--- title: Date index name processor description: The purpose of this processor is to point documents to the right time based index based on a date or timestamp field in a document by using the date math... url: https://www.elastic.co/elastic/docs-builder/docs/3028/reference/enrich-processor/date-index-name-processor products: - Elasticsearch --- # Date index name processor The purpose of this processor is to point documents to the right time based index based on a date or timestamp field in a document by using the [date math index name support](/elastic/docs-builder/docs/3028/reference/elasticsearch/rest-apis/api-conventions#api-date-math-index-names). The processor sets the `_index` metadata field with a date math index name expression based on the provided index name prefix, a date or timestamp field in the documents being processed and the provided date rounding. First, this processor fetches the date or timestamp from a field in the document being processed. Optionally, date formatting can be configured on how the field’s value should be parsed into a date. Then this date, the provided index name prefix and the provided date rounding get formatted into a date math index name expression. Also here optionally date formatting can be specified on how the date should be formatted into a date math index name expression. An example pipeline that points documents to a monthly index that starts with a `my-index-` prefix based on a date in the `date1` field: ```json { "description": "monthly date-time index naming", "processors" : [ { "date_index_name" : { "field" : "date1", "index_name_prefix" : "my-index-", "date_rounding" : "M" } } ] } ``` Using that pipeline for an index request: ```json { "date1" : "2016-04-25T12:02:01.789Z" } ``` ```json { "_index" : "my-index-2016-04-01", "_id" : "1", "_version" : 1, "result" : "created", "_shards" : { "total" : 2, "successful" : 1, "failed" : 0 }, "_seq_no" : 55, "_primary_term" : 1 } ``` The above request will not index this document into the `my-index` index, but into the `my-index-2016-04-01` index because it was rounded by month. This is because the date-index-name-processor overrides the `_index` property of the document. To see the date-math value of the index supplied in the actual index request which resulted in the above document being indexed into `my-index-2016-04-01` we can inspect the effects of the processor using a simulate request. ```json { "pipeline" : { "description": "monthly date-time index naming", "processors" : [ { "date_index_name" : { "field" : "date1", "index_name_prefix" : "my-index-", "date_rounding" : "M" } } ] }, "docs": [ { "_source": { "date1": "2016-04-25T12:02:01.789Z" } } ] } ``` and the result: ```json { "docs" : [ { "doc" : { "_id" : "_id", "_index" : "", "_version" : "-3", "_source" : { "date1" : "2016-04-25T12:02:01.789Z" }, "_ingest" : { "timestamp" : "2016-11-08T19:43:03.850+0000" } } } ] } ``` The above example shows that `_index` was set to ``. Elasticsearch understands this to mean `2016-04-01` as is explained in the [date math index name documentation](/elastic/docs-builder/docs/3028/reference/elasticsearch/rest-apis/api-conventions#api-date-math-index-names) | Name | Required | Default | Description | |---------------------|----------|-----------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | `field` | yes | - | The field to get the date or timestamp from. | | `index_name_prefix` | no | - | A prefix of the index name to be prepended before the printed date. Supports [template snippets](https://docs-v3-preview.elastic.dev/elastic/docs-builder/docs/3028/manage-data/ingest/transform-enrich/ingest-pipelines#template-snippets). | | `date_rounding` | yes | - | How to round the date when formatting the date into the index name. Valid values are: `y` (year), `M` (month), `w` (week), `d` (day), `h` (hour), `m` (minute) and `s` (second). Supports [template snippets](https://docs-v3-preview.elastic.dev/elastic/docs-builder/docs/3028/manage-data/ingest/transform-enrich/ingest-pipelines#template-snippets). | | `date_formats` | no | yyyy-MM-dd'T'HH:mm:ss.SSSXX | An array of the expected date formats for parsing dates / timestamps in the document being preprocessed. Can be a java time pattern or one of the following formats: ISO8601, UNIX, UNIX_MS, or TAI64N. | | `timezone` | no | UTC | The timezone to use when parsing the date and when date math index supports resolves expressions into concrete index names. | | `locale` | no | ENGLISH | The locale to use when parsing the date from the document being preprocessed, relevant when parsing month names or week days. | | `index_name_format` | no | yyyy-MM-dd | The format to be used when printing the parsed date into the index name. A valid java time pattern is expected here. Supports [template snippets](https://docs-v3-preview.elastic.dev/elastic/docs-builder/docs/3028/manage-data/ingest/transform-enrich/ingest-pipelines#template-snippets). | | `description` | no | - | Description of the processor. Useful for describing the purpose of the processor or its configuration. | | `if` | no | - | Conditionally execute the processor. See [Conditionally run a processor](https://docs-v3-preview.elastic.dev/elastic/docs-builder/docs/3028/manage-data/ingest/transform-enrich/ingest-pipelines#conditionally-run-processor). | | `ignore_failure` | no | `false` | Ignore failures for the processor. See [Handling pipeline failures](https://docs-v3-preview.elastic.dev/elastic/docs-builder/docs/3028/manage-data/ingest/transform-enrich/ingest-pipelines#handling-pipeline-failures). | | `on_failure` | no | - | Handle failures for the processor. See [Handling pipeline failures](https://docs-v3-preview.elastic.dev/elastic/docs-builder/docs/3028/manage-data/ingest/transform-enrich/ingest-pipelines#handling-pipeline-failures). | | `tag` | no | - | Identifier for the processor. Useful for debugging and metrics. |