原文地址: https://www.elastic.co/guide/en/elasticsearch/reference/7.7/put-transform.html, 原文档版权归 www.elastic.co 所有

Create transform APIedit

Instantiates a transform.

Requestedit

PUT _transform/<transform_id>

Prerequisitesedit

If the Elasticsearch security features are enabled, you must have the following built-in roles and privileges:

  • transform_admin
  • kibana_admin (UI only)
  • source index: read, view_index_metadata
  • destination index: read, create_index, manage and index
  • cluster: monitor (UI only)

For more information, see Security privileges and Built-in roles.

Descriptionedit

This API defines a transform, which copies data from source indices, transforms it, and persists it into an entity-centric destination index. The entities are defined by the set of group_by fields in the pivot object. You can also think of the destination index as a two-dimensional tabular data structure (known as a data frame). The ID for each document in the data frame is generated from a hash of the entity, so there is a unique row per entity. For more information, see Transforming data.

When the transform is created, a series of validations occur to ensure its success. For example, there is a check for the existence of the source indices and a check that the destination index is not part of the source index pattern. You can use the defer_validation parameter to skip these checks.

Deferred validations are always run when the transform is started, with the exception of privilege checks. When Elasticsearch security features are enabled, the transform remembers which roles the user that created it had at the time of creation and uses those same roles. If those roles do not have the required privileges on the source and destination indices, the transform fails when it attempts unauthorized operations.

You must use Kibana or this API to create a transform. Do not put a transform directly into any .transform-internal* indices using the Elasticsearch index API. If Elasticsearch security features are enabled, do not give users any privileges on .transform-internal* indices. If you used transforms prior 7.5, also do not give users any privileges on .data-frame-internal* indices.

Path parametersedit

<transform_id>
(Required, string) Identifier for the transform. This identifier can contain lowercase alphanumeric characters (a-z and 0-9), hyphens, and underscores. It must start and end with alphanumeric characters.

Query parametersedit

defer_validation
(Optional, boolean) When true, deferrable validations are not run. This behavior may be desired if the source index does not exist until after the transform is created.

Request bodyedit

description
(Optional, string) Free text description of the transform.
dest

(Required, object) The destination for the transform.

Properties of dest
index
(Required, string) The destination index for the transform.
pipeline
(Optional, string) The unique identifier for a pipeline.
frequency
(Optional, time units) The interval between checks for changes in the source indices when the transform is running continuously. Also determines the retry interval in the event of transient failures while the transform is searching or indexing. The minimum value is 1s and the maximum is 1h. The default value is 1m.
pivot

(Required, object) The method for transforming the data. These objects define the pivot function group by fields and the aggregation to reduce the data.

Properties of pivot
aggregations or aggs

(Required, object) Defines how to aggregate the grouped data. The following composite aggregations are supported:

Transforms support a subset of the functionality in composite aggregations. See Limitations.

group_by

(Required, object) Defines how to group the data. More than one grouping can be defined per pivot. The following groupings are supported:

max_page_search_size
(Optional, integer) Defines the initial page size to use for the composite aggregation for each checkpoint. If circuit breaker exceptions occur, the page size is dynamically adjusted to a lower value. The minimum value is 10 and the maximum is 10,000. The default value is 500.
source

(Required, object) The source of the data for the transform.

Properties of source
index
(Required, string or array) The source indices for the transform. It can be a single index, an index pattern (for example, "myindex*"), an array of indices (for example, ["index1", "index2"]), or an array of index patterns (for example, ["myindex1-*", "myindex2-*"].
query
(Optional, object) A query clause that retrieves a subset of data from the source index. See Query DSL.
sync

(Optional, object) Defines the properties transforms require to run continuously.

Properties of sync
time

(Required, object) Specifies that the transform uses a time field to synchronize the source and destination indices.

Properties of time
delay
(Optional, time units) The time delay between the current time and the latest input data time. The default value is 60s.
field

(Required, string) The date field that is used to identify new documents in the source.

In general, it’s a good idea to use a field that contains the ingest timestamp. If you use a different field, you might need to set the delay such that it accounts for data transmission delays.

Examplesedit

PUT _transform/ecommerce_transform
{
  "source": {
    "index": "kibana_sample_data_ecommerce",
    "query": {
      "term": {
        "geoip.continent_name": {
          "value": "Asia"
        }
      }
    }
  },
  "pivot": {
    "group_by": {
      "customer_id": {
        "terms": {
          "field": "customer_id"
        }
      }
    },
    "aggregations": {
      "max_price": {
        "max": {
          "field": "taxful_total_price"
        }
      }
    }
  },
  "description": "Maximum priced ecommerce data by customer_id in Asia",
  "dest": {
    "index": "kibana_sample_data_ecommerce_transform",
    "pipeline": "add_timestamp_pipeline"
  },
  "frequency": "5m",
  "sync": {
    "time": {
      "field": "order_date",
      "delay": "60s"
    }
  }
}

When the transform is created, you receive the following results:

{
  "acknowledged" : true
}