#!/usr/bin/env python
# pywws - Python software for USB Wireless Weather Stations
# http://github.com/jim-easterbrook/pywws
# Copyright (C) 2008-16 pywws contributors
# 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 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), :py:mod:`pywws.LogData` 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 :py:mod:`pywws.LogData` 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.
Detailed API
------------
"""
from __future__ import absolute_import
__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.constants import SECOND, HOUR
from pywws import DataStore
from pywws.Logger import ApplicationLogger
from pywws.WeatherStation import weather_station
[documentatie]class DataLogger(object):
def __init__(self, params, status, raw_data):
self.logger = logging.getLogger('pywws.DataLogger')
self.params = params
self.status = status
self.raw_data = raw_data
# connect to weather station
ws_type = self.params.get('fixed', 'ws type')
if ws_type:
self.params.unset('fixed', 'ws type')
self.params.set('config', 'ws type', ws_type)
ws_type = self.params.get('config', 'ws type', 'Unknown')
avoid = eval(self.params.get('config', 'usb activity margin', '3.0'))
self.ws = weather_station(
ws_type=ws_type, status=self.status, avoid=avoid)
# check for valid weather station type
fixed_block = self.check_fixed_block()
if 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)
# check computer clock isn't earlier than last stored data
last_stored = self.raw_data.before(datetime.max)
if last_stored and datetime.utcnow() < last_stored:
raise ValueError('Computer time is earlier than last stored data')
[documentatie] def check_fixed_block(self):
fixed_block = self.ws.get_fixed_block(unbuffered=True)
# check 'magic number'
if (fixed_block['magic_0'], fixed_block['magic_1']) not in (
(0x55, 0xAA),):
self.logger.critical("Unrecognised 'magic number' %02x %02x",
fixed_block['magic_0'], fixed_block['magic_1'])
# store info from fixed block
self.status.unset('fixed', 'pressure offset')
if not self.params.get('config', 'pressure offset'):
self.params.set('config', 'pressure offset', '%g' % (
fixed_block['rel_pressure'] - fixed_block['abs_pressure']))
self.params.unset('fixed', 'fixed block')
self.status.set('fixed', 'fixed block', str(fixed_block))
return fixed_block
[documentatie] def catchup(self, last_date, last_ptr):
fixed_block = self.ws.get_fixed_block(unbuffered=True)
# get time to go back to
last_stored = self.raw_data.before(datetime.max)
if not last_stored:
last_stored = datetime.min
if self.status.get('data', 'ptr'):
saved_ptr, saved_date = self.status.get('data', 'ptr').split(',')
saved_ptr = int(saved_ptr, 16)
saved_date = DataStore.safestrptime(saved_date)
saved_date = self.raw_data.nearest(saved_date)
while saved_date < last_stored:
saved_date = self.raw_data.after(saved_date + SECOND)
saved_ptr = self.ws.inc_ptr(saved_ptr)
else:
saved_ptr = None
saved_date = None
last_stored += timedelta(seconds=fixed_block['read_period'] * 30)
if last_date <= last_stored:
# nothing to do
return
self.status.set(
'data', 'ptr', '%06x,%s' % (last_ptr, last_date.isoformat(' ')))
# data_count includes record currently being updated every 48 seconds
max_count = fixed_block['data_count'] - 1
count = 0
duplicates = []
while last_date > last_stored and count < max_count:
data = self.ws.get_data(last_ptr)
if last_ptr == saved_ptr:
if any(data[key] != self.raw_data[saved_date][key] for key in (
'hum_in', 'temp_in', 'hum_out', 'temp_out',
'abs_pressure', 'wind_ave', 'wind_gust', 'wind_dir',
'rain', 'status')):
# pointer matches but data is different, so no duplicates
duplicates = None
saved_ptr = None
saved_date = None
else:
# potential duplicate data
duplicates.append(last_date)
saved_date = self.raw_data.before(saved_date)
saved_ptr = self.ws.dec_ptr(saved_ptr)
if (data['delay'] is None or
data['delay'] > max(fixed_block['read_period'] * 2, 35)):
self.logger.error('invalid data at %04x, %s',
last_ptr, last_date.isoformat(' '))
last_date -= timedelta(minutes=fixed_block['read_period'])
else:
self.raw_data[last_date] = data
count += 1
last_date -= timedelta(minutes=data['delay'])
last_ptr = self.ws.dec_ptr(last_ptr)
if duplicates:
for d in duplicates:
del self.raw_data[d]
count -= len(duplicates)
last_date = self.raw_data.nearest(last_date)
next_date = self.raw_data.after(last_date + SECOND)
if next_date:
gap = (next_date - last_date).seconds // 60
gap -= fixed_block['read_period']
if gap > 0:
self.logger.critical("%d minutes gap in data detected", gap)
self.logger.info("%d catchup records", count)
[documentatie] def log_data(self, sync=None, clear=False):
fixed_block = self.check_fixed_block()
# get sync config value
if sync is None:
if fixed_block['read_period'] <= 5:
sync = int(self.params.get('config', 'logdata sync', '1'))
else:
sync = int(self.params.get('config', 'logdata sync', '0'))
# get address and date-time of last complete logged data
self.logger.info('Synchronising to weather station')
range_hi = datetime.max
range_lo = datetime.min
last_delay = self.ws.get_data(self.ws.current_pos())['delay']
if last_delay == 0:
prev_date = datetime.min
else:
prev_date = datetime.utcnow()
for data, last_ptr, logged in self.ws.live_data(logged_only=(sync > 1)):
last_date = data['idx']
self.logger.debug('Reading time %s', last_date.strftime('%H:%M:%S'))
if logged:
break
if sync < 2 and self.ws._station_clock.clock:
err = last_date - datetime.fromtimestamp(
self.ws._station_clock.clock)
last_date -= timedelta(
minutes=data['delay'], seconds=err.seconds % 60)
self.logger.debug('log time %s', last_date.strftime('%H:%M:%S'))
last_ptr = self.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
self.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 = self.ws.dec_ptr(last_ptr)
break
# go back through stored data, until we catch up with what we've already got
self.logger.info('Fetching data')
self.catchup(last_date, last_ptr)
if clear:
self.logger.info('Clearing weather station memory')
ptr = self.ws.fixed_format['data_count'][0]
self.ws.write_data([(ptr, 1), (ptr+1, 0)])
[documentatie] def live_data(self, logged_only=False):
next_hour = datetime.utcnow(
).replace(minute=0, second=0, microsecond=0) + HOUR
next_ptr = None
for data, ptr, logged in self.ws.live_data(logged_only=logged_only):
if logged:
now = data['idx']
if ptr == next_ptr:
# data is contiguous with last logged value
self.raw_data[now] = data
if now >= next_hour:
next_hour += HOUR
self.check_fixed_block()
self.status.set(
'data', 'ptr', '%06x,%s' % (ptr, now.isoformat(' ')))
else:
# catch up missing data
self.catchup(now, ptr)
next_ptr = self.ws.inc_ptr(ptr)
yield data, logged
[documentatie]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]
DataLogger(
DataStore.params(root_dir), DataStore.status(root_dir),
DataStore.data_store(root_dir)).log_data(sync=sync, clear=clear)
if __name__ == "__main__":
sys.exit(main())