janusgraph-users@lists.lfaidata.foundation

Re: Connecting to server from java: can't lock berkeleyje

hadoopmarc@...

#6621

The stacktrace is not very helpful, unfortunately, but that is not your doing. The original example does not use an "ats" variable but instantiates g with a oneliner, but it hard to see why this could make a difference. Most likely, the code has trouble finding the conf/remote-objects.yaml file, referenced in the conf/remote-graph.properties file.

As an alternative to fiddling with your current code, you could take a look at:

https://github.com/JanusGraph/janusgraph/tree/v0.6.2/janusgraph-examples/example-remotegraph

Best wishes, Marc

Re: Connecting to server from java: can't lock berkeleyje

queshaw

#6620

D'oh... So, after that, I get a NullPointerException:

AnonymousTraversalSource<GraphTraversalSource> ats = traversal(); // not null

if (new File(props).exists()) // path to conf/remote-graph.properties

g = ats.withRemote(props);

java.lang.IllegalStateException: java.lang.reflect.InvocationTargetException

at org.apache.tinkerpop.gremlin.process.remote.RemoteConnection.from(RemoteConnection.java:73)

at org.apache.tinkerpop.gremlin.process.traversal.AnonymousTraversalSource.withRemote(AnonymousTraversalSource.java:76)

at org.apache.tinkerpop.gremlin.process.traversal.AnonymousTraversalSource.withRemote(AnonymousTraversalSource.java:66)

at lnf.graph.Queries.go(Queries.java:52)

at lnf.graph.Queries.main(Queries.java:41)

Caused by: java.lang.reflect.InvocationTargetException

at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)

at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)

at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)

at java.lang.reflect.Constructor.newInstance(Constructor.java:423)

at org.apache.tinkerpop.gremlin.process.remote.RemoteConnection.from(RemoteConnection.java:71)

... 4 more

Caused by: java.lang.IllegalStateException: java.lang.NullPointerException

at org.apache.tinkerpop.gremlin.driver.remote.DriverRemoteConnection.<init>(DriverRemoteConnection.java:84)

... 9 more

Caused by: java.lang.NullPointerException

at org.apache.tinkerpop.gremlin.driver.Cluster.open(Cluster.java:255)

at org.apache.tinkerpop.gremlin.driver.remote.DriverRemoteConnection.<init>(DriverRemoteConnection.java:80)

... 9 more

The server is running and I can connect from gremlin shell.

Show quoted text

On Sunday, September 11, 2022 5:03 AM, hadoopmarc@... wrote:

You can take a look at:

https://docs.janusgraph.org/interactions/connecting/java/

Apparently, you used JanusGraphFactory, which opens an embedded JanusGraph instance in the client. If you want to client to connect to a JanusGraph serrver, you use need the g = traversal().withRemote() syntax as shown in the link above.

Best wishes,

Marc

Re: Janusgraph-full-0.6.1: how to fix "WARNING: Critical severity vulnerabilities were found with Log4j!"

Yingjie Li

#6619

Hello Marc,

Yes. Now it works!

Thanks

Yingjie

Show quoted text

On Fri, Sep 9, 2022 at 4:08 PM <hadoopmarc@...> wrote:

Hi Yingjie,

My suggestion was incomplete. In addition to removing the log4j-1.2.17.jar file from the lib folder, you have to remove the slf4j-log4j12-1.7.30.jar file as well. Otherwise, JanusGraph server starts looking for the log4j jar and crashes, as you found out.

Best wishes, Marc

Re: Connecting to server from java: can't lock berkeleyje

hadoopmarc@...

#6618

You can take a look at:

https://docs.janusgraph.org/interactions/connecting/java/

Apparently, you used JanusGraphFactory, which opens an embedded JanusGraph instance in the client. If you want to client to connect to a JanusGraph serrver, you use need the g = traversal().withRemote() syntax as shown in the link above.

Best wishes,

Marc

Re: Connecting to server from java: can't lock berkeleyje

queshaw

#6617

I should probably add I intend to use import static org.janusgraph.core.attribute.Text.* for textContains etc.

Show quoted text

On Saturday, September 10, 2022 8:50 AM, queshaw <queshaw@...> wrote:

I'm trying to connect to janusgraph server from java. If I follow the instructions in the documentation, using this in gradle:

    implementation 'org.janusgraph:janusgraph-driver:0.6.2'
    implementation 'org.apache.tinkerpop:gremlin-driver:3.5.3'

JanusGraph and JanusGraphFactory can't be found. If I add:

    implementation 'org.janusgraph:janusgraph-core:0.6.2'

and I use conf/remote-graph.properties, I get an error message that root.storage.backend needs to be defined. I don't find that property, but if I add:

storage.backend=berkeleyje

then I get Could not find implementation class: org.janusgraph.diskstorage.berkeleyje.BerkeleyJEStoreManager

If I add:

    implementation 'org.janusgraph:janusgraph-berkeleyje:0.6.2'

then I get:

Please supply configuration parameter "storage.directory" or both "storage.root" and "graph.graphname".

