joining entities using T x R x S method with groupByKey

dhp-schemas/pom.xml

@@ -5,7 +5,7 @@
     <parent>
         <groupId>eu.dnetlib.dhp</groupId>
         <artifactId>dhp</artifactId>
-        <version>1.1.5-SNAPSHOT</version>
+        <version>1.0.5-SNAPSHOT</version>
         <relativePath>../</relativePath>
     </parent>
 

dhp-schemas/src/main/java/eu/dnetlib/dhp/schema/dli/Entity.java

@@ -1,118 +0,0 @@
-package eu.dnetlib.dhp.schema.dli;
-
-import java.io.Serializable;
-import java.util.List;
-
-public class Entity implements Serializable {
-
-    private String identifier;
-
-    private List<Pid> pid;
-
-    private List<String> title;
-
-    private List<String> date;
-
-    private String typology;
-
-    private List<String> authors;
-
-    private List<Subject> subject;
-
-    private String description;
-
-    private String completionStatus;
-
-    private List<Provenance> collectedFrom;
-
-    private List<String> publisher;
-
-
-    public String getIdentifier() {
-        return identifier;
-    }
-
-    public void setIdentifier(String identifier) {
-        this.identifier = identifier;
-    }
-
-    public List<Pid> getPid() {
-        return pid;
-    }
-
-    public void setPid(List<Pid> pid) {
-        this.pid = pid;
-    }
-
-    public List<String> getTitle() {
-        return title;
-    }
-
-    public void setTitle(List<String> title) {
-        this.title = title;
-    }
-
-    public List<String> getDate() {
-        return date;
-    }
-
-    public void setDate(List<String> date) {
-        this.date = date;
-    }
-
-    public String getTypology() {
-        return typology;
-    }
-
-    public void setTypology(String typology) {
-        this.typology = typology;
-    }
-
-    public List<String> getAuthors() {
-        return authors;
-    }
-
-    public void setAuthors(List<String> authors) {
-        this.authors = authors;
-    }
-
-    public List<Subject> getSubject() {
-        return subject;
-    }
-
-    public void setSubject(List<Subject> subject) {
-        this.subject = subject;
-    }
-
-    public String getDescription() {
-        return description;
-    }
-
-    public void setDescription(String description) {
-        this.description = description;
-    }
-
-    public List<Provenance> getCollectedFrom() {
-        return collectedFrom;
-    }
-
-    public void setCollectedFrom(List<Provenance> collectedFrom) {
-        this.collectedFrom = collectedFrom;
-    }
-
-    public List<String> getPublisher() {
-        return publisher;
-    }
-
-    public void setPublisher(List<String> publisher) {
-        this.publisher = publisher;
-    }
-
-    public String getCompletionStatus() {
-        return completionStatus;
-    }
-
-    public void setCompletionStatus(String completionStatus) {
-        this.completionStatus = completionStatus;
-    }
-}

dhp-schemas/src/main/java/eu/dnetlib/dhp/schema/dli/Pid.java

@@ -1,33 +0,0 @@
-package eu.dnetlib.dhp.schema.dli;
-
-import eu.dnetlib.dhp.utils.DHPUtils;
-import org.apache.commons.lang3.StringUtils;
-
-public class Pid {
-
-    private String pid;
-
-    private String pidType;
-
-    public String getPid() {
-        return pid;
-    }
-
-    public void setPid(String pid) {
-        this.pid = pid;
-    }
-
-    public String getPidType() {
-        return pidType;
-    }
-
-    public void setPidType(String pidType) {
-        this.pidType = pidType;
-    }
-
-    public String generateId() {
-        if(StringUtils.isEmpty(pid) || StringUtils.isEmpty(pidType))
-            return null;
-        return DHPUtils.md5(String.format("%s::%s", pid, pidType));
-    }
-}

