transformed item " + ct.getProcessedItems().count());
 				log.info("Total item " + ct.getTotalItems().count());

dhp-workflows/dhp-aggregation/src/main/java/eu/dnetlib/dhp/transformation/xslt/XSLTTransformationFunction.java

@@ -2,6 +2,7 @@
 package eu.dnetlib.dhp.transformation.xslt;
 
 import java.io.ByteArrayInputStream;
+import java.io.Serializable;
 import java.io.StringWriter;
 import java.nio.charset.StandardCharsets;
 
@@ -15,7 +16,7 @@ import eu.dnetlib.dhp.common.vocabulary.VocabularyGroup;
 import eu.dnetlib.dhp.schema.mdstore.MetadataRecord;
 import net.sf.saxon.s9api.*;
 
-public class XSLTTransformationFunction implements MapFunction<MetadataRecord, MetadataRecord> {
+public class XSLTTransformationFunction implements MapFunction<MetadataRecord, MetadataRecord>, Serializable {
 
 	public final static String QNAME_BASE_URI = "http://eu/dnetlib/transform";
 
@@ -27,6 +28,8 @@ public class XSLTTransformationFunction implements MapFunction<MetadataRecord, M
 
 	private final long dateOfTransformation;
 
+	private final VocabularyGroup vocabularies;
+
 	public XSLTTransformationFunction(
 		final AggregationCounter aggregationCounter,
 		final String transformationRule,
@@ -35,6 +38,7 @@ public class XSLTTransformationFunction implements MapFunction<MetadataRecord, M
 		throws Exception {
 		this.aggregationCounter = aggregationCounter;
 		this.transformationRule = transformationRule;
+		this.vocabularies = vocabularies;
 		this.dateOfTransformation = dateOfTransformation;
 		cleanFunction = new Cleaner(vocabularies);
 	}
@@ -73,4 +77,24 @@ public class XSLTTransformationFunction implements MapFunction<MetadataRecord, M
 			throw new RuntimeException(e);
 		}
 	}
+
+	public AggregationCounter getAggregationCounter() {
+		return aggregationCounter;
+	}
+
+	public String getTransformationRule() {
+		return transformationRule;
+	}
+
+	public Cleaner getCleanFunction() {
+		return cleanFunction;
+	}
+
+	public long getDateOfTransformation() {
+		return dateOfTransformation;
+	}
+
+	public VocabularyGroup getVocabularies() {
+		return vocabularies;
+	}
 }

dhp-workflows/dhp-aggregation/src/main/resources/eu/dnetlib/dhp/transformation/oozie_app/workflow.xml

@@ -37,6 +37,12 @@
             <name>dnetMessageManagerURL</name>
             <description>The URI of the Dnet Message Manager</description>
         </property>
+        <property>
+            <name>recordsPerTask</name>
+            <value>200</value>
+            <description>The URI of the Dnet Message Manager</description>
+        </property>
+
     </parameters>
 
     <start to="BeginRead"/>
@@ -103,6 +109,7 @@
             <arg>--transformationPlugin</arg><arg>${transformationPlugin}</arg>
             <arg>--transformationRuleId</arg><arg>${transformationRuleId}</arg>
             <arg>--isLookupUrl</arg><arg>${isLookupUrl}</arg>
+            <arg>--recordsPerTask</arg><arg>${recordsPerTask}</arg>
             <arg>--workflowId</arg><arg>${workflowId}</arg>
             <arg>--dnetMessageManagerURL</arg><arg>${dnetMessageManagerURL}</arg>
         </spark>

dhp-workflows/dhp-aggregation/src/main/resources/eu/dnetlib/dhp/transformation/transformation_input_parameters.json

@@ -48,6 +48,12 @@
     "paramDescription": "the identifier of the dnet Workflow",
     "paramRequired": true
   },
+  {
+    "paramName": "rpt",
+    "paramLongName": "recordsPerTask",
+    "paramDescription": "the number of records transformed by a single Task",
+    "paramRequired": false
+  },
   {
     "paramName": "tp",
     "paramLongName": "transformationPlugin",

dhp-workflows/dhp-aggregation/src/test/java/eu/dnetlib/dhp/collection/GenerateNativeStoreSparkJobTest.java

