[Backport 2.11] [DOC] Add kv processor content gap doc

_ingest-pipelines/processors/kv.md

@@ -0,0 +1,147 @@
+---
+layout: default
+title: KV
+parent: Ingest processors
+nav_order: 200
+redirect_from:
+   - /api-reference/ingest-apis/processors/lowercase/
+---
+
+# KV processor
+
+The `kv` processor automatically extracts specific event fields or messages that are in a `key=value` format. This structured format organizes your data by grouping it together based on keys and values. It's helpful for analyzing, visualizing, and using data, such as user behavior analytics, performance optimizations, or security investigations. 
+
+## Example
+
+The following is the syntax for the `kv` processor: 
+
+```json
+{
+  "kv": {
+    "field": "message",
+    "field_split": " ",
+    "value_split": " "
+  }
+}
+```
+{% include copy-curl.html %}
+
+## Configuration parameters
+
+The following table lists the required and optional parameters for the `kv` processor.
+
+| Parameter  | Required/Optional  | Description  |
+`field`  | Required  | The name of the field containing the data to be parsed. Supports [template snippets]({{site.url}}{{site.baseurl}}/ingest-pipelines/create-ingest/#template-snippets). |
+`field_split` | Required | The regex pattern for key-value pair splitting. |
+`value_split` | Required | The regex pattern for splitting the key from the value within a key-value pair, for example, equal sign `=` or colon `:`.
+`exclude_keys` | Optional | The keys to exclude from the document. Default is `null`. |
+`include_keys` | Optional | The keys for filtering and inserting. Default is to include all keys. |
+`prefix` | Optional | The prefix to add to the extracted keys. Default is `null`. |
+`strip_brackets` | Optional | If set to `true`, strips brackets (`()`, `<>,` or `[]`) and quotes (`'` or `"`) from extracted values. Default is `false`.
+`trim_key` | Optional | The string of characters to trim from the extracted keys. | 
+`trim value` | Optional | The string of characters to trim from the extracted values. |
+`description`  | Optional  | A brief description of the processor.  |
+`if` | Optional | A condition for running the processor. |
+`ignore_failure` | Optional | If set to `true`, failures are ignored. Default is `false`. |
+`on_failure` | Optional | A list of processors to run if the processor fails. |
+`ignore_missing`  | Optional  | Specifies whether the processor should ignore documents that do not contain the specified field. Default is `false`.  |
+`tag` | Optional | An identifier tag for the processor. Useful for debugging in order to distinguish between processors of the same type. |
+`target_field`  | Optional  | The name of the field in which to insert the extracted keys. Default is `null`. Supports [template snippets]({{site.url}}{{site.baseurl}}/ingest-pipelines/create-ingest/#template-snippets). |
+
+## Using the processor
+
+Follow these steps to use the processor in a pipeline.
+
+**Step 1: Create a pipeline**
+
+The following query creates a pipeline, named `kv-pipeline`, that uses the `kv` processor to extract the `message` field of a document:
+
+```json
+PUT _ingest/pipeline/kv-pipeline
+{
+  "description" : "Pipeline that extracts user profile data",
+  "processors" : [
+    {
+      "kv" : {
+        "field" : "message",
+        "field_split": " ",
+        "value_split": "="
+      }
+    }
+  ]
+}
+```
+{% include copy-curl.html %}
+
+**Step 2 (Optional): Test the pipeline**
+
+It is recommended that you test your pipeline before you ingest documents.
+{: .tip}
+
+To test the pipeline, run the following query:
+
+```json
+POST _ingest/pipeline/kv-pipeline/_simulate
+
+```json
+{  
+  "docs": [  
+    {  
+      "_index": "testindex1",  
+      "_id": "1",  
+      "_source":{  
+         "message": "goodbye=everybody hello=world"  
+      }  
+    }  
+  ]  
+}
+```
+{% include copy-curl.html %}
+
+**Response**
+
+The following example response confirms that the pipeline is working as expected:
+
+```json
+{  
+  "docs": [  
+    {  
+      "doc": {  
+        "_index": "testindex1",  
+        "_id": "1",  
+        "_source": {  
+          "hello": "world",  
+          "message": "goodbye=everybody hello=world",  
+          "goodbye": "everybody"  
+        },  
+        "_ingest": {  
+          "timestamp": "2023-12-06T09:59:21.823292Z"  
+        }  
+      }  
+    }  
+  ]  
+}
+```
+
+**Step 3: Ingest a document**
+
+The following query ingests a document into an index named `testindex1`:
+
+```json
+PUT testindex1/_doc/1?pipeline=kv-pipeline
+
+```json
+{  
+  "message": "goodbye=everybody hello=world"  
+}  
+```
+{% include copy-curl.html %}
+
+**Step 4 (Optional): Retrieve the document**
+
+To retrieve the document, run the following query:
+
+```json
+GET testindex1/_doc/1
+```
+{% include copy-curl.html %}

_ingest-pipelines/processors/lowercase.md

@@ -29,15 +29,15 @@ The following is the syntax for the `lowercase` processor:
 
 The following table lists the required and optional parameters for the `lowercase` processor.
 
-| Name  | Required  | Description  |
+| Parameter  | Required  | Description  |
 |---|---|---|
-`field`  | Required  | The name of the field that contains the data to be converted. Supports template snippets. |
+`field`  | Required  | The name of the field containing the data to be converted. Supports [template snippets]({{site.url}}{{site.baseurl}}/ingest-pipelines/create-ingest/#template-snippets). |
 `description`  | Optional  | A brief description of the processor.  |
 `if` | Optional | A condition for running this processor. |
 `ignore_failure` | Optional | If set to `true`, failures are ignored. Default is `false`. |
 `on_failure` | Optional | A list of processors to run if the processor fails. |
 `ignore_missing`  | Optional  | Specifies whether the processor should ignore documents that do not have the specified field. Default is `false`.  |
-`tag` | Optional | An identifier tag for the processor. Useful for debugging to distinguish between processors of the same type. |
+`tag` | Optional | An identifier tag for the processor. Useful for debugging in order to distinguish between processors of the same type. |
 `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. |
 
 ## Using the processor