dhp-schemas/src/main/java/eu/dnetlib/dhp/schema/dli/Provenance.java

@@ -1,35 +0,0 @@
-package eu.dnetlib.dhp.schema.dli;
-
-public class Provenance {
-
-    private String datasourceId;
-
-    private String datasourceName;
-
-    private String completionStatus;
-
-
-    public String getDatasourceId() {
-        return datasourceId;
-    }
-
-    public void setDatasourceId(String datasourceId) {
-        this.datasourceId = datasourceId;
-    }
-
-    public String getDatasourceName() {
-        return datasourceName;
-    }
-
-    public void setDatasourceName(String datasourceName) {
-        this.datasourceName = datasourceName;
-    }
-
-    public String getCompletionStatus() {
-        return completionStatus;
-    }
-
-    public void setCompletionStatus(String completionStatus) {
-        this.completionStatus = completionStatus;
-    }
-}

dhp-schemas/src/main/java/eu/dnetlib/dhp/schema/dli/Relation.java

@@ -1,47 +0,0 @@
-package eu.dnetlib.dhp.schema.dli;
-
-import java.io.Serializable;
-import java.util.List;
-
-public class Relation implements Serializable {
-
-    private String source;
-
-    private String target;
-
-    private List<Provenance> provenance;
-
-    private RelationSemantic semantic;
-
-    public String getSource() {
-        return source;
-    }
-
-    public void setSource(String source) {
-        this.source = source;
-    }
-
-    public String getTarget() {
-        return target;
-    }
-
-    public void setTarget(String target) {
-        this.target = target;
-    }
-
-    public List<Provenance> getProvenance() {
-        return provenance;
-    }
-
-    public void setProvenance(List<Provenance> provenance) {
-        this.provenance = provenance;
-    }
-
-    public RelationSemantic getSemantic() {
-        return semantic;
-    }
-
-    public void setSemantic(RelationSemantic semantic) {
-        this.semantic = semantic;
-    }
-}

dhp-schemas/src/main/java/eu/dnetlib/dhp/schema/dli/RelationSemantic.java

@@ -1,16 +0,0 @@
-package eu.dnetlib.dhp.schema.dli;
-
-import java.io.Serializable;
-
-public class RelationSemantic extends Subject implements Serializable {
-
-    public String inverse;
-
-    public String getInverse() {
-        return inverse;
-    }
-
-    public void setInverse(String inverse) {
-        this.inverse = inverse;
-    }
-}

dhp-schemas/src/main/java/eu/dnetlib/dhp/schema/dli/Subject.java

@@ -1,35 +0,0 @@
-package eu.dnetlib.dhp.schema.dli;
-
-import java.io.Serializable;
-
-public class Subject implements Serializable {
-
-    private String schema;
-
-    private String value;
-
-    public Subject() {
-
-    }
-
-    public Subject(String schema, String value) {
-        this.schema = schema;
-        this.value = value;
-    }
-
-    public String getSchema() {
-        return schema;
-    }
-
-    public void setSchema(String schema) {
-        this.schema = schema;
-    }
-
-    public String getValue() {
-        return value;
-    }
-
-    public void setValue(String value) {
-        this.value = value;
-    }
-}

dhp-workflows/dhp-graph-provision/job-override.properties

@@ -1,5 +1,4 @@
 sparkDriverMemory=7G
 sparkExecutorMemory=7G
-sparkExecutorMemoryOverhead=5G
 hive_db_name=claudio
 sourcePath=/tmp/db_openaireplus_services_beta.export.2019.11.06

dhp-workflows/dhp-graph-provision/pom.xml

@@ -19,6 +19,10 @@
             <groupId>org.apache.spark</groupId>
             <artifactId>spark-sql_2.11</artifactId>
         </dependency>
+        <dependency>
+            <groupId>com.jayway.jsonpath</groupId>
+            <artifactId>json-path</artifactId>
+        </dependency>
 
         <dependency>
             <groupId>eu.dnetlib.dhp</groupId>

dhp-workflows/dhp-graph-provision/src/main/java/eu/dnetlib/dhp/graph/EntityNode.java

@@ -1,4 +0,0 @@
-package eu.dnetlib.dhp.graph;
-
-public class EntityNode {
-}

dhp-workflows/dhp-graph-provision/src/main/java/eu/dnetlib/dhp/graph/EntityRelEntity.java