@@ -180,7 +180,7 @@ public class GenerateNativeStoreSparkJobTest extends AbstractVocabularyTest {
 		TransformSparkJobNode
 			.transformRecords(
 				parameters, isLookUpService, spark, mdStoreV2.getHdfsPath() + MDSTORE_DATA_PATH,
-				mdStoreCleanedVersion.getHdfsPath());
+				mdStoreCleanedVersion.getHdfsPath(), 200);
 
 		final Encoder<MetadataRecord> encoder = Encoders.bean(MetadataRecord.class);
 		final Dataset<MetadataRecord> mOutput = spark

dhp-workflows/dhp-aggregation/src/test/java/eu/dnetlib/dhp/transformation/TransformationJobTest.java

@@ -167,7 +167,8 @@ public class TransformationJobTest extends AbstractVocabularyTest {
 
 			}).collect(Collectors.toMap(data -> data[0], data -> data[1]));
 
-			TransformSparkJobNode.transformRecords(parameters, isLookUpService, spark, mdstore_input, mdstore_output);
+			TransformSparkJobNode
+				.transformRecords(parameters, isLookUpService, spark, mdstore_input, mdstore_output, 200);
 
 			// TODO introduce useful assertions
 
@@ -221,7 +222,8 @@ public class TransformationJobTest extends AbstractVocabularyTest {
 
 			}).collect(Collectors.toMap(data -> data[0], data -> data[1]));
 
-			TransformSparkJobNode.transformRecords(parameters, isLookUpService, spark, mdstore_input, mdstore_output);
+			TransformSparkJobNode
+				.transformRecords(parameters, isLookUpService, spark, mdstore_input, mdstore_output, 200);
 
 			// TODO introduce useful assertions
 

dhp-workflows/dhp-aggregation/src/test/resources/eu/dnetlib/dhp/transform/zenodo_tr.xslt

