JSON: use jq to edit specific values in nested arrays - arrays

Question

I'm trying to update values within an array inside an array using the utility jq. I've pasted the sample json below.
More specifically: Within the sheets array, and then within the formulas array, I'd like to change each columnName with a value of "MONTH" to "YEAR". I'd like to do the same for within the sheets array, within the columnStyles array, change each incidence of "MONTH" also to "YEAR"
This jq filter gets me the list of columnNames.
.sheets[1] | .formulas[] | .columnName
How can I edit the entire file in place by just updating the values I want? Do I use map with if?
And what if I wanted to edit a portion of a value? For example, in a forumlaString property, just changing the part of the string that contains MONTH but leaving the rest intact?
{
"version": "6.1.1",
"className": "xyz",
"sheets": [
{
"name": "Pass1",
"sheetId": "95e6c2cd-abbe-46c1-8012-bdf37438b9b7",
"keep": true,
"formulas": [
{
"columnName": "SAMPLE_PROVIDER",
"columnId": "0",
"columnIndex": 0,
"formulaString": "\u003dGROUPBY(#Raw!SAMPLE_PROVIDER)"
},
{
"columnName": "MONTH",
"columnId": "1",
"columnIndex": 1,
"formulaString": "\u003dGROUPBY(#Raw!MONTH)"
}
],
"columnStyles": [
{
"columnId": "0",
"name": "SAMPLE_PROVIDER",
"width": 206,
"thousandSeparator": true
},
{
"columnId": "1",
"name": "MONTH",
"width": 100,
"thousandSeparator": true
}
],
"nextColumnId": 2
},
{
"name": "Transform1",
"sheetId": "49071c1c-fa84-4ae3-92c1-b63175a6b26c",
"keep": true,
"formulas": [
{
"columnName": "SAMPLE_PROVIDER",
"columnId": "0",
"columnIndex": 0,
"formulaString": "\u003d#Pass1!SAMPLE_PROVIDER"
},
{
"columnName": "MONTH",
"columnId": "1",
"columnIndex": 1,
"formulaString": "\u003d#Pass1!MONTH"
}
],
"columnStyles": [
{
"columnId": "0",
"name": "SAMPLE_PROVIDER",
"width": 179,
"thousandSeparator": true
},
{
"columnId": "1",
"name": "MONTH",
"width": 100,
"thousandSeparator": true
}
],
"nextColumnId": 3
}
],
"advancedSchedulingInUse": true,
"errorHandlingMode": "IGNORE"
}

Answer 1

To change the columnName field in the desired containers, you can use
jq '(.sheets[] | .formulas[]? | .columnName | select(.=="MONTH")) |= "YEAR"' tmp.json
(The ? avoids an error if there is no key formula.)
To replace MONTH with YEAR in formula strings, replace each formulaString value with a possible modified string returned by sub.
jq '(.sheets[] | .formulas[]? | .formulaString) |= sub("MONTH"; "YEAR")' tmp.json
(sub requires jq 1.5, compiled with the Oniguruma library.)
To combine these into a single jq filter? I'm not sure yet; I have only a tenuous understanding of why either one alone works.

Answer 2

It looks like you're updating more than just fields in the formulas arrays, but a little bit of everything.
If you want to indiscriminately change all occurrences of the string "MONTH" to "YEAR", you could do this:
(.. | strings) |= sub("MONTH"; "YEAR")

Answer 3

This may be a task for walk/1.
(If your jq does not have walk/1, then you can copy its definition from https://github.com/stedolan/jq/blob/master/src/builtin.jq)
For example, if you want to change "MONTH" to "YEAR" whenever "MONTH" appears as the value of a key in an object, then the following would do the job:
jq 'walk(if type == "object"
then with_entries(.value |= (if . == "MONTH" then "YEAR" else . end))
else . end)' input.json
Equivalently:
jq 'walk(if type == "object"
then with_entries(if .value == "MONTH" then .value = "YEAR" else . end)
else . end)' input.json
These can easily be modified in accordance with similar requirements.