Efficiently Transform JSON with DataWeave

Problem:

Updating individual properties within deeply nested JSON objects using the update function can be inefficient for large datasets.
The update function may traverse the entire object tree to locate a specific property, leading to performance issues.

Solution:

Leverage DataWeave operators like map, filter, and reduce to efficiently transform JSON.
These operators often provide better performance for large datasets due to their simpler logic and easier debugging.
Break down complex transformations into smaller, more manageable steps.

Implementation:

This DataWeave 2.0 script demonstrates how to reformat JSON keys:

%dw 2.0output application/json// Function to recursively reformat keysfun formatKeys(inBound, fromSymbol: String, toSymbol: String) =     inBound match {        case is Array -> inBound map (formatKeys($, fromSymbol, toSymbol))        case is Object -> inBound mapObject (            (value, key) -> (key replace "$(fromSymbol)" with "$(toSymbol)") ++ value        )        else -> inBound    }// Example usage: Replace underscores with hyphensformatKeys(payload, "_", "-")

Explanation:

formatKeys function:
- Recursively handles arrays and objects.
- For arrays, it applies formatKeys to each element.
- For objects, it uses mapObject to iterate through key-value pairs:
  - Replaces fromSymbol with toSymbol in the key.
  - Maintains the original value.
Example usage:
- Calls formatKeys with payload, _ (from symbol), and - (to symbol).
- This effectively replaces all underscores in keys with hyphens.

Benefits:

Improved performance: Efficiently handles large datasets compared to the update function.
Clear and concise: Easy to understand and maintain.
Flexibility: Easily adaptable to different key replacement scenarios.

Example:

Input:

{  "id": "0001",  "type_1": "donut",  "name": "Cake",  "image": {    "url_link": "images/0001.jpg",    "width": 200,    "height": 200  }}

Output:

{
  "id": "0001",
  "type-1": "donut",
  "name": "Cake",
  "image": {
    "url-link": "images/0001.jpg",
    "width": 200,
    "height": 200
  }
}

]]>

Efficiently Transform JSON with DataWeave | MuleSoft Guide

Contact Form