@@ -1,16 +1,13 @@
-<xsl:stylesheet
+<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
-        version="2.0"
-        xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
-        xmlns:oai="http://www.openarchives.org/OAI/2.0/"
-        xmlns:oaf="http://namespace.openaire.eu/oaf"
                 xmlns:vocabulary="http://eu/dnetlib/transform/clean"
                 xmlns:dateCleaner="http://eu/dnetlib/transform/dateISO"
+                xmlns:oaf="http://namespace.openaire.eu/oaf"
+                xmlns:oai="http://www.openarchives.org/OAI/2.0/"
                 xmlns:dr="http://www.driver-repository.eu/namespace/dr"
-        exclude-result-prefixes="xsl vocabulary dateCleaner">
+                exclude-result-prefixes="xsl vocabulary dateCleaner" version="2.0">
     <xsl:param name="varOfficialName"/>
     <xsl:param name="varDsType"/>
     <xsl:param name="varDataSourceId"/>
-
     <xsl:param name="varFP7" select="'corda_______::'"/>
     <xsl:param name="varH2020" select="'corda__h2020::'"/>
     <xsl:param name="varAKA" select="'aka_________::'"/>
@@ -29,34 +26,27 @@
     <xsl:param name="varRCUK" select="'rcuk________::'"/>
     <xsl:param name="varSFI" select="'sfi_________::'"/>
     <xsl:param name="varSGOV"
-               select="'sgov________::'"/>     <!-- SGOV awaiting DOI from Pilar, found project ids not in CSV list? -->
+               select="'sgov________::'"/><!-- SGOV awaiting DOI from Pilar, found project ids not in CSV list? -->
     <xsl:param name="varSNSF" select="'snsf________::'"/>
-    <xsl:param name="varTARA" select="'taraexp_____::'"/>     <!-- TARA awaiting DOI from André -->
+    <xsl:param name="varTARA" select="'taraexp_____::'"/><!-- TARA awaiting DOI from André -->
     <xsl:param name="varTUBITAK" select="'tubitakf____::'"/>
     <xsl:param name="varWT" select="'wt__________::'"/>
-
     <xsl:param name="index" select="0"/>
     <xsl:param name="transDate" select="current-dateTime()"/>
-
-
     <xsl:template match="/">
         <xsl:variable name="datasourcePrefix" select="normalize-space(//oaf:datasourceprefix)"/>
         <xsl:call-template name="validRecord"/>
     </xsl:template>
-
-
     <xsl:template name="validRecord">
         <record>
             <xsl:apply-templates select="//*[local-name() = 'header']"/>
-
             <metadata>
                 <xsl:apply-templates select="//*[local-name() = 'metadata']//*[local-name() = 'resource']"/>
-
                 <xsl:if test="//*[local-name()='date']/@dateType='Available'">
-                    <xsl:variable name='varEmbargoEndDate'
+                    <xsl:variable name="varEmbargoEndDate"
                                   select="dateCleaner:dateISO(normalize-space(//*[local-name()='date'][@dateType='Available']))"/>
                     <xsl:choose>
-                        <xsl:when test="string-length($varEmbargoEndDate) > 0">
+                        <xsl:when test="string-length($varEmbargoEndDate) &gt; 0">
                             <oaf:embargoenddate>
                                 <xsl:value-of select="$varEmbargoEndDate"/>
                             </oaf:embargoenddate>
@@ -68,55 +58,44 @@
                         </xsl:otherwise>
                     </xsl:choose>
                 </xsl:if>
-
                 <dr:CobjCategory>
                     <xsl:variable name="varCobjCategory"
                                   select="vocabulary:clean( //*[local-name()='resourceType']/@resourceTypeGeneral, 'dnet:publication_resource')"/>
                     <xsl:variable name="varSuperType"
                                   select="vocabulary:clean( $varCobjCategory, 'dnet:result_typologies')"/>
-
                     <xsl:attribute name="type">
                         <xsl:value-of select="$varSuperType"/>
                     </xsl:attribute>
                     <xsl:value-of select="$varCobjCategory"/>
-                </dr:CobjCategory>
+                </dr:CobjCategory><!-- review status --><!-- Zenodo  -->
-
+                <xsl:variable name="varRefereedConvt"
-                <!-- review status -->
+                              select="for $i in (//*[local-name()='resourceType']/(., @resourceTypeGeneral), //*[local-name()='version'])         return vocabulary:clean(normalize-space($i), 'dnet:review_levels')"/>
-                <!-- Zenodo  -->
-                <xsl:variable name="varRefereedConvt" select="for $i in (//*[local-name()='resourceType']/(., @resourceTypeGeneral), //*[local-name()='version'])
-        return vocabulary:clean(normalize-space($i), 'dnet:review_levels')"/>
                 <xsl:variable name="varRefereedIdntf"
                               select="//*[local-name()=('identifier', 'alternateIdentifier')][matches(lower-case(.), '.*([\s\-\.\\_/:]|%[2-7][0-9A-F])pre([\s\-\.\\_/:]|%[2-7][0-9A-F])?prints?([\s\-\.\\_/:%].*|$)')]/'0002' "/>
                 <xsl:variable name="varRefereedReltn"
