simulate-index.asciidoc

Simulate index API

Simulate index

Returns the index configuration that would be applied to the specified index from an existing index template.

POST /_index_template/_simulate_index/my-index-000001

{api-request-title}

POST /_index_template/_simulate_index/<index>

{api-prereq-title}

• If the {es} {security-features} are enabled, you must have the manage_index_templates or manage cluster privilege to use this API.

{api-path-parms-title}

<index>

(Required, string) Name of the index to simulate.

{api-query-parms-title}

{es-ref-dir}/rest-api/common-parms.asciidoc

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overlapping

(array) Any templates that also matched the index but were superseded by a higher-priority template. Response includes an empty array if there are no overlapping templates.

Properties of overlapping

name

(string) Name of the superseded template.

index_patterns

(array) Index patterns that the superseded template applies to.

template

(object) The settings, mappings, and aliases that would be applied to the index.

Properties of template

aliases

(object) Aliases for the index. If no aliases apply, the response returns an empty aliases object.

<alias>

(object) The key is the alias name. The object body contains options for the alias.

Properties of <alias>

filter

(Query DSL object) Query used to limit documents the alias can access.

index_routing

(string) Value used to route indexing operations to a specific shard. This overwrites the routing value for indexing operations.

is_hidden

(Boolean) If true, the alias is hidden.

is_write_index

(Boolean) If true, the index is the write index for the alias.

routing

(string) Value used to route indexing and search operations to a specific shard.

search_routing

(string) Value used to route search operations to a specific shard. This overwrites the routing value for search operations.

{es-ref-dir}/rest-api/common-parms.asciidoc

+ Omitted from the response if no mappings would be applied.

{es-ref-dir}/rest-api/common-parms.asciidoc

+ Response includes an empty object if no settings would be applied.

{api-examples-title}

The following example shows the configuration that would be applied to my-index-000001 by an existing template.

PUT /_component_template/ct1                    (1)
{
  "template": {
    "settings": {
      "index.number_of_shards": 2
    }
  }
}

PUT /_component_template/ct2                    (2)
{
  "template": {
    "settings": {
      "index.number_of_replicas": 0
    },
    "mappings": {
      "properties": {
        "@timestamp": {
          "type": "date"
        }
      }
    }
  }
}

PUT /_index_template/final-template             (3)
{
  "index_patterns": ["my-index-*"],
  "composed_of": ["ct1", "ct2"],
  "priority": 5
}

POST /_index_template/_simulate_index/my-index-000001 (4)

1. Create a component template (ct1) that sets the number of shards to 2

2. Create a second component template (ct2) that sets the number of replicas to 0 and defines a mapping

3. Create an index template (final-template) that uses the component templates

4. Show the configuration that would be applied to my-index-000001

The response shows the index settings, mappings, and aliases applied by the final-template:

{
  "template" : {
    "settings" : {
      "index" : {
        "number_of_shards" : "2",
        "number_of_replicas" : "0",
        "routing" : {
          "allocation" : {
            "include" : {
              "_tier_preference" : "data_content"
            }
          }
        }
      }
    },
    "mappings" : {
      "properties" : {
        "@timestamp" : {
          "type" : "date"
        }
      }
    },
    "aliases" : { }
  },
  "overlapping" : [
    {
      "name" : "template_1",
      "index_patterns" : [
        "my-index-*"
      ]
    }
  ]
}