如何为远程GraphTraversalSource创建Vertex Index

如何使用traversal().withRemote("conf/remote-graph.properties")创建顶点索引（Vertex Indexes）？

具体疑问 #

• 是否必须创建org.apache.tinkerpop.gremlin.structure.Graph实例？

  Graph graph = TinkerGraph.open(configuration);
  

• 若是，JanusGraph所需的配置在哪里获取？
  对比OrientDB 3.2.18 GA Community Edition搭配Orientdb-Gremlin的OrientGraph.java示例代码：

  Configuration configuration = new BaseConfiguration();
  configuration.setProperty(OrientGraph.CONFIG_URL, orientGraph_configUrl);
  configuration.setProperty(OrientGraph.CONFIG_USER, orientGraph_configUser);
  configuration.setProperty(OrientGraph.CONFIG_PASS, orientGraph_configPass);
  configuration.setProperty(OrientGraph.CONFIG_TRANSACTIONAL, true);
  OrientGraph orientGraph = OrientGraph.open(configuration);
  GraphTraversalSource g = orientGraph.traversal();
  

• 若必须创建，如何编写可正常连接的最简JanusGraphManagement实例代码？

调研发现 #

• g.V().index();方法位于org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.GraphTraversal中
  有相关示例，但目前仍未完全理解该方法的用法：

  g.V().hasLabel("software").index() //1
  g.V().hasLabel("software").values("name").fold().
      order(Scope.local).
      index().
      unfold().
      order().
          by(__.tail(Scope.local, 1)) //2
  g.V().hasLabel("software").values("name").fold().
      order(Scope.local).
      index().
        with(WithOptions.indexer, WithOptions.list).
      unfold().
      order().
        by(__.tail(Scope.local, 1)) //3
  g.V().hasLabel("person").values("name").fold().
      order(Scope.local).
      index().
          with(WithOptions.indexer, WithOptions.map)  //4
  

• Tinkergraph有createIndex()方法，示例代码：

  graph = TinkerGraph.open()
  graph.createIndex("username",Vertex.class)
  

• JanusGraph索引使用JanusGraphManagement.buildIndex(String, Class)方法，但希望编写更贴近Gremlin、更通用的代码

现有代码 #

已知如何在Gremlin中使用空白TinkerGraph实现，但需要连接localhost:8182上已有的JanusGraph：

graph = TinkerGraph.open()
g = traversal().withEmbedded(graph)
g.io('data/grateful-dead.xml').read().iterate()
clock(1000) {g.V().has('name','Garcia').iterate()} //// (1)
graph = TinkerGraph.open()
g = traversal().withEmbedded(graph)
graph.createIndex('name',Vertex.class)
g.io('data/grateful-dead.xml').read().iterate()
clock(1000){g.V().has('name','Garcia').iterate()} //2

内容的提问来源于stack exchange，提问作者Zach