Apache TinkerPopAT
Apache TinkerPop•2y ago
dracule_redrose

Serialization Issue

I have a weird error, when I am connecting with JanusGraph gremlin client using conf/remote-graph-binary.yaml I am able to get results. But when I am trying to use my java application I am getting, java.io.IOException: Serializer for custom type 'janusgraph.RelationIdentifier' not found. Googling around I got that this is due to serialization issue. It looks to me that the gremlin-client and my java application has similar configs but gremlin-client is not having any serialization problem. 

hosts: [localhost]
port: 8182
serializer: { className: org.apache.tinkerpop.gremlin.util.ser.GraphBinaryMessageSerializerV1, config: { ioRegistries: [org.janusgraph.graphdb.tinkerpop.JanusGraphIoRegistry] }}


Code setting up the serialization:

import org.apache.tinkerpop.gremlin.structure.io.binary.TypeSerializerRegistry;
import org.janusgraph.graphdb.tinkerpop.JanusGraphIoRegistry;
import org.apache.tinkerpop.gremlin.util.ser.GraphBinaryMessageSerializerV1;
...
       TypeSerializerRegistry typeSerializerRegistry = TypeSerializerRegistry.build()
                .addRegistry(JanusGraphIoRegistry.getInstance())
                .create();

        // Build cluster and connect client
        Cluster cluster = Cluster.build(host)
                .port(port)
                .serializer(new GraphBinaryMessageSerializerV1(typeSerializerRegistry))
                .maxConnectionPoolSize(1)
                .minConnectionPoolSize(1)
                .maxInProcessPerConnection(1)
                .minSimultaneousUsagePerConnection(1)
                .maxSimultaneousUsagePerConnection(1)
                .create();
        Client client = cluster.connect();
...
Solution
I have faced a similar issue in the past (but mostly related to gremlin-python) and @Boxuan Li suggested a solution in the JanusGraph discord server. It was something like along these lines:

private static MessageSerializer createGraphBinaryMessageSerializerV1() {
  final GraphBinaryMessageSerializerV1 serializer = new GraphBinaryMessageSerializerV1();
  final Map<String, Object> config = new HashMap<>();
  config.put(GraphBinaryMessageSerializerV1.TOKEN_IO_REGISTRIES, Collections.singletonList(JanusGraphIoRegistry.class.getName()));
  serializer.configure(config, Collections.emptyMap());
  return serializer;
}

and 
Cluster cluster = Cluster.build()
    .addContactPoint(gremlinServer)
    .port(gremlinServerPort)
    // .serializer(new GraphBinaryMessageSerializerV1(typeSerializerRegistry))
    .serializer(createGraphBinaryMessageSerializerV1())
    .create();

Also, here is how he suggested to setup the serializers in the JanusGraph config file:
https://github.com/Citegraph/citegraph/blob/main/backend/src/main/resources/gremlin-server-cql.yaml

I hope this leads you closer to a solution.
GitHub
citegraph/backend/src/main/resources/gremlin-server-cql.yaml at mai...
CiteGraph: A citation graph web visualizer. Contribute to Citegraph/citegraph development by creating an account on GitHub.
Jump to solution
Was this page helpful?