Create or update index template API

A PutIndexTemplateRequest specifies the name of a template and patterns which controls whether the template should be applied to the new index.

PutIndexTemplateRequest request = new PutIndexTemplateRequest("my-template"); 
request.patterns(asList("pattern-1", "log-*")); 

The settings of the template will be applied to the new index whose name matches the template’s patterns.

request.settings(Settings.builder() 
    .put("index.number_of_shards", 3)
    .put("index.number_of_replicas", 1)
);

The mapping of the template will be applied to the new index whose name matches the template’s patterns.

request.mapping(
    "{\n" +
        "  \"properties\": {\n" +
        "    \"message\": {\n" +
        "      \"type\": \"text\"\n" +
        "    }\n" +
        "  }\n" +
        "}",
    XContentType.JSON);

The mapping source can be provided in different ways in addition to the String example shown above:

Map<String, Object> jsonMap = new HashMap<>();
{
    Map<String, Object> properties = new HashMap<>();
    {
        Map<String, Object> message = new HashMap<>();
        message.put("type", "text");
        properties.put("message", message);
    }
    jsonMap.put("properties", properties);
}
request.mapping(jsonMap); 

XContentBuilder builder = XContentFactory.jsonBuilder();
builder.startObject();
{
    builder.startObject("properties");
    {
        builder.startObject("message");
        {
            builder.field("type", "text");
        }
        builder.endObject();
    }
    builder.endObject();
}
builder.endObject();
request.mapping(builder); 

The aliases of the template will define aliasing to the index whose name matches the template’s patterns. A placeholder {index} can be used in an alias of a template.

request.alias(new Alias("twitter_alias").filter(QueryBuilders.termQuery("user", "kimchy")));  
request.alias(new Alias("{index}_alias").searchRouting("xyz"));  

In case multiple templates match an index, the orders of matching templates determine the sequence that settings, mappings, and alias of each matching template is applied. Templates with lower orders are applied first, and higher orders override them.

request.order(20);  

A template can optionally specify a version number which can be used to simplify template management by external systems.

request.version(4);  

The whole source including all of its sections (mappings, settings and aliases) can also be provided:

request.source("{\n" +
    "  \"index_patterns\": [\n" +
    "    \"log-*\",\n" +
    "    \"pattern-1\"\n" +
    "  ],\n" +
    "  \"order\": 1,\n" +
    "  \"settings\": {\n" +
    "    \"number_of_shards\": 1\n" +
    "  },\n" +
    "  \"mappings\": {\n" +
    "    \"properties\": {\n" +
    "      \"message\": {\n" +
    "        \"type\": \"text\"\n" +
    "      }\n" +
    "    }\n" +
    "  },\n" +
    "  \"aliases\": {\n" +
    "    \"alias-1\": {},\n" +
    "    \"{index}-alias\": {}\n" +
    "  }\n" +
    "}", XContentType.JSON); 

The following arguments can optionally be provided:

request.create(true);  

request.masterNodeTimeout(TimeValue.timeValueMinutes(1)); 
request.masterNodeTimeout("1m"); 

When executing a PutIndexTemplateRequest in the following manner, the client waits for the PutIndexTemplateResponse to be returned before continuing with code execution:

AcknowledgedResponse putTemplateResponse = client.indices().putTemplate(request, LEGACY_TEMPLATE_OPTIONS);

Synchronous calls may throw an IOException in case of either failing to parse the REST response in the high-level REST client, the request times out or similar cases where there is no response coming back from the server.

In cases where the server returns a 4xx or 5xx error code, the high-level client tries to parse the response body error details instead and then throws a generic ElasticsearchException and adds the original ResponseException as a suppressed exception to it.

Executing a PutIndexTemplateRequest can also be done in an asynchronous fashion so that the client can return directly. Users need to specify how the response or potential failures will be handled by passing the request and a listener to the asynchronous put-template method:

client.indices().putTemplateAsync(request, LEGACY_TEMPLATE_OPTIONS, listener); 

The asynchronous method does not block and returns immediately. Once it is completed the ActionListener is called back using the onResponse method if the execution successfully completed or using the onFailure method if it failed. Failure scenarios and expected exceptions are the same as in the synchronous execution case.

A typical listener for put-template looks like:

ActionListener<AcknowledgedResponse> listener =
    new ActionListener<AcknowledgedResponse>() {
        @Override
        public void onResponse(AcknowledgedResponse putTemplateResponse) {
            
        }

        @Override
        public void onFailure(Exception e) {
            
        }
    };

The returned PutIndexTemplateResponse allows to retrieve information about the executed operation as follows:

boolean acknowledged = putTemplateResponse.isAcknowledged();