blob: b2d4e8a00c0784142572b8196e9ddae0fbdb26b1 [file] [log] [blame]
# Copyright 2016 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
"""Get time from the chameleon mirror server."""
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
import datetime
from chameleond.utils import system_tools
class ServerTimeException(Exception):
"""A dummpy exception class for the server_time module."""
class ServerTime(object):
"""Get the chameleon mirror server time.
This class provides a simple way to get time from the chameleon mirror server.
This class is required because of the rather limited date/time utilities
on a chameleon board.
Google servers provide time in GMT, i.e., UTC.
Note: this class does not take daylight saving time into consideration.
Should support it later if higher clock precision is needed.
MONTH = {'Jan': '01',
'Feb': '02',
'Mar': '03',
'Apr': '04',
'May': '05',
'Jun': '06',
'Jul': '07',
'Aug': '08',
'Sep': '09',
'Oct': '10',
'Nov': '11',
'Dec': '12'}
def get_timezone_offset(self):
"""Get the timezone offset with respect to UTC.
a timedelta object representing the timezone offset.
ServerTimeException if there is an error in executing the date command.
command = 'date +%z'.split()
# an offset looks like '+0800' or '-0700'
offset = system_tools.SystemTools.Output(*command).strip()
except Exception as e:
raise ServerTimeException('Failed to get timezone offset: %s.', e)
sign = -1 if offset[0] == '-' else 1
offset_hrs = sign * int(offset[1:3])
offset_mins = sign * int(offset[3:5])
return datetime.timedelta(hours=offset_hrs, minutes=offset_mins)
def chameleon_mirror_server_time(self):
"""Get current time from the chameleon mirror server.
Current time queried from CHAMELEON_MIRROR_URL looks like
Date: Thu, 07 Jul 2016 07:54:42 GMT
the datetime object representing current time like
datetime.datetime(2016, 7, 1, 15, 20, 50)
ServerTimeException if there is an error in getting the server time.
command = ('wget -S %s' % self.CHAMELEON_MIRROR_URL).split()
for line in system_tools.SystemTools.Output(*command).splitlines():
if 'Date' in line:
_, _, day, month, year, hrs_mins_secs, _ = line.split()
month = self.MONTH.get(month, '')
if month:
hrs, mins, secs = hrs_mins_secs.split(':')
return datetime.datetime(int(year), int(month), int(day),
int(hrs), int(mins), int(secs))
raise ServerTimeException('Failed to get chameleon mirror server time.')
def get(self):
"""Get current time.
the current time string in the timezone which the chameleon is currently
using. The time format looks like '2016-07-01 15:20:50'
curr_time = self.chameleon_mirror_server_time() + self.get_timezone_offset()
return curr_time.strftime('%Y-%m-%d %H:%M:%S')
if __name__ == '__main__':
# Print the chameleon mirror server time when running as a script.