Split a JSON file into separate files

Question

I have a large JSON file that is an object of objects, which I would like to split into separate files name after object keys. Is it possible to achieve this using jq or any

Answer 1

Here's a solution that requires only one call to jq:

jq -cr 'keys[] as $k | "\($k)\n\(.[$k])"' input.json |
  while read -r key ; do
    read -r item
    printf "%s\n" "$item" > "/tmp/$key.json"
  done

It might be faster to pipe the output of the jq command to awk, e.g.:

jq -cr 'keys[] as $k | "\($k)\t\(.[$k])"' input.json |
  awk -F\\t '{ print $2 > "/tmp/" $1 ".json" }'

Of course, these approaches will need to be modified if the key names contain characters that cannot be used in filenames.

Answer 2

This should give you a start:

for f in `cat input.json | jq -r 'keys[]'` ; do
  cat input.json | jq ".$f" > $f.json
done

or when you insist on more bashy syntax like some seem to prefer:

for f in $(jq -r 'keys[]') ; do
  jq ".[\"$f\"]" < input.json > "$f.json"
done < input.json

Answer 3

Is it possible to achieve this using jq or any other off-the-shelf tools?

It is. Xidel can also do what you want:

for f in $(xidel -s input.json -e '$json()'); do
  xidel -s input.json -e '$json("'$f'")' > $f.json
done