cassandra-3.0 docker-container janusgraph tinkerpop3 java-17

JanusGraph-PropertyKey Is Not A User-Defined-Key

Problem

Why is JanusGraph throwing-up a User-Defined-Key problem when I'm just trying to make an index?

Logs

2023-05-08 12:40:25,640 [INFO] [c.d.o.d.i.c.ContactPoints.main] ::   Contact point localhost:9042 resolves to multiple addresses, will use them all ([localhost/127.0.0.1, localhost/0:0:0:0:0:0:0:1])
2023-05-08 12:40:25,731 [INFO] [c.d.o.d.i.c.DefaultMavenCoordinates.main] ::     DataStax Java driver for Apache Cassandra(R) (com.datastax.oss:java-driver-core) version 4.15.0
2023-05-08 12:40:26,173 [INFO] [c.d.o.d.i.c.t.Clock.JanusGraph Session-admin-0] ::   Using native clock for microsecond precision
2023-05-08 12:40:26,414 [WARN] [c.d.o.d.i.c.l.h.OptionalLocalDcHelper.JanusGraph Session-admin-0] ::     [JanusGraph Session|default] You specified datacenter1 as the local DC, but some contact points are from a different DC: Node(endPoint=localhost/127.0.0.1:9042, hostId=null, hashCode=6415177b)=null; please provide the correct local DC, or check your contact points
2023-05-08 12:40:26,643 [INFO] [o.j.g.i.UniqueInstanceIdRetriever.main] ::   Generated unique-instance-id=c0a8563c15928-rmt-lap-win201
2023-05-08 12:40:26,657 [INFO] [c.d.o.d.i.c.ContactPoints.main] ::   Contact point localhost:9042 resolves to multiple addresses, will use them all ([localhost/127.0.0.1, localhost/0:0:0:0:0:0:0:1])
2023-05-08 12:40:26,684 [INFO] [c.d.o.d.i.c.t.Clock.JanusGraph Session-admin-0] ::   Using native clock for microsecond precision
2023-05-08 12:40:26,724 [WARN] [c.d.o.d.i.c.l.h.OptionalLocalDcHelper.JanusGraph Session-admin-0] ::     [JanusGraph Session|default] You specified datacenter1 as the local DC, but some contact points are from a different DC: Node(endPoint=localhost/[0:0:0:0:0:0:0:1]:9042, hostId=null, hashCode=114c356b)=null; please provide the correct local DC, or check your contact points
2023-05-08 12:40:26,739 [INFO] [o.j.d.c.ExecutorServiceBuilder.main] ::  Initiated fixed thread pool of size 40
2023-05-08 12:40:26,845 [INFO] [o.j.g.d.StandardJanusGraph.main] ::  Gremlin script evaluation is disabled
2023-05-08 12:40:26,872 [INFO] [o.j.d.l.k.KCVSLog.main] ::   Loaded unidentified ReadMarker start time 2023-05-08T17:40:26.872018Z into org.janusgraph.diskstorage.log.kcvs.KCVSLog$MessagePuller@8d8f754
Exception in thread "main" java.lang.IllegalArgumentException: Key must be a user defined key: null
    at com.google.common.base.Preconditions.checkArgument(Preconditions.java:220)
    at org.janusgraph.graphdb.database.management.ManagementSystem$IndexBuilder.addKey(ManagementSystem.java:789)
    at Main.main(Main.java:15)

Process finished with exit code 130

Reproduction

Steps

Create-and-Startup Cassandra [Docker container]
Create-and-Startup JanusGraph [Docker container] (Optional)
Create a Java-Project with Maven this POM.XML
Create-and-Add log4j2.xml, remote-graph.properties, and remote-objects.yaml (Optional)
Create-and-Run Main.java for Indexing using JanusGraphManagement
1. PropertyKey() seems right because its in the latest index document
2. MapReduceIndexManagement() seems wrong because its not in the latest document
3. JanusGraphManagement their example doesn't show a example of how they classed their own interface
Results
1. Expected: Program to run
2. Actually: Runtime Error java.lang.IllegalArgumentException: Key must be a user defined key: null
  1. Removing all the optional steps still produce the same error

Code

│   pom.xml
│
├───src
│   ├───main
│   │   ├───java
│   │   │       Main.java
│   │   │
│   │   └───resources
│   │       │   log4j2.xml

`pom.xml`

    <dependencies>
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-slf4j2-impl</artifactId>
            <version>2.20.0</version>
        </dependency>
        <dependency>
            <groupId>org.janusgraph</groupId>
            <artifactId>janusgraph-cql</artifactId>
            <version>1.0.0-20230504-014643.988c094</version>
        </dependency>
    </dependencies>

