IMPORTANT: No additional bug fixes or documentation updates will be released for this version. For the latest information, see the current release documentation.
« Get transform statistics API Start transforms API »
Elastic Docs ›Elasticsearch Guide [7.3] ›REST APIs ›Transform APIs

Preview transforms API

edit
IMPORTANT: This documentation is no longer updated. Refer to Elastic's version policy and the latest documentation.

Preview transforms API

edit

Previews a transform.

This functionality is in beta and is subject to change. The design and code is less mature than official GA features and is being provided as-is with no warranties. Beta features are not subject to the support SLA of official GA features.

Request

edit

POST _data_frame/transforms/_preview

Prerequisites

edit
  • If the Elasticsearch security features are enabled, you must have manage_data_frame_transforms cluster privileges to use this API. The built-in data_frame_transforms_admin role has these privileges. You must also have read and view_index_metadata privileges on the source index for the transform. For more information, see Security privileges and Built-in roles.

Description

edit

This API generates a preview of the results that you will get when you run the create transforms API with the same configuration. It returns a maximum of 100 results. The calculations are based on all the current data in the source index.

Request body

edit
source

(Required, object) The source configuration, which has the following properties:

index
(Required, string or array) The source indices for the transform. It can be a single index, an index pattern (for example, "myindex*"), or an array of indices (for example, ["index1", "index2"]).
query
(Optional, object) A query clause that retrieves a subset of data from the source index. See Query DSL.
pivot
(Required, object) Defines the pivot function group by fields and the aggregation to reduce the data. See Pivot objects.

Response body

edit
preview
(array) An array of documents. In particular, they are the JSON representation of the documents that would be created in the destination index by the transform.

Examples

edit
POST _data_frame/transforms/_preview
{
  "source": {
    "index": "kibana_sample_data_ecommerce"
  },
  "pivot": {
    "group_by": {
      "customer_id": {
        "terms": {
          "field": "customer_id"
        }
      }
    },
    "aggregations": {
      "max_price": {
        "max": {
          "field": "taxful_total_price"
        }
      }
    }
  }
}

The data that is returned for this example is as follows:

{
  "preview" : [
    {
      "max_price" : 171.0,
      "customer_id" : "10"
    },
    {
      "max_price" : 233.0,
      "customer_id" : "11"
    },
    {
      "max_price" : 200.0,
      "customer_id" : "12"
    }
    ...
  ],
  "mappings": {
    "properties": {
      "max_price": {
        "type": "double"
      },
      "customer_id": {
        "type": "keyword"
      }
    }
  }
}
« Get transform statistics API Start transforms API »