JOLT: A Complete Guide to JSON Transformation (From Basics to Advanced)

Introduction JOLT (JsOn Language for Transform) is a language used to transform JSON structures and is commonly found in integration layers where payloads need to be normalized, reshaped, enriched, or reduced before being consumed by downstream systems. This article was written as a detailed learning reference for developers with little or no prior experience with JOLT. The objective is to start from the basics and gradually move to more advanced behavior, preserving the details that are usually necessary to truly understand how JOLT works in practice. For testing all examples contained in this article: JOLT playground JOLT — JsOn Language for Transform JOLT is a language used for the transformation of JSON. It uses the following basic structure: [ { "operation": "", "spec": {} } ] Where: operation: defines the type of transformation that will be applied spec: field where the transformation is defined []: the basic JOLT structure is also a JSON list, therefore we can chain multiple ope