DataWeave Interview Question: Reverse an Array After Combining Its Elements

This article will help you practice your DataWeave skills in MuleSoft. Use the article as a tutorial for learning more about DataWeave.

Let's get started. 

Input:

[

"uat", ["sit", "qa", "prod"]

]

Output:

[

  "prod",

  "qa",

  "sit",

  "uat"

]

Let's talk about the solution now.

In the first step, we will combine all the elements of an array into a single array using flatten function.

Step 1 Code:

DataWeave Script

%dw 2.0

output application/json

var combinedPayload = (flatten(payload))

---

combinedPayload

Step 1 Output:

[

  "uat",

  "sit",

  "qa",

  "prod"

]

In the second step, we will reverse the contents of an array using the range selector.

Step 2 Code:

DataWeave Script

%dw 2.0

output application/json

var combinedPayload = (flatten(payload))

---

combinedPayload[(sizeOf(combinedPayload)) -1 to 0]

Step 2 Output:

[

  "prod",

  "qa",

  "sit",

  "uat"

]

We have used sizeOf function to get the size of our combinedPayload along with the range selector to get the array in reverse format.

Happy Learning!