@@ -1,20 +1,30 @@
 package eu.dnetlib.dhp.graph;
 
-import com.fasterxml.jackson.core.JsonProcessingException;
-import com.fasterxml.jackson.databind.ObjectMapper;
-import eu.dnetlib.dhp.schema.oaf.Relation;
-
 import java.io.Serializable;
 
 public class EntityRelEntity implements Serializable {
     private TypedRow source;
-    private Relation relation;
+    private TypedRow relation;
     private TypedRow target;
 
+    public EntityRelEntity() {
+    }
+
     public EntityRelEntity(TypedRow source) {
         this.source = source;
     }
 
+
+    //helpers
+    public Boolean hasMainEntity() {
+        return getSource() != null & getRelation() == null & getTarget() == null;
+    }
+
+    public Boolean hasRelatedEntity() {
+        return getSource() == null & getRelation() != null & getTarget() != null;
+    }
+
+
     public TypedRow getSource() {
         return source;
     }
@@ -24,11 +34,11 @@ public class EntityRelEntity implements Serializable {
         return this;
     }
 
-    public Relation getRelation() {
+    public TypedRow getRelation() {
         return relation;
     }
 
-    public EntityRelEntity setRelation(Relation relation) {
+    public EntityRelEntity setRelation(TypedRow relation) {
         this.relation = relation;
         return this;
     }
@@ -42,12 +52,4 @@ public class EntityRelEntity implements Serializable {
         return this;
     }
 
-    @Override
-    public String toString() {
-        try {
-            return new ObjectMapper().writeValueAsString(this);
-        } catch (JsonProcessingException e) {
-            throw new RuntimeException(e);
-        }
-    }
 }

dhp-workflows/dhp-graph-provision/src/main/java/eu/dnetlib/dhp/graph/GraphJoiner.java

@@ -1,139 +1,119 @@
 package eu.dnetlib.dhp.graph;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
-import eu.dnetlib.dhp.schema.oaf.*;
+import com.google.common.collect.Iterables;
+import com.google.common.collect.Lists;
+import com.jayway.jsonpath.JsonPath;
 import org.apache.hadoop.io.Text;
+import org.apache.hadoop.io.compress.GzipCodec;
 import org.apache.spark.api.java.JavaPairRDD;
 import org.apache.spark.api.java.JavaRDD;
 import org.apache.spark.api.java.JavaSparkContext;
-import org.apache.spark.api.java.Optional;
 import org.apache.spark.api.java.function.PairFunction;
-import org.apache.spark.sql.Encoders;
-import org.apache.spark.sql.SaveMode;
 import org.apache.spark.sql.SparkSession;
 import scala.Tuple2;
 
 import java.io.Serializable;
+import java.util.List;
 
 public class GraphJoiner implements Serializable {
 
-    public static final int MAX_RELS = 100;
+    public static final int MAX_RELS = 10;
 
     public void join(final SparkSession spark, final String inputPath, final String hiveDbName, final String outPath) {
 
         final JavaSparkContext sc = new JavaSparkContext(spark.sparkContext());
 
-        /*
+        final String entityIdPath = "$.id";
-        JavaPairRDD<String, TypedRow> entities = sc.sequenceFile(inputPath + "/publication", Text.class, Text.class)
-                .map(item -> new ObjectMapper().readValue(item._2().toString(), Publication.class))
-                .map(oaf -> new TypedRow("publication", oaf))
-                .mapToPair(toPair());
 
-         */
+        JavaPairRDD<String, TypedRow> datasource = readPathEntity(sc, entityIdPath, inputPath, "datasource");
+        JavaPairRDD<String, TypedRow> organization = readPathEntity(sc, entityIdPath, inputPath, "organization");
+        JavaPairRDD<String, TypedRow> project = readPathEntity(sc, entityIdPath, inputPath, "project");
+        JavaPairRDD<String, TypedRow> dataset = readPathEntity(sc, entityIdPath, inputPath, "dataset");
+        JavaPairRDD<String, TypedRow> otherresearchproduct = readPathEntity(sc, entityIdPath, inputPath, "otherresearchproduct");
+        JavaPairRDD<String, TypedRow> software = readPathEntity(sc, entityIdPath, inputPath, "software");
+        JavaPairRDD<String, TypedRow> publication = readPathEntity(sc, entityIdPath, inputPath, "publication");
 
