Gremlin python

This mini-tutorial is inspired by this stackoverflow question

The goal is to get access to an apache tinkerpop/gremlin graph database via Python.

Prerequisites

1. Java
2. Python
3. Gremlin-Server
4. Gremlin-Console (for debugging)

Installing Java

sudo apt-get install openjdk-8-jre 
java -version
openjdk version "1.8.0_222"
OpenJDK Runtime Environment (build 1.8.0_222-8u222-b10-1ubuntu1~18.04.1-b10)
OpenJDK 64-Bit Server VM (build 25.222-b10, mixed mode)

Installing Python and Pip

sudo apt install python2.7
python --version
Python 2.7.15+
sudo apt install python-pip
pip --version
pip 9.0.1 from /usr/lib/python2.7/dist-packages (python 2.7)

Installing Gremlin Server and Console

• http://tinkerpop.apache.org/downloads.html

Trial script

#!/bin/bash
# WF 2019-09-17
# test gremlin-python

# see https://stackoverflow.com/questions/57936915/how-do-i-get-gremlin-python-with-gremlin-server-3-4-3-to-work
version=3.4.3
mirror=http://mirror.dkd.de/apache/tinkerpop/$version
gsd=apache-tinkerpop-gremlin-server-${version}
gcd=apache-tinkerpop-gremlin-console-${version}

# check that the given program is installed
checkinstalled() {
  local l_prg="$1"
  local l_version="$2"
  local l_package="$3"
  which $l_prg
  if [ $? -ne 0 ]
  then
    echo "$l_prg is not available - shall i install it from $l_package y/n?"
    read x
    case $x in
      y) sudo apt-get install $l_package;;
      *) echo "aborting ..."
         exit 1;;
    esac
  fi
  $l_prg $l_version
}

install() {
  echo "checking prerequisites ..."
  checkinstalled java "-version" "openjdk-8-jre"
  checkinstalled python "--version" "python2.7"
  checkinstalled pip "--version" "python-pip"

  for d in $gsd $gcd
  do
    if [ ! -d $d ]
    then
      zip=$d-bin.zip
      if [ ! -f $zip ]
      then
        echo "downloading $zip"
        curl -s $mirror/$zip -o $zip
      else
        echo "$zip already downloaded"
      fi
      echo "unzipping $zip"
      unzip $zip
    else
      echo "$d already unzipped"
    fi
  done
}

# commandline option
while [  "$1" != ""  ]
do
  option=$1
  shift
  case $option in
    -i|--install)
      install;;
    -s|--server)
      echo "starting gremlin-server ..."
      #conf=$(realpath $gsd/conf/gremlin-server-modern-py.yaml)
      conf=$(realpath $gsd/conf/gremlin-server-modern.yaml)
      $gsd/bin/gremlin-server.sh $conf
      ;;
    -c|--console)
      echo "starting gremlin-console ..."
      $gcd/bin/gremlin.sh
      ;;
    -h|--help)
      usage;;
    *)
      usage;;
  esac
done

Trial result

# install needed parts
./run -i
checking prerequisites ...
/usr/bin/java
java version "1.8.0_172"
Java(TM) SE Runtime Environment (build 1.8.0_172-b11)
Java HotSpot(TM) 64-Bit Server VM (build 25.172-b11, mixed mode)
/usr/bin/python
Python 2.7.5
/opt/local/bin/pip
pip 19.2.3 from /opt/local/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/pip (python 3.7)
apache-tinkerpop-gremlin-server-3.4.3 already unzipped
apache-tinkerpop-gremlin-console-3.4.3 already unzipped
# run gremlin server
./run -s
starting gremlin-server ...
[INFO] GremlinServer - 3.4.3
         \,,,/
         (o o)
-----oOOo-(3)-oOOo-----

