Extract data from nested JSON and convert to TSV

Question

I'm looking at parsing nested json. For the example below, I know that it appears on Github - however due to sensitivity I cannot post my actual data on here.

I've Been looking at jq for formatting, and can pull each component out, but cannot merge them together such that it looks like the below.

BEcuase of software restrictions, I cannot use 3rd party code.

input:

 { "asgs": [ { "name": "test1", "instances": [ {"id": "i-9fb75dc", "az": "us-east-1a", "state": "InService"}, {"id": "i-95393ba", "az": "us-east-1a", "state": "Terminating:Wait"}, {"id": "i-241fd0b", "az": "us-east-1b", "state": "InService"} ] }, { "name": "test2", "instances": [ {"id": "i-4bbab16", "az": "us-east-1a", "state": "InService"}, {"id": "i-417c312", "az": "us-east-1b", "state": "InService"} ] } ] }

output:

test1   i-9fb75dc       us-east-1a      InService
test1   i-95393ba       us-east-1a      Terminating:Wait
test1   i-241fd0b       us-east-1b      InService
test2   i-4bbab16       us-east-1a      InService
test2   i-417c312       us-east-1b      InService

EDIT: Current code is such that I loop through all the instances of instances using and then append the names. For example:

cat sampleData.json | jq -c '.' | while read i; do
echo $i, & jq '.instances' sampleData.json
done

Answer 1

A slight shorter (though marginally more complex) version of @anubhava's answer:

jq -r '.asgs[] | .name as $n | (.instances[] | [$n, .id, .az, .state] | @tsv)' file.json

This "remembers" each name before producing a tab-separated line for each instance, inserting the correct name in each row.

Answer 2

You may use this jq :

jq -r '.asgs[] | .name + "\t" + (.instances[] | .id + "\t" + .az + "\t" + .state)' file.json

test1   i-9fb75dc   us-east-1a  InService
test1   i-95393ba   us-east-1a  Terminating:Wait
test1   i-241fd0b   us-east-1b  InService
test2   i-4bbab16   us-east-1a  InService
test2   i-417c312   us-east-1b  InService

Answer 3

You can use a generic map to create an extra entry per-instance:

jq -r '.asgs[] | [.name] + (.instances[] | map(.)) | @tsv'