-        JavaPairRDD<String, TypedRow> entities = sc.sequenceFile(inputPath + "/datasource", Text.class, Text.class)
+        final String entitiesPath = outPath + "/entities";
-                .map(item -> new ObjectMapper().readValue(item._2().toString(), Datasource.class))
+        datasource
-                .map(oaf -> new TypedRow("datasource", oaf))
+                .union(organization)
-                .mapToPair(toPair())
+                .union(project)
-            .union(sc.sequenceFile(inputPath + "/organization", Text.class, Text.class)
+                .union(dataset)
-                    .map(item -> new ObjectMapper().readValue(item._2().toString(), Organization.class))
+                .union(otherresearchproduct)
-                    .map(oaf -> new TypedRow("organization", oaf))
+                .union(software)
-                    .mapToPair(toPair()))
+                .union(publication)
-            .union(sc.sequenceFile(inputPath + "/project", Text.class, Text.class)
+                .map(e -> new EntityRelEntity().setSource(e._2()))
-                    .map(item -> new ObjectMapper().readValue(item._2().toString(), Project.class))
+                .map(e -> new ObjectMapper().writeValueAsString(e))
-                    .map(oaf -> new TypedRow("project", oaf))
+                .saveAsTextFile(entitiesPath, GzipCodec.class);
-                    .mapToPair(toPair()))
-            .union(sc.sequenceFile(inputPath + "/dataset", Text.class, Text.class)
-                    .map(item -> new ObjectMapper().readValue(item._2().toString(), Dataset.class))
-                    .map(oaf -> new TypedRow("dataset", oaf))
-                    .mapToPair(toPair()))
-            .union(sc.sequenceFile(inputPath + "/otherresearchproduct", Text.class, Text.class)
-                    .map(item -> new ObjectMapper().readValue(item._2().toString(), OtherResearchProduct.class))
-                    .map(oaf -> new TypedRow("otherresearchproduct", oaf))
-                    .mapToPair(toPair()))
-            .union(sc.sequenceFile(inputPath + "/software", Text.class, Text.class)
-                    .map(item -> new ObjectMapper().readValue(item._2().toString(), Software.class))
-                    .map(oaf -> new TypedRow("software", oaf))
-                    .mapToPair(toPair()));
-                /*
-            .union(sc.sequenceFile(inputPath + "/publication", Text.class, Text.class)
-                    .map(item -> new ObjectMapper().readValue(item._2().toString(), Publication.class))
-                    .map(oaf -> new TypedRow("publication", oaf))
-                    .mapToPair(toPair()));
 
-         */
+        JavaPairRDD<String, EntityRelEntity> entities = sc.textFile(entitiesPath)
+                .map(t -> new ObjectMapper().readValue(t, EntityRelEntity.class))
+                .mapToPair(t -> new Tuple2<>(t.getSource().getSource(), t));
 
-        /*
+        final JavaPairRDD<String, EntityRelEntity> relation = readPathRelation(sc, inputPath)
-        JavaRDD<Relation> rels = sc.sequenceFile(inputPath + "/relation", Text.class, Text.class)
+                .map(p -> new EntityRelEntity().setRelation(p))
-                .map(item -> new ObjectMapper().readValue(item._2().toString(), Relation.class))
+                .mapToPair(p -> new Tuple2<>(p.getRelation().getSource(), p))
-                .map(oaf -> new TypedRow("relation", oaf))
-                .mapToPair(toPair())
                 .groupByKey()
-                .map(t -> Iterables.limit(t._2(), MAX_RELS))
+                .map(p -> Iterables.limit(p._2(), MAX_RELS))
-                .flatMap(t -> t.iterator())
+                .flatMap(p -> p.iterator())
-                .map(t -> (Relation) t.getOaf());
+                .mapToPair(p -> new Tuple2<>(p.getRelation().getTarget(), p));
 
