Rename a group of files to a string that exists inside each one

Question

I have a group of json files. Each file contains one json object and they all have the same schema. There is a field in the json that I want to rename the file to. How can I do that?

I came up with this solution:

find . -name '*.json' | xargs -i mv {} $(cat {} | jq '.billingAccountList[0]' | tr -d \").json

But it doesn't work, because cat is trying to interpret the {}. I was hoping the xargs would interpret it instead. It gives me this error:

cat: {}: No such file or directory

Answer 1

Use a loop to handle the files one by one.

For instance, with while read:

find . -name '*.json' | while read fname; do
    newname=$(jq -r '.billingAccountList[0]' "${fname}").json
    mv "${fname}" "${newname}"
done

Using for might be possible, but it's more sensitive to spaces in the names of the files:

for fname in $(find . -name '*.json'); do
    ... (same as above) ...

Also note that you're moving the files into the current directory, as the original path is being stripped, so if you want to keep the directory structure:

find . -name '*.json' | while read fname; do
    fdir=$(dirname "${fname}")
    newname=$(jq -r '.billingAccountList[0]' "${fname}").json
    mv "${fname}" "${fdir}/${newname}"
done

UPDATE: Using jq -r as suggested by @steeldriver. Thanks!

Answer 2

You should be able to use jq -r to output raw (unquoted) strings - rather than stripping quotes with tr

Also I'm going to assume that you want to rename the files relative to their parent directory (so, for example, if the value .billingAccountList[0] in path/to/file.json is foo, then the new name should be path/to/foo.json rather than foo.json), and that your implementation of find has a -execdir

So I'd do something like

find . -name '*.json' -execdir sh -c '
  echo mv -- "$1" "$(jq -r ".billingAccountList[0]" < "$1").json"
' find-sh {} \;

or (at least with GNU find) more efficiently

find . -name '*.json' -execdir sh -c '
  for f; do echo mv "$f" "$(jq -r ".billingAccountList[0]" < "$f").json"; done
' find-sh {} +

Remove the echo once you are satisfied that it's doing the right thing.

Answer 3

With zsh's zmv (for better handling of conflicts):

autoload zmv
zmv -n '(**/)*.json(#qD.)' '$1$(jq -r '.billingAccountList[0]' < $f).json

(remove -n when happy).