opensearch-docs-cn/docs/im/index-transforms/transforms-apis.md

---
layout: default
title: Transforms APIs
nav_order: 45
parent: Index transforms
grand_parent: Index management
has_toc: true
---

# Transforms APIs

Aside from using OpenSearch Dashboards, you can also use the REST API to create, start, stop, and complete other operations relative to transform jobs.

#### Table of contents
- TOC
{:toc}

## Create a transform job

Creates a transform job.

**Sample Request**

```json
PUT _plugins/_transform/<transform_id>

{
  "transform": {
  "enabled": true,
  "schedule": {
    "interval": {
    "period": 1,
    "unit": "Minutes",
    "start_time": 1602100553
    }
  },
  "description": "Sample transform job",
  "source_index": "sample_index",
  "target_index": "sample_target",
  "data_selection_query": {
    "match_all": {}
  },
  "page_size": 1,
  "groups": [
    {
    "terms": {
      "source_field": "customer_gender",
      "target_field": "gender"
    }
    },
    {
    "terms": {
      "source_field": "day_of_week",
      "target_field": "day"
    }
    }
  ],
  "aggregations": {
    "quantity": {
    "sum": {
      "field": "total_quantity"
    }
    }
  }
  }
}
```

**Sample Response**

```json
{
  "_id": "sample",
  "_version": 7,
  "_seq_no": 13,
  "_primary_term": 1,
  "transform": {
    "transform_id": "sample",
    "schema_version": 7,
    "schedule": {
      "interval": {
        "start_time": 1621467964243,
        "period": 1,
        "unit": "Minutes"
      }
    },
    "metadata_id": null,
    "updated_at": 1621467964243,
    "enabled": true,
    "enabled_at": 1621467964243,
    "description": "Sample transform job",
    "source_index": "sample_index",
    "data_selection_query": {
      "match_all": {
        "boost": 1.0
      }
    },
    "target_index": "sample_target",
    "roles": [],
    "page_size": 1,
    "groups": [
      {
        "terms": {
          "source_field": "customer_gender",
          "target_field": "gender"
        }
      },
      {
        "terms": {
          "source_field": "day_of_week",
          "target_field": "day"
        }
      }
    ],
    "aggregations": {
      "quantity": {
        "sum": {
          "field": "total_quantity"
        }
      }
    }
  }
}
```
You can specify the following options in the HTTP request body:

Option | Data Type | Description | Required
:--- | :--- | :--- | :---
enabled | Boolean | If true, the transform job is enabled at creation. | No
schedule | JSON | The schedule the transform job runs on. | Yes
start_time | Integer | The Unix epoch time of the transform job's start time. | Yes
description | String | Describes the transform job. | No
metadata_id | String | Any metadata to be associated with the transform job. | No
source_index | String | The source index whose data to transform. | Yes
target_index | String | The target index the newly transformed data is added into. You can create a new index or update an existing one. | Yes
data_selection_query | JSON | The query DSL to use to filter a subset of the source index for the transform job. See [query DSL](../../../opensearch/query-dsl) for more information. | Yes
page_size | Integer | The number of fields to transform at a time. Higher number means higher performance but requires more memory and can cause higher latency. (Default: 1) | Yes
groups | Array | Specifies the grouping(s) to use in the transform job. Supported groups are `terms`, `histogram`, and `date_histogram`. For more information, see [Bucket Aggregations](../../../opensearch/bucket-agg). | Yes if not using aggregations
source_field | String | The field(s) to transform | Yes
aggregations | JSON | The aggregations to use in the transform job. Supported aggregations are: `sum`, `max`, `min`, `value_count`, `avg`, `scripted_metric`, and `percentiles`. For more information, see [Metric Aggregations](../../../opensearch/metric-agg). | Yes if not using groups

## Update a transform job

Updates a transform job if `transform_id` already exists.

**Sample Request**

```json
PUT _plugins/_transform/<transform_id>

{
  "transform": {
  "enabled": true,
  "schedule": {
    "interval": {
    "period": 1,
    "unit": "Minutes",
    "start_time": 1602100553
    }
  },
  "description": "Sample transform job",
  "source_index": "sample_index",
  "target_index": "sample_target",
  "data_selection_query": {
    "match_all": {}
  },
  "page_size": 1,
  "groups": [
    {
    "terms": {
      "source_field": "customer_gender",
      "target_field": "gender"
    }
    },
    {
    "terms": {
      "source_field": "day_of_week",
      "target_field": "day"
    }
    }
  ],
  "aggregations": {
    "quantity": {
    "sum": {
      "field": "total_quantity"
    }
    }
  }
  }
}
```

