1.4.0 failed to compile and run native script score function

[andyxukq]

Hi y'all,

After upgrading to 1.4.0, I failed to compile my native(Java) score functions which worked well with 1.3.4.
The first issue I ran into is that my function extended AbstractDoubleSearchScript and call score() to get document score from Lucene, apparently it won't work now with 1.4.0.

I wonder if any of you could tell me which method should be called to get the original score of one document. An example of my function looks like:

public class BasicScorer extends AbstractDoubleSearchScript {

  public static final String NAME = "basic-scorer";

  public static class Factory implements NativeScriptFactory {
    @Override
    public ExecutableScript newScript(@Nullable Map<String, Object> params) {
      return new BasicScorer();
  }

  private BasicScorer() {
  }

  @Override
  public double runAsDouble() {
      return score() * ((ScriptDocValues.Doubles) doc().get("rank")).getValue();
  }
}

The second issue is when I just remove the 'score()' method and query ElasticSearch with following parameter:

...
     "script_score": {
        "script": "basic-scorer",
        "lang": "native"
      }
...

following error was logged:

    at org.elasticsearch.search.query.QueryParseElement.parse(QueryParseElement.java:33)
    at org.elasticsearch.search.SearchService.parseSource(SearchService.java:665)
    ... 9 more
Caused by: java.lang.UnsupportedOperationException
    at org.elasticsearch.script.AbstractSearchScript.setScorer(AbstractSearchScript.java:104)
    at org.elasticsearch.common.lucene.search.function.ScriptScoreFunction.<init>(ScriptScoreFunction.java:86)

I noticed there were some groovy script function changes, but I don't think that should affect the interface of native score function.

Regards,
Andy

[dccmx]

Same problem here, and I can not find a way (efficient way) to get the score lucene provided within a native score script.

[clintongormley]

It looks like it is to do with this change: #7819

@brwe can you shed more light here please?

[kilnyy]

I think I have the same issue, I wrote my plugin with the instruction in this repo:
https://github.com/imotov/elasticsearch-native-script-example
and also got UnsupportedOperationException in the log.

[noamt]

I too suffer from the issue

[rjernst]

In 1.3 and before, there was a weird dual API for setting the score (see #6864). The score() function was removed there.

To access the score from a native script, you should @Override setScorer(Scorer) and call scorer.score() on when you want the score.

[rjernst]

After looking at this a little more, the original intention was the score could be accessed with doc().score(), but that was removed with #7819. I've opened #8416 to add back score() for AbstractSearchScript.

[imotov]

@kilnyy, @noamt elasticsearch-native-script-example is updated with a temporary work-around until 1.4.1 is released.

[noamt]

Cheers!