Format nested JSON input using JQ? - json

Question

I am trying to convert the sample input below into the output below using jq:
Input JSON
"elements": [
{
"type": "CustomObjectData",
"id": "2185",
"fieldValues": [
{
"type": "FieldValue",
"id": "169",
"value": "9/6/2017 12:00:00 AM"
},
{
"type": "FieldValue",
"id": "190",
"value": "ABC"
}
]
},
{
"type": "CustomObjectData",
"id": "2186",
"contactId": "13",
"fieldValues": [
{
"type": "FieldValue",
"id": "169",
"value": "8/31/2017 12:00:00 AM"
},
{
"type": "FieldValue",
"id": "190",
"value": "DEF"
}
]
}
]
Desired Output (group by id)
Essentially trying to extract "value" field from each "fieldValues" object and group them by "id"
{
"id:"2185",
"value": "9/6/2017 12:00:00 AM",
"value": "ABC"
},
{
"id:"2186",
"value": "8/31/2017 12:00:00 AM",
"value": "DEF"
}
What jq syntax should i use to achieve this? Thanks very much!!

Answer 1

Assuming the input shown in the Q has been modified in the obvious way to make it valid JSON, the following filter will produce the output as shown below, that is, a stream of valid JSON values that is similar to the allegedly expected output included in the Q. If a single array is desired, one possibility would be to wrap the program in square brackets.
program.jq
.elements[]
| {id, values: [ .fieldValues[].value] }
Output
{
"id": "2185",
"values": [
"9/6/2017 12:00:00 AM",
"ABC"
]
}
{
"id": "2186",
"values": [
"8/31/2017 12:00:00 AM",
"DEF"
]
}
Producing CSV
One of many possibilities:
.elements[]
| [.id] + [.fieldValues[].value]
| #csv
With the -r command-line option, this produces the following CSV:
"2185","9/6/2017 12:00:00 AM","ABC"
"2186","8/31/2017 12:00:00 AM","DEF"