**Sample Response**

```json
{
  "_id": "sample",
  "_version": 2,
  "_seq_no": 14,
  "_primary_term": 1,
  "transform": {
    "transform_id": "sample",
    "schema_version": 7,
    "schedule": {
      "interval": {
        "start_time": 1602100553,
        "period": 1,
        "unit": "Minutes"
      }
    },
    "metadata_id": null,
    "updated_at": 1621889843874,
    "enabled": true,
    "enabled_at": 1621889843874,
    "description": "Sample transform job",
    "source_index": "sample_index",
    "data_selection_query": {
      "match_all": {
        "boost": 1.0
      }
    },
    "target_index": "sample_target",
    "roles": [],
    "page_size": 1,
    "groups": [
      {
        "terms": {
          "source_field": "customer_gender",
          "target_field": "gender"
        }
      },
      {
        "terms": {
          "source_field": "day_of_week",
          "target_field": "day"
        }
      }
    ],
    "aggregations": {
      "quantity": {
        "sum": {
          "field": "total_quantity"
        }
      }
    }
  }
}
```

The `Update` operation supports the following URL parameters:

Parameter | Description | Required
:---| :--- | :---
`if_seq_no` | Only perform the transform operation if the last operation that changed the transform job has the specified sequence number. | No
`if_primary_term` | Only perform the transform operation if the last operation that changed the transform job has the specified sequence term. | No

## Get a transform job's details

Returns a transform job's details.

**Sample Request**

```json
GET _plugins/_transform/<transform_id>
```

**Sample Response**

```json
{
  "_id": "sample",
  "_version": 7,
  "_seq_no": 13,
  "_primary_term": 1,
  "transform": {
    "transform_id": "sample",
    "schema_version": 7,
    "schedule": {
      "interval": {
        "start_time": 1621467964243,
        "period": 1,
        "unit": "Minutes"
      }
    },
    "metadata_id": null,
    "updated_at": 1621467964243,
    "enabled": true,
    "enabled_at": 1621467964243,
    "description": "Sample transform job",
    "source_index": "sample_index",
    "data_selection_query": {
      "match_all": {
        "boost": 1.0
      }
    },
    "target_index": "sample_target",
    "roles": [],
    "page_size": 1,
    "groups": [
      {
        "terms": {
          "source_field": "customer_gender",
          "target_field": "gender"
        }
      },
      {
        "terms": {
          "source_field": "day_of_week",
          "target_field": "day"
        }
      }
    ],
    "aggregations": {
      "quantity": {
        "sum": {
          "field": "total_quantity"
        }
      }
    }
  }
}
```

You can also get details of all transform jobs by omitting `transform_id`.

**Sample Request**

```json
GET _plugins/_transform/<transform_id>
```

**Sample Response**

```json
{
  "total_transforms": 1,
  "transforms": [
    {
      "_id": "sample",
      "_seq_no": 13,
      "_primary_term": 1,
      "transform": {
        "transform_id": "sample",
        "schema_version": 7,
        "schedule": {
          "interval": {
            "start_time": 1621467964243,
            "period": 1,
            "unit": "Minutes"
          }
        },
        "metadata_id": null,
        "updated_at": 1621467964243,
        "enabled": true,
        "enabled_at": 1621467964243,
        "description": "Sample transform job",
        "source_index": "sample_index",
        "data_selection_query": {
          "match_all": {
            "boost": 1.0
          }
        },
        "target_index": "sample_target",
        "roles": [],
        "page_size": 1,
        "groups": [
          {
            "terms": {
              "source_field": "customer_gender",
              "target_field": "gender"
            }
          },
          {
            "terms": {
              "source_field": "day_of_week",
              "target_field": "day"
            }
          }
        ],
        "aggregations": {
          "quantity": {
            "sum": {
              "field": "total_quantity"
            }
          }
        }
      }
    }
  ]
}
```

You can specify these options as the `GET` API operation’s URL parameters to filter results:

Parameter | Description | Required
:--- | :--- | :---
from | The starting index to search from. (Default: 0) | No
size | Specifies the amount of results to return (Default: 10) | No
search |The search term to use to filter results. | No
sortField | The field to sort results with. | No
sortDirection | Specifies the direction to sort results in. Can be `ASC` or `DESC`. (Default: ASC) | No

For example, this request returns two results starting from the eighth index.

