ScriptScoreQuery for Custom JavaScript Scoring

ScriptScoreQuery runs a base query first and then replaces each hit score with the result of a JavaScript function.

That makes it useful when you want to combine lexical relevance with a custom formula.

Basic example

import {
  DocumentIndex,
  NumericFieldIndex,
  ScriptScoreQuery,
  TermQuery,
  TextFieldIndex
} from "@tryformation/querylight-ts";

const index = new DocumentIndex({
  popularity: new NumericFieldIndex(),
  title: new TextFieldIndex()
});

index.index({ id: "1", fields: { popularity: ["5"], title: ["querylight"] } });
index.index({ id: "2", fields: { popularity: ["20"], title: ["querylight"] } });

const hits = index.searchRequest({
  query: new ScriptScoreQuery(
    new TermQuery("title", "querylight"),
    ({ score, numericValue }) => score * (numericValue("popularity") ?? 1)
  )
});

Available helpers

The scoring function receives:

• score: the base score from the wrapped query
• document
• documentIndex
• values(field)
• value(field)
• numericValues(field)
• numericValue(field)

Good uses

• Multiply lexical relevance by a popularity score.
• Blend exact-match score with freshness or quality.
• Apply a custom ranking formula without building a new query class.

Notes

• The wrapped query decides which documents are candidates.
• Non-finite or non-positive script results are dropped.
• Keep the function deterministic and easy to reason about.