elasticsearch/docs/reference/scripting-languages/painless/painless.md

mapped_pages	products
https://www.elastic.co/guide/en/elasticsearch/painless/current/index.html https://www.elastic.co/guide/en/elasticsearch/painless/current/painless-guide.html	id painless

Painless [painless-guide]

Painless is a simple, secure scripting language designed specifically for use with Elasticsearch. It is the default scripting language for Elasticsearch and can safely be used for inline and stored scripts. For a jump start into Painless, see A Brief Painless Walkthrough. For a detailed description of the Painless syntax and language features, see the Painless Language Specification.

You can use Painless anywhere scripts are used in Elasticsearch. Painless provides:

• Fast performance: Painless scripts run several times faster than the alternatives.
• Safety: Fine-grained allowlist with method call/field granularity.
• Optional typing: Variables and parameters can use explicit types or the dynamic def type.
• Syntax: Extends a subset of Java’s syntax to provide additional scripting language features.
• Optimizations: Designed specifically for Elasticsearch scripting.