                               select="//*[local-name()='relatedIdentifier'][./@relationType/lower-case(.)='isreviewedby']/'0001' "/>
-                <xsl:variable name="varRefereedVersn" select="(//*[local-name()='version'][matches(lower-case(.), '.*peer[\s\-\.\\_/:%]?reviewed.*')]/'0001',
+                <xsl:variable name="varRefereedVersn"
-        //*[local-name()='version'][matches(normalize-space(lower-case(.)), '^(v|vs|version|rel|release)?[\s\.\-_]*0$')]/'0002',
+                              select="(//*[local-name()='version'][matches(lower-case(.), '.*peer[\s\-\.\\_/:%]?reviewed.*')]/'0001',         //*[local-name()='version'][matches(normalize-space(lower-case(.)), '^(v|vs|version|rel|release)?[\s\.\-_]*0$')]/'0002',         //*[local-name()='version'][matches(lower-case(.), '(^|[\s\-\.\\_/:%].*)(beta|draft|trial|test)([\s\-\.\\_/:%].*|$)')]/'0002',         //*[local-name()='version'][matches(lower-case(.), '.*submi(tted|ssion|ttal).*')]/'0002') "/>
-        //*[local-name()='version'][matches(lower-case(.), '(^|[\s\-\.\\_/:%].*)(beta|draft|trial|test)([\s\-\.\\_/:%].*|$)')]/'0002',
+                <xsl:variable name="varRefereedOther"
-        //*[local-name()='version'][matches(lower-case(.), '.*submi(tted|ssion|ttal).*')]/'0002') "/>
+                              select="(//*[local-name()='publisher'][matches(lower-case(.), '.*[\s\-\.\\_/:%]pre[\s\-\.\\_/:%]?prints?([\s\-\.\\_/:%].*|$)')]/'0002',         //*[local-name()='description'][matches(lower-case(.), '^peer[\s\-\.\\_/:%]?reviewed$')]/'0001',         //*[local-name()='description'][matches(lower-case(.), '^pre[\s\-\.\\_/:%]?prints?$')]/'0002') "/>
-                <xsl:variable name="varRefereedOther" select="(//*[local-name()='publisher'][matches(lower-case(.), '.*[\s\-\.\\_/:%]pre[\s\-\.\\_/:%]?prints?([\s\-\.\\_/:%].*|$)')]/'0002',
-        //*[local-name()='description'][matches(lower-case(.), '^peer[\s\-\.\\_/:%]?reviewed$')]/'0001',
-        //*[local-name()='description'][matches(lower-case(.), '^pre[\s\-\.\\_/:%]?prints?$')]/'0002') "/>
                 <xsl:variable name="varRefereed"
                               select="($varRefereedConvt, $varRefereedIdntf, $varRefereedReltn, $varRefereedVersn, $varRefereedOther)"/>
                 <xsl:choose>
-                    <xsl:when test="count($varRefereed[. = '0001']) > 0">
+                    <xsl:when test="count($varRefereed[. = '0001']) &gt; 0">
                         <oaf:refereed>
                             <xsl:value-of select="'0001'"/>
                         </oaf:refereed>
                     </xsl:when>
-                    <xsl:when test="count($varRefereed[. = '0002']) > 0">
+                    <xsl:when test="count($varRefereed[. = '0002']) &gt; 0">
                         <oaf:refereed>
                             <xsl:value-of select="'0002'"/>
                         </oaf:refereed>
                     </xsl:when>
                 </xsl:choose>
-
                 <oaf:dateAccepted>
-                    <xsl:value-of
+                    <xsl:value-of select="dateCleaner:dateISO(normalize-space(//*[local-name()='publicationYear']))"/>
-                            select="dateCleaner:dateISO(normalize-space(//*[local-name()='publicationYear']))"/>
                 </oaf:dateAccepted>
                 <xsl:choose>
-
                     <xsl:when
                             test="//*[local-name() = 'rights'][starts-with(normalize-space(.), 'info:eu-repo/semantics')]">
                         <oaf:accessrights>
@@ -147,17 +126,12 @@
                         </xsl:choose>
                     </xsl:otherwise>
                 </xsl:choose>
-
                 <oaf:language>
-                    <xsl:value-of
+                    <xsl:value-of select="vocabulary:clean(//*[local-name()='language'], 'dnet:languages')"/>
-                            select="vocabulary:clean(//*[local-name()='language'], 'dnet:languages')"/>
                 </oaf:language>
-
-
                 <xsl:for-each
                         select="//*[local-name()='nameIdentifier'][contains(., 'info:eu-repo/grantAgreement/')], //*[local-name()='fundingReference']/*[local-name()='awardNumber']">
                     <xsl:choose>
-
                         <xsl:when
                                 test="matches(normalize-space(.), '(info:eu-repo/grantagreement/ec/fp7/)(\d\d\d\d\d\d)(.*)', 'i') or ../*[local-name() = 'funderIdentifier' and . = '10.13039/100011102']">
                             <oaf:projectid>
@@ -308,13 +282,10 @@
                                         select="concat($varWT, replace(normalize-space(.), '(info:eu-repo/grantagreement/wt/.*?/)([^/]*)(/.*)?', '$2', 'i'))"/>
                             </oaf:projectid>
                         </xsl:when>
-
                     </xsl:choose>
                 </xsl:for-each>
-
                 <xsl:for-each select="//*[local-name()='relatedIdentifier']">
-                    <xsl:if
