How does the jolt wildcards work for RHS? - json

Question

I'm trying to understand the working of '#' wild card.
I have used the '#' in the spec while preparing the productList and it works and I got the output as per my expectation. But I'm not sure about the working of it.
Can anyone please help me to understand the working of it?
Here is the input JSON
{
"orders": [
{
"order_parts": [
{
"id": "0001",
"items": [
{
"id": "00101",
"goodIdentificationList": [
{
"goodIdentificationTypeId": "UPCA",
"idValue": "42684666380437"
},
{
"idValue": "V-ASHBY",
"goodIdentificationTypeId": "SHOPIFY_PROD_SKU"
}
],
"productName": "BLACK / 6 / 809"
},
{
"id": "00102",
"goodIdentificationList": [
{
"goodIdentificationTypeId": "SHOPIFY_PROD_ID",
"idValue": "42684666380437"
},
{
"idValue": "V-ASHBY",
"goodIdentificationTypeId": "UPCA"
}
],
"productName": "BLACK / 6 / 809"
}
]
},
{
"id": "0002",
"items": [
{
"id": "00103",
"goodIdentificationList": [
{
"goodIdentificationTypeId": "SHOPIFY_PROD_ID",
"idValue": "42684666380437"
},
{
"idValue": "V-ASHBY",
"goodIdentificationTypeId": "UPCA"
}
],
"productName": "BLACK / 6 / 809"
}
]
}
]
}
]
}
Expected by the below spec:-
Check every map of goodIdentificationList, get the idValue where goodIdentificationTypeId - UPCA, and put in the productList as gtin.
Get the id from the items list and put it in the productList as an itemId.
Get the productName from the items list and put it in the productList as a name.
Jolt Spec is like below
[
{
"operation": "shift",
"spec": {
"orders": {
"*": {
"order_parts": {
"*": {
"items": {
"*": {
"goodIdentificationList": {
"*": {
"goodIdentificationTypeId": {
"UPCA": {
"#(2,idValue)": "[&5].productList.[#8].gtin"
}
}
}
},
"id": "[&1].productList.[#4].itemId",
"productName": "[&1].productList.[#4].name"
}
}
}
}
}
}
}
},
{
"operation": "shift",
"spec": {
"*": {
"productList": {
"*": "productList.[]"
}
}
}
}
]
By the above spec, I'm able to prepare the productList as I was expecting.
But want to understand the working of '#' here.
Output JSON
{
"productList" : [ {
"itemId" : "00101",
"name" : "BLACK / 6 / 809"
}, {
"itemId" : "00103",
"name" : "BLACK / 6 / 809"
}, {
"itemId" : "00102",
"name" : "BLACK / 6 / 809"
} ]
}
Any help will be appreciated.
Thanks!

Answer 1

You principally need this spec
[
{
"operation": "shift",
"spec": {
"order*": {
"*": {
"order*": {
"*": {
"items": {
"*": {
"id": "&3.&1.&",
"prod*": "&3.&1.&"
}
}
}
}
}
}
}
},
{
"operation": "shift",
"spec": {
"*": {
"*": "productList[]"
}
}
}
]
in which, the combination of the indexes of "items" array(&1) vs. the indexes of "order_parts" array(&3) handles separation of three individual objects, and then then tiding up innermost part while tagging the desired value(productList), and combining those newly generated objects will spontaneously form an array.
Replacement of
"id": "&3.&1.&",
"prod*": "&3.&1.&"
with
"id": "&3[&1].&",
"prod*": "&3[&1].&"
or
"id": "&3[#2].&",
"prod*": "&3[#2].&"
would handle exactly the same for this current case. But if there was no array the identifiers [&1] or [#2] would produce square brackets. The difference for right-hand-size usage of them is [&1] will traverse {, while [#2] will traverse both { and the current : characters in order to reach the target within the current tree, and [&1] will use indexes 0,1,2, which starts from zero, everytime and this will generate some null components for generated arrays for some cases, while [#2] won't. Eg. On the RHS of the spec, # is only valid in the the context of an array, like "[#2]".What "[#2]" means is, go up the three levels(including the colon at the current level) and ask that node how many matches it has had, and then use that as an index in the arrays.