How to construct associative Bash array from JSON hash?

Question

The question is exactly the opposite of Constructing a json hash from a bash associative array. Given the following JSON:

{
    "a": "z",
    "b": "y",
    "c": "x"
}

I would like to have an associative Bash array.

Answer 1

A NUL-delimited stream is the safest approach:

input='{"a":"z","b":"y","c":"x"}'
declare -A data=()

while IFS= read -r -d '' key && IFS= read -r -d '' value; do
    data[$key]=$value
done < <(jq -j 'to_entries[] | (.key, "\u0000", .value, "\u0000")' <<<"$input")

Note the use of jq -j, which suppresses quoting (like -r), but also suppresses the implicit newline between items, letting us manually insert a NUL instead.

See the discussion in https://github.com/stedolan/jq/issues/1271 (a ticket explicitly requesting a NUL-delimited output mode), wherein this idiom was first suggested.

Answer 2

You can do it like this :

while IFS=':' read k v 
do 
    dict[$k]="$v"
done <<< "$( sed -E "s/(\"|,|{|})//g; /^ *$/d; s/^ *//g" input.txt )"

echo "The value of key 'a' is : ${dict[a]}"

Hope it helps you!