overflowdb.tinkerpop.TinkerIoRegistryV2d0 Maven / Gradle / Ivy
package overflowdb.tinkerpop;
import org.apache.tinkerpop.gremlin.structure.Edge;
import org.apache.tinkerpop.gremlin.structure.Vertex;
import org.apache.tinkerpop.gremlin.structure.io.AbstractIoRegistry;
import org.apache.tinkerpop.gremlin.structure.io.IoRegistry;
import org.apache.tinkerpop.gremlin.structure.io.graphson.GraphSONIo;
import org.apache.tinkerpop.gremlin.structure.io.graphson.GraphSONTokens;
import org.apache.tinkerpop.gremlin.structure.io.graphson.TinkerPopJacksonModule;
import org.apache.tinkerpop.gremlin.structure.io.gryo.GryoIo;
import org.apache.tinkerpop.gremlin.structure.io.gryo.GryoWriter;
import org.apache.tinkerpop.shaded.jackson.core.JsonGenerator;
import org.apache.tinkerpop.shaded.jackson.core.JsonParser;
import org.apache.tinkerpop.shaded.jackson.core.JsonProcessingException;
import org.apache.tinkerpop.shaded.jackson.databind.DeserializationContext;
import org.apache.tinkerpop.shaded.jackson.databind.SerializerProvider;
import org.apache.tinkerpop.shaded.jackson.databind.deser.std.StdDeserializer;
import org.apache.tinkerpop.shaded.jackson.databind.ser.std.StdScalarSerializer;
import org.apache.tinkerpop.shaded.kryo.Kryo;
import org.apache.tinkerpop.shaded.kryo.Serializer;
import org.apache.tinkerpop.shaded.kryo.io.Input;
import org.apache.tinkerpop.shaded.kryo.io.Output;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
/**
* An implementation of the {@link IoRegistry} interface that provides serializers with custom configurations for
* implementation specific classes that might need to be serialized. This registry allows a {@link OdbGraphTp3} to
* be serialized directly which is useful for moving small graphs around on the network.
* Most providers need not implement this kind of custom serializer as they will deal with much larger graphs that
* wouldn't be practical to serialize in this fashion. This is a bit of a special case for OverflowDb given its
* in-memory status. Typical implementations would create serializers for a complex vertex identifier or a
* custom data class like a "geographic point".
*
* @author Stephen Mallette (http://stephen.genoprime.com)
*/
public final class TinkerIoRegistryV2d0 extends AbstractIoRegistry {
private static final TinkerIoRegistryV2d0 INSTANCE = new TinkerIoRegistryV2d0();
private TinkerIoRegistryV2d0() {
register(GryoIo.class, OdbGraphTp3.class, new GryoSerializer());
register(GraphSONIo.class, null, new TinkerModuleV2d0());
}
public static TinkerIoRegistryV2d0 instance() {
return INSTANCE;
}
/**
* Provides a method to serialize an entire {@link OdbGraphTp3} into itself for Gryo. This is useful when
* shipping small graphs around through Gremlin Server. Reuses the existing Kryo instance for serialization.
*/
final static class GryoSerializer extends Serializer {
@Override
public void write(final Kryo kryo, final Output output, final OdbGraphTp3 graph) {
try (final ByteArrayOutputStream stream = new ByteArrayOutputStream()) {
GryoWriter.build().mapper(() -> kryo).create().writeGraph(stream, graph);
final byte[] bytes = stream.toByteArray();
output.writeInt(bytes.length);
output.write(bytes);
} catch (Exception io) {
throw new RuntimeException(io);
}
}
@Override
public OdbGraphTp3 read(final Kryo kryo, final Input input, final Class clazz) {
throw new UnsupportedOperationException();
// final Configuration conf = new BaseConfiguration();
// conf.setProperty("gremlin.tinkergraph.defaultVertexPropertyCardinality", "list");
// final OdbGraphTp3 graph = OdbGraphTp3.open(conf);
// final int len = input.readInt();
// final byte[] bytes = input.readBytes(len);
// try (final ByteArrayInputStream stream = new ByteArrayInputStream(bytes)) {
// GryoReader.build().mapper(() -> kryo).create().readGraph(stream, graph);
// } catch (Exception io) {
// throw new RuntimeException(io);
// }
//
// return graph;
}
}
/**
* Provides a method to serialize an entire {@link OdbGraphTp3} into itself for GraphSON. This is useful when
* shipping small graphs around through Gremlin Server.
