
Elasticsearch 5.x Cookbook
By :

Elasticsearch provides native scripting (a Java code compiled in JAR) and Painless, but a lot of interesting languages are available, such as JavaScript and Python.
As previously stated, the official language is now Painless, and this is provided by default in Elasticsearch for better sandboxing and performance.
Other scripting languages can be installed as plugins, thus they are now deprecated. We will present them in this recipe as they have a large user base.
You need an up-and-running Elasticsearch installation as we described in the Downloading and installing Elasticsearch recipe in Chapter 2, Downloading and Setup.
To install JavaScript language support for Elasticsearch, we will perform the following steps:
From the command line, simply call the following command:
bin/elasticsearch-plugin install lang-javascript
It will print the following output:
-> Downloading lang-javascript from elastic ...
Change the font size
Change margin width
Change background colour