-        spark.createDataset(rels.rdd(), Encoders.bean(Relation.class))
+        final String joinByTargetPath = outPath + "/join_by_target";
-                .write()
+        relation.join(entities)
-                .mode(SaveMode.Overwrite)
+                .map(s -> new EntityRelEntity()
-                .saveAsTable(hiveDbName + ".relation_100");
+                        .setRelation(s._2()._1().getRelation())
-        */
+                        .setTarget(s._2()._2().getSource()))
+                .map(e -> new ObjectMapper().writeValueAsString(e))
+                .saveAsTextFile(joinByTargetPath, GzipCodec.class);
 
-        JavaPairRDD<String, TypedRow> bounded_rels = spark.table(hiveDbName + ".relation_" + MAX_RELS)
-                .as(Encoders.bean(Relation.class))
-                .javaRDD()
-                .map(r -> new TypedRow("relation", r))
-                .mapToPair(toPair());
 
-        // build the adjacency list: e -> r
+        JavaPairRDD<String, EntityRelEntity> bySource = sc.textFile(joinByTargetPath)
-        JavaPairRDD<String, Tuple2<TypedRow, Optional<TypedRow>>> adjacency_list = entities.leftOuterJoin(bounded_rels);
+                .map(t -> new ObjectMapper().readValue(t, EntityRelEntity.class))
+                .mapToPair(t -> new Tuple2<>(t.getRelation().getSource(), t));
 
-        JavaRDD<EntityRelEntity> linked_entities = adjacency_list
+        entities
-                .mapToPair(toPairTarget())          // make rel.targetid explicit so that we can join it
+                .union(bySource)
-                .leftOuterJoin(entities)            // again with the entities to get the target entity
+                .groupByKey()   // by source id
-                .map(l -> toEntityRelEntity(l));    // and map it to a more readable representation
+                .map(p -> {
-
+                    final LinkedEntity e = new LinkedEntity();
-        spark.createDataFrame(linked_entities, EntityRelEntity.class)
+                    final List<Tuple> links = Lists.newArrayList();
-                .write()
+                    for(EntityRelEntity rel : p._2()) {
-                .mode(SaveMode.Overwrite)
+                        if (rel.hasMainEntity() & e.getEntity() == null) {
-                .saveAsTable(hiveDbName + ".linked_entities");
+                            e.setEntity(rel.getSource());
+                        }
+                        if (rel.hasRelatedEntity()) {
+                            links.add(new Tuple()
+                                    .setRelation(rel.getRelation())
+                                    .setTarget(rel.getTarget()));
+                        }
+                    }
+                    e.setLinks(links);
+                    if (e.getEntity() == null) {
+                        throw new IllegalStateException("missing main entity on '" + p._1() + "'");
+                    }
+                    return e;
+                })
+                .map(e -> new ObjectMapper().writeValueAsString(e))
+                .saveAsTextFile(outPath + "/linked_entities", GzipCodec.class);
      }
 
-    private EntityRelEntity toEntityRelEntity(Tuple2<String, Tuple2<Tuple2<String, Tuple2<TypedRow, Optional<TypedRow>>>, Optional<TypedRow>>> l) {
+    private JavaPairRDD<String, TypedRow> readPathEntity(final JavaSparkContext sc, final String idPath, final String inputPath, final String type) {
-        // extract the entity source
+        return sc.sequenceFile(inputPath + "/" + type, Text.class, Text.class)
-        final EntityRelEntity res = new EntityRelEntity(l._2()._1()._2()._1());
+                .mapToPair((PairFunction<Tuple2<Text, Text>, String, TypedRow>) item -> {
-
+                    final String json = item._2().toString();
-        if(l._2()._1()._2()._2().isPresent() && l._2()._2().isPresent()) {
+                    final String id = JsonPath.read(json, idPath);
-
+                    return new Tuple2<>(id, new TypedRow(id, type, json));
-            // extract the relationship
+                });
-            res.setRelation((Relation) l._2()._1()._2()._2().get().getOaf());
-
-            // extract the related entity
-            res.setTarget(l._2()._2().get());
-        }
-
-        return res;
     }
 
