sugar-network-thumber

#!/usr/bin/env python

# Copyright (C) 2014 Aleksey Lim
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

import os
from os.path import exists, join

from sugar_network.toolkit import coroutine
coroutine.inject()

from sugar_network import toolkit
from sugar_network.node import model
from sugar_network.node.slave import SlaveRoutes
from sugar_network.toolkit import application, i18n, Option, enforce


data_root = Option(
        'path to a directory to place node data',
        default='/var/lib/sugar-network', name='data_root')

force = Option(
        'intensify regular behaviour',
        default=False, type_cast=Option.bool_cast, short_option='-f',
        action='store_true', name='force')


class Application(application.Daemon):

    seqno = None
    volume = None
    jobs = coroutine.Pool()

    def prolog(self):
        if not exists(data_root.value):
            os.makedirs(data_root.value)
        enforce(os.access(data_root.value, os.W_OK),
                'No write access to %r directory', data_root.value)
        for opt, dirname in [
                (application.logdir, 'log'),
                (application.rundir, 'run'),
                ]:
            if not opt.value:
                opt.value = join(data_root.value, dirname)
            if not exists(opt.value):
                os.makedirs(opt.value)

        self.seqno = toolkit.Bin(
                join(data_root.value, 'var', 'seqno-thumbs'), 1)
        self.volume = model.Volume(data_root.value, SlaveRoutes.RESOURCES)

    def run(self):
        self.jobs.spawn(self.volume.blobs.poll_thumbs)
        self.jobs.spawn(self.volume.blobs.populate_thumbs, self.seqno.value)
        self.accept()
        try:
            self.jobs.join()
        finally:
            self.seqno.value = self.volume.seqno.value
            self.seqno.commit()

    def shutdown(self):
        self.jobs.kill()

    @application.command(
            'generate missed thumbnails; if --force is specified, '
            'all thumbnails will be re-generated', name='thumb')
    def thumb(self):
        self.volume.blobs.populate_thumbs(
                seqno=None if force.value else self.seqno.value,
                force=force.value)
        self.seqno.value = self.volume.seqno.value
        self.seqno.commit()


i18n.init('sugar-network')

# New defaults
application.logdir.value = None
application.rundir.value = None

Option.seek('main', application)
Option.seek('main', [force])
Option.seek('node', [data_root])

app = Application(
        name='sugar-network-thumber',
        description='Generate thumbnails on demand on Sugar Network node side',
        epilog='See http://wiki.sugarlabs.org/go/Sugar_Network '
               'for details.',
        config_files=[
            '/etc/sugar-network.d',
            '/etc/sugar-network.conf',
            '~/.config/sugar-network/config',
            ])
app.start()