how to build json without escaping new line? - bash

Question

I run jq from bash and all my new lines are escaped
release_message="\`\`\`a\na\n\`\`\`"
query=$(jq -n \
--arg message $release_message \
"{text:\$message}"
);
echo "query $query"
result
query {
"text": "```a\\na\\n```"
}
How to prevent extra escape from jq?

Answer 1

You can either encode your input in JSON yourself or let jq do it
option 1 : encode yourself
release_message='"```a\na\n```"'
jq -n --argjson message "$release_message" '{text:$message}'
# or :
# echo "$release_message" | jq '{text:.}'
Have bash produce a valid JSON string (note : quotes-enclosed), pass through the standard input or with --argjson.
option 2 : let jq encode the string
release_message='```a
a
```'
jq --arg message "$release_message" '{text:$message}'
# or :
# echo "$release_message" | jq -R --slurp '{text:.}'
Have bash produce the literal string, pass with --arg or specify --raw-input/-R to have the input encoded in JSON, plus --slurp so that the multiple lines are considered as a single string.

Answer 2

Since you're using bash, it's generally best to use single quotes unless you want string interpolation. Consider, for example:
release_message='```a\na\n```'
query=$(jq -n \
--arg message "$release_message" \
'{text: $message }'
);
echo "query $query"
You might want to consider using $'....':
release_message=$'```a\na\n```'
Using gsub
Depending on what your actual goals are, you might want to use gsub, e.g.
release_message='```a\na\n```'
query=$(jq -n \
--arg message "$release_message" \
'{text: ($message | gsub("\\n";"\n")) }'
);
echo "query $query"
produces:
query {
"text": "```a\\na\\n```"
}