-    private PairFunction<Tuple2<String, Tuple2<TypedRow, Optional<TypedRow>>>, String, Tuple2<String, Tuple2<TypedRow, Optional<TypedRow>>>> toPairTarget() {
+    private JavaRDD<TypedRow> readPathRelation(final JavaSparkContext sc, final String inputPath) {
-        return e -> {
+        return sc.sequenceFile(inputPath + "/relation", Text.class, Text.class)
-            Optional<TypedRow> o = e._2()._2();
+                .map(item -> {
-            if (o.isPresent()) {
+                    final String json = item._2().toString();
-                return new Tuple2<>(((Relation) o.get().getOaf()).getTarget(), e);
+                    final String source = JsonPath.read(json, "$.source");
-            } else {
+                    final String target = JsonPath.read(json, "$.target");
-                return new Tuple2<>(null, e);
+                    return new TypedRow(source, target, "relation", json);
-            }
+                });
-        };
-    }
-
-    private PairFunction<TypedRow, String, TypedRow> toPair() {
-        return e -> {
-            if (!"relation".equals(e.getType())) {
-                return new Tuple2<>( ((OafEntity) e.getOaf()).getId(), e);
-            } else {
-                return new Tuple2<>( ((Relation) e.getOaf()).getSource(), e);
-            }
-        };
     }
 
 }

dhp-workflows/dhp-graph-provision/src/main/java/eu/dnetlib/dhp/graph/LinkedEntity.java

@@ -0,0 +1,29 @@
+package eu.dnetlib.dhp.graph;
+
+import java.io.Serializable;
+import java.util.List;
+
+public class LinkedEntity implements Serializable {
+
+    private TypedRow entity;
+
+    private List<Tuple> links;
+
+    public TypedRow getEntity() {
+        return entity;
+    }
+
+    public LinkedEntity setEntity(TypedRow entity) {
+        this.entity = entity;
+        return this;
+    }
+
+    public List<Tuple> getLinks() {
+        return links;
+    }
+
+    public LinkedEntity setLinks(List<Tuple> links) {
+        this.links = links;
+        return this;
+    }
+}

dhp-workflows/dhp-graph-provision/src/main/java/eu/dnetlib/dhp/graph/RelatedEntity.java

@@ -1,69 +0,0 @@
-package eu.dnetlib.dhp.graph;
-
-import java.io.Serializable;
-
-public class RelatedEntity implements Serializable {
-
-    private String relType;
-
-    private String subRelType;
-
-    private String relClass;
-
-    private String type;
-
-    private String payload;
-
-    public RelatedEntity(String relType, String subRelType, String relClass, String type, String payload) {
-        this.relType = relType;
-        this.subRelType = subRelType;
-        this.relClass = relClass;
-        this.type = type;
-        this.payload = payload;
-    }
-
-    public String getRelType() {
-        return relType;
-    }
-
-    public RelatedEntity setRelType(String relType) {
-        this.relType = relType;
-        return this;
-    }
-
-    public String getSubRelType() {
-        return subRelType;
-    }
-
-    public RelatedEntity setSubRelType(String subRelType) {
-        this.subRelType = subRelType;
-        return this;
-    }
-
-    public String getRelClass() {
-        return relClass;
-    }
-
-    public RelatedEntity setRelClass(String relClass) {
-        this.relClass = relClass;
-        return this;
-    }
-
-    public String getType() {
-        return type;
-    }
-
-    public RelatedEntity setType(String type) {
-        this.type = type;
-        return this;
-    }
-
-    public String getPayload() {
-        return payload;
-    }
-
-    public RelatedEntity setPayload(String payload) {
-        this.payload = payload;
-        return this;
-    }
-}

dhp-workflows/dhp-graph-provision/src/main/java/eu/dnetlib/dhp/graph/SparkGraphIndexingJob.java

