dnet-hadoop/dhp-workflows/dhp-graph-provision/src/main/java/eu/dnetlib/dhp/oa/provision/PrepareRelationsJob.java

184 lines
7.2 KiB
Java

package eu.dnetlib.dhp.oa.provision;
import static eu.dnetlib.dhp.common.SparkSessionSupport.runWithSparkSession;
import java.util.HashSet;
import java.util.Optional;
import java.util.Set;
import org.apache.commons.io.IOUtils;
import org.apache.spark.SparkConf;
import org.apache.spark.api.java.JavaRDD;
import org.apache.spark.api.java.JavaSparkContext;
import org.apache.spark.rdd.RDD;
import org.apache.spark.sql.Encoders;
import org.apache.spark.sql.SaveMode;
import org.apache.spark.sql.SparkSession;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.google.common.base.Splitter;
import com.google.common.collect.Iterables;
import com.google.common.collect.Sets;
import eu.dnetlib.dhp.application.ArgumentApplicationParser;
import eu.dnetlib.dhp.common.HdfsSupport;
import eu.dnetlib.dhp.oa.provision.model.SortableRelationKey;
import eu.dnetlib.dhp.oa.provision.utils.RelationPartitioner;
import eu.dnetlib.dhp.schema.oaf.Relation;
import scala.Tuple2;
/**
* Joins the graph nodes by resolving the links of distance = 1 to create an adjacency list of linked objects. The
* operation considers all the entity types (publication, dataset, software, ORP, project, datasource, organization, and
* all the possible relationships (similarity links produced by the Dedup process are excluded).
* <p>
* The operation is implemented by sequentially joining one entity type at time (E) with the relationships (R), and
* again by E, finally grouped by E.id;
* <p>
* The workflow is organized in different parts aimed to to reduce the complexity of the operation 1)
* PrepareRelationsJob: only consider relationships that are not virtually deleted ($.dataInfo.deletedbyinference ==
* false), each entity can be linked at most to 100 other objects
* <p>
* 2) JoinRelationEntityByTargetJob: (phase 1): prepare tuples [relation - target entity] (R - T): for each entity type
* E_i map E_i as RelatedEntity T_i to simplify the model and extracting only the necessary information join (R.target =
* T_i.id) save the tuples (R_i, T_i) (phase 2): create the union of all the entity types E, hash by id read the tuples
* (R, T), hash by R.source join E.id = (R, T).source, where E becomes the Source Entity S save the tuples (S, R, T)
* <p>
* 3) AdjacencyListBuilderJob: given the tuple (S - R - T) we need to group by S.id -> List [ R - T ], mapping the
* result as JoinedEntity
* <p>
* 4) XmlConverterJob: convert the JoinedEntities as XML records
*/
public class PrepareRelationsJob {
private static final Logger log = LoggerFactory.getLogger(PrepareRelationsJob.class);
private static final ObjectMapper OBJECT_MAPPER = new ObjectMapper();
public static final int MAX_RELS = 100;
public static final int DEFAULT_NUM_PARTITIONS = 3000;
public static void main(String[] args) throws Exception {
String jsonConfiguration = IOUtils
.toString(
PrepareRelationsJob.class
.getResourceAsStream(
"/eu/dnetlib/dhp/oa/provision/input_params_prepare_relations.json"));
final ArgumentApplicationParser parser = new ArgumentApplicationParser(jsonConfiguration);
parser.parseArgument(args);
Boolean isSparkSessionManaged = Optional
.ofNullable(parser.get("isSparkSessionManaged"))
.map(Boolean::valueOf)
.orElse(Boolean.TRUE);
log.info("isSparkSessionManaged: {}", isSparkSessionManaged);
String inputRelationsPath = parser.get("inputRelationsPath");
log.info("inputRelationsPath: {}", inputRelationsPath);
String outputPath = parser.get("outputPath");
log.info("outputPath: {}", outputPath);
int relPartitions = Optional
.ofNullable(parser.get("relPartitions"))
.map(Integer::valueOf)
.orElse(DEFAULT_NUM_PARTITIONS);
log.info("relPartitions: {}", relPartitions);
Set<String> relationFilter = Optional
.ofNullable(parser.get("relationFilter"))
.map(s -> Sets.newHashSet(Splitter.on(",").split(s)))
.orElse(new HashSet<>());
log.info("relationFilter: {}", relationFilter);
int maxRelations = Optional
.ofNullable(parser.get("maxRelations"))
.map(Integer::valueOf)
.orElse(MAX_RELS);
log.info("maxRelations: {}", maxRelations);
SparkConf conf = new SparkConf();
runWithSparkSession(
conf,
isSparkSessionManaged,
spark -> {
removeOutputDir(spark, outputPath);
prepareRelationsRDD(
spark, inputRelationsPath, outputPath, relationFilter, maxRelations, relPartitions);
});
}
/**
* RDD based implementation that prepares the graph relations by limiting the number of outgoing links and filtering
* the relation types according to the given criteria. Moreover, outgoing links kept within the given limit are
* prioritized according to the weights indicated in eu.dnetlib.dhp.oa.provision.model.SortableRelation.
