Hack for django-compressor to recompile less files when imported less files (not referenced in html) are changed. See: https://github.com/django-compressor/django-compressor/issues/226

watchless.py

import time
from subprocess import call
from os.path import join
from django.conf import settings
from django.core.management.base import BaseCommand

from watchdog.observers import Observer
from watchdog.events import PatternMatchingEventHandler


MAIN_LESS_FILE = join(settings.STATICFILES_DIRS[0], 'css/styles.less')


class EventHandler(PatternMatchingEventHandler):
    def on_any_event(self, event):
        print '[%s] Touching styles.less' % int(time.time())
        call(['touch', MAIN_LESS_FILE])


class Command(BaseCommand):
    help = 'Touch main less file when any other less file is modified.'

    def handle(self, *args, **options):
        self.stdout.write('Watching less file changes...')

        event_handler = EventHandler(patterns=['*.less'], ignore_patterns=['*styles.less'], ignore_directories=True)
        observer = Observer()
        observer.schedule(event_handler, settings.DJANGO_ROOT, recursive=True)
        observer.start()

        try:
            while True:
                time.sleep(1)
        except KeyboardInterrupt:
            observer.stop()
        observer.join()