Elasticsearch OpenSearch Template

By Opster Team

Updated: Aug 29, 2023

| 2 min read

Before you dig into the details of this technical guide, have you tried asking OpsGPT?

You'll receive concise answers that will help streamline your Elasticsearch/OpenSearch operations.


Try OpsGPT now for step-by-step guidance and tailored insights into your Elasticsearch/ OpenSearch operation.

Before you dig into the details of this guide, have you tried asking OpsGPT? You’ll receive concise answers that will help streamline your OpenSearch/Elasticsearch operation.

Try OpsGPT now for step-by-step guidance and tailored insights into your search operation.

To easily resolve issues in your deployment and locate their root cause, try AutoOps for OpenSearch. It diagnoses problems by analyzing hundreds of metrics collected by a lightweight agent and offers guidance for resolving them. Try AutoOps for free.

Quick links

Overview

A template in OpenSearch falls into one of the two following categories and is indexed inside OpenSearch using its dedicated endpoint: 

  1. Index templates, which are a way to define a set of rules including index settings, mappings and an index pattern. The template is applied automatically whenever a new index is created with the matching pattern. Templates are also used to dynamically apply custom mapping for the fields which are not predefined inside existing mapping.
  2. Search templates, which help in defining templates for search queries using mustache scripting language. These templates act as a placeholder for variables defined inside the search queries.

Examples

Create a dynamic index template

PUT /_template/template_1?pretty
{
  "index_patterns": [
    "logs*",
    "api*"
  ],
  "settings": {
    "number_of_shards": 2
  },
  "mappings": {
    "dynamic_templates": [
      {
        "strings": {
          "match_mapping_type": "string",
          "mapping": {
            "type": "keyword"
          }
        }
      }
    ],
    "properties": {
      "host_name": {
        "type": "keyword"
      },
      "created_at": {
        "type": "date"
      }
    }
  }
}

Create a search template

POST /_scripts/search_template_1?pretty
{
    "script": {
        "lang": "mustache",
        "source": {
            "query": {
                "match": {
                    "description": "{{query_string}}"
                }
            }
        }
    }
}

Executing a search query using search template

GET /_search/template?pretty
{
    "id": "search_template_1", 
    "params": {
        "query_string": "hello world"
    }
}

The search request will be executed by default on all the indices available in the cluster and can be limited to particular indices using an index parameter.

Notes

  • A dynamic index template is always useful when you do not know the field names in advance and want to control their mapping as per the business use case.

How helpful was this guide?

We are sorry that this post was not useful for you!

Let us improve this post!

Tell us how we can improve this post?


Get expert answers on Elasticsearch/OpenSearch