[TINKERPOP-2370] Unable to set the server side script timeout in gremlin-python

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Duplicate
• Affects Version/s: 3.4.6
• Component/s: python
• Environment: python
• Assignee: Unassigned
• Reporter: Janne Pänkälä
• Created: 12/May/20 17:52
• Updated: 12/May/20 18:32
• Resolved: 12/May/20 18:32

Description

Currently one can set timeLimit() to limit how long query will run in the backend.

This however has limitation that one cannot know if query was completed or not the server will just stop executing it and return whatever it has found by then.

 

Server has query timeout and when that triggers one receives TimeLimitExceededException.

There is a possibility to set the time limit PER query (or per connection?) by using 
evaluationTimeout (or scriptEvaluationTimeout in older version)
 
It would appear that these are read in the server at the TraversalOpProcessor.java:166
and they COULD be set in gremlin_python/driver/client.py:119 along with 'gremlin' and 'aliases'
 
I tried a minor mod
 
message = request.RequestMessage(
  processor='traversal', op='bytecode',
  args=

{'gremlin': message,      'aliases': \{'g': self._traversal_source}

,
     'evaluationTimeout': 1000,
     'scriptEvaluationTimeout': 1000,
})
 
Against AWS Neptune and that seemed to work out properly.
 
Here it would be easy to read in os.environ.get('ARGS_EVAL_TIMEOUT') but that would make python library function differently from Java library.
 
 
I tried to get it working with some variations of 
 
return g.withStrategies(OptionsStrategy(options={"scriptEvaluationTimeout": 300, "evaluationTimeout": 300})).with_("scriptEvaluationTimeout", 300).with_("evaluationTimeout", 300).V().hasLabel('TestLabel').count()
 
But closer inspection of the client.py implementation woke me to the fact that there just is no way to provide additional 'args' to the connection for TraversalOpProsessor to interpret.
 
I could make a PR for this, but I am not certain as how this implementation would be preferred to happen.
 
 
References.
https://docs.aws.amazon.com/neptune/latest/userguide/best-practices-gremlin-java-per-query-timeout.html
https://github.com/apache/tinkerpop/blob/master/docs/src/reference/gremlin-variants.asciidoc
 
 

Issue Links

• duplicates: TINKERPOP-2296 Per query timeout not working from Python