Book Image

Elasticsearch 5.x Cookbook - Third Edition

By : Alberto Paro
Book Image

Elasticsearch 5.x Cookbook - Third Edition

By: Alberto Paro

Overview of this book

Elasticsearch is a Lucene-based distributed search server that allows users to index and search unstructured content with petabytes of data. This book is your one-stop guide to master the complete Elasticsearch ecosystem. We’ll guide you through comprehensive recipes on what’s new in Elasticsearch 5.x, showing you how to create complex queries and analytics, and perform index mapping, aggregation, and scripting. Further on, you will explore the modules of Cluster and Node monitoring and see ways to back up and restore a snapshot of an index. You will understand how to install Kibana to monitor a cluster and also to extend Kibana for plugins. Finally, you will also see how you can integrate your Java, Scala, Python, and Big Data applications such as Apache Spark and Pig with Elasticsearch, and add enhanced functionalities with custom plugins. By the end of this book, you will have an in-depth knowledge of the implementation of the Elasticsearch architecture and will be able to manage data efficiently and effectively with Elasticsearch.
Table of Contents (25 chapters)
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Dedication
Preface

Creating a cluster action


In the previous recipe, we saw how to create a REST entry-point, but to execute the action at cluster level, we will need to create a cluster action.

An Elasticsearch action is generally executed and distributed in the cluster and in this recipe we will see how to implement this kind of action. The cluster action will be very bare; we send a string with a value to every shard and the shards echo a result string concatenating the string with the shard number.

Getting ready

You need an up-and-running Elasticsearch installation as we described in the Downloading and installing Elasticsearch recipe in Chapter 2, Downloading and Setup.

A Maven tool, or an IDE that support Java programming, such as Eclipse or IntelliJ IDEA. The code for this recipe is available in the chapter17/rest_plugin directory.

How to do it...

In this recipe we will see that a REST call is converted to an internal cluster action. To execute an internal cluster action, some classes are required:

  • A Request...