How do I connect to Neptune using Java

Question

I have the following code based on the docs...

@Controller
@RequestMapping("neptune")
public class NeptuneEndpoint {
    @GetMapping("")
    @ResponseBody
    public String test(){
        Cluster.Builder builder = Cluster.build();
        builder.addContactPoint("...endpoint...");
        builder.port(8182);

        Cluster cluster = builder.create();

        GraphTraversalSource g = EmptyGraph.instance()
                                           .traversal()
                                           .withRemote(
                                               DriverRemoteConnection.using(cluster)
                                           );

        GraphTraversal t = g.V().limit(2).valueMap();

        t.forEachRemaining(
                e ->  System.out.println(e)
        );

        cluster.close();
        return "Neptune Up";
    }
}

But when I try to run I get ...

java.util.concurrent.TimeoutException: Timed out while waiting for an available host - check the client configuration and connectivity to the server if this message persists

Also how would I add Secret key from AWS IAM account?

Do you need any other information with regards to this issue? — The-Big-K, Oct 24 '18 at 06:33

score 3 · Answer 1 · answered Jul 28 '18 at 11:39

Neptune doesn't allow you to connect to the db instance from your local machine. You can only connect to Neptune via an EC2 inside the same VPC as Neptune (aws documentation).

Try making a runnable jar of this code and run it inside an ec2, the code should work fine. If you're trying to debug something from your local system, then use PuTTY instance tunneling to connect to ec2 which then will be forwarded to neptune cluster.

score 2 · Answer 2 · answered Jul 01 '18 at 01:20

Have you created an instance with IAM auth enabled?

If yes, you will have to sign your request using SigV4. More information (and examples) on how to connect using SigV4 is available at https://docs.aws.amazon.com/neptune/latest/userguide/iam-auth-connecting-gremlin-java.html

The examples given in the documentation above also contain information on how to use your IAM credentials to connect to a Neptune cluster.

score 1 · Answer 3 · answered Jul 03 '18 at 15:27

1

I just had the same issue and the root cause was a dependency version conflict with Netty which is unfortunately a very pervasive dependency. Gremlin 3.3.2 uses io.netty/netty-all version 4.0.56.Final. You might find your project depends on another Netty jar such as io.netty/netty or io.netty/netty-handler both of which can cause issues so you will need to excluded them from other dependencies in your POM or use managed-dependencies to set a project level Netty version.

answered Jul 03 '18 at 15:27

shooit

11
1

For any one new, faced the same issue, updated all the drivers to latest and seems to work OOB. follow instructions here https://docs.aws.amazon.com/neptune/latest/userguide/iam-auth-connecting-gremlin-java.html and use following dependencies. group: 'org.apache.tinkerpop', name: 'gremlin-driver', version: '3.4.7' group: 'com.amazonaws', name: 'aws-java-sdk-core', version: '1.11.828' group: 'com.amazonaws', name: 'amazon-neptune-sigv4-signer', version: '2.0.2' group: 'com.amazonaws', name: 'amazon-neptune-gremlin-java-sigv4', version: '2.0.2' – sas1138 Jul 30 '20 at 11:29

score 0 · Answer 4 · answered Mar 12 '20 at 12:37

Another option is to use a AWS SigV4 signing proxy that acts as a bridge between Neptune and your local development environment. One of these proxies is https://github.com/monken/aws4-proxy

npm install --global aws4-proxy
# have your credentials exported as AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY
aws4-proxy --service neptune-db --endpoint cluster-die4eenu.cluster-eede5pho.eu-west-1.neptune.amazonaws.com --region eu-west-1
wscat localhost:3000/gremlin

score -1 · Answer 5 · answered Nov 05 '20 at 19:12

-1

Refer this

Note: You need to be in the same VPC to access Neptune cluster.

answered Nov 05 '20 at 19:12

HIMANSHU GOYAL

471
2
11

How do I connect to Neptune using Java

5 Answers5