If I add:

storage.directory=/somewhere/graph/berkeleyje

then I get:

/somewhere/graph/berkeleyje The environment cannot be locked for single writer access. ENV_LOCKED: The je.lck file could not be locked. Environment is invalid and must be closed.

I think that is because the server is running and the file is locked.

How can I connect to a running server remotely from java, if I'm using berkeleyje? I've been able to connect to the server to run queries from python and from gremlin shell.

Thanks.

Connecting to server from java: can't lock berkeleyje

queshaw

#6616

I'm trying to connect to janusgraph server from java. If I follow the instructions in the documentation, using this in gradle:

implementation 'org.janusgraph:janusgraph-driver:0.6.2'

implementation 'org.apache.tinkerpop:gremlin-driver:3.5.3'

JanusGraph and JanusGraphFactory can't be found. If I add:

implementation 'org.janusgraph:janusgraph-core:0.6.2'

and I use conf/remote-graph.properties, I get an error message that root.storage.backend needs to be defined. I don't find that property, but if I add:

storage.backend=berkeleyje

then I get Could not find implementation class: org.janusgraph.diskstorage.berkeleyje.BerkeleyJEStoreManager

If I add:

implementation 'org.janusgraph:janusgraph-berkeleyje:0.6.2'

then I get:

Please supply configuration parameter "storage.directory" or both "storage.root" and "graph.graphname".

If I add:

storage.directory=/somewhere/graph/berkeleyje

then I get:

/somewhere/graph/berkeleyje The environment cannot be locked for single writer access. ENV_LOCKED: The je.lck file could not be locked. Environment is invalid and must be closed.

I think that is because the server is running and the file is locked.

How can I connect to a running server remotely from java, if I'm using berkeleyje? I've been able to connect to the server to run queries from python and from gremlin shell.

Thanks.

Re: Janusgraph-full-0.6.1: how to fix "WARNING: Critical severity vulnerabilities were found with Log4j!"

hadoopmarc@...

#6615

Hi Yingjie,

My suggestion was incomplete. In addition to removing the log4j-1.2.17.jar file from the lib folder, you have to remove the slf4j-log4j12-1.7.30.jar file as well. Otherwise, JanusGraph server starts looking for the log4j jar and crashes, as you found out.

Best wishes, Marc

Re: Janusgraph-full-0.6.1: how to fix "WARNING: Critical severity vulnerabilities were found with Log4j!"

Yingjie Li

#6614

On Sat, Aug 20, 2022 at 09:28 AM, <hadoopmarc@...> wrote:

The JanusGraph and TinkerPop code only explicitly depend on slfj4j, so you can choose the logging implementation. you want You can simply remove the log4j-1.2.17.jar from the lib folder of the janusgraph binary distribution or exclude it in the pom.xml of any project depending on janusgraph.
Note that janusgraph also ships with logback and provides a sample config in conf/logback.xml.

Hello Marc,
If I remove log4j-1.2.17.jar from the lib directory of janusgraph distribution, say janusgraph-full-0.6.2/lib,then the janusgraph server can not be started. Below is the error message, and there is no janusgraph.log writen out.
Am I missing anything?

Thanks,
Yingjie

......

Forking Cassandra...

Running `nodetool statusbinary`.... OK (returned exit status 0 and printed string "running").

Forking Elasticsearch...

Connecting to Elasticsearch (127.0.0.1:9200)....... OK (connected to 127.0.0.1:9200).

Forking JanusGraph-Server...

Connecting to JanusGraph-Server (127.0.0.1:8182)............................. timeout exceeded (60 seconds): could not connect to 127.0.0.1:8182

See janusgraph install directory/bin/../logs/janusgraph.log for JanusGraph-Server log output.

Re: Cannot pass list of maps to withSideEffect

Florian Hockmann

#6613

Oh wow, I assumed that Gremlin.Net would throw if it has no GraphSON serializer for a given type but turns out that it just provides the object unchanged to the JsonSerializer from System.Text.Json which results in a JSON serialization that is not strongly typed like it should be with GraphSON. This is the result for your example:

{"@type":"g:List","@value":[{"X":1,"Y":2},{"X":3,"Y":4}]}

I’m not sure if this is a bug or a feature to be honest, but this sentence from the GraphSON 3 spec at least sounds like this shouldn’t be possible:

“GraphSON 3.0 does not have an option to be typeless. Types are always embedded except for strings and boolean values which are inferred from JSON types.”

https://tinkerpop.apache.org/docs/current/dev/io/#graphson-3d0

I created another issue for this: https://issues.apache.org/jira/browse/TINKERPOP-2788

Von: janusgraph-users@... <janusgraph-users@...> Im Auftrag von bill.poole via lists.lfaidata.foundation
Gesendet: Mittwoch, 31. August 2022 17:58
An: janusgraph-users@...
Betreff: Re: [janusgraph-users] Cannot pass list of maps to withSideEffect

Thanks Florian. I’ve created the issue with TinkerPop here.