@@ -4,21 +4,27 @@ import eu.dnetlib.dhp.application.ArgumentApplicationParser;
 import org.apache.commons.io.IOUtils;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
+import org.apache.spark.SparkConf;
 import org.apache.spark.sql.SparkSession;
 
 public class SparkGraphIndexingJob {
 
-    private final static String ENTITY_NODES_PATH = "/tmp/entity_node";
+    private final static String OUTPUT_BASE_PATH = "/tmp/openaire_provision";
 
     public static void main(String[] args) throws Exception {
 
         final ArgumentApplicationParser parser = new ArgumentApplicationParser(IOUtils.toString(SparkGraphIndexingJob.class.getResourceAsStream("/eu/dnetlib/dhp/graph/input_graph_parameters.json")));
         parser.parseArgument(args);
+
+        final SparkConf conf = new SparkConf()
+                .set("spark.serializer", "org.apache.spark.serializer.KryoSerializer")
+                .set("hive.metastore.uris", parser.get("hive_metastore_uris"));
+
         final SparkSession spark = SparkSession
                 .builder()
+                .config(conf)
                 .appName(SparkGraphIndexingJob.class.getSimpleName())
                 .master(parser.get("master"))
-                .config("hive.metastore.uris", parser.get("hive_metastore_uris"))
                 .enableHiveSupport()
                 .getOrCreate();
 
@@ -26,11 +32,12 @@ public class SparkGraphIndexingJob {
         final String hiveDbName = parser.get("hive_db_name");
 
         final FileSystem fs = FileSystem.get(spark.sparkContext().hadoopConfiguration());
-        if (fs.exists(new Path(ENTITY_NODES_PATH))) {
+        if (fs.exists(new Path(OUTPUT_BASE_PATH))) {
-            fs.delete(new Path(ENTITY_NODES_PATH), true);
+            fs.delete(new Path(OUTPUT_BASE_PATH), true);
+            fs.mkdirs(new Path(OUTPUT_BASE_PATH));
         }
 
-        new GraphJoiner().join(spark, inputPath, hiveDbName, ENTITY_NODES_PATH);
+        new GraphJoiner().join(spark, inputPath, hiveDbName, OUTPUT_BASE_PATH);
     }
 
 }

dhp-workflows/dhp-graph-provision/src/main/java/eu/dnetlib/dhp/graph/Tuple.java

@@ -0,0 +1,31 @@
+package eu.dnetlib.dhp.graph;
+
+import eu.dnetlib.dhp.schema.oaf.Oaf;
+import eu.dnetlib.dhp.schema.oaf.Relation;
+
+import java.io.Serializable;
+
+public class Tuple implements Serializable {
+
+    private TypedRow relation;
+
+    private TypedRow target;
+
+    public TypedRow getRelation() {
+        return relation;
+    }
+
+    public Tuple setRelation(TypedRow relation) {
+        this.relation = relation;
+        return this;
+    }
+
+    public TypedRow getTarget() {
+        return target;
+    }
+
+    public Tuple setTarget(TypedRow target) {
+        this.target = target;
+        return this;
+    }
+}

dhp-workflows/dhp-graph-provision/src/main/java/eu/dnetlib/dhp/graph/TypedRow.java

@@ -1,20 +1,46 @@
 package eu.dnetlib.dhp.graph;
 
-import com.fasterxml.jackson.core.JsonProcessingException;
-import com.fasterxml.jackson.databind.ObjectMapper;
-import eu.dnetlib.dhp.schema.oaf.Oaf;
-
 import java.io.Serializable;
 
 public class TypedRow implements Serializable {
-    private String type;
-    private Oaf oaf;
 
-    public TypedRow(String type, Oaf oaf) {
+    private String source;
+    private String target;
+    private String type;
+    private String oaf;
+
+    public TypedRow() {
+    }
+
+    public TypedRow(String source, String type, String oaf) {
+        this.source = source;
         this.type = type;
         this.oaf = oaf;
     }
 
