Simple utility for watching directory tree and file changes.

I could not find a single library that would do exactly what i was looking for, so here is yet another fs.watch wrapper.

This library detects changes in the directory tree and attaches/removes watches as necessary. It also aims to keep the number of watches low, while still noticing every file change.

npm install simple-treewatch

A very simple example for watching a single directory:

var watch = new(require('simple-treewatch'))();

watch.watch("/home/csaba");
watch.addAction(function(data) {
    console.log(data.event + " : " + data.fullPath);
});

The above example starts watching the directory tree, with the root being the path set in the parameter. It handles new subdirectories as well. You can add any number of actions to be exectued when an event occurs.

To see log messages coming from the watch handler, you can set the logging level to verbose. This prints messages such as watches being started or cancelled.

watch.setLogLevel('verbose');

You can also blacklist certain files via regexp. This regexp will be matched against the file or directory name.

watch.blacklist('^[.]');

In case you want to get a callback when a certain files is blacklisted, it can be done like this:

watch.blacklist('^[.]', function(filename) {
    console.log('Blacklisted event to hidden file/dir: ' + filename);
});

watch.blacklist('^~', function(filename) {
    console.log('Blacklisted event to swap file: ' + filename);
});

Removal of previously started (be it manual or automatic) watches is done automatically. To manually stop watching a given directory:

watch.cancelWatch('/home/csaba');