[Dextrose] [PATCH][Dx2][dx-platform] Lease expiration reminder

[Martin Abente]

Emit a signal to remind users about the
procedure required to re-activate their laptop
at school.

The signal will fire a notification once each day, 
_DAYS_UNTIL_WARNING days prior to the lease 
expiration date.

Implements #2658

---
 etc/cron.daily/remind |   66 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 66 insertions(+), 0 deletions(-)
 create mode 100644 etc/cron.daily/remind

diff --git a/etc/cron.daily/remind b/etc/cron.daily/remind
new file mode 100644
index 0000000..0bed88a
--- /dev/null
+++ b/etc/cron.daily/remind
@@ -0,0 +1,66 @@
+#!/usr/bin/env python
+# Copyright (C) 2011, Martin Abente
+#
+# 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 2 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, write to the Free Software
+# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+import os
+import sys
+import dbus
+import dbus.service
+from datetime import datetime
+
+_DBUS_SYSTEM_IFACE = 'org.sugarlabs.system'
+_DBUS_SYSTEM_PATH = '/org/sugarlabs/system'
+_DBUS_SYSTEM_NAME = 'Remind'
+_XO_1_0_LEASE_PATH = '/security/lease.sig'
+_XO_1_5_LEASE_PATH = '/bootpart/boot/security/lease.sig'
+_DATE_FORMAT = '%Y%m%dT%H%M%SZ'
+_DAYS_UNTIL_WARNING = 2
+
+def _emit_reminder_signal():
+    signal = dbus.lowlevel.SignalMessage(_DBUS_SYSTEM_PATH,
+                                        _DBUS_SYSTEM_IFACE,
+                                        _DBUS_SYSTEM_NAME)
+    sys = dbus.SystemBus()
+    sys.send_message(signal)
+
+def _get_lease_path():
+    if os.path.exists(_XO_1_0_LEASE_PATH):
+        return _XO_1_0_LEASE_PATH
+    elif os.path.exists(_XO_1_5_LEASE_PATH):
+        return _XO_1_5_LEASE_PATH
+    else:
+        print 'Can\'t find lease file'
+        sys.exit(-1)
+
+def _get_remaining_days():
+    lease_path = _get_lease_path()
+
+    with open(lease_path) as lease_file:
+        lease_data = lease_file.read()
+
+    encoded_date = lease_data.split()[3]
+    expiration_date = datetime.strptime(encoded_date, _DATE_FORMAT)
+    current_date = datetime.today()
+    delta_date = abs(expiration_date - current_date)
+    return delta_date.days
+
+def check_expiration_date():
+    remaining_days = _get_remaining_days()
+    if remaining_days <= _DAYS_UNTIL_WARNING:
+        _emit_reminder_signal()
+
+
+check_expiration_date()
-- 
1.7.4.4