OrientDB and Rexster

[Nigel Brown]

I have an existing system running titan/rexster/rexster-plugin. I am interested in swapping titan for orientdb.

I have orient 2.2 and rexster 2.5.0 set up like so

        <graph>
          <graph-enabled>true</graph-enabled>
          <graph-name>g</graph-name>
          <graph-type>com.tinkerpop.rexster.OrientGraphConfiguration</graph-type>
          <graph-location>remote:localhost/datagraph</graph-location>
            <properties>
            <username>root</username>
            <password>xxxx</password>
            </properties>
            <extensions>
              <allows>
                <allow>plgin:origin</allow>
              </allows>

            </extensions>
        </graph>

My plugin is receiving post/get requests (I step through the code), which it then processes and returns good results at the end of the @ExtensionDefinition .

Unfortunately, lower down the call stack an exception is thrown because Orient does not supportsThreadIsolatedTransactions . The get response just states "Internal Error".

My question is how to avoid this?

What are the supported versions of rexster and orientdb (if any)?

And a bonus question, what is the status of Tinkerpop3?

[Oleksandr Gubchenko]

For information about supported rexster see: http://orientdb.com/docs/last/Rexster.html

[Nigel Brown]

There seem to be mistakes on that linked page - that was what I was originally following. Assuming OrientDB 2.2, rexster 2.5.0 does not seem to work, 2.6.0 does.

There is a typo

      <graph-type>orientgraph</graph-type>
      <graph-file>url-to-your-db</graph-file>

should be more like

      <graph-type>com.tinkerpop.blueprints.pgm.impls.orientdb.OrientGraph</graph-type>
      <graph-location>url-to-your-db</graph-location>

With the above changes I got my plug-in/graph working.

One pain point for us was that you are not allowed periods (.) in property names. Another is that there is no regex query in the Gremlin API. This was something we used from Titan and non standard. We will probably be able to query OrientDB directly for some of our cases, but some are in the middle of a pipeline and that will be harder.

'And a bonus question, what is the status of Tinkerpop3?'

This seems to have gone very quiet. Some say it should have been out last December, but it wasn't.