Use incrontab to auto-update vagrant boxes

refresh_vagrant_box.py

#!/usr/bin/env python3

# Run by incron whenever a file in the vagrant_boxes dir changes.
# Updates the corresponding box in vagrant (vagrant box add -f)
#
# For me, boxes in vagrant_boxes are created on another machine
# and synced over with BTSync.  This detects the change for me and
# makes sure my local box is fresh.
#
# Add this to your incrontab:
# /path/to/vagrant_boxes IN_CREATE,IN_CLOSE_WRITE,IN_MOVE,IN_NO_LOOP /path/to/refresh_vagrant_box.py $@/$# $%

import sys
import os
import sh
import logging

logfile = os.path.expanduser('~/incron.log')

boxes_to_monitor = [
    'windows_81_virtualbox.box',
    'windows_2012_r2_virtualbox.box',
]

logger = logging.getLogger('refresh_vagrant_box')
logger.setLevel(logging.DEBUG)
fh = logging.FileHandler(logfile)
fh.setLevel(logging.DEBUG)
logger.addHandler(fh)

file_path = sys.argv[1]
event_flags = sys.argv[2]

# somehow BTSync avoids triggering any write/move on the final filename.
# So, we'll just wait for the end of writing and then process the output file.
if file_path.endswith('.!sync') and event_flags == 'IN_CLOSE_WRITE':
    file_path = os.path.splitext(file_path)[0]

file_base = os.path.basename(file_path)
if file_base in boxes_to_monitor:
    # windows_2012_r2_virtualbox.box -> windows_2012_r2
    box_name = file_base.rsplit('_', 1)[0]

    if os.path.exists(file_path):
        logger.debug('Updating {} {}'.format(box_name, event_flags))
        sh.vagrant('box', 'add', '-f', box_name, file_path)
    else:
        logger.debug('File not found - skipping')
else:
    logger.debug('Skipping {} {}'.format(file_path, event_flags))