Create a JSON object using a cli tool: jq

1 min read | by Jordi Prats

We can define jq tool as what's sed but for JSON data: We can use it for multiple purposes, for example to create a valid JSON object.

Let's assume we want to create a JSON containing a multi-line string, we can simulate it like follows or just use some file with cat:

$ echo -e "multi\nline"
multi
line

In order to generate a string from it that can be used on a JSON object we can use jq to generate the object from a template like this:

$ jq --null-input --arg input "$(echo -e "multi\nline")" '{ "multi-line-string": $input }'
{
  "multi-line-string": "multi\nline"
}

By using a different command as an argument we can transform a file into a multi-line string:

$ jq --null-input --arg input "$(cat multiline-file.txt)" '{ "multi-line-string": $input }'
{
  "multi-line-string": "multi\nline"
}

Posted on 07/12/2022