Watchy

Run commands when paths change.

Install

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

``bash
npm install -g watchy
`

and you should have the watchy command available!

Usage

`
Usage: watchy [options] -- [args...]

Run commands when paths change.

Options:
-V, --version output the version number
-d, --debounce [seconds] trigger a change at most every [seconds] seconds
-k, --keep-alive restart the process if it exits
-r, --restart [string] send [string] to STDIN to restart the process
-R, --no-restart-after-signal disable process restart after being signaled and exited
-s, --silent only output errors
-S, --no-init-spawn prevent spawn when the watcher is created
-t, --shutdown-signal [signal] use [signal] to shut down the process (default: "SIGTERM")
-T, --reload-signal [signal] use [signal] to reload the process (defaults to shutdown
signal)
-w, --watch [pattern] watch [pattern] for changes, can be specified multiple times
-W, --wait [seconds] send SIGKILL to the process after [seconds] if it hasn't
exited
-h, --help display help for command
`

The watch patterns are [extglob] format.

Examples

`bash


The simple case

watchy -w 'lib/*/' -- say "The lib directory changed."

Piping works as well

watchy -w 'styles/*/.less' -- 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'

The envvar WATCHY_PATHS is passed to the process.

watchy -S -w '*/' -- bash -c 'echo $WATCHY_PATHS changed'

=> modified /Users/casey/Documents/code/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.

SIGTERM

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:

`js
process.on('SIGTERM', () => {
server.close();
db.disconnect();
redis.quit();
// etc...
});
`

Node API

As of 0.9.0 watchy exposes a Node.js API.

`js
import { watch } from 'watchy';

watch({
debounce: 0.5,
onChange: paths => console.log(paths),
patterns: ['js//.js', 'css//.css'],
});
``

[cogs]: https://github.com/caseywebdev/cogs
[extglob]: https://www.linuxjournal.com/content/bash-extended-globbing
[Node.js]: https://nodejs.org
[npm]: https://www.npmjs.com