Run commands when paths change.
You’ll need to install Node.js to use Watchy. Node comes packaged with npm, which is Node’s package manager, and the preferred method of installing Watchy. After installing Node, simply type
npm install -g watchy
and you should have the watchy
command available!
Usage: watchy [options] -- command arg1 arg2...
Options:
-h, --help output usage information
-V, --version output the version number
-w, --watch [paths] rerun the command when [paths] change
-i, --ignore [regex] [default /\.] ignore changes to paths matching [regex]
-k, --keep-alive restart on exit, useful for servers
-W, --wait [sec] time after SIGTERM to SIGKILL
-s, --silent be quieter, only output errors
-n, --no-color disable colored output
-S, --no-init-spawn prevent spawn when the watcher is created
-r, --restart [string] [default rs] enter this command to manually restart the process. Set to - to disable.
-p, --use-polling slower, but useful when watching over NFS
# The simple case
watchy -w lib -- say "The lib directory changed."
# Piping works as well
watchy -w styles -- bash -c "lessc styles/main.less | autoprefixer -o .tmp/styles/main.css"
# Keep a process alive, restarting it as soon as it exits or "server.js"
# changes.
watchy -kw server.js -- node server.js
# Watch every file except dotfiles, the node_modules folder, and JSON files.
# NOTE: Listen to as few files as possible for better performance.
watchy -w . -i '/\.|/node_modules|\.json$' -- node server.js
# Tick tock!
watchy -ks -- bash -c 'date && sleep 1'
# Tick tock (annoying version)!
watchy -ks -- bash -c 'say "In case you were wondering, it is `date`" && sleep 5'
# $EVENT and $FILE are passed to the process from chokidar (thanks @remy).
watchy -w . -- bash -c 'echo $EVENT $FILE'
# => change /Users/casey/projects/watchy/README.md
Note: If you’re using
watchy
for help with preprocessing, I’d recommend checking out my cogs project that is highly optimized for that case with in-memory processed file caching, directives, AMD support, and much more.
By default, watchy
will send SIGTERM
to the running process after a change and wait for it to exit gracefully. By sending the --wait|-W n
option, you can tell watchy
to forcefully SIGKILL
the process after n
seconds. In general, you should try to clean up connections in your processes like so:
process.on('SIGTERM', function () {
server.close();
db.disconnect();
redis.quit();
// etc...
});