+    public TypedRow(String source, String target, String type, String oaf) {
+        this(source, type, oaf);
+        this.target = target;
+    }
+
+    public String getSource() {
+        return source;
+    }
+
+    public TypedRow setSource(String source) {
+        this.source = source;
+        return this;
+    }
+
+    public String getTarget() {
+        return target;
+    }
+
+    public TypedRow setTarget(String target) {
+        this.target = target;
+        return this;
+    }
+
     public String getType() {
         return type;
     }
@@ -24,21 +50,13 @@ public class TypedRow implements Serializable {
         return this;
     }
 
-    public Oaf getOaf() {
+    public String getOaf() {
         return oaf;
     }
 
-    public TypedRow setOaf(Oaf oaf) {
+    public TypedRow setOaf(String oaf) {
         this.oaf = oaf;
         return this;
     }
 
-    @Override
-    public String toString() {
-        try {
-            return new ObjectMapper().writeValueAsString(this);
-        } catch (JsonProcessingException e) {
-            throw new RuntimeException(e);
-        }
-    }
 }

dhp-workflows/dhp-graph-provision/src/main/resources/eu/dnetlib/dhp/graph/oozie_app/config-default.xml

@@ -23,4 +23,12 @@
         <name>hive_db_name</name>
         <value>openaire</value>
     </property>
+    <property>
+        <name>spark2YarnHistoryServerAddress</name>
+        <value>http://iis-cdh5-test-gw.ocean.icm.edu.pl:18088</value>
+    </property>
+    <property>
+        <name>spark2EventLogDir</name>
+        <value>/user/spark/applicationHistory</value>
+    </property>
 </configuration>

dhp-workflows/dhp-graph-provision/src/main/resources/eu/dnetlib/dhp/graph/oozie_app/workflow.xml

@@ -16,6 +16,14 @@
             <name>sparkExecutorCores</name>
             <description>number of cores used by single executor</description>
         </property>
+        <property>
+            <name>spark2YarnHistoryServerAddress</name>
+            <description>spark 2.* yarn history server address</description>
+        </property>
+        <property>
+            <name>spark2EventLogDir</name>
+            <description>spark 2.* event log dir location</description>
+        </property>
     </parameters>
 
     <start to="GraphJoinEntities"/>
@@ -33,7 +41,16 @@
             <name>GraphIndexing</name>
             <class>eu.dnetlib.dhp.graph.SparkGraphIndexingJob</class>
             <jar>dhp-graph-provision-${projectVersion}.jar</jar>
-            <spark-opts>--executor-memory ${sparkExecutorMemory} --executor-cores ${sparkExecutorCores} --driver-memory=${sparkDriverMemory} --conf spark.extraListeners="com.cloudera.spark.lineage.NavigatorAppListener" --conf spark.sql.queryExecutionListeners="com.cloudera.spark.lineage.NavigatorQueryListener" --conf spark.sql.warehouse.dir="/user/hive/warehouse" --conf spark.yarn.executor.memoryOverhead=${sparkExecutorMemoryOverhead}</spark-opts>
+            <spark-opts>
+                --executor-memory ${sparkExecutorMemory}
+                --executor-cores ${sparkExecutorCores}
+                --driver-memory=${sparkDriverMemory}
+                --conf spark.extraListeners="com.cloudera.spark.lineage.NavigatorAppListener"
+                --conf spark.sql.queryExecutionListeners="com.cloudera.spark.lineage.NavigatorQueryListener"
+                --conf spark.sql.warehouse.dir="/user/hive/warehouse"
+                --conf spark.yarn.historyServer.address=${spark2YarnHistoryServerAddress}
+                --conf spark.eventLog.dir=${nameNode}${spark2EventLogDir}
+            </spark-opts>
             <arg>-mt</arg> <arg>yarn-cluster</arg>
             <arg>--sourcePath</arg><arg>${sourcePath}</arg>
             <arg>--hive_db_name</arg><arg>${hive_db_name}</arg>