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First, I follow these steps to create a graph in JanusGraph.

  • add the following to conf/janusgraph-cassandra-configurationgraph.properties
index.search.backend = elasticsearch
index.search.hostname = 127.0.0.1
index.search.elasticsearch.transport-scheme = http

  • change "ConfigurationManagementGraph: conf/janusgraph-cql-configurationgraph.properties" in gremlin-server-configuration.yaml to "ConfigurationManagementGraph: conf/janusgraph-cassandra-configurationgraph.properties"

  • change conf/gremlin-server/gremlin-server.yaml to conf/gremlin-server/gremlin-server.yaml.orig

  • change conf/gremlin-server/gremlin-server-configuration.yaml to conf/gremlin-server/gremlin-server.yaml

  • run bin/janusgraph.sh start

  • run bin/gremlin.sh

  • run 

:remote connect tinkerpop.server conf/remote.yaml session
:remote console

map = new HashMap<String, Object>();
map.put("storage.backend", "cassandrathrift");
map.put("storage.hostname", "127.0.0.1");
map.put("graph.graphname", "KG");
map.put("index.search.backend", "elasticsearch");
map.put("index.search.hostname", "127.0.0.1");
map.put("index.search.elasticsearch.transport-scheme", "http");

ConfiguredGraphFactory.createConfiguration(new MapConfiguration(map));
graph=ConfiguredGraphFactory.open("KG");

g=graph.traversal();


ConfiguredGraphFactory.getGraphNames()

  • turn off janusgraph, run bin/janusgraph.sh stop

  • make a copy of conf/janusgraph-cassandra-es.properties to conf/KG.properties

  • add the following two lines to the top of conf/KG.properties

gremlin.graph=org.janusgraph.core.ConfiguredGraphFactory
graph.graphname=KG
  • open conf/gremlin-server/gremlin-server.yaml, and add the following line to graphs:
KG: conf/KG.properties

  • add "scripts/empty-sample.groovy" to "org.apache.tinkerpop.gremlin.jsr223.ScriptFileGremlinPlugin:"

  • open script/empty-sample.groovy, change the last line to the following:

globals << [g : KG.traversal()]
  • start janusgraph again by running bin/janusgraph.sh start

Second, I run bin/gremlin.sh

  • run
:remote connect tinkerpop.server conf/remote.yaml session
:remote console
graph=ConfiguredGraphFactory.open("KG");
g=graph.traversal();
g.addV('user').property('name', 'Robert')
g.V()
  • I can see it returns a vertex ==>v[4120]

Third, however, when I exit from gremlin console, and get into the gremlin console again like above, when I try to query g.V(), I see nothing returned.

Any idea why this is happening? Thank you very much!

Robert Huang
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1 Answers1

5

I think it's because you failed to close the transaction with g.tx().commit() after you add your vertex.

Note that Gremlin Server does manage sessions and calls commit() for you, but by doing:

:remote connect tinkerpop.server conf/remote.yaml session

you've explicitly opened a connection that does not manage sessions. If you want a session that is managed and auto-commits on every request then you need to do:

:remote connect tinkerpop.server conf/remote.yaml session-managed

http://tinkerpop.apache.org/docs/current/reference/#console-sessions

stephen mallette
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