+                    <xsl:if test="starts-with(./text(), 'https://zenodo.org/communities/')">
-                            test="starts-with(./text(), 'https://zenodo.org/communities/')">
                         <oaf:concept>
                             <xsl:attribute name="id">
                                 <xsl:value-of select="./text()"/>
@@ -322,7 +293,6 @@
                         </oaf:concept>
                     </xsl:if>
                 </xsl:for-each>
-
                 <oaf:hostedBy>
                     <xsl:attribute name="name">
                         <xsl:value-of select="$varOfficialName"/>
@@ -343,24 +313,19 @@
             <xsl:copy-of select="//*[local-name() = 'about']"/>
         </record>
     </xsl:template>
-
     <xsl:template match="node()|@*">
         <xsl:copy>
             <xsl:apply-templates select="node()|@*"/>
         </xsl:copy>
     </xsl:template>
-
     <xsl:template match="//*[local-name() = 'metadata']//*[local-name() = 'resource']">
         <xsl:copy>
             <xsl:apply-templates select="node()|@*"/>
         </xsl:copy>
     </xsl:template>
-
     <xsl:template match="//*[local-name() = 'resource']/*[local-name()='alternateIdentifiers']">
         <xsl:element name="alternateIdentifiers" namespace="http://www.openarchives.org/OAI/2.0/">
-
             <xsl:copy-of select="./*"/>
-
             <xsl:if test="//*[local-name() = 'resource']/*[local-name()='identifier'][@identifierType='Handle']">
                 <xsl:element name="alternateIdentifier" namespace="http://www.openarchives.org/OAI/2.0/">
                     <xsl:attribute name="alternateIdentifierType">
@@ -370,7 +335,6 @@
                             select="concat('http://hdl.handle.net/', //*[local-name() = 'resource']/*[local-name()='identifier'])"/>
                 </xsl:element>
             </xsl:if>
-
             <xsl:if test="//*[local-name() = 'resource']/*[local-name()='identifier'][@identifierType='URN']">
                 <xsl:element name="alternateIdentifier" namespace="http://www.openarchives.org/OAI/2.0/">
                     <xsl:attribute name="alternateIdentifierType">
@@ -380,7 +344,6 @@
                             select="concat('http://nbn-resolving.org/', //*[local-name() = 'resource']/*[local-name()='identifier'])"/>
                 </xsl:element>
             </xsl:if>
-
             <xsl:if test="//*[local-name() = 'resource']/*[local-name()='identifier'][@identifierType='DOI']">
                 <xsl:element name="alternateIdentifier" namespace="http://www.openarchives.org/OAI/2.0/">
                     <xsl:attribute name="alternateIdentifierType">
@@ -390,11 +353,8 @@
                             select="concat('http://dx.doi.org/', //*[local-name() = 'resource']/*[local-name()='identifier'])"/>
                 </xsl:element>
             </xsl:if>
-
         </xsl:element>
-
     </xsl:template>
-
     <xsl:template match="//*[local-name() = 'resource']/*[local-name()='identifier']">
         <xsl:copy-of select="."/>
         <xsl:if test="not(//*[local-name() = 'resource']/*[local-name()='alternateIdentifiers'])">
@@ -404,8 +364,7 @@
                         <xsl:attribute name="alternateIdentifierType">
                             <xsl:value-of select="'URL'"/>
                         </xsl:attribute>
-                        <xsl:value-of
+                        <xsl:value-of select="concat('http://hdl.handle.net/', .)"/>
-                                select="concat('http://hdl.handle.net/', .)"/>
                     </xsl:element>
                 </xsl:if>
                 <xsl:if test=".[@identifierType='URN']">
@@ -413,8 +372,7 @@
                         <xsl:attribute name="alternateIdentifierType">
                             <xsl:value-of select="'URL'"/>
                         </xsl:attribute>
-                        <xsl:value-of
+                        <xsl:value-of select="concat('http://nbn-resolving.org/', .)"/>
-                                select="concat('http://nbn-resolving.org/', .)"/>
                     </xsl:element>
                 </xsl:if>
                 <xsl:if test=".[@identifierType='DOI']">
@@ -422,17 +380,12 @@
                         <xsl:attribute name="alternateIdentifierType">
                             <xsl:value-of select="'URL'"/>
                         </xsl:attribute>
-                        <xsl:value-of
+                        <xsl:value-of select="concat('http://dx.doi.org/', .)"/>
-                                select="concat('http://dx.doi.org/', .)"/>
                     </xsl:element>
                 </xsl:if>
-
             </xsl:element>
         </xsl:if>
-
     </xsl:template>
-
-
     <xsl:template match="//*[local-name() = 'header']">
         <xsl:copy>
             <xsl:apply-templates select="node()|@*"/>
@@ -441,5 +394,4 @@
             </xsl:element>
         </xsl:copy>
     </xsl:template>
-
 </xsl:stylesheet>