[INFO] GremlinServer - Configuring Gremlin Server from /Users/wf/source/python/gremlintest/apache-tinkerpop-gremlin-server-3.4.3/conf/gremlin-server-modern.yaml
[INFO] MetricManager - Configured Metrics Slf4jReporter configured with interval=180000ms and loggerName=org.apache.tinkerpop.gremlin.server.Settings$Slf4jReporterMetrics
[INFO] DefaultGraphManager - Graph [graph] was successfully configured via [conf/tinkergraph-empty.properties].
[INFO] ServerGremlinExecutor - Initialized Gremlin thread pool.  Threads in pool named with pattern gremlin-*
[INFO] ServerGremlinExecutor - Initialized GremlinExecutor and preparing GremlinScriptEngines instances.
[INFO] ServerGremlinExecutor - Initialized gremlin-groovy GremlinScriptEngine and registered metrics
[INFO] ServerGremlinExecutor - A GraphTraversalSource is now bound to [g] with graphtraversalsource[tinkergraph[vertices:0 edges:0], standard]
[INFO] OpLoader - Adding the standard OpProcessor.
[INFO] OpLoader - Adding the session OpProcessor.
[INFO] OpLoader - Adding the traversal OpProcessor.
[INFO] TraversalOpProcessor - Initialized cache for TraversalOpProcessor with size 1000 and expiration time of 600000 ms
[INFO] GremlinServer - Executing start up LifeCycleHook
[INFO] Logger$info - Loading 'modern' graph data.
[INFO] GremlinServer - idleConnectionTimeout was set to 0 which resolves to 0 seconds when configuring this value - this feature will be disabled
[INFO] GremlinServer - keepAliveInterval was set to 0 which resolves to 0 seconds when configuring this value - this feature will be disabled
[WARN] AbstractChannelizer - The org.apache.tinkerpop.gremlin.driver.ser.GryoMessageSerializerV3d0 serialization class is deprecated.
[INFO] AbstractChannelizer - Configured application/vnd.gremlin-v3.0+gryo with org.apache.tinkerpop.gremlin.driver.ser.GryoMessageSerializerV3d0
[WARN] AbstractChannelizer - The org.apache.tinkerpop.gremlin.driver.ser.GryoMessageSerializerV3d0 serialization class is deprecated.
[INFO] AbstractChannelizer - Configured application/vnd.gremlin-v3.0+gryo-stringd with org.apache.tinkerpop.gremlin.driver.ser.GryoMessageSerializerV3d0
[INFO] AbstractChannelizer - Configured application/vnd.gremlin-v3.0+json with org.apache.tinkerpop.gremlin.driver.ser.GraphSONMessageSerializerV3d0
[INFO] AbstractChannelizer - Configured application/json with org.apache.tinkerpop.gremlin.driver.ser.GraphSONMessageSerializerV3d0
[INFO] AbstractChannelizer - Configured application/vnd.graphbinary-v1.0 with org.apache.tinkerpop.gremlin.driver.ser.GraphBinaryMessageSerializerV1
[INFO] AbstractChannelizer - Configured application/vnd.graphbinary-v1.0-stringd with org.apache.tinkerpop.gremlin.driver.ser.GraphBinaryMessageSerializerV1
[INFO] GremlinServer$1 - Gremlin Server configured with worker thread pool of 1, gremlin pool of 2 and boss thread pool of 1.
[INFO] GremlinServer$1 - Channel started at port 8182.
# and in an other console
./run -c
starting gremlin-console ...

         \,,,/
         (o o)
-----oOOo-(3)-oOOo-----
plugin activated: tinkerpop.server
plugin activated: tinkerpop.utilities
plugin activated: tinkerpop.tinkergraph
gremlin> g=traversal().withRemote(DriverRemoteConnection('ws://localhost:8182/gremlin','g'))
No signature of method: groovysh_evaluate.DriverRemoteConnection() is applicable for argument types: (String, String) values: [ws://localhost:8182/gremlin, g]
Type ':help' or ':h' for help.