**Sample Request**

```json
GET _plugins/_transform?size=2&from=8
```

**Sample Response**

```json
{
  "total_transforms": 18,
  "transforms": [
    {
      "_id": "sample8",
      "_seq_no": 93,
      "_primary_term": 1,
      "transform": {
        "transform_id": "sample8",
        "schema_version": 7,
        "schedule": {
          "interval": {
            "start_time": 1622063596812,
            "period": 1,
            "unit": "Minutes"
          }
        },
        "metadata_id": "y4hFAB2ZURQ2dzY7BAMxWA",
        "updated_at": 1622063657233,
        "enabled": false,
        "enabled_at": null,
        "description": "Sample transform job",
        "source_index": "sample_index3",
        "data_selection_query": {
          "match_all": {
            "boost": 1.0
          }
        },
        "target_index": "sample_target3",
        "roles": [],
        "page_size": 1,
        "groups": [
          {
            "terms": {
              "source_field": "customer_gender",
              "target_field": "gender"
            }
          },
          {
            "terms": {
              "source_field": "day_of_week",
              "target_field": "day"
            }
          }
        ],
        "aggregations": {
          "quantity": {
            "sum": {
              "field": "total_quantity"
            }
          }
        }
      }
    },
    {
      "_id": "sample9",
      "_seq_no": 98,
      "_primary_term": 1,
      "transform": {
        "transform_id": "sample9",
        "schema_version": 7,
        "schedule": {
          "interval": {
            "start_time": 1622063598065,
            "period": 1,
            "unit": "Minutes"
          }
        },
        "metadata_id": "x8tCIiYMTE3veSbIJkit5A",
        "updated_at": 1622063658388,
        "enabled": false,
        "enabled_at": null,
        "description": "Sample transform job",
        "source_index": "sample_index4",
        "data_selection_query": {
          "match_all": {
            "boost": 1.0
          }
        },
        "target_index": "sample_target4",
        "roles": [],
        "page_size": 1,
        "groups": [
          {
            "terms": {
              "source_field": "customer_gender",
              "target_field": "gender"
            }
          },
          {
            "terms": {
              "source_field": "day_of_week",
              "target_field": "day"
            }
          }
        ],
        "aggregations": {
          "quantity": {
            "sum": {
              "field": "total_quantity"
            }
          }
        }
      }
    }
  ]
}
```

## Start a transform job

Transform jobs created using the API are automatically enabled, but if you ever need to enable a job, you can use the `start` API operation.

**Sample Request**

```json
POST _plugins/_transform/<transform_id>/_start
```

**Sample Response**

```json
{
  "acknowledged": true
}
```

## Stop a transform job

Stops/disables a transform job.

**Sample Request**

```json
POST _plugins/_transform/<transform_id>/_stop
```

**Sample Response**

```json
{
  "acknowledged": true
}
```

## Get the status of a transform job

Returns the status and metadata of a transform job.

**Sample Request**

```json
GET _plugins/_transform/<transform_id>/_explain
```

**Sample Response**

```json
{
  "sample": {
    "metadata_id": "PzmjweME5xbgkenl9UpsYw",
    "transform_metadata": {
      "transform_id": "sample",
      "last_updated_at": 1621883525873,
      "status": "finished",
      "failure_reason": "null",
      "stats": {
        "pages_processed": 0,
        "documents_processed": 0,
        "documents_indexed": 0,
        "index_time_in_millis": 0,
        "search_time_in_millis": 0
      }
    }
  }
}
```

## Preview a transform job's results

Returns a preview of what a transformed index would look like.

**Sample Request**

```json
POST _plugins/_transform/_preview

{
  "transform": {
  "enabled": false,
  "schedule": {
    "interval": {
    "period": 1,
    "unit": "Minutes",
    "start_time": 1602100553
    }
  },
  "description": "test transform",
  "source_index": "sample_index",
  "target_index": "sample_target",
  "data_selection_query": {
    "match_all": {}
  },
  "page_size": 10,
  "groups": [
    {
    "terms": {
      "source_field": "customer_gender",
      "target_field": "gender"
    }
    },
    {
    "terms": {
      "source_field": "day_of_week",
      "target_field": "day"
    }
    }
  ],
  "aggregations": {
    "quantity": {
    "sum": {
      "field": "total_quantity"
    }
    }
  }
  }
}
```

**Sample Response**

```json
{
  "documents" : [
  {
    "quantity" : 862.0,
    "gender" : "FEMALE",
    "day" : "Friday"
  },
  {
    "quantity" : 682.0,
    "gender" : "FEMALE",
    "day" : "Monday"
  },
  {
    "quantity" : 772.0,
    "gender" : "FEMALE",
    "day" : "Saturday"
  },
  {
    "quantity" : 669.0,
    "gender" : "FEMALE",
    "day" : "Sunday"
  },
  {
    "quantity" : 887.0,
    "gender" : "FEMALE",
    "day" : "Thursday"
  }
  ]
}
```

## Delete a transform job

Deletes a transform job. This operation does not delete the source or target indices.

**Sample Request**

```json
DELETE _plugins/_transform/<transform_id>
```

**Sample Response**

```json
{
  "took": 205,
  "errors": false,
  "items": [
    {
      "delete": {
        "_index": ".opensearch-ism-config",
        "_type": "_doc",
        "_id": "sample",
        "_version": 4,
        "result": "deleted",
        "forced_refresh": true,
        "_shards": {
          "total": 2,
          "successful": 1,
          "failed": 0
        },
        "_seq_no": 6,
        "_primary_term": 1,
        "status": 200
      }
    }
  ]
}
```