Concurrency issues when the driver is used on a Gremlin Server

[fourier134949]

Hi, We have integrated the neo4j-gremlin-bolt driver into a gremlin server. Below the steps:

• Download and unzip gremlin server (http://apache.mirrors.lucidnetworks.net/tinkerpop/3.4.2/apache-tinkerpop-gremlin-server-3.4.2-bin.zip)

• Execute bin/gremlin-server.sh install org.apache.tinkerpop neo4j-gremlin 3.4.2

• Create neo4j-bolt.properties file in conf directory as follows : ################################################################# gremlin.graph=com.steelbridgelabs.oss.neo4j.structure.Neo4JGraph

  neo4j.graph.name=graph.db

  neo4j.identifier=dummy neo4j.url=bolt://localhost:7687 neo4j.username=neo4j neo4j.password= neo4j.readonly=false neo4j.vertexIdProvider=com.steelbridgelabs.oss.neo4j.structure.providers.Neo4JNativeElementIdProvider neo4j.edgeIdProvider=com.steelbridgelabs.oss.neo4j.structure.providers.Neo4JNativeElementIdProvider ################################################################## *neo4j.password : edit this field with your neo4j password.

• Edit gremlin-server-neo4j.yaml as follows :

graphs: { graph: conf/neo4j-bolt.properties}

• Build neo4j-gremlin-bolt.jar and put it in folder ext/neo4j-gremlin/plugins

• Download the neo4j java driver and put it in folder ext/neo4j-gremlin/plugins

• Start Gremlin Server: bin/gremlin-server.sh ./conf/gremlin-server-neo4j.yaml

We have configured two gremlin console instances, both pointing at the same gremlin server instance. Below the steps for installing a console instance:

• Download and unzip the console: (http://apache.osuosl.org/tinkerpop/3.4.2/apache-tinkerpop-gremlin-console-3.4.2-bin.zip)

• Start the console using : ./bin/gremlin.sh

• Install neo4j-gremlin plugin on console using below command →

  :install org.apache.tinkerpop neo4j-gremlin 3.4.2

• Restart the console: ":quit" came out and login using the ./bin/gremlin.sh command.

• Add the neo4j plugin:

  :plugin use tinkerpop.neo4j

• Connect to the server (make sure the remote.yaml file is configured with the right ip/port of the gremlin server)

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

==>Configured xx.xxx.xxx.xx/xx.xxx.xxx.xx:8182-[93b3521e-7de1-45d9-a5ca]

• Switch to remote console:

  :remote console

==>All scripts will now be sent to Gremlin Server - [xx.xxx.xxx.xx/xx.xxx.xxx.xx:8182]-[93b3521e-7de1-45d9-a5ca]

Repeat the steps for a second console.

On the first console type:

g.addV('book').property('name', 'The French Chef Cookbook') g.tx().commit()

You can repeat this step by creating/droppping nodes

On the second console type:

g.V()

The second console won't randomly see the updates performed on the first one. How can we solve this issue?

Thanks in advance

[rjbaucells]

It looks like the second console has an instance of the graph opened, all operations performed in that instance will be cached and only on TX commit/rollback will be flushed.

Try explicitly committing the TX on the second console, similar to the statement you are issuing on the first console.

[fourier134949]

Hi, We also executed the above statements between g.tx().open() and g.tx().commit() on both consoles and we experience the same issue

[fravdd81]

Same issue with two different consoles.