The mapObject
function is used to transform the data contained in an object. It does this by iterating over each key/value pair in the object and applying a transformation to each key and value. It takes in an Object, and a lambda that takes in 3 parameters, a value, key, and index, and returns a new Object. Finally, the entire function returns an Object.
mapObject(Object<K,V>, (V,K,Number) -> Object): Object
mapObject<K, V>(@StreamCapable object: { (K)?: V }, mapper: (value: V, key: K, index: Number) -> Object): Object
We use mapObject
when we want to change the keys and/or values on an Object to be something else.
This example iterates over the input { "a":"b","c":"d"}
and uses the anonymous mapper function ((value,key,index) → { (index) : { (value):key} }
) to invert the keys and values in each specified object and to return the indices of the objects as keys. The mapper uses named parameters to identify the keys, values, and indices of the input object. Note that you can write the same expression using anonymous parameters, like this: {"a":"b","c":"d"} mapObject { ($$$) : { ($):$$} }
%dw 2.0
output application/json
---
{"a":"b","c":"d"} mapObject (value,key,index) -> { (index) : { (value):key} }
{ "0": { "b": "a" }, "1": { "d": "c" } }
{
"firstName": "Avery",
"lastName": "Chance",
"age": 56,
"occupation": "Physicist"
}
%dw 2.0
output json
---
payload mapObject (value, key, index) -> {
(upper(key)): value
}
{
"FIRSTNAME": "Avery",
"LASTNAME": "Chance",
"AGE": 56,
"OCCUPATION": "Physicist"
}
The parentheses around
upper(key)
are required to make the key dynamic, as seen in previous sections.
If you like my post please follow me to read my latest post on programming and technology.
Find the length of the longest absolute path to a file within the abstracted file…
You manage an e-commerce website and need to keep track of the last N order…
You are given a stream of elements that is too large to fit into memory.…
The formula for the area of a circle is given by πr². Use the Monte…
Given an integer k and a string s, write a function to determine the length…
There is a staircase with N steps, and you can ascend either 1 step or…