How to format a bash array as a JSON array

Question

I have a bash array

X=(\"hello world\" \"goodnight moon\")

That I want to turn into a json array

[\"hello world\", \"goodni         


        

Answer 1

If the values do not contain ASCII control characters, which have to be escaped in strings in valid JSON, you can also use sed:

$ X=("hello world" "goodnight moon")
$ printf %s\\n "${X[@]}"|sed 's/["\]/\\&/g;s/.*/"&"/;1s/^/[/;$s/$/]/;$!s/$/,/'
["hello world",
"goodnight moon"]

If the values contain ASCII control characters, you can do something like this:

X=($'a\ta' $'a\n\\\"')
for((i=0;i<${#X[@]};i++));do
  [ $i = 0 ]&&printf \[
  printf \"
  e=${X[i]}
  e=${e//\\/\\\\}
  e=${e//\"/\\\"}
  for((j=0;j<${#e};j++));do
    c=${e:j:1}
    if [[ $c = [[:cntrl:]] ]];then
      printf '\\u%04x' "'$c"
    else
      printf %s "$c"
    fi
  done
  printf \"
  if((i<=${#X[@]}-2));then
    printf ,
  else
    printf \]
  fi
done