it.uniroma2.art.semanticturkey.changetracking.model.HistoryRepositories Maven / Gradle / Ivy
package it.uniroma2.art.semanticturkey.changetracking.model;
import static java.util.stream.Collectors.toList;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.Optional;
import java.util.stream.Stream;
import org.eclipse.rdf4j.common.exception.RDF4JException;
import org.eclipse.rdf4j.common.iteration.ConvertingIteration;
import org.eclipse.rdf4j.common.iteration.Iteration;
import org.eclipse.rdf4j.model.BNode;
import org.eclipse.rdf4j.model.IRI;
import org.eclipse.rdf4j.model.Literal;
import org.eclipse.rdf4j.model.Model;
import org.eclipse.rdf4j.model.Resource;
import org.eclipse.rdf4j.model.Statement;
import org.eclipse.rdf4j.model.Value;
import org.eclipse.rdf4j.model.ValueFactory;
import org.eclipse.rdf4j.model.impl.LinkedHashModel;
import org.eclipse.rdf4j.model.impl.SimpleValueFactory;
import org.eclipse.rdf4j.model.vocabulary.SESAME;
import org.eclipse.rdf4j.query.BindingSet;
import org.eclipse.rdf4j.query.GraphQuery;
import org.eclipse.rdf4j.query.GraphQueryResult;
import org.eclipse.rdf4j.query.QueryEvaluationException;
import org.eclipse.rdf4j.query.QueryResult;
import org.eclipse.rdf4j.query.QueryResults;
import org.eclipse.rdf4j.query.TupleQuery;
import org.eclipse.rdf4j.query.TupleQueryResult;
import org.eclipse.rdf4j.query.impl.SimpleDataset;
import org.eclipse.rdf4j.queryrender.RenderUtils;
import org.eclipse.rdf4j.repository.RepositoryConnection;
import org.eclipse.rdf4j.rio.ntriples.NTriplesUtil;
import it.uniroma2.art.semanticturkey.changetracking.vocabulary.CHANGELOG;
import it.uniroma2.art.semanticturkey.changetracking.vocabulary.CHANGETRACKER;
import it.uniroma2.art.semanticturkey.changetracking.vocabulary.PROV;
/**
* Utility class encapsulating common operations with connections to history repositories.
*
* @author Manuel Fiorelli
*/
public abstract class HistoryRepositories {
/**
* Return the tips of the MASTER branch in the connected history repository. This method throws an
* IllegalStateException, if more than one tip is found for MASTER.
*
* @param conn
* @param historyGraph
* @return
* @throws IllegalStateException
* @throws RDF4JException
*/
public static Optional getTip(RepositoryConnection conn, IRI historyGraph)
throws IllegalStateException, RDF4JException {
TupleQuery tipQuery = conn.prepareTupleQuery(
// @formatter:off
" PREFIX cl: \n" +
" SELECT ?tip \n" +
" WHERE { \n" +
" cl:MASTER cl:tip ?tip . \n" +
" FILTER(isIRI(?tip) || isBLANK(?tip)) \n" +
" } \n" +
" LIMIT 2 "
// @formatter:on
);
SimpleDataset dataset = new SimpleDataset();
dataset.addDefaultGraph(historyGraph);
tipQuery.setDataset(dataset);
tipQuery.setIncludeInferred(false);
List tipList;
try(TupleQueryResult tupleQueryResult = tipQuery.evaluate();
Stream bindingSetStream = QueryResults.stream(tupleQueryResult)) {
tipList = bindingSetStream.map(bs -> bs.getValue("tip"))
.map(Resource.class::cast).collect(toList());
}
int tipCount = tipList.size();
if (tipCount > 1) {
throw new IllegalStateException("MASTER has an ambiguous tip");
}
if (tipCount == 0) {
return Optional.empty();
} else {
return Optional.of(tipList.get(0));
}
}
/**
* Returns the statements additions associated with a commit
*
* @param conn
* @param commit
* @param historyGraph
* @return
*/
public static QueryResult getAddedStaments(RepositoryConnection conn, Resource commit,
IRI historyGraph) {
return getCommitStaments(conn, commit, CHANGELOG.ADDED_STATEMENT, historyGraph);
}
/**
* Returns the statements removals associated with a commit
*
* @param conn
* @param commit
* @param historyGraph
* @return
*/
public static QueryResult getRemovedStaments(RepositoryConnection conn, Resource commit,
IRI historyGraph) {
return getCommitStaments(conn, commit, CHANGELOG.REMOVED_STATEMENT, historyGraph);
}
/**
* Helper function returning the statements associated with a commit by a certain property. This function
* encapsulate the dereification of statements.
