_meta field

A mapping type can have custom meta data associated with it. These are not used at all by Elasticsearch, but can be used to store application-specific metadata, such as the class that a document belongs to:

 PUT my-index-000001 {
  "mappings": {
    "_meta": { 1
      "class": "MyApp::User",
      "version": {
        "min": "1.0",
        "max": "1.3"
      }
    }
  }
}

1. This _meta info can be retrieved with the GET mapping API.

The _meta field can be updated on an existing type using the update mapping API:

 PUT my-index-000001/_mapping {
  "_meta": {
    "class": "MyApp2::User3",
    "version": {
      "min": "1.3",
      "max": "1.5"
    }
  }
}