#!/usr/bin/env python
# pywws - Python software for USB Wireless Weather Stations
# http://github.com/jim-easterbrook/pywws
# Copyright (C) 2008-13 Jim Easterbrook jim@jim-easterbrook.me.uk
# 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 Street, Fifth Floor, Boston, MA 02110-1301, USA.
"""Save weather station history to file
::
%s
This program / module gets data from the weather station's memory and
stores it to file. Each time it is run it fetches all data that is
newer than the last stored data, so it only needs to be run every hour
or so. As the weather station typically stores two weeks' readings
(depending on the logging interval), LogData.py could be run quite
infrequently if you don't need up-to-date data.
There is no date or time information in the raw weather station data,
so LogData.py creates a time stamp for each reading. It uses the
computer's clock, rather than the weather station clock which can not
be read accurately by the computer. A networked computer should have
its clock set accurately by `ntp
<http://en.wikipedia.org/wiki/Network_Time_Protocol>`_.
Synchronisation with the weather station is achieved by waiting for a
change in the current data. There are two levels of synchronisation,
set by the config file or a command line option. Level 0 is quicker,
but is only accurate to around twelve seconds. Level 1 waits until the
weather station stores a new logged record, and gets time stamps
accurate to a couple of seconds. Note that this could take a long
time, if the logging interval is greater than the recommended five
minutes.
"""
__docformat__ = "restructuredtext en"
__usage__ = """
usage: python -m pywws.LogData [options] data_dir
options are:
-h | --help display this help
-c | --clear clear weather station's memory full indicator
-s n | --sync n set quality of synchronisation to weather station (0 or 1)
-v | --verbose increase number of informative messages
data_dir is the root directory of the weather data
"""
__doc__ %= __usage__
__usage__ = __doc__.split('\n')[0] + __usage__
from datetime import datetime, timedelta
import getopt
import logging
import os
import sys
import time
from pywws import DataStore
from pywws.Logger import ApplicationLogger
from pywws.TimeZone import Local
from pywws import WeatherStation
[docs]def Catchup(ws, logger, raw_data, last_date, last_ptr):
fixed_block = ws.get_fixed_block(unbuffered=True)
# get time to go back to
last_stored = raw_data.before(datetime.max)
if last_stored == None:
last_stored = datetime.min
if datetime.utcnow() < last_stored:
raise ValueError('Computer time is earlier than last stored data')
last_stored += timedelta(seconds=fixed_block['read_period'] * 30)
# data_count includes record currently being updated every 48 seconds
max_count = fixed_block['data_count'] - 1
count = 0
while last_date > last_stored and count < max_count:
data = ws.get_data(last_ptr)
if data['delay'] is None or data['delay'] > 30:
logger.error('invalid data at %04x, %s',
last_ptr, last_date.isoformat(' '))
last_date -= timedelta(minutes=fixed_block['read_period'])
else:
raw_data[last_date] = data
count += 1
last_date -= timedelta(minutes=data['delay'])
last_ptr = ws.dec_ptr(last_ptr)
if count > 0:
logger.info("%d catchup records", count)
[docs]def CheckFixedBlock(ws, params, status, logger):
fixed_block = ws.get_fixed_block(unbuffered=True)
# check clocks
try:
s_time = DataStore.safestrptime(
fixed_block['date_time'], '%Y-%m-%d %H:%M')
except Exception:
s_time = None
if s_time:
c_time = datetime.now().replace(second=0, microsecond=0)
diff = abs(s_time - c_time)
if diff > timedelta(minutes=2):
logger.warning(
"Computer and weather station clocks disagree by %s (H:M:S).", str(diff))
# store weather station type
params.set('config', 'ws type', ws.ws_type)
# store info from fixed block
pressure_offset = fixed_block['rel_pressure'] - fixed_block['abs_pressure']
old_offset = eval(status.get('fixed', 'pressure offset', 'None'))
if old_offset and abs(old_offset - pressure_offset) > 0.01:
# re-read fixed block, as can get incorrect values
logger.warning('Re-read fixed block')
fixed_block = ws.get_fixed_block(unbuffered=True)
if not fixed_block:
return None
pressure_offset = fixed_block['rel_pressure'] - fixed_block['abs_pressure']
if old_offset and abs(old_offset - pressure_offset) > 0.01:
logger.warning(
'Pressure offset change: %g -> %g', old_offset, pressure_offset)
params.unset('fixed', 'pressure offset')
params.unset('fixed', 'fixed block')
status.set('fixed', 'pressure offset', '%g' % (pressure_offset))
status.set('fixed', 'fixed block', str(fixed_block))
return fixed_block
[docs]def LogData(params, status, raw_data, sync=None, clear=False):
logger = logging.getLogger('pywws.LogData')
# connect to weather station
ws_type = params.get('fixed', 'ws type')
if ws_type:
params.unset('fixed', 'ws type')
params.set('config', 'ws type', ws_type)
ws_type = params.get('config', 'ws type', 'Unknown')
ws = WeatherStation.weather_station(
ws_type=ws_type, params=params, status=status)
fixed_block = CheckFixedBlock(ws, params, status, logger)
# check for valid weather station type
if ws.ws_type not in ('1080', '3080'):
print "Unknown weather station type. Please edit weather.ini"
print "and set 'ws type' to '1080' or '3080', as appropriate."
