Code source de pywws.Template

#!/usr/bin/env python
# -*- coding: utf-8 -*-

# pywws - Python software for USB Wireless Weather Stations
# Copyright (C) 2008-13  Jim Easterbrook

# 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
# 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.

"""Create text data file based on a template



This is probably the most difficult to use module in the weather
station software collection. It generates text files based on a
"template" file plus the raw, hourly, daily & monthly weather station
data. The template processing goes beyond simple substitution of
values to include loops, jumps forwards or backwards in the data,
processing of the data and substitution of missing values.

A template file can be any sort of text file (plain text, xml, html,
etc.) to which "processing instructions" have been added. These
processing instructions are delimited by hash ('#') characters. They
are not copied to the output, but cause something else to happen:
either a data value is inserted or one of a limited number of other
actions is carried out.

Before writing your own template files, it might be useful to look at
some of the examples in the example_templates directory.

Processing instructions


output a single '#' character.

``#! comment text#``

a comment, no output generated. ``comment text`` can be any text
without a line break.


switch to "monthly" summary data. The index is reset to the most
recent value.


switch to "daily" summary data. The index is reset to the most recent


switch to "hourly" summary data. The index is reset to the most recent


switch to "raw" data. The index is reset to the most recent value.

``#timezone name#``

convert all datetime values to time zone ``name`` before output.
Permitted values for name are ``utc`` or ``local``.

``#roundtime expr#``

switch time rounding on or off, according to ``expr``. When time
rounding is on, 30 seconds is added to each time value used. This is
useful if you are only printing out hours and minutes, e.g. with a
"%%H:%%M" format, and want time values such as 10:23:58 to appear as
"10:24". Use ``"True"`` or ``"False"`` for expr.

``#jump count#``

jump ``count`` values. The data index is adjusted by ``count`` hours
or days. Negative values jump back in time.

It is a good idea to put jumps within a loop at the end, just before
the ``#endloop#`` instruction. The loop can then terminate cleanly if
it has run out of data.

``#goto date-time#``

go to ``date-time``. The data index is adjusted to the record
immediately after ``date-time``. This can be in UTC or your local time
zone, according to the setting of ``timezone``, and must exactly match
the ISO date format, for example ``"2010-11-01 12:00:00"`` is noon on
1st November 2010.

Parts of ``date-time`` can be replaced with strftime style %% format
characters to specify the current loop index. For example,
``"%%Y-%%m-01 12:00:00"`` is noon on 1st of this month.

``#loop count#``

start a loop that will repeat ``count`` times. ``count`` must be one
or more.


end a loop started by ``#loop count#``. The template processing will
go back to the line containing the ``#loop count#`` instruction. Don't
try to nest loops.

``#key fmt_string no_value_string conversion#``

output a data value. ``key`` is the data key, e.g. ``temp_out`` for
outdoor temperature. ``fmt_string`` is a printf-like format string
(actually Python's %% operator) except for datetime values, when it is
input to datetime's ``strftime()`` method. ``no_value_string`` is
output instead of ``fmt_string`` when the data value is absent, e.g.
if the station lost contact with the outside sensor. ``conversion`` is
a Python expression to convert the data, e.g. to convert wind speed
from m/s to mph you could use ``"x * 3.6 / 1.609344"``, or the more
convenient provided function ``"wind_mph(x)"``.

All these values need double quotes " if they contain spaces or other
potentially difficult characters. All except ``key`` are optional, but
note that if you want to specify a conversion, you also need to
specify ``fmt_string`` and ``no_value_string``.

``#calc expression fmt_string no_value_string conversion#``

output a value computed from one or more data items. ``expression`` is
any valid Python expression, e.g. ``"dew_point(data['temp_out'],
data['hum_out'])"`` to compute the outdoor dew point. ``fmt_string``,
``no_value_string`` and ``conversion`` are as described above. Note
that it is probably more efficient to incorporate any conversion into


Here is an example snippet showing basic and advanced use of the
template features. It is part of the 6hrs.txt example template file,
which generates an HTML table of 7 hourly readings (which should span
6 hours). ::

