This is a small tool written in go to convert json to yaml reading from STDIN and writing to STDOUT. The heavy lifting is actually done by ghodss/yaml and gopkg.in/yaml.v2.
To install simply
go install github.com/brancz/gojsontoyaml@latest
Simply pipe a json string into gojsontoyaml and it will print the converted yaml string to STDOUT.
$ echo '{"test":"test string with\\nmultiple lines"}' | gojsontoyaml
test: |-
test string with
multiple lines
You may ask yourself why this was developed. The answer is simple, when I wrote this there was no simple to use binary for this purpose that supported yaml multiline strings. All alternatives out there that I tried kept line breaks in the string rather than making use of the yaml multiline strings.