In storm, how to specify specific version of python

Question

I'm trying to run a topology in storm that makes calls to python (ex: WordCountTopology) but I encounter errors that are related to the fact that python3.5.2 is the default python on my server (errors are about the old/new syntax of print command). How to specify to storm to use python2.7 instead of python3.5? Setting a python alias to python2.7 does not change anything. Any help appreciated.

Answer 1

I guess you're using ShellSpout / ShellBolt. In constructor you can specify the command to execute subprocess, so you can explicitly set command to python2.7.

For example,

  public static class SplitSentence extends ShellBolt implements IRichBolt {

    public SplitSentence() {
      super("python", "splitsentence.py");
    }

    @Override
    public void declareOutputFields(OutputFieldsDeclarer declarer) {
      declarer.declare(new Fields("word"));
    }

    @Override
    public Map<String, Object> getComponentConfiguration() {
      return null;
    }
  }

You can replace "python" to which python2.7 is placed. All supervisor nodes should have file to that place.