package com.cedarsoft.serialization.neo4j.test.utils;
import org.junit.rules.*;
import org.junit.runner.*;
import org.junit.runners.model.*;
import org.neo4j.cypher.javacompat.ExecutionEngine;
import org.neo4j.cypher.javacompat.ExecutionResult;
import org.neo4j.graphdb.GraphDatabaseService;
import org.neo4j.graphdb.Transaction;
import org.neo4j.test.TestGraphDatabaseFactory;
import javax.annotation.Nonnull;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
/**
* Rule that provides neo4j databases
* @author Johannes Schneider (<a href="mailto:js@cedarsoft.com">js@cedarsoft.com</a>)
*/
public class Neo4jRule implements TestRule {
@Nonnull
private final TemporaryFolder tmp = new TemporaryFolder();
@Override
public Statement apply( final Statement base, Description description ) {
return tmp.apply( new Statement() {
@Override
public void evaluate() throws Throwable {
GraphDatabaseService db = createDb();
try {
base.evaluate();
} catch ( Throwable e ) {
dump(db);
throw e;
} finally {
after();
}
}
}, description );
}
public static void dump( @Nonnull GraphDatabaseService db ) {
if ( "true".equalsIgnoreCase( System.getProperty( "neo4j.dumpOnError" ) ) ) {
try {
System.err.println( dumpToText(db) );
Graphviz.toPng( db );
} catch ( Exception e ) {
e.printStackTrace();
}
}
}
@Nonnull
public static String dumpToText( @Nonnull GraphDatabaseService db ) {
try ( Transaction tx = db.beginTx() ) {
ExecutionResult result = new ExecutionEngine( db ).execute( "MATCH (n)\n" + "RETURN n;" );
return result.dumpToString();
}
}
@Nonnull
private final List<GraphDatabaseService> dbs = new ArrayList<>();
@Nonnull
public GraphDatabaseService createDb() throws IOException {
GraphDatabaseService db = new TestGraphDatabaseFactory().newImpermanentDatabase( tmp.newFolder().getAbsolutePath() );
dbs.add( db );
return db;
}
private void after() {
for ( GraphDatabaseService db : dbs ) {
db.shutdown();
}
}
@Nonnull
@Deprecated
public GraphDatabaseService getGraphDb() throws IOException {
return createDb();
}
}