Escape jq query and save output in a bash variable

Question

I am trying to save the output of the following command in a bash variable in a script. But no matter how hard i try, i am unable to escape the quotes correctly.

Here is the command whose output i want to save in a variable.

$ echo '[{"field":"fieldA","bucket":["a","b","c"]},{"field":"fieldB","bucket":["a","b","c","d"]}]' | jq -r '.[]|{field, bucketText: .bucket|join(", ")}|join(" found in bucket: ")'
fieldA found in bucket: a, b, c
fieldB found in bucket: a, b, c, d

And here is my attempt in my script file

#!/bin/bash

INPUT='[{"field":"fieldA","bucket":["a","b","c"]},{"field":"fieldB","bucket":["a","b","c","d"]}]'

OUTPUT_LINES="$(echo ${INPUT} | jq -r '.[]|{field, bucketText: .bucket|join(\", \")}|join(\" found in bucket: \")')"

printf "%s\n" "${OUTPUT_LINES}"

Answer 1

You may use this script:

#!/bin/bash

input='[{"field":"fieldA","bucket":["a","b","c"]},{"field":"fieldB","bucket":["a","b","c","d"]}]'

output="$(jq -r '.[]|{field, bucketText: .bucket|join(", ")}|join(" found in bucket: ")' <<< "$input")"

printf "%s\n" "$output"

Output:

fieldA found in bucket: a, b, c
fieldB found in bucket: a, b, c, d

Suggested changes:

• No need to escape double quote inside single quoted jq commands
• Recommended to use lowercase variables instead of all uppercase
• Avoid pipeline and use here-string in jq command to avoid unnecessary sub-shell creation