Working example?

[maciossek]

I've been trying to get an example to work. Any help appreciated:

Stackoverflow post: https://stackoverflow.com/questions/49917571/working-gremlin-javascript-example

gremlin-server 3.3.2 conf/gremlin-server-modern.yaml npm gremlin lib (js) 3.3.2

import gremlin from 'gremlin';
import DriverRemoteConnection from 'gremlin/lib/driver/driver-remote-connection';
import { Graph } from 'gremlin/lib/structure/graph';
const graph = new Graph()
const g = graph.traversal().withRemote(new DriverRemoteConnection('ws://localhost:8182/gremlin', { mimeType: 'application/vnd.gremlin-v3.0+json' }));

const fetchById = async (id) => {
  const result = await g.V(id).toList()
  console.log(result);
}

const addUser = async (name) => {
  const newVertex = await g.addV().property('name','marko').property('name','marko a. rodriguez').next()
  console.log(newVertex)
}

addUser()
fetchById(0)

Current Output:

[]
{ value: null, done: true }

[maciossek]

The answer: Gremlin JavaScript doesn't support GraphSON3 serialization, which is the default in TinkerPop 3.3+. This causes your response to not be properly parsed. Compare: https://issues.apache.org/jira/browse/TINKERPOP-1943

Many thanks @jorgebay

This is a working conf file for the server:

host: localhost
port: 8182
scriptEvaluationTimeout: 30000
graphs: {
  graph: conf/tinkergraph-empty.properties}
scriptEngines: {
  gremlin-groovy: {
    plugins: { org.apache.tinkerpop.gremlin.server.jsr223.GremlinServerGremlinPlugin: {},
               org.apache.tinkerpop.gremlin.tinkergraph.jsr223.TinkerGraphGremlinPlugin: {},
               org.apache.tinkerpop.gremlin.jsr223.ImportGremlinPlugin: {classImports: [java.lang.Math], methodImports: [java.lang.Math#*]},
               org.apache.tinkerpop.gremlin.jsr223.ScriptFileGremlinPlugin: {files: [scripts/generate-modern.groovy]}}}}
serializers:
  - { className: org.apache.tinkerpop.gremlin.driver.ser.GraphSONMessageSerializerGremlinV2d0, config: { ioRegistries: [org.apache.tinkerpop.gremlin.tinkergraph.structure.TinkerIoRegistryV2d0] }}
  - { className: org.apache.tinkerpop.gremlin.driver.ser.GryoMessageSerializerV3d0, config: { ioRegistries: [org.apache.tinkerpop.gremlin.tinkergraph.structure.TinkerIoRegistryV3d0] }}            # application/vnd.gremlin-v3.0+gryo
  - { className: org.apache.tinkerpop.gremlin.driver.ser.GryoMessageSerializerV3d0, config: { serializeResultToString: true }}                                                                      # application/vnd.gremlin-v3.0+gryo-stringd
  - { className: org.apache.tinkerpop.gremlin.driver.ser.GraphSONMessageSerializerV3d0, config: { ioRegistries: [org.apache.tinkerpop.gremlin.tinkergraph.structure.TinkerIoRegistryV3d0] }}        # application/json
metrics: {
  slf4jReporter: {enabled: true, interval: 180000}}
strictTransactionManagement: false
idleConnectionTimeout: 0
keepAliveInterval: 0
maxInitialLineLength: 4096
maxHeaderSize: 8192
maxChunkSize: 8192
maxContentLength: 65536
maxAccumulationBufferComponents: 1024
resultIterationBatchSize: 64

The TinkerIoRegistryV2d0 part is the added compared to the regular gremlin-server-modern.yaml

[jorgebay]

Thanks @maciossek for summarizing the workaround here for future reference.

While we add support for GraphSON3 (hopefully for next release), in the meantime, we plan to include in the TinkerPop documentation a note about enabling GraphSON2 for the JavaScript GLV.