JQ transform JSON doc

I have JSON file with below format

{
    "key1": ["val1", "val2"],
    "key2": ["v1", "v2"]
}

I want to transform it into

{
    "key1": ["val1-v1", "val2-v2"],
    "key2": ["v1", "v2"]
}

How can I acheive this using jq in linux environment?

>Solution :

You could use to_entries to generate an array of indices and values. Use the indices to index into the other key, stored in a variable for reference:

jq '. as {$key2} | .key1 |= [to_entries[] | .value + "-" + $key2[.key]]' data.json

Demo

If the arrays aren’t big, you could also use the less efficient transpose filter to zip them:

jq '.key1 = [map(.) | transpose[] | join("-")]' data.json

Demo

Output of both:

{
  "key1": [
    "val1-v1",
    "val2-v2"
  ],
  "key2": [
    "v1",
    "v2"
  ]
}