Bash find execute process with output redirected to a different file per each - bash

Question

I'd like to run the following bash command for every file in a folder (outputting a unique JSON file for each processed .csv), via a Makefile:
csvtojson ./file/path.csv > ./file/path.json
Here's what I've managed, I'm struggling with the stdin/out syntax and arguments:
find ./ -type f -name "*.csv" -exec csvtojson {} > {}.json \;
Help much appreciated!

Answer 1

You're only passing a single argument to csvtojson -- the filename to run.
The > outputfile isn't an argument at all; instead, it's an instruction to the shell that parses and invokes the relevant command to connect the command's stdout to the given filename before actually starting that command.
Thus, above, that redirection is parsed before the find command is run -- because that's the only place a shell is involved at all.
If you want to involve a shell, consider doing so as follows:
find ./ -type f -name "*.csv" \
-exec sh -c 'for arg; do csvtojson "$arg" >"${arg}.json"; done' _ {} +
...or, as follows:
find ./ -type f -name '*.csv' -print0 |
while IFS= read -r -d '' filename; do
csvtojson "$filename" >"$filename.json"
done
...or, if you want to be able to set shell variables inside the loop and have them persist after its exit, you can use a process substitution to avoid the issues described in BashFAQ #24:
bad=0
good=0
while IFS= read -r -d '' filename; do
if csvtojson "$filename" >"$filename.json"; then
(( ++good ))
else
(( ++bad ))
fi
done < <(find ./ -type f -name '*.csv' -print0)
echo "Converting CSV files to JSON: ${bad} failures, ${good} successes" >&2
See UsingFind, particularly the Complex Actions section and the section on Actions In Bulk.