Python – The OrientDB Gremlin server does not work in python

I use orientdb and gremlin server in

python and the gremlin server starts successfully, but when I try to add a vertex to orientdb via gremlin code, it gives me an error.

query = """graph.addVertex(label, "Test", "title", "abc", "title", "abc")"""

The backtracking is as follows

/usr/bin/python3.6 /home/admin-12/Documents/bitbucket/ecodrone/ecodrone/test/test1.py
Traceback (most recent call last):
  File "/home/admin-12/Documents/bitbucket/ecodrone/ecodrone/test/test1.py", line 27, in <module>
    result = execute_query("""graph.addVertex(label, "Test", "title", "abc", "title", "abc")""")
  File "/home/admin-12/Documents/bitbucket/ecodrone/ecodrone/GremlinConnector.py", line 21, in execute_query
    results = future_results.result()
  File "/usr/lib/python3.6/concurrent/futures/_base.py", line 432, in result
    return self.__get_result()
  File "/usr/lib/python3.6/concurrent/futures/_base.py", line 384, in __get_result
    raise self._exception
  File "/home/admin-12/.local/lib/python3.6/site-packages/gremlin_python/driver/resultset.py", line 81, in cb
    f.result()
  File "/usr/lib/python3.6/concurrent/futures/_base.py", line 425, in result
    return self.__get_result()
  File "/usr/lib/python3.6/concurrent/futures/_base.py", line 384, in __get_result
    raise self._exception
  File "/usr/lib/python3.6/concurrent/futures/thread.py", line 56, in run
    result = self.fn(*self.args, **self.kwargs)
  File "/home/admin-12/.local/lib/python3.6/site-packages/gremlin_python/driver/connection.py", line 77, in _receive
    self._protocol.data_received(data, self._results)
  File "/home/admin-12/.local/lib/python3.6/site-packages/gremlin_python/driver/protocol.py", line 106, in data_received
    "{0}: {1}".format(status_code, data["status"]["message"]))
gremlin_python.driver.protocol.GremlinServerError: 599: Error during serialization: Infinite recursion (StackOverflowError) (through reference chain: com.orientechnologies.orient.core.id.ORecordId["record"]->com.orientechnologies.orient.core.record.impl.ODocument["schemaClass"]-> com.orientechnologies.orient.core.metadata.schema.OClassImpl["document"]->com.orientechnologies.orient.core.record.impl.ODocument["owners"]-> com.orientechnologies.orient.core.record.impl.ODocument["owners"]->com.orientechnologies.orient.core.record.impl.ODocument["owners"]-> com.orientechnologies.orient.core.record.impl.ODocument["owners"]->com.orientechnologies.orient.core.record.impl.ODocument["owners"]-> com.orientechnologies.orient.core.record.impl.ODocument["owners"]->com.orientechnologies.orient.core.record.impl.ODocument["owners"]-> com.orientechnologies.orient.core.record.impl.ODocument["owners"]->com.orientechnologies.orient.core.record.impl.ODocument["owners"]-> com.orientechnologies.orient.core.record.impl.ODocument["owners"]->com.orientechnologies.orient.core.record.impl.ODocument["owners"]-> com.orientechnologies.orient.core.record.impl.ODocument["owners"]->com.orientechnologies.orient.core.record.impl.ODocument["owners"]-> com.orientechnologies.orient.core.record.impl.ODocument["owners"]->com.orientechnologies.orient.core.record.impl.ODocument["owners"]-> com.orientechnologies.orient.core.record.impl.ODocument["owners"]->com.orientechnologies.orient.core.record.impl.ODocument["owners"]-> com.orientechnologies.orient.core.record.impl.ODocument["owners"]->com.orientechnologies.orient.core.record.impl.ODocument["owners"]-> com.orientechnologies.orient.core.record.impl.ODocument["owners"]->com.orientechnologies.orient.core.record.impl.ODocument["owners"]-> com.orientechnologies.orient.core.record.impl.ODocument["owners"]->com.orientechnologies.orient.core.record.impl.ODocument["owners"]-> com.orientechnologies.orient.core.record.impl.ODocument["owners"]->com.orientechnologies.orient.core.record.impl.ODocument["owners"]-> com.orientechnologies.orient.core.record.impl.ODocument["owners"]->com.orientechnologies.orient.core.record.impl.ODocument["owners"]-> com.orientechnologies.orient.core.record.impl.ODocument["owners"]->com.orientechnologies.orient.core.record.impl.ODocument["owners"]-> com.orientechnologies.orient.core.record.impl.ODocument["owners"]->com.orientechnologies.orient.core.record.impl.ODocument["owners"]-> com.orientechnologies.orient.core.record.impl.ODocument["owners"]->com.orientechnologies.orient.core.record.impl.ODocument["owners"]-> com.orientechnologies.orient.core.record.impl.ODocument["owners"]->com.orientechnologies.orient.core.record.impl.ODocument["owners"]-> com.orientechnologies.orient.core.record.impl.ODocument["owners"])

Process finished with exit code 1

First of all, I strongly recommend that you do not use the Graph API to do mutations. To do this, prefer the Traversal API and do the following:

g.addV('Test').
  property('title1', 'abc').
  property('title2', 'abc')

Second, I think your error happened because you were returning a Vertex with an ORecordId, which is the vertex identifier, and the Gremlin server doesn’t know what to do with that. I don’t know if OrientDB has a serializer to handle this, but if there is, then you’ll want to add The configuration described in more detail by them to Gremlin Server here – basically, you want to know Does OrientDB expose TinkerPop IORegistry for all custom classes that may be sent back over the network.

If they don’t, then you might want to avoid returning these or converting them yourself. TinkerPop has advised you not to return the full Vertex object, but only the data you need. So instead of using g.V(), use g.V().valueMap('title') or something similar (maybe use the project() step). If you do need a vertex identifier, then you need to convert it to something that the TinkerPop serializer can understand. This can mean something simple:

g.V().has("title1","abc").id().next().toString()