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trigger commands on file change events


Build Status npm install

lightweight, flexible, file-watching command runner


npm install -g jung


so you can do jung -f '\.js$' -- browserify main.js -o bundle.js


jung *.md -- cat \$JUNG_FILE | marked -o \$JUNG_BARENAME.html


jung -r /var/log -- echo \$JUNG_FILE changed!

or any other variety of neat stuff.


jung [options] [files] -- <command>

Options are

  • --root, -r <dir> Watch files in <dir>, default cwd
  • --dirs, -d <regex> Only watch sub directories matching <regex>
  • --notdirs, -D <regex> Ignore sub directories matching <regex>
  • --files, -f <regex> Only watch files matching <regex>
  • --notfiles, -F <regex> Ignore files matching <regex>
  • --wait, -w <time> Debounce reaction for <time> ms, default 300
  • --timeout, -t <time> Wait <time> ms after SIGTERM to SIGKILL, default 500
  • --kill, -k Rather than queueing command runs, kill child process
  • --quiet, -q Do not show output from <command>
  • --run, -R Run <command> at first start
  • --version, -v Print jung version
  • --help, -h Print help

Commands are anything you can run in your shell. Including a shell script, for more complicated things!


When using jung as part of an npm run script, you will need to escape any \ in order to avoid JSON parsing errors.


  // ... 
  "scripts": {
    "watch-md": "jung -f '\\.md$' -- make html"
  // ... 

When your command is fired, the following environment variables will be available:

  • $JUNG_FILE - Full path to file that triggered the command
  • $JUNG_DIR - The directory the trigger file lives in
  • $JUNG_FILENAME - Just the filename part of the trigger file
  • $JUNG_EXTENSION - Just the extension of the trigger file
  • $JUNG_BARENAME - Trigger filename with no extension

If you run jung with --run these environment variables will be blank strings when the initial execution occurs.

This works really well with scripts, but for one-liners you will need to escape the $ to prevent your shell from replacing it too early.


jung -- echo $JUNG_FILE did something!


jung -- echo WHOA CHECKOUT \$JUNG_FILE || jung -- echo 'wee $JUNG_FILE'

as a module

var jung = require('jung')
var options = { files: ['\.js$', /\.md$/], quiet: true }
  , command = 'sh $JUNG_FILE'
jung(options, command).start()

module notes

Options accepts an object of options with keys matching the long form of any acceptable command line flag, for example files, notfiles, wait, etc.

files, notfiles, dirs, and notdirs each accept an array of either strings or RegExps or any combination thereof.

Any command line flags that do not accept an argument require a boolean value in the options object and they all default to false.

The second argument is the command which can be either a string of the command to be run or an array of each part of the command (i.e. command.split(' '))