You said that using my own class XXX cannot work, but strangely it seems to with the following code showing the injected array of XXX objects being successfully returned from the server:

var xxx = new[] { new XXX { X = 1, Y = 2 }, new XXX { X = 3, Y = 4 } };

var result = (List<object>)await g.Inject<object>(xxx).Promise(t => t.ToList());

foreach (var x in result)

{

foreach (var pair in (Dictionary<object, object>)x)

{

Console.WriteLine($"{pair.Key}: {pair.Value}");

}

… which displays:

X: 1

Y: 2

X: 3

Y: 4

Show quoted text

From: janusgraph-users@... <janusgraph-users@...> On Behalf Of Florian Hockmann
Sent: Wednesday, 31 August 2022 10:11 PM
To: janusgraph-users@...
Subject: Re: [janusgraph-users] Cannot pass list of maps to withSideEffect

This sounds like a bug in Gremlin.Net to me, especially since it’s working with the Inject() step. Could you please create an issue with the TinkerPop (to which Gremlin.Net belongs) project here: https://issues.apache.org/jira/browse/TINKERPOP/ ?

Your second example with your own class XXX however cannot work as Gremlin.Net and Gremlin Server / JanusGraph Server cannot know how to serialize / deserialize this type. You would need to write your own serializer and deserializer for this type to make it work.

Von: janusgraph-users@... <janusgraph-users@...> Im Auftrag von bill.poole via lists.lfaidata.foundation
Gesendet: Mittwoch, 31. August 2022 15:54
An: janusgraph-users@...
Betreff: [janusgraph-users] Cannot pass list of maps to withSideEffect

Hi All – I’m trying to use the withSideEffect() configuration to add a list of maps to GraphTraversalSource like is done in the Long Traversals recipe and the server throws an exception – “Could not deserialize the Traversal instance java.lang.IllegalStateException: Could not locate method: GraphTraversalSource.withSideEffect(String, LinkedHashMap, LinkedHashMap)”

The .NET code that reproduces the error:

var server = new GremlinServer("localhost", port: 8182);

var client = JanusGraphClientBuilder.BuildClientForServer(server).Create();

using var connection = new DriverRemoteConnection(client);

var g = AnonymousTraversalSource.Traversal().WithRemote(connection);

var xxx = new[]

{

new Dictionary<object, object> { { "x", 1 }, { "y", 2 } },

new Dictionary<object, object> { { "x", 3 }, { "y", 4 } }

};

await g.WithSideEffect("xxx", xxx).V().Promise(t => t.ToList());

The same result is produced using an array of strongly typed objects:

public class XXX

{

public int X { get; init; }

public int Y { get; init; }

}

var server = new GremlinServer("localhost", port: 8182);

var client = JanusGraphClientBuilder.BuildClientForServer(server).Create();

using var connection = new DriverRemoteConnection(client);

var g = AnonymousTraversalSource.Traversal().WithRemote(connection);

var xxx = new[] { new XXX { X = 1, Y = 2 }, new XXX { X = 3, Y = 4 } };

await g.WithSideEffect("xxx", xxx).V().Promise(t => t.ToList());

However, the “inject” step works fine passing an array of maps:

await g.Inject<object>(xxx).Promise(t => t.ToList());

Invoking “withSideEffect” produces the following error on the server:

ERROR org.apache.tinkerpop.gremlin.server.op.traversal.TraversalOpProcessor - Could not deserialize the Traversal instance

java.lang.IllegalStateException: Could not locate method: GraphTraversalSource.withSideEffect(String, LinkedHashMap, LinkedHashMap)

at org.apache.tinkerpop.gremlin.jsr223.JavaTranslator.invokeMethod(JavaTranslator.java:300)

at org.apache.tinkerpop.gremlin.jsr223.JavaTranslator.translate(JavaTranslator.java:85)

at org.apache.tinkerpop.gremlin.server.op.traversal.TraversalOpProcessor.iterateBytecodeTraversal(TraversalOpProcessor.java:181)

at org.apache.tinkerpop.gremlin.server.handler.OpExecutorHandler.channelRead0(OpExecutorHandler.java:67)

at org.apache.tinkerpop.gremlin.server.handler.OpExecutorHandler.channelRead0(OpExecutorHandler.java:43)

at io.netty.channel.SimpleChannelInboundHandler.channelRead(SimpleChannelInboundHandler.java:99)

at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379)

at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365)

at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357)

at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:103)