Add verbose_pipeline documentation section in using-search-pipeline

_search-plugins/search-pipelines/debugging-search-pipeline.md

@@ -0,0 +1,230 @@
+---
+layout: default
+title: Debugging a search pipeline
+nav_order: 25
+has_children: false
+parent: Search pipelines
+grand_parent: Search
+---
+
+
+# Debugging a search pipeline
+
+The `verbose_pipeline` parameter provides detailed insights into data flow and transformations for the search request, search response, and search phase processors in the search pipeline. It helps with troubleshooting and optimizing the pipeline and ensures transparency in handling search requests and responses. 
+
+## Enabling debugging
+
+To enable pipeline debugging, specify `verbose_pipeline=true` as a query parameter in your search request. This functionality is available for all three methods of using a search pipeline:
+
+- [Default search pipeline](#default-search-pipeline)
+- [Specific search pipeline](#specific-search-pipeline)
+- [Temporary search pipeline](#temporary-search-pipeline)
+
+### Default search pipeline
+
+To use `verbose_pipeline` with a default search pipeline, set the pipeline as the default in the index settings and include `verbose_pipeline=true` in the query:
+
+```json
+PUT /my_index/_settings
+{
+  "index.search.default_pipeline": "my_pipeline"
+}
+```
+{% include copy-curl.html %}
+
+```json
+GET /my_index/_search?verbose_pipeline=true
+```
+{% include copy-curl.html %}
+
+For more information about default search pipelines, see [Setting a default pipeline for all requests in an index]({{site.url}}{{site.baseurl}}/search-plugins/search-pipelines/using-search-pipeline/#default-search-pipeline).
+
+### Specific search pipeline 
+
+To use `verbose_pipeline` with a specific search pipeline, specify the pipeline ID and include `verbose_pipeline=true` in the query:
+
+```json
+GET /my_index/_search?search_pipeline=my_pipeline&verbose_pipeline=true
+```
+{% include copy-curl.html %}
+
+For more information, about using specific search pipelines see [Specifying an existing pipeline for a request]({{site.url}}{{site.baseurl}}/search-plugins/search-pipelines/using-search-pipeline/#specifying-an-existing-search-pipeline-for-a-request).
+
+### Temporary search pipeline
+
+To use `verbose_pipeline` with a temporary search pipeline, define the pipeline directly in the request body and include `verbose_pipeline=true` in the query:
+
+```json
+POST /my_index/_search?verbose_pipeline=true
+{
+  "query": {
+    "match": { "text_field": "some search text" }
+  },
+  "search_pipeline": {
+    "request_processors": [
+      {
+        "filter_query": {
+          "query": { "term": { "visibility": "public" } }
+        }
+      }
+    ],
+    "response_processors": [
+      {
+        "collapse": {
+          "field": "category"
+        }
+      }
+    ]
+  }
+}
+```
+{% include copy-curl.html %}
+
+For more information about using a temporary search pipeline, see [Using a temporary pipeline for a request]({{site.url}}{{site.baseurl}}/search-plugins/search-pipelines/using-search-pipeline/#using-a-temporary-search-pipeline-for-a-request).
+
+## Example response
+
+When the `verbose_pipeline` parameter is enabled, the response contains an additional `processor_results` field that details the transformations applied by each processor in the pipeline:
+
+<details open markdown="block">
+  <summary>
+    Response
+  </summary>
+  {: .text-delta}
+
+```json
+{
+    "took": 27,
+    "timed_out": false,
+    "_shards": {
+        "total": 1,
+        "successful": 1,
+        "skipped": 0,
+        "failed": 0
+    },
+    "hits": {
+        "total": {
+            "value": 1,
+            "relation": "eq"
+        },
+        "max_score": 0.18232156,
+        "hits": [
+            {
+                "_index": "my_index",
+                "_id": "1",
+                "_score": 0.18232156,
+                "_source": {
+                    "notification": "This is a public message",
+                    "visibility": "public"
+                }
+            }
+        ]
+    },
+    "processor_results": [
+        {
+            "processor_name": "filter_query",
+            "tag": "tag1",
+            "duration_millis": 288541,
+            "status": "success",
+            "input_data": {
+                "verbose_pipeline": true,
+                "query": {
+                    "bool": {
+                        "adjust_pure_negative": true,
+                        "must": [
+                            {
+                                "match": {
+                                    "message": {
+                                        "auto_generate_synonyms_phrase_query": true,
+                                        "query": "this",
+                                        "zero_terms_query": "NONE",
+                                        "fuzzy_transpositions": true,
+                                        "boost": 1.0,
+                                        "prefix_length": 0,
+                                        "operator": "OR",
+                                        "lenient": false,
+                                        "max_expansions": 50
+                                    }
+                                }
+                            }
+                        ],
+                        "boost": 1.0
+                    }
+                }
+            },
+            "output_data": {
+                "verbose_pipeline": true,
+                "query": {
+                    "bool": {
+                        "filter": [
+                            {
+                                "term": {
+                                    "visibility": {
+                                        "boost": 1.0,
+                                        "value": "public"
+                                    }
+                                }
+                            }
+                        ],
+                        "adjust_pure_negative": true,
+                        "must": [
+                            {
+                                "bool": {
+                                    "adjust_pure_negative": true,
+                                    "must": [
+                                        {
+                                            "match": {
+                                                "message": {
+                                                    "auto_generate_synonyms_phrase_query": true,
+                                                    "query": "this",
+                                                    "zero_terms_query": "NONE",
+                                                    "fuzzy_transpositions": true,
+                                                    "boost": 1.0,
+                                                    "prefix_length": 0,
+                                                    "operator": "OR",
+                                                    "lenient": false,
+                                                    "max_expansions": 50
+                                                }
+                                            }
+                                        }
+                                    ],
+                                    "boost": 1.0
+                                }
+                            }
+                        ],
+                        "boost": 1.0
+                    }
+                }
+            }
+        },
+        {
+            "processor_name": "rename_field",
+            "duration_millis": 250042,
+            "status": "success",
+            "input_data": [
+                {
+                    "_index": "my_index",
+                    "_id": "1",
+                    "_score": 0.18232156,
+                    "_source": {
+                        "message": "This is a public message",
+                        "visibility": "public"
+                    }
+                }
+            ],
+            "output_data": [
+                {
+                    "_index": "my_index",
+                    "_id": "1",
+                    "_score": 0.18232156,
+                    "_source": {
+                        "notification": "This is a public message",
+                        "visibility": "public"
+                    }
+                }
+            ]
+        }
+    ]
+}
+```
+</details>