Add Split Response Processor to 2.17 Search Pipeline docs

_search-plugins/search-pipelines/search-processors.md

@@ -45,6 +45,7 @@ Processor | Description | Earliest available version
 [`rerank`]({{site.url}}{{site.baseurl}}/search-plugins/search-pipelines/rerank-processor/)| Reranks search results using a cross-encoder model. | 2.12
 [`retrieval_augmented_generation`]({{site.url}}{{site.baseurl}}/search-plugins/search-pipelines/rag-processor/) | Used for retrieval-augmented generation (RAG) in [conversational search]({{site.url}}{{site.baseurl}}/search-plugins/conversational-search/). | 2.10 (generally available in 2.12)
 [`sort`]({{site.url}}{{site.baseurl}}/search-plugins/search-pipelines/sort-processor/)| Sorts an array of items in either ascending or descending order. | 2.16
+[`split`]({{site.url}}{{site.baseurl}}/search-plugins/search-pipelines/split-processor/)| Splits a string field into an array of substrings based on a specified delimiter. | 2.17
 [`truncate_hits`]({{site.url}}{{site.baseurl}}/search-plugins/search-pipelines/truncate-hits-processor/)| Discards search hits after a specified target count is reached. Can undo the effect of the `oversample` request processor.  | 2.12
 
 

_search-plugins/search-pipelines/split-processor.md

@@ -0,0 +1,236 @@
+---
+layout: default
+title: Split
+nav_order: 140
+has_children: false
+parent: Search processors
+grand_parent: Search pipelines
+---
+
+# Split processor
+Introduced 2.17
+{: .label .label-purple }
+
+The `split` processor splits a string field into an array of substrings based on a specified delimiter.
+
+## Request fields
+
+The following table lists all available request fields.
+
+Field | Data type | Description
+:--- | :--- | :---
+`field` | String | The field containing the string to be split. Required.
+`separator` | String | The delimiter used to split the string. Specify either a single separator character or a regular expression pattern. Required.
+`preserve_trailing` | Boolean | If set to `true`, preserves empty trailing fields (for example, `''`) in the resulting array. If set to `false`, then empty trailing fields are removed from the resulting array. Default is `false`. 
+`target_field` | String | The field in which the array of substrings is stored. If not specified, then the field is updated in place. 
+`tag` | String | The processor's identifier. 
+`description` | String | A description of the processor. 
+`ignore_failure` | Boolean | If `true`, then OpenSearch [ignores any failure]({{site.url}}{{site.baseurl}}/search-plugins/search-pipelines/creating-search-pipeline/#ignoring-processor-failures) of this processor and continues to run the remaining processors in the search pipeline. Optional. Default is `false`.
+
+## Example 
+
+The following example demonstrates using a search pipeline with a `split` processor.
+
+### Setup
+
+Create an index named `my_index` and index a document containing the field `message`:
+
+```json
+POST /my_index/_doc/1
+{
+  "message": "ingest, search, visualize, and analyze data",
+  "visibility": "public"
+}
+```
+{% include copy-curl.html %}
+
+### Creating a search pipeline 
+
+The following request creates a search pipeline with a `split` response processor that splits the `message` field and stores the results in the `split_message` field:
+
+```json
+PUT /_search/pipeline/my_pipeline
+{
+  "response_processors": [
+    {
+      "split": {
+        "field": "message",
+        "separator": ", ",
+        "target_field": "split_message"
+      }
+    }
+  ]
+}
+```
+{% include copy-curl.html %}
+
+### Using a search pipeline
+
+Search for documents in `my_index` without a search pipeline:
+
+```json
+GET /my_index/_search
+```
+{% include copy-curl.html %}
+
+The response contains the field `message`:
+
+<details open markdown="block">
+  <summary>
+    Response
+  </summary>
+  {: .text-delta}
+```json
+{
+  "took": 3,
+  "timed_out": false,
+  "_shards": {
+    "total": 1,
+    "successful": 1,
+    "skipped": 0,
+    "failed": 0
+  },
+  "hits": {
+    "total": {
+      "value": 1,
+      "relation": "eq"
+    },
+    "max_score": 1,
+    "hits": [
+      {
+        "_index": "my_index",
+        "_id": "1",
+        "_score": 1,
+        "_source": {
+          "message": "ingest, search, visualize, and analyze data",
+          "visibility": "public"
+        }
+      }
+    ]
+  }
+}
+```
+</details>
+
+To search with a pipeline, specify the pipeline name in the `search_pipeline` query parameter:
+
+```json
+GET /my_index/_search?search_pipeline=my_pipeline
+```
+{% include copy-curl.html %}
+
+The `message` field is split and the results are stored in the `split_message` field:
+
+<details open markdown="block">
+  <summary>
+    Response
+  </summary>
+  {: .text-delta}
+
+```json
+{
+  "took": 6,
+  "timed_out": false,
+  "_shards": {
+    "total": 1,
+    "successful": 1,
+    "skipped": 0,
+    "failed": 0
+  },
+  "hits": {
+    "total": {
+      "value": 1,
+      "relation": "eq"
+    },
+    "max_score": 1,
+    "hits": [
+      {
+        "_index": "my_index",
+        "_id": "1",
+        "_score": 1,
+        "_source": {
+          "visibility": "public",
+          "message": "ingest, search, visualize, and analyze data",
+          "split_message": [
+            "ingest",
+            "search",
+            "visualize",
+            "and analyze data"
+          ]
+        }
+      }
+    ]
+  }
+}
+```
+</details>
+
+You can also use the `fields` option to search for specific fields in a document:
+
+```json
+POST /my_index/_search?pretty&search_pipeline=my_pipeline
+{
+    "fields": ["visibility", "message"]
+}
+``` 
+{% include copy-curl.html %}
+
+In the response, the `message` field is split and the results are stored in the `split_message` field:
+
+<details open markdown="block">
+  <summary>
+    Response
+  </summary>
+  {: .text-delta}
+
+```json
+{
+  "took": 7,
+  "timed_out": false,
+  "_shards": {
+    "total": 1,
+    "successful": 1,
+    "skipped": 0,
+    "failed": 0
+  },
+  "hits": {
+    "total": {
+      "value": 1,
+      "relation": "eq"
+    },
+    "max_score": 1,
+    "hits": [
+      {
+        "_index": "my_index",
+        "_id": "1",
+        "_score": 1,
+        "_source": {
+          "visibility": "public",
+          "message": "ingest, search, visualize, and analyze data",
+          "split_message": [
+            "ingest",
+            "search",
+            "visualize",
+            "and analyze data"
+          ]
+        },
+        "fields": {
+          "visibility": [
+            "public"
+          ],
+          "message": [
+            "ingest, search, visualize, and analyze data"
+          ],
+          "split_message": [
+            "ingest",
+            "search",
+            "visualize",
+            "and analyze data"
+          ]
+        }
+      }
+    ]
+  }
+}
+```
+</details>