Painless is a simple, secure scripting language that is available in Elasticsearch by default. It was designed by the Elasticsearch team to be used specifically with Elasticsearch and can safely be used with inline and stored scripting. Its syntax is similar to Groovy.
Painless scripting
Getting ready
You will need an up-and-running Elasticsearch installation – similar to the one that we described in the Downloading and installing Elasticsearch recipe in Chapter 1, Getting Started.
In order to execute the commands, any HTTP client can be used, such as Curl (https://curl.haxx.se/) or Postman (https://www.getpostman.com/). You can use the Kibana console as it provides code completion and better...