Error while migrating data from Neo4j to OrientDb - neo4j

Question

I'm getting the following error while importing the data from Neo4j.
OrientDb server is not running as per the documentation.
[cloud_user#xxxxxxx bin]$ ./orientdb-neo4j-importer.sh -neo4jlibdir ~/neo4j-community-3.4.7/lib/ -neo4jdbdir ~/backup_files/graph.db/
Neo4j to OrientDB Importer v.3.0.10 - Veloce (build eac0654847df662ca03b45a6a5efa5eadd229ca5, branch 3.0.x) - Copyrights (c) 2017 OrientDB LTD
WARNING: 'o' option not found. Defaulting to 'false'.
WARNING: 'i' option not found. Defaulting to 'false'.
WARNING: 'odbdir' option not found. Defaulting to '/opt/orientdb/databases/neo4j_import'.
Please make sure that there are no running servers on:
'/home/cloud_user/backup_files/graph.db' (Neo4j)
and:
'/opt/orientdb/databases/neo4j_import' (OrientDB)
Initializing Neo4j...Done
Initializing OrientDB...Exception in thread "main" java.lang.NoClassDefFoundError: com/tinkerpop/blueprints/impls/orient/OrientGraphFactory
at com.orientechnologies.orient.neo4jimporter.ONeo4jImporterInitializer.invoke(ONeo4jImporterInitializer.java:94)
at com.orientechnologies.orient.neo4jimporter.ONeo4jImporter.execute(ONeo4jImporter.java:108)
at com.orientechnologies.orient.neo4jimporter.ONeo4jImporterMain.main(ONeo4jImporterMain.java:25)
Caused by: java.lang.ClassNotFoundException: com.tinkerpop.blueprints.impls.orient.OrientGraphFactory
at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
... 3 more
[cloud_user#xxxxxxx bin]$

Answer 1

I struggled for more than 2 hours trying to import data from Neo4j to Orientdb. The documentation is quite sloppy.
You can solve this issue by downloading the jar- orientdb-graphdb-*.jar into lib folder. However, you still might face the other issues of missing classes.
Downloading jars below helped to resolve such issues:
blueprints-core-*.jar
gremlin-groovy-3.3.4.jar
Let me know if you still face class missing issues.
Hope that saves someone's time.

Answer 2

OrientDB does not contain all of the necessary libraries it needs to perform this task by default. Often, you can define submodules to be imported in a pom file, but if you aren't using a Java application, then you need to import these libraries yourself into the lib/ folder of your OrientDB home directory.
To get the importer to work download the following JAR files and move them into the lib/ folder:
- orientdb-graphdb
- Tinkerpop Blueprints Core
- Gremlin Groovy