Revision:
I have a stand-alone version of Cassandra. I launch that using the following command:
./cassandra -f
I also have a Java Application that the Titan Graph Library installed. To obtain a TitanGraph object I use the following code:
BaseConfiguration configuration = new BaseConfiguration();
configuration.setProperty("storage.backend", "cassandra");
configuration.setProperty("storage.hostname", "127.0.0.1");
TitanGraph graph = TitanFactory.open(configuration);
After this I can add Vertices/Edges and Query them as well. I did an additional check on the local Cassandra database and can verify there are records being generated and persisted
cqlsh> select count(*) from titan.edgestore;
count
--------
185050
(1 rows)
The problem arises when I launch the rexster-server. I am launching this in stand-alone mode using the following command:
./rexster.sh -s -c ../config/rexster.xml
Then I launch the rexster console and load the graph. The issues is that the graph seems to contain no data? I am really not sure what is going on here. There is only 1 instance of Cassandra running.
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(_______( 0 0
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l l-----l l
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opening session [127.0.0.1:8184]
?h for help
rexster[groovy]> ?h
-= Console Specific =-
?<language-name>: jump to engine
?l: list of available languages on Rexster
?b: print available bindings in the session
?r: reset the rexster session
?e <file-name>: execute a script file
?q: quit
?h: displays this message
-= Rexster Context =-
rexster.getGraph(graphName) - gets a Graph instance
:graphName - [String] - the name of a graph configured within Rexster
rexster.getGraphNames() - gets the set of graph names configured within Rexster
rexster.getVersion() - gets the version of Rexster server
rexster[groovy]> rexster.getGraphNames()
==>kpdlp
rexster[groovy]> rexster.getGraph('graph')
==>titangraph[cassandrathrift:[127.0.0.1]]
rexster[groovy]> g = rexster.getGraph('graph')
==>titangraph[cassandrathrift:[127.0.0.1]]
rexster[groovy]> g.V.count()
==>0
rexster[groovy]>
Below is the rexster.xml I am using
<?xml version="1.0" encoding="UTF-8"?>
<rexster>
<http>
<server-port>8182</server-port>
<server-host>0.0.0.0</server-host>
<base-uri>http://localhost</base-uri>
<web-root>public</web-root>
<character-set>UTF-8</character-set>
<enable-jmx>false</enable-jmx>
<enable-doghouse>true</enable-doghouse>
<max-post-size>2097152</max-post-size>
<max-header-size>8192</max-header-size>
<upload-timeout-millis>30000</upload-timeout-millis>
<thread-pool>
<worker>
<core-size>8</core-size>
<max-size>8</max-size>
</worker>
<kernal>
<core-size>4</core-size>
<max-size>4</max-size>
</kernal>
</thread-pool>
<io-strategy>leader-follower</io-strategy>
</http>
<rexpro>
<server-port>8184</server-port>
<server-host>0.0.0.0</server-host>
<session-max-idle>1790000</session-max-idle>
<session-check-interval>3000000</session-check-interval>
<read-buffer>65536</read-buffer>
<enable-jmx>false</enable-jmx>
<thread-pool>
<worker>
<core-size>8</core-size>
<max-size>8</max-size>
</worker>
<kernal>
<core-size>4</core-size>
<max-size>4</max-size>
</kernal>
</thread-pool>
<io-strategy>leader-follower</io-strategy>
</rexpro>
<shutdown-port>8183</shutdown-port>
<shutdown-host>127.0.0.1</shutdown-host>
<config-check-interval>10000</config-check-interval>
<script-engines>
<script-engine>
<name>gremlin-groovy</name>
<reset-threshold>-1</reset-threshold>
<init-scripts>config/init.groovy</init-scripts>
<imports>com.tinkerpop.rexster.client.*</imports>
<static-imports>java.lang.Math.PI</static-imports>
</script-engine>
</script-engines>
<security>
<authentication>
<type>none</type>
<configuration>
<users>
<user>
<username>rexster</username>
<password>rexster</password>
</user>
</users>
</configuration>
</authentication>
</security>
<metrics>
<reporter>
<type>jmx</type>
</reporter>
<reporter>
<type>http</type>
</reporter>
<reporter>
<type>console</type>
<properties>
<rates-time-unit>SECONDS</rates-time-unit>
<duration-time-unit>SECONDS</duration-time-unit>
<report-period>10</report-period>
<report-time-unit>MINUTES</report-time-unit>
<includes>http.rest.*</includes>
<excludes>http.rest.*.delete</excludes>
</properties>
</reporter>
</metrics>
<graphs>
<graph>
<graph-name>graph</graph-name>
<graph-type>com.thinkaurelius.titan.tinkerpop.rexster.TitanGraphConfiguration</graph-type>
<graph-location></graph-location>
<graph-read-only>false</graph-read-only>
<properties>
<storage.backend>cassandrathrift</storage.backend>
<storage.hostname>127.0.0.1</storage.hostname>
</properties>
<extensions>
<allows>
<allow>tp:gremlin</allow>
</allows>
</extensions>
</graph>
</graphs>
</rexster>
Perhaps there is just some confusion in Rexster's role. Your question was:
Note that using
TitanFactory
will open aTitanGraph
instance that connects directly to cassandra. That has nothing to do with Rexster. If you want to connect to Rexster (which remotely holds aTitanGraph
instance given your configuration) then you must do so through REST or RexPro. With the more simple approach for verifying operations being REST, try to curl:That should return some JSON that contains the name of the
TitanGraph
instance you configured in the<graph-name>
field inrexster.xml
. The<graph-name>
simply identifies the graph instance in Rexster so that you can uniquely identify it in requests when there are multiple instances hosted in there.