132 lines
3.1 KiB
Markdown
132 lines
3.1 KiB
Markdown
---
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layout: default
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title: Lowercase
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parent: Ingest processors
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nav_order: 210
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redirect_from:
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- /api-reference/ingest-apis/processors/lowercase/
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---
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# Lowercase processor
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**Introduced 1.0**
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{: .label .label-purple }
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The `lowercase` processor converts all the text in a specific field to lowercase letters.
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## Example
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The following is the syntax for the `lowercase` processor:
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```json
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{
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"lowercase": {
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"field": "field_name"
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}
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}
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```
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{% include copy-curl.html %}
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#### Configuration parameters
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The following table lists the required and optional parameters for the `lowercase` processor.
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| Name | Required | Description |
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|---|---|---|
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`field` | Required | The name of the field that contains the data to be converted. Supports template snippets. |
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`description` | Optional | A brief description of the processor. |
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`if` | Optional | A condition for running this processor. |
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`ignore_failure` | Optional | If set to `true`, failures are ignored. Default is `false`. |
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`on_failure` | Optional | A list of processors to run if the processor fails. |
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`ignore_missing` | Optional | Specifies whether the processor should ignore documents that do not have the specified field. Default is `false`. |
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`tag` | Optional | An identifier tag for the processor. Useful for debugging to distinguish between processors of the same type. |
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`target_field` | Optional | The name of the field in which to store the parsed data. Default is `field`. By default, `field` is updated in place. |
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## Using the processor
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Follow these steps to use the processor in a pipeline.
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**Step 1: Create a pipeline.**
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The following query creates a pipeline, named `lowercase-title`, that uses the `lowercase` processor to lowercase the `title` field of a document:
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```json
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PUT _ingest/pipeline/lowercase-title
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{
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"description" : "Pipeline that lowercases the title field",
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"processors" : [
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{
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"lowercase" : {
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"field" : "title"
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}
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}
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]
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}
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```
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{% include copy-curl.html %}
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**Step 2 (Optional): Test the pipeline.**
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It is recommended that you test your pipeline before you ingest documents.
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{: .tip}
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To test the pipeline, run the following query:
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```json
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POST _ingest/pipeline/lowercase-title/_simulate
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{
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"docs": [
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{
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"_index": "testindex1",
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"_id": "1",
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"_source": {
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"title": "WAR AND PEACE"
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}
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}
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]
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}
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```
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{% include copy-curl.html %}
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#### Response
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The following example response confirms that the pipeline is working as expected:
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```json
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{
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"docs": [
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{
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"doc": {
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"_index": "testindex1",
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"_id": "1",
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"_source": {
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"title": "war and peace"
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},
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"_ingest": {
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"timestamp": "2023-08-22T17:39:39.872671834Z"
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}
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}
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}
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]
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}
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```
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**Step 3: Ingest a document.**
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The following query ingests a document into an index named `testindex1`:
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```json
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PUT testindex1/_doc/1?pipeline=lowercase-title
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{
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"title": "WAR AND PEACE"
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}
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```
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{% include copy-curl.html %}
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**Step 4 (Optional): Retrieve the document.**
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To retrieve the document, run the following query:
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```json
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GET testindex1/_doc/1
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```
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{% include copy-curl.html %}
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