How to access term positions/offsets from Elasticsearch Painless script?

Question

We use AWS Elasticsearch, which support Painless scripting from version 5. I need an access to term positions/offsets in my custom score script.

In old Groovy scripting it worked:

"query": {
    "function_score": {
        "query": {"match_phrase": {"text": "life"} },
        "script_score": {
            "script": {
                "lang": "groovy",
                "inline": "termInfo=_index['text'].get('life', _POSITIONS);"
            }
        },
        "boost_mode": "multiply"
    }
}

But it does not work with Painless. It returns 'compile error'.

The AWS Elasticsearch managed service is good enough if you merely want to store your logs, but it's so restrictive that if you need to do anything more involved you should use another provider. — Val, Feb 22 '17 at 19:03

score 1 · Answer 1 · answered Feb 05 '20 at 10:58

I hope this helps, I wanted scores based on the position of the query text in the document

{
    "query": {
        "bool": {
            "should": [
                {
                    "function_score": {
                        "query": {
                            "match_phrase_prefix": {
                                "field": "query"
                            }
                        },
                        "script_score": {
                            "script": {
                                "lang": "painless",
                                "source": "(params['_source']['field'].toLowerCase().indexOf('query'.toLowerCase())+1)"
                            }
                        },
                        "boost_mode": "max"
                    }
                }
            ]
        }
    }
}

How to access term positions/offsets from Elasticsearch Painless script?

1 Answers1

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