Analysis Predicate Context [painless-analysis-predicate-context]

Use a painless script to determine whether or not the current token in an analysis chain matches a predicate.

:::{tip} This is an advanced feature for customizing text analysis and token filtering. To learn more, refer to Text analysis. :::

Variables

params (Map, read-only) : User-defined parameters passed in as part of the query.

token.term (CharSequence, read-only) : The characters of the current token

token.position (int, read-only) : The position of the current token

token.positionIncrement (int, read-only) : The position increment of the current token

token.positionLength (int, read-only) : The position length of the current token

token.startOffset (int, read-only) : The start offset of the current token

token.endOffset (int, read-only) : The end offset of the current token

token.type (String, read-only) : The type of the current token

token.keyword (boolean, read-only) : Whether or not the current token is marked as a keyword

Return

boolean : Whether or not the current token matches the predicate

API

The standard Painless API is available.

Example

To run the example, first install the eCommerce sample data.

This example ensures that only properly formatted SKUs are processed. The analyzer checks that SKU codes start with "ZO" and are exactly thirteen characters long, filtering out malformed or invalid product codes that could break inventory systems or search functionality.

PUT sku_analysis
{
  "settings": {
    "analysis": {
      "analyzer": {
        "sku_search_analyzer": {
          "tokenizer": "whitespace",
          "filter": [
            "sku_validator"
          ]
        }
      },
      "filter": {
        "sku_validator": {
          "type": "predicate_token_filter",
          "script": {
            "source": """
              return token.term.length() == 12 && token.term.toString().startsWith('ZO');
            """
          }
        }
      }
    }
  }
}

Test it using the following request:

GET sku_analysis/_analyze
{
  "analyzer": "sku_search_analyzer",
  "text": "ZO0240302403 ZO0236402364 INVALID123 SHORT AB1234567890123"
}

Result:

{
  "tokens": [
    {
      "token": "ZO0240302403",
      "start_offset": 0,
      "end_offset": 12,
      "type": "word",
      "position": 0
    },
    {
      "token": "ZO0236402364",
      "start_offset": 13,
      "end_offset": 25,
      "type": "word",
      "position": 1
    }
  ]
}