Parse a multidimensional json array using bash

Question

I'd like to iterate over a multidimensional json array in bash but haven't found a solution.

Here is what the multidimensional array would look like:

{
    "FILES": [
      [ "file1.yaml", "file2.yaml", "file3.yaml" ],
      [ "file1.json", "file2.json" ]
    ]
}

I'd like to convert each array into a string that will eventually be the input to a command.

So something like:

#!/bin/bash

Json_Array=$(cat <<EOF
{
    "FILES": [
      [ "file1.yaml", "file2.yaml", "file3.yaml" ],
      [ "file1.json", "file2.json" ]
    ]
}
EOF
)

function runCmd ()
{
  echo "command $1"
}

function runCmds ()
{
  jq -c '.FILES' <<< "$Json_Array" | while read i; do
    runCmd "$(echo $i | jq .)"
  done
}

runCmds

So the output should be:

command file1.yaml file2.yaml file3.yaml
command file1.json file2.json

Thank you for any help!

Answer 1

Insert the command with any options at the start of each array, then pass each array through @sh to create shell code. Evaluate the shell code.

Here, I'm also showing how to insert extra arguments to the command (-a and -b hello):

eval "$( jq -r '.FILES | map([ "command", "-a", "-b", "hello", .[] ])[] | @sh' file.json )"

Given the JSON in the question, this would execute the following commands in the shell:

'command' '-a' '-b' 'hello' 'file1.yaml' 'file2.yaml' 'file3.yaml'
'command' '-a' '-b' 'hello' 'file1.json' 'file2.json'

If you have your JSON document in some variable, $json, then use

eval "$( jq -r '.FILES | map([ "command", "-a", "-b", "hello", .[] ])[] | @sh' <<<"$json" )"