if fixed_block['lux_wm2_coeff'] == 0.0:
print "Your station is probably a '1080' type."
else:
print "Your station is probably a '3080' type."
sys.exit(1)
# get sync config value
if sync is None:
if fixed_block['read_period'] <= 5:
sync = int(params.get('config', 'logdata sync', '1'))
else:
sync = int(params.get('config', 'logdata sync', '0'))
# get address and date-time of last complete logged data
logger.info('Synchronising to weather station')
range_hi = datetime.max
range_lo = datetime.min
last_delay = ws.get_data(ws.current_pos())['delay']
if last_delay == 0:
prev_date = datetime.min
else:
prev_date = datetime.utcnow()
for data, last_ptr, logged in ws.live_data(logged_only=(sync > 1)):
last_date = data['idx']
logger.debug('Reading time %s', last_date.strftime('%H:%M:%S'))
if logged:
break
if sync < 2 and ws._station_clock:
err = last_date - datetime.fromtimestamp(ws._station_clock)
last_date -= timedelta(
minutes=data['delay'], seconds=err.seconds % 60)
logger.debug('log time %s', last_date.strftime('%H:%M:%S'))
last_ptr = ws.dec_ptr(last_ptr)
break
if sync < 1:
hi = last_date - timedelta(minutes=data['delay'])
if last_date - prev_date > timedelta(seconds=50):
lo = hi - timedelta(seconds=60)
elif data['delay'] == last_delay:
lo = hi - timedelta(seconds=60)
hi = hi - timedelta(seconds=48)
else:
lo = hi - timedelta(seconds=48)
last_delay = data['delay']
prev_date = last_date
range_hi = min(range_hi, hi)
range_lo = max(range_lo, lo)
err = (range_hi - range_lo) / 2
last_date = range_lo + err
logger.debug('est log time %s +- %ds (%s..%s)',
last_date.strftime('%H:%M:%S'), err.seconds,
lo.strftime('%H:%M:%S'), hi.strftime('%H:%M:%S'))
if err < timedelta(seconds=15):
last_ptr = ws.dec_ptr(last_ptr)
break
# go back through stored data, until we catch up with what we've already got
logger.info('Fetching data')
Catchup(ws, logger, raw_data, last_date, last_ptr)
if clear:
logger.info('Clearing weather station memory')
ptr = ws.fixed_format['data_count'][0]
ws.write_data([(ptr, 1), (ptr+1, 0)])
[docs]def main(argv=None):
if argv is None:
argv = sys.argv
try:
opts, args = getopt.getopt(
argv[1:], "hcs:v", ('help', 'clear', 'sync=', 'verbose'))
except getopt.error, msg:
print >>sys.stderr, 'Error: %s\n' % msg
print >>sys.stderr, __usage__.strip()
return 1
# process options
clear = False
sync = None
verbose = 0
for o, a in opts:
if o in ('-h', '--help'):
print __usage__.strip()
return 0
elif o in ('-c', '--clear'):
clear = True
elif o in ('-s', '--sync'):
sync = int(a)
elif o in ('-v', '--verbose'):
verbose += 1
# check arguments
if len(args) != 1:
print >>sys.stderr, 'Error: 1 argument required\n'
print >>sys.stderr, __usage__.strip()
return 2
logger = ApplicationLogger(verbose)
root_dir = args[0]
return LogData(
DataStore.params(root_dir), DataStore.status(root_dir),
DataStore.data_store(root_dir), sync=sync, clear=clear)
if __name__ == "__main__":
sys.exit(main())