Book Image

ElasticSearch Cookbook

By : Alberto Paro
Book Image

ElasticSearch Cookbook

By: Alberto Paro

Overview of this book

ElasticSearch is one of the most promising NoSQL technologies available and is built to provide a scalable search solution with built-in support for near real-time search and multi-tenancy. This practical guide is a complete reference for using ElasticSearch and covers 360 degrees of the ElasticSearch ecosystem. We will get started by showing you how to choose the correct transport layer, communicate with the server, and create custom internal actions for boosting tailored needs. Starting with the basics of the ElasticSearch architecture and how to efficiently index, search, and execute analytics on it, you will learn how to extend ElasticSearch by scripting and monitoring its behaviour. Step-by-step, this book will help you to improve your ability to manage data in indexing with more tailored mappings, along with searching and executing analytics with facets. The topics explored in the book also cover how to integrate ElasticSearch with Python and Java applications. This comprehensive guide will allow you to master storing, searching, and analyzing data with ElasticSearch.
Table of Contents (19 chapters)
ElasticSearch Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Mapping a GeoShape field


An extension to the concept of point is the shape. ElasticSearch provides a type that facilitates the management of arbitrary polygons—the GeoShape.

Getting ready

You need a working ElasticSearch cluster with Spatial4J (V0.3) and JTS (v1.12) in the classpath to use this type.

How to do it...

To map a geo_shape type a user must explicitly provide some parameters:

  • tree (defaults to geohash): It's the name of the PrefixTree implementation; geohash for GeohashPrefixTree and quadtree for QuadPrefixTree.

  • precision: It's used instead of tree_levels to provide a more human value to be used in the tree level. The precision number can be followed by the unit, that is, 10 m, 10 km, 10 miles, and so on.

  • tree_levels: It's the maximum number of layers to be used in the PrefixTree.

  • distance_error_pct (defaults to 0,025% and max 0,5%): It sets the maximum error allowed in PrefixTree.

The customer_location mapping that we have seen in the previous recipe using geo_shape, will be:

"customer_location...