*/
final static class TinkerModuleV2d0 extends TinkerPopJacksonModule {
public TinkerModuleV2d0() {
super("tinkergraph-2.0");
addSerializer(OdbGraphTp3.class, new JacksonSerializer());
addDeserializer(OdbGraphTp3.class, new JacksonDeserializer());
}
@Override
public Map getTypeDefinitions() {
return new HashMap() {{
put(OdbGraphTp3.class, "graph");
}};
}
@Override
public String getTypeNamespace() {
return "tinker";
}
}
/**
* Serializes the graph into an edge list format. Edge list is a better choices than adjacency list (which is
* typically standard from the {@link org.apache.tinkerpop.gremlin.structure.io.GraphReader} and {@link org.apache.tinkerpop.gremlin.structure.io.GraphWriter} perspective) in this case because
* the use case for this isn't around massive graphs. The use case is for "small" subgraphs that are being
* shipped over the wire from Gremlin Server. Edge list format is a bit easier for non-JVM languages to work
* with as a format and doesn't require a cache for loading (as vertex labels are not serialized in adjacency
* list).
*/
final static class JacksonSerializer extends StdScalarSerializer {
public JacksonSerializer() {
super(OdbGraphTp3.class);
}
@Override
public void serialize(final OdbGraphTp3 graph, final JsonGenerator jsonGenerator, final SerializerProvider serializerProvider)
throws IOException {
jsonGenerator.writeStartObject();
jsonGenerator.writeFieldName(GraphSONTokens.VERTICES);
jsonGenerator.writeStartArray();
final Iterator vertices = graph.vertices();
while (vertices.hasNext()) {
serializerProvider.defaultSerializeValue(vertices.next(), jsonGenerator);
}
jsonGenerator.writeEndArray();
jsonGenerator.writeFieldName(GraphSONTokens.EDGES);
jsonGenerator.writeStartArray();
final Iterator edges = graph.edges();
while (edges.hasNext()) {
serializerProvider.defaultSerializeValue(edges.next(), jsonGenerator);
}
jsonGenerator.writeEndArray();
jsonGenerator.writeEndObject();
}
}
/**
* Deserializes the edge list format.
*/
static class JacksonDeserializer extends StdDeserializer {
public JacksonDeserializer() {
super(OdbGraphTp3.class);
}
@Override
public OdbGraphTp3 deserialize(final JsonParser jsonParser, final DeserializationContext deserializationContext) throws IOException, JsonProcessingException {
throw new UnsupportedOperationException();
// final Configuration conf = new BaseConfiguration();
// conf.setProperty("gremlin.tinkergraph.defaultVertexPropertyCardinality", "list");
// final OdbGraphTp3 graph = OdbGraphTp3.open(conf);
//
// while (jsonParser.nextToken() != JsonToken.END_OBJECT) {
// if (jsonParser.getCurrentName().equals("vertices")) {
// while (jsonParser.nextToken() != JsonToken.END_ARRAY) {
// if (jsonParser.currentToken() == JsonToken.START_OBJECT) {
// final DetachedVertex v = (DetachedVertex) deserializationContext.readValue(jsonParser, Vertex.class);
// v.attach(Attachable.Method.getOrCreate(graph));
// }
// }
// } else if (jsonParser.getCurrentName().equals("edges")) {
// while (jsonParser.nextToken() != JsonToken.END_ARRAY) {
// if (jsonParser.currentToken() == JsonToken.START_OBJECT) {
// final DetachedEdge e = (DetachedEdge) deserializationContext.readValue(jsonParser, Edge.class);
// e.attach(Attachable.Method.getOrCreate(graph));
// }
// }
// }
// }
//
// return graph;
}
@Override
public boolean isCachable() {
return true;
}
}
}
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