`Main.java`

import org.apache.tinkerpop.gremlin.structure.Vertex;
import org.janusgraph.core.JanusGraph;
import org.janusgraph.core.JanusGraphFactory;
import org.janusgraph.core.PropertyKey;
import org.janusgraph.core.schema.JanusGraphManagement;

public class Main {
    public static void main(String[] args) {
        JanusGraph janusGraph = JanusGraphFactory.build().set("storage.backend", "cql").set("storage.hostname", "localhost:9042").open();
        JanusGraphManagement janusGraphManagement = janusGraph.openManagement();
        PropertyKey propertyKey = janusGraphManagement.getPropertyKey("_id");
        janusGraphManagement.buildIndex("_id", Vertex.class).addKey(propertyKey).buildCompositeIndex();
        janusGraphManagement.commit();
        janusGraph.close();
    }
}

Solution

Here's the fix.

PropertyKey propertyKey = janusGraphManagement.getOrCreatePropertyKey("_id");

2023-05-09 08:46:38,617 [INFO] [c.d.o.d.i.c.ContactPoints.main] ::   Contact point localhost:9042 resolves to multiple addresses, will use them all ([localhost/127.0.0.1, localhost/0:0:0:0:0:0:0:1])
2023-05-09 08:46:38,689 [INFO] [c.d.o.d.i.c.DefaultMavenCoordinates.main] ::     DataStax Java driver for Apache Cassandra(R) (com.datastax.oss:java-driver-core) version 4.15.0
2023-05-09 08:46:39,124 [INFO] [c.d.o.d.i.c.t.Clock.JanusGraph Session-admin-0] ::   Using native clock for microsecond precision
2023-05-09 08:46:39,385 [WARN] [c.d.o.d.i.c.l.h.OptionalLocalDcHelper.JanusGraph Session-admin-0] ::     [JanusGraph Session|default] You specified datacenter1 as the local DC, but some contact points are from a different DC: Node(endPoint=localhost/[0:0:0:0:0:0:0:1]:9042, hostId=null, hashCode=7b9f753a)=null; please provide the correct local DC, or check your contact points
2023-05-09 08:46:39,610 [INFO] [o.j.g.i.UniqueInstanceIdRetriever.main] ::   Generated unique-instance-id=c0a8563c11168-rmt-lap-win201
2023-05-09 08:46:39,625 [INFO] [c.d.o.d.i.c.ContactPoints.main] ::   Contact point localhost:9042 resolves to multiple addresses, will use them all ([localhost/127.0.0.1, localhost/0:0:0:0:0:0:0:1])
2023-05-09 08:46:39,651 [INFO] [c.d.o.d.i.c.t.Clock.JanusGraph Session-admin-0] ::   Using native clock for microsecond precision
2023-05-09 08:46:39,693 [WARN] [c.d.o.d.i.c.l.h.OptionalLocalDcHelper.JanusGraph Session-admin-0] ::     [JanusGraph Session|default] You specified datacenter1 as the local DC, but some contact points are from a different DC: Node(endPoint=localhost/[0:0:0:0:0:0:0:1]:9042, hostId=null, hashCode=1ce6602a)=null; please provide the correct local DC, or check your contact points
2023-05-09 08:46:39,707 [INFO] [o.j.d.c.ExecutorServiceBuilder.main] ::  Initiated fixed thread pool of size 40
2023-05-09 08:46:39,818 [INFO] [o.j.g.d.StandardJanusGraph.main] ::  Gremlin script evaluation is disabled
2023-05-09 08:46:39,844 [INFO] [o.j.d.l.k.KCVSLog.main] ::   Loaded unidentified ReadMarker start time 2023-05-09T13:46:39.844155Z into org.janusgraph.diskstorage.log.kcvs.KCVSLog$MessagePuller@ff23ae7

Process finished with exit code 0

There might not be any JanusGraphManagement method like set(), create(), insert(), make(), or add() for new PropertyKeys. But, they've conjoined get-and-create together like making a SQL SELECT-or-CREATE/INSERT or a Java Getter-and-Setter as one method.

Finding-and-realizing this just threw me through a loop.

import org.apache.tinkerpop.gremlin.structure.Vertex;
import org.janusgraph.core.JanusGraph;
import org.janusgraph.core.JanusGraphFactory;
import org.janusgraph.core.PropertyKey;
import org.janusgraph.core.schema.JanusGraphManagement;

public class Main {
    public static void main(String[] args) {
        JanusGraph janusGraph = JanusGraphFactory.build().set("storage.backend", "cql").set("storage.hostname", "localhost:9042").open();
        JanusGraphManagement janusGraphManagement = janusGraph.openManagement();
        PropertyKey propertyKey = janusGraphManagement.getOrCreatePropertyKey("_id");
        janusGraphManagement.buildIndex("_id", Vertex.class).addKey(propertyKey).buildCompositeIndex();
        janusGraphManagement.commit();
        janusGraph.close();
    }
}