Kelp Query Language (KelpQL)

KelpQL is Kelp’s JSON-based query and transformation language.

It is used to select, filter, reshape, and compute over JSON data events flowing through wires.

KelpQL is inspired by JMESPath and Lodash, and is designed to:

• Work with arbitrary JSON structures
• Enable expressive, declarative transformations
• Reduce the need for custom code in dataflows

This section defines the KelpQL language specification and documents all supported functions and operators.

For learning and experimentation, refer to the KelpQL Tutorial and the KelpQL Playground. The Reference focuses on precise language semantics and function behavior.

📄️ Specification

KelpQL implementation based on JMESPath, but with its own unique features and modifications. This document describes the specifications for KelpQL and is based on the original JMESPath specification.

📄️ Cheat Sheet

KelpQL is a JSON query language that is based on JMESPath. This cheat sheet provides a quick reference to all the important concepts and syntax of KelpQL. For a more comprehensive overview of the KelpQL specification, please refer to the KelpQL specification.

📄️ Array functions

Perform various traversal and mutation operations with arrays.

📄️ Collection functions

Manipulate different collections.

📄️ Date functions

Calculate and manipulate dates and time.

📄️ Lang functions

General purpose functions.

📄️ Math functions

Perform mathematical calculations.

📄️ Number functions

Manipulate numbers.

📄️ Object functions

Perform various manipulation and mutation operations with objects.

📄️ String functions

Manipulate strings.

📄️ Util functions

Various utility functions.