*
* @param conn
* @param commit
* @param statementPredicate
* @param historyGraph
* @return
*/
private static QueryResult getCommitStaments(RepositoryConnection conn, Resource commit,
IRI statementPredicate, IRI historyGraph) {
TupleQuery tipQuery = conn.prepareTupleQuery(
// @formatter:off
" PREFIX cl: \n" +
" PREFIX prov: \n" +
" SELECT ?s ?p ?o ?c \n" +
" WHERE { \n" +
" ?commit prov:generated ?modifiedTriples . \n" +
" ?modifiedTriples ?statementPredicate ?q . \n" +
" ?q cl:subject ?s . \n" +
" ?q cl:predicate ?p . \n" +
" ?q cl:object ?o . \n" +
" ?q cl:context ?c . \n" +
" } "
// @formatter:on
);
tipQuery.setBinding("statementPredicate", statementPredicate);
tipQuery.setBinding("commit", commit);
SimpleDataset dataset = new SimpleDataset();
dataset.addDefaultGraph(historyGraph);
tipQuery.setDataset(dataset);
tipQuery.setIncludeInferred(false);
return new TupleBinding2StatementIteration(tipQuery.evaluate());
}
public static Optional getParent(RepositoryConnection conn, Resource commit, IRI historyGraph) {
List parentList = QueryResults
.asList(conn.getStatements(commit, CHANGELOG.PARENT_COMMIT, null, historyGraph));
int parentSize = parentList.size();
if (parentSize > 1) {
throw new IllegalStateException(
"Commit " + NTriplesUtil.toNTriplesString(commit) + " has more than one parent");
}
return parentSize != 0 ? Optional.of((Resource) parentList.get(0).getObject()) : Optional.empty();
}
public static Model getCommitUserMetadata(RepositoryConnection supportRepoConn, IRI commit, IRI graph,
boolean rewriteCommit) {
GraphQuery describeQuery = supportRepoConn.prepareGraphQuery(
"describe " + RenderUtils.toSPARQL(commit) + " from " + RenderUtils.toSPARQL(graph));
describeQuery.setIncludeInferred(false);
LinkedHashModel metadataModel = new LinkedHashModel();
Map bnodeRewriting = new LinkedHashMap<>();
try (GraphQueryResult results = describeQuery.evaluate()) {
while (results.hasNext()) {
Statement statement = results.next();
if (statement.getPredicate().getNamespace().equals(CHANGELOG.NAMESPACE))
continue;
Value obj = statement.getObject();
if (obj instanceof IRI) {
if (((IRI) obj).getNamespace().equals(CHANGELOG.NAMESPACE) && !CHANGELOG.isNull(obj))
continue;
}
metadataModel
.add(cloneStatement(statement, SimpleValueFactory.getInstance(), bnodeRewriting));
}
}
metadataModel.remove(commit, PROV.STARTED_AT_TIME, null);
metadataModel.remove(commit, PROV.ENDED_AT_TIME, null);
metadataModel.remove(commit, PROV.GENERATED, null);
if (rewriteCommit) {
Iterator it = metadataModel.filter(commit, null, null).iterator();
Model rewrittenStatements = new LinkedHashModel();
while (it.hasNext()) {
Statement stmt = it.next();
it.remove();
rewrittenStatements.add(CHANGETRACKER.COMMIT_METADATA, stmt.getPredicate(), stmt.getObject());
}
metadataModel.addAll(rewrittenStatements);
}
return metadataModel;
}
public static IRI cloneValue(IRI input, ValueFactory vf,
/* @Nullable */ Map bnodeRewriting) {
return vf.createIRI(input.stringValue());
}
public static BNode cloneValue(BNode input, ValueFactory vf,
/* @Nullable */ Map bnodeRewriting) {
if (bnodeRewriting == null) {
return vf.createBNode(input.stringValue());
} else {
return bnodeRewriting.computeIfAbsent(input, i -> vf.createBNode());
}
}
public static Resource cloneValue(Resource input, ValueFactory vf,
/* @Nullable */ Map bnodeRewriting) {
if (input instanceof IRI) {
return cloneValue((IRI) input, vf, bnodeRewriting);
} else {
return cloneValue((BNode) input, vf, bnodeRewriting);
}
}
public static Literal cloneValue(Literal input, ValueFactory vf,
/* @Nullable */ Map bnodeRewriting) {
if (input.getLanguage().isPresent()) {
return vf.createLiteral(input.getLabel(), input.getLanguage().get());
} else {
return vf.createLiteral(input.getLabel(), vf.createIRI(input.getDatatype().stringValue()));
}
}
public static Value cloneValue(Value input, ValueFactory vf,
/* @Nullable */ Map bnodeRewriting) {
if (input instanceof Resource) {
return cloneValue((Resource) input, vf, bnodeRewriting);
} else {
return cloneValue((Literal) input, vf, bnodeRewriting);
}
}
public static Statement cloneStatement(Statement stmt, ValueFactory vf,
/* @Nullable */ Map bnodeRewriting) {
return vf.createStatement(cloneValue(stmt.getSubject(), vf, bnodeRewriting),
cloneValue(stmt.getPredicate(), vf, bnodeRewriting),
cloneValue(stmt.getObject(), vf, bnodeRewriting),
stmt.getContext() != null ? cloneValue(stmt.getContext(), vf, bnodeRewriting) : null);
}
}
class TupleBinding2StatementIteration
extends ConvertingIteration
implements QueryResult {
private final ValueFactory vf;
public TupleBinding2StatementIteration(
Iteration iter) {
super(iter);
vf = SimpleValueFactory.getInstance();
}
@Override
protected Statement convert(BindingSet sourceObject) throws QueryEvaluationException {
Resource subject = (Resource) Objects.requireNonNull(sourceObject.getValue("s"),
"variable ?s may not be null");
IRI predicate = (IRI) Objects.requireNonNull(sourceObject.getValue("p"),
"variable ?p may not be null");
Value object = Objects.requireNonNull(sourceObject.getValue("o"), "variable ?o may not be null");
Resource context = (Resource) Objects.requireNonNull(sourceObject.getValue("c"),
"variable ?c may not be null");
if (CHANGELOG.isNull(context)) {
context = null;
}
return vf.createStatement(HistoryRepositories.cloneValue(subject, vf, null),
HistoryRepositories.cloneValue(predicate, vf, null),
HistoryRepositories.cloneValue(object, vf, null),
context != null ? HistoryRepositories.cloneValue(context, vf, null) : null);
}
}
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