*
* @param spark the spark session
* @param inputRelationsPath source path for the graph relations
* @param outputPath output path for the processed relations
* @param relationFilter set of relation filters applied to the `relClass` field
* @param maxRelations maximum number of allowed outgoing edges
* @param relPartitions number of partitions for the output RDD
*/
private static void prepareRelationsRDD(
SparkSession spark, String inputRelationsPath, String outputPath, Set<String> relationFilter, int maxRelations,
int relPartitions) {
// group by SOURCE and apply limit
RDD<Relation> bySource = readPathRelationRDD(spark, inputRelationsPath)
.filter(rel -> rel.getDataInfo().getDeletedbyinference() == false)
.filter(rel -> relationFilter.contains(rel.getRelClass()) == false)
.mapToPair(r -> new Tuple2<>(SortableRelationKey.create(r, r.getSource()), r))
.repartitionAndSortWithinPartitions(new RelationPartitioner(relPartitions))
.groupBy(Tuple2::_1)
.map(Tuple2::_2)
.map(t -> Iterables.limit(t, maxRelations))
.flatMap(Iterable::iterator)
.map(Tuple2::_2)
.rdd();
// group by TARGET and apply limit
RDD<Relation> byTarget = readPathRelationRDD(spark, inputRelationsPath)
.filter(rel -> rel.getDataInfo().getDeletedbyinference() == false)
.filter(rel -> relationFilter.contains(rel.getRelClass()) == false)
.mapToPair(r -> new Tuple2<>(SortableRelationKey.create(r, r.getTarget()), r))
.repartitionAndSortWithinPartitions(new RelationPartitioner(relPartitions))
.groupBy(Tuple2::_1)
.map(Tuple2::_2)
.map(t -> Iterables.limit(t, maxRelations))
.flatMap(Iterable::iterator)
.map(Tuple2::_2)
.rdd();
spark
.createDataset(bySource.union(byTarget), Encoders.bean(Relation.class))
.repartition(relPartitions)
.write()
.mode(SaveMode.Overwrite)
.parquet(outputPath);
}
/**
* Reads a JavaRDD of eu.dnetlib.dhp.oa.provision.model.SortableRelation objects from a newline delimited json text
* file,
*
* @param spark
* @param inputPath
* @return the JavaRDD<SortableRelation> containing all the relationships
*/
private static JavaRDD<Relation> readPathRelationRDD(
SparkSession spark, final String inputPath) {
JavaSparkContext sc = JavaSparkContext.fromSparkContext(spark.sparkContext());
return sc.textFile(inputPath).map(s -> OBJECT_MAPPER.readValue(s, Relation.class));
}
private static void removeOutputDir(SparkSession spark, String path) {
HdfsSupport.remove(path, spark.sparkContext().hadoopConfiguration());
}
}