JSON Transformation using JOLT: Nested Array and Concatenation - json

Question

I have the following input JSON
[
{
"name": "Project1",
"Addresses": [
[
"B24",
"Niyam Street",
"67897",
"New York"
],
[
"A14",
"Prinston Str",
"London"
]
]
},
{
"name": "Project2",
"Addresses": [
[
"123",
"Portland Street",
"234"
],
[
"Lalbag",
"Kolaba"
],
[
"8th Avenue",
"3rd Signal"
]
]
}
]
I would like to transform it into like the below:
[
{
"name": "Project1",
"Addresses": [
"B24 Niyam Street 67897 New York",
"A14 Prinston Str London"
]
},
{
"name": "Project2",
"Addresses": [
"123 Portland Street 234",
"Lalbag Kolaba",
"8th Avenue 3rd Signal"
]
}
]
The Addresses attribute value is a two-dimensional array of dynamic size.
Could you please help me with a valid jolt spec or some hints to achieve it? I am lost. Thank you so much.

Answer 1

You can use combination of shift and modify transformations such as
[
{
"operation": "shift",
"spec": {
"*": {
"*": "&", // the attributes other than "Addresses"
"Addresses": {
"*": "&1.&2.&" // determine the objects with indexed key names(0,1,2...) where &2 represents going two level up the tree to get the outermost indices of the objects of the main array, & for indices of the "Addresses" array, and &1 to keep the key name "Addresses" to transfer to the upcoming specs
}
}
}
},
{
"operation": "modify-overwrite-beta",
"spec": {
"*": {
"*": {
"*": "=join(' ',#(1,&))" // concatenate all components of each array respectively at once
}
}
}
},
{
// combine the attributes back again
"operation": "shift",
"spec": {
"*": {
"*": "[&].&1"
},
"A*": {
"*": {
"*": "[&1].&2"
}
}
}
}
]
the demo on the site http://jolt-demo.appspot.com/ is