How unescape strings in json with ruby?

Question

Here is json string:

 {
    "app":"${host}\":\"${post}"
 }

How unwrap strings? Eg how to produce this:

{
    app:${host}":"${post}
}

Leading and trailing double quotes are deleted, escaped double quotes become unescaped.

How to do this with ruby?

Also

In java I can use appache commons StringEscapeUtil.unescapeJson Is there analog in ruby?

Important

1. yep, the result will not be valid json file. This is expected.
2. I can use something like string.replace("\\"", "") and string.replace("\\\\\\"", "") but it would be nice to use some out-of-the-box function (if it is).

Answer 1

require 'json'

str =<<'END_OF_STRING'
{
    "app":"${host}\":\"${post}"
}
END_OF_STRING

puts str
puts str.gsub(/[\\]" | ["]/x, '\"' => '"', '"' => '')

--output:--
{
    "app":"${host}\":\"${post}"
}
{
    app:${host}":"${post}
}