How to create a custom reusable type in ElasticSearch?

My json for ElasticSearch schema looks like this :-

{
  "mappings": {
    "properties": {
      "DESCRIPTION_FR": {
        "type": "text",
        "analyzer": "french"
      },
      "FEEDBACK_FR": {
        "type": "text",
        "analyzer": "french"
      },
      "SOURCE_FR": {
        "type": "text",
        "analyzer": "french"
      }
    }
  }
}

There are 100 of properties like this. Replicating a change across all the properties with this approach is redundant and erroneous.

Is there a way in ElasticSearch 7.2 to write custom data type and reuse it in property mapping.

{
  "settings": {
  //definition of custom type "text_fr"
 },
  "mappings": {
    "properties": {
      "DESCRIPTION_FR": {
        "type": "text_fr"
      },
      "FEEDBACK_FR": {
        "type": "text_fr"
      },
      "SOURCE_FR": {
        "type": "text_fr"
      }
    }
  }
}

Yes! What you're after is dynamic mapping templates. More specifically the match feature.

1. Define the target field names with a leading wildcard:

PUT my_index
{
  "mappings": {
    "dynamic_templates": [
      {
        "is_french_text": {
          "match_mapping_type": "*",
          "match": "*_FR",
          "mapping": {
            "type": "text",
            "analyzer": "french"
          }
        }
      }
    ]
  }
}

2. Insert a doc:

POST my_index/_doc
{
  "DESCRIPTION_FR": "je",
  "FEEDBACK_FR": "oui",
  "SOURCE_FR": "je ne sais quoi"
}

3. Verify the dynamically generated mapping:

GET my_index/_mapping