Painless is a performant, secure scripting language designed specifically for Elasticsearch. You can use Painless to safely write inline and stored scripts anywhere scripts are supported in Elasticsearch.
- Safety: Ensuring the security of your cluster is of utmost importance. To that end, Painless uses a fine-grained allowlist with a granularity down to the members of a class. Anything that is not part of the allowlist results in a compilation error. See the Painless API Reference for a complete list of available classes, methods, and fields per script context.
- Performance: Painless compiles directly into JVM bytecode to take advantage of all possible optimizations that the JVM provides. Also, Painless typically avoids features that require additional slower checks at runtime.
- Simplicity: Painless implements a syntax with a natural familiarity to anyone with some basic coding experience. Painless uses a subset of Java syntax with some additional improvements to enhance readability and remove boilerplate.
Ready to start scripting with Painless? Learn how to write your first script.
If you’re already familiar with Painless, see the Painless Language Specification for a detailed description of the Painless syntax and language features.