Snippet to find string files of a given filename

find . -name config.rb -print0 | xargs -0 grep 'search-thing'

Find to find files newer than

find . -newermt '14 days ago' ## minutes/hours etc.. see date input formats

Json file processing unix tool

When you to view/edit a large json file on the unix command line you can use the jq tool

pkg install jq

It can be used to pretty-print json

jq . file.json

Or to perform queries on it. (https://stedolan.github.io/jq/manual/)

Quick way to delete to many files in the current directory (argument list to long)

 find . -type f -delete

When it's really you can use the folowing perl command to delete all files. (I had a situation with 3 milion files)

cd /folder/to/delete-files
perl -e 'for(<*>){((stat)[9]<(unlink))}'

Reference: https://www.slashroot.in/which-is-the-fastest-method-to-delete-files-in-linux

Cron Job to clear Rails Cache

The rails file cache is something that keeps growing.
Here are some 'handy' snippets.

Delete all files older then 7 days. (replace -delete with -print to test it)

find ./tmp/cache/ -type f -mtime +7 -delete

Delete all empty folders. (mindepth prevents the deletion of the root folder)

find ./tmp/cache/ -type d -empty -delete -mindepth 1

The whenever.rb I use

job_type :command_in_path, "cd :path && :task :output"

every :day, at: "0:40" do
  command_in_path "find ./tmp/cache/ -type f -mtime +7 -delete"
end

every :day, at: "1:10" do
  command_in_path "find ./tmp/cache/ -type d -empty -delete -mindepth 1"
end