backports: Add buster-backports to apt sources list

Fixes freedombox-team/freedom-maker#149

Signed-off-by: Joseph Nuthalapati <njoseph@thoughtworks.com>
Reviewed-by: Sunil Mohan Adapa <sunil@medhas.org>

actions/backports

@@ -0,0 +1,116 @@
+#!/usr/bin/python3
+# -*- mode: python -*-
+#
+# This file is part of FreedomBox.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero 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 Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+"""
+Script to check for availability of buster-backports and create an
+apt sources list for backports if available.
+"""
+
+import argparse
+import os
+import requests
+
+from plinth import action_utils
+
+BUSTER_BACKPORTS_RELEASE_FILE_URL = "http://cdn-fastly.deb.debian.org/debian/dists/buster-backports/Release"
+
+
+def parse_arguments():
+    """Return parsed command line arguments as dictionary."""
+    parser = argparse.ArgumentParser()
+    subparsers = parser.add_subparsers(dest='subcommand', help='Sub command')
+
+    subparsers.add_parser('enable', help='Enable buster backports check')
+    subparsers.add_parser('disable', help='Disable buster backports check')
+    subparsers.add_parser('check-backports',
+                          help='Check whether buster backports are available')
+
+    subparsers.required = True
+    return parser.parse_args()
+
+
+def add_buster_backports_sources():
+    backports_list = '/etc/apt/sources.list.d/freedombox-backports.list'
+
+    conf = \
+"""deb http://deb.debian.org/debian buster-backports main
+deb-src http://deb.debian.org/debian buster-backports main
+"""
+
+    components = {"main"}
+
+    # Use tor+http if download over tor is enabled in sources.list
+    with open('/etc/apt/sources.list', 'r') as sources_list:
+        sources = sources_list.readlines()
+        for line in sources:
+            if not line.startswith("#") and "tor+http" in line:
+                conf = conf.replace("http", "tor+http")
+                # Check for contrib and nonfree components
+                if "contrib" in line:
+                    components.add("contrib")
+                if "nonfree" in line:
+                    components.add("nonfree")
+                break
+
+    conf = conf.replace("main", " ".join(components))
+
+    if not os.path.exists(backports_list):
+        try:
+            with open(backports_list, 'w') as file_handle:
+                file_handle.write(conf)
+        except PermissionError:
+            print(("Failed adding sources list for buster-backports."
+                   "Try running as a superuser."))
+
+
+def subcommand_check_backports(_):
+    """Check whether buster backports is available.
+    Add a sources file if it's available.
+    """
+    response = requests.get(BUSTER_BACKPORTS_RELEASE_FILE_URL)
+
+    if response.status_code == 404:
+        print("Release file for Buster backports is not available yet.")
+    else:
+        print("Buster backports is now available. Adding to sources...")
+        add_buster_backports_sources()
+
+
+def subcommand_enable(_):
+    """Enable systemd service for the daily job buster-backports-check."""
+    action_utils.service_enable('buster-backports-check.timer')
+    action_utils.service_start('buster-backports-check.timer')
+
+
+def subcommand_disable(_):
+    """Disable systemd service for the daily job buster-backports-check."""
+    action_utils.service_stop('buster-backports-check.timer')
+    action_utils.service_disable('buster-backports-check.timer')
+
+
+def main():
+    """Parse arguments and perform all duties."""
+    arguments = parse_arguments()
+
+    subcommand = arguments.subcommand.replace('-', '_')
+    subcommand_method = globals()['subcommand_' + subcommand]
+    subcommand_method(arguments)
+
+
+if __name__ == '__main__':
+    main()

data/etc/apt/preferences.d/freedombox.pref

@@ -0,0 +1,3 @@
+Package: freedombox
+Pin: release a=buster-backports
+Pin-Priority: 800

data/etc/plinth/modules-enabled/backports

@@ -0,0 +1,2 @@
+plinth.modules.backports
+

data/lib/systemd/system/buster-backports-check.service

@@ -0,0 +1,24 @@
+#
+# This file is part of FreedomBox.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero 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 Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+[Unit]
+Description=Service to check for buster backports and enable them
+ConditionPathExists=!/etc/apt/sources.list.d/freedombox-backports.list
+
+[Service]
+ExecStart=/usr/share/plinth/actions/backports check-backports
+

data/lib/systemd/system/buster-backports-check.timer

@@ -0,0 +1,27 @@
+#
+# This file is part of FreedomBox.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero 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 Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+[Unit]
+Description=Daily check of whether buster backports are available yet
+
+[Timer]
+OnCalendar=daily
+AccuracySec=12h
+Persistent=true
+
+[Install]
+WantedBy=multi-user.target

debian/postrm

@@ -9,6 +9,10 @@ purge)
 
 	# Remove legacy directory too
 	rm -rf /var/log/plinth
+
+  if [ -e '/etc/apt/sources.list.d/freedombox-backports.list' ]; then
+      rm /etc/apt/sources.list.d/freedombox-backports.list
+  fi
 	;;
 esac
 

plinth/modules/backports/__init__.py

@@ -0,0 +1,30 @@
+#
+# This file is part of FreedomBox.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero 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 Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+"""
+FreedomBox app to manage Debian backports.
+"""
+
+from plinth import actions
+
+is_essential = True
+
+version = 1
+
+
+def setup(helper, old_version=None):
+    """Configure the module."""
+    helper.call('post', actions.superuser_run, 'backports', ['enable'])

plinth/modules/backports/urls.py

@@ -0,0 +1,21 @@
+#
+# This file is part of FreedomBox.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero 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 Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+"""
+URLs for the Backports module.
+"""
+
+urlpatterns = []

plinth/package.py

@@ -84,7 +84,7 @@ class Transaction(object):
                     self.package_names)
             else:
                 self._run_apt_command(['install', self.module_name] +
-                                  self.package_names)
+                                      self.package_names)
         except subprocess.CalledProcessError as exception:
             logger.exception('Error installing package: %s', exception)
             raise

setup.py

@@ -238,6 +238,8 @@ setuptools.setup(
          glob.glob('data/etc/apache2/includes/*.conf')),
         ('/etc/apt/apt.conf.d',
          glob.glob('data/etc/apt/apt.conf.d/60unattended-upgrades')),
+        ('/etc/apt/preferences.d',
+         glob.glob('data/etc/apt/preferences.d/freedombox.pref')),
         ('/etc/avahi/services/',
          glob.glob('data/etc/avahi/services/*.service')),
         ('/etc/ikiwiki', glob.glob('data/etc/ikiwiki/*.setup')),
@@ -247,6 +249,7 @@ setuptools.setup(
             'data/etc/sudoers.d/plinth'
         ]), ('/lib/systemd/system',
              glob.glob('data/lib/systemd/system/*.service')),
+        ('/lib/systemd/system', glob.glob('data/lib/systemd/system/*.timer')),
         ('/etc/mediawiki',
          glob.glob('data/etc/mediawiki/*.php')), ('/etc/update-motd.d/', [
              'data/etc/update-motd.d/50-freedombox'