This modules enables a dropwizard application to send metrics to an elasticsearch instance.

No, it doesn't. As outlined here, it needs you to write some code in your application. This module adds the ability to perform that task through your dropwizard application yaml configuration. In fact, under the hood it actually makes use of Metrics Elasticsearch Reporter to perform the work.

• add this jar as a dependency to the dropwizard app:

<dependencies>
    ../..
    <dependency>
        <groupId>org.dhatim.io.dropwizard</groupId>
        <artifactId>dropwizard-metrics-elasticsearch</artifactId>
        <version>1.0.8</version>
    </dependency>
    ../..
</dependencies>

• enable the metrics reporter through the configuration:

metrics:
  reporters:
    - type: elasticsearch

and you're good to go.

The configuration is somewhat limited right now:

• servers: you can configure a set of elasticsearch nodes with the servers key, which hold a collection of host and port keys.
• prefix: useful to identify single hosts.
• index: elasticsearch index name.
• indexDateFormat: elasticsearch index date format.
• additionalFields: optional map of additional field values.

metrics:
  reporters:
    - type: elasticsearch
      servers:
        - host: localhost
          port: 9200
      prefix:
      index: metrics
      indexDateFormat: yyyy.MM.dd
      additionalFields:

It should basically follow the Metrics Elasticsearch Reporter defaults.