Скачать или смотреть Join a JSON Object and Array in DataWeave

Learn how to effectively merge a JSON object and an array in DataWeave, ensuring all values are included for robust data integration.
---
This video is based on the question https://stackoverflow.com/q/74200031/ asked by the user 'Andy' ( https://stackoverflow.com/u/4771802/ ) and on the answer https://stackoverflow.com/a/74200210/ provided by the user 'aled' ( https://stackoverflow.com/u/721855/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: Join a JSON Object and Array in DataWeave

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Mastering DataWeave: Joining a JSON Object and Array

In the world of data transformations, working with JSON data structures is a common task. However, problems can arise when trying to merge different types of JSON structures, such as a JSON object and a JSON array. This guide will walk you through a scenario where you're required to join a JSON object with an array in DataWeave, ensuring all relevant fields are present in the final output.

Understanding the Problem

Let's break down the problem:

Input Data: You have two JSON structures:

A JSON Object (var1)

A JSON Array (var2), which can contain either zero or one JSON object.

Example JSON Structures

JSON Object (var1):

[[See Video to Reveal this Text or Code Snippet]]

JSON Array (var2):

Could be an array containing one object:

[[See Video to Reveal this Text or Code Snippet]]

Or it could be an empty array:

[[See Video to Reveal this Text or Code Snippet]]

Desired Output

Your goal is to produce a single JSON object that contains fields from both structures, such that the output always looks like this:

[[See Video to Reveal this Text or Code Snippet]]

Note: Fields policyName1 to policyName6 should be present in the output regardless of the content in var2.

Crafting the Solution

To accomplish this data transformation using DataWeave, we need to break down the solution into the following steps:

Step 1: Initialize Default Policies

First, create a default object for policies which will ensure that all six policy fields are included, even if var2 is empty.

[[See Video to Reveal this Text or Code Snippet]]

Step 2: Reduce the Array to an Object

Next, make use of the reduce() function on the array (var2). This will help in combining the array items (if present) into a single object.

[[See Video to Reveal this Text or Code Snippet]]

Step 3: Merge Objects

Finally, merge the default policies with the JSON object (var1) and the reduced array object. For this, use the mergeWith() function to ensure correct formatting and inclusion of all necessary fields.

[[See Video to Reveal this Text or Code Snippet]]

Complete DataWeave Code

Here's how the complete DataWeave script looks:

[[See Video to Reveal this Text or Code Snippet]]

Output

After executing the above DataWeave code, the output will be:

[[See Video to Reveal this Text or Code Snippet]]

Conclusion

By following the steps outlined above, you can effectively join a JSON object and a JSON array in DataWeave. This approach not only ensures that required fields are included, but also simplifies the integration of data structures commonly used in data processing scenarios. Whether you're dealing with APIs, data pipelines, or application integrations, mastering this technique is invaluable.

Feel free to share your thoughts or any questions you may have in the comments below!