  #jump -6#
  #loop 7#
      <td>#idx "%%Y/%%m/%%d" "" "[None, x][x.hour == 0 or loop_count == 7]"#</td>
      <td>#idx "%%H%%M %%Z"#</td>
      <td>#temp_out "%%.1f °C"#</td>
      <td>#hum_out "%%d%%%%"#</td>
      <td>#wind_dir "%%s" "-" "winddir_text(x)"#</td>
      <td>#wind_ave "%%.0f mph" "" "wind_mph(x)"#</td>
      <td>#wind_gust "%%.0f mph" "" "wind_mph(x)"#</td>
      <td>#rain "%%0.1f mm"#</td>
      <td>#rel_pressure "%%.0f hPa"#, #pressure_trend "%%s" "" "pressure_trend_text(x)"#</td>
  #jump 1#

The first three lines of this snippet do the following: select hourly
data, jump back 6 hours, start a loop with a count of 7. A jump
forward of one hour appears just before the end of the repeated
segment. As this last jump (of one hour) happens each time round the
loop, a sequence of 7 data readings will be output. The last line
marks the end of the loop — everything between the ``#loop 7#`` and
``#endloop#`` lines is output 7 times.

The ``#temp_out ...#``, ``#hum_out ...#``, ``#rain ...#`` and
``#rel_pressure ...#`` instructions show basic data output. They each
use a ``fmt_string`` to format the data appropriately. The ``#wind_ave
...#`` and ``#wind_gust ...#`` instructions show how to use a
conversion expression to convert m/s to mph.

The ``#wind_dir ...#`` and ``#pressure_trend ...#`` instructions show
use of the built-in functions ``winddir_text`` and
``pressure_trend_text`` to convert numerical values into text.

Finally we get to datetime values. The ``#idx "%%H%%M"#`` instruction
simply outputs the time (in HHMM format) of the data's index. The
``#idx "%%Y/%%m/%%d" "" "[None, x][x.hour == 0 or loop_count == 7]"#``
instruction is a bit more complicated. It outputs the date, but only
on the first line or if the date has changed. It does this by indexing
the array ``[None, x]`` with a boolean expression that is true when
``loop_count`` is 7 (i.e. on the first pass through the loop) or
``x.hour`` is zero (i.e. this is the first hour of the day).

Detailed API


__docformat__ = "restructuredtext en"
__usage__ = """
 usage: python -m pywws.Template [options] data_dir template_file output_file
 options are:
  --help    display this help
 data_dir is the root directory of the weather data
 template_file is the template text source file
 output_file is the name of the text file to be created
__doc__ %= __usage__
__usage__ = __doc__.split('\n')[0] + __usage__

import codecs
from datetime import datetime, timedelta
import getopt
import locale
import logging
import os
import shlex
import sys

from pywws import conversions
from conversions import *
from pywws import DataStore
from pywws.Forecast import Zambretti, ZambrettiCode
from pywws import Localisation
from pywws.Logger import ApplicationLogger
from pywws.TimeZone import Local, utc

SECOND = timedelta(seconds=1)
HOUR = timedelta(hours=1)
DAY = timedelta(hours=24)

[docs]class Template(object): def __init__(self, params, status, calib_data, hourly_data, daily_data, monthly_data, use_locale=True): self.logger = logging.getLogger('pywws.Template') self.params = params self.status = status self.calib_data = calib_data self.hourly_data = hourly_data self.daily_data = daily_data self.monthly_data = monthly_data self.use_locale = use_locale self.midnight = None self.rain_midnight = None # get character encoding of template input & output self.encoding = params.get('config', 'template encoding', 'iso-8859-1')
[docs] def process(self, live_data, template_file): def jump(idx, count): while count > 0: new_idx = data_set.after(idx + SECOND) if new_idx == None: break idx = new_idx count -= 1 while count < 0: new_idx = data_set.before(idx) if new_idx == None: break idx = new_idx count += 1 return idx, count == 0 params = self.params if not live_data: idx = self.calib_data.before(datetime.max) if not idx: self.logger.error("No calib data - run first") return live_data = self.calib_data[idx] # get conversions module to create its 'private' wind dir text # array, then copy it to deprecated wind_dir_text variable winddir_text(0) wind_dir_text = conversions._winddir_text_array hour_diff = self._hour_diff rain_hour = self._rain_hour rain_day = self._rain_day pressure_offset = eval(self.status.get('fixed', 'pressure offset')) fixed_block = eval(self.status.get('fixed', 'fixed block')) # start off with no time rounding round_time = None # start off in hourly data mode data_set = self.hourly_data # start off in utc time_zone = utc # jump to last item idx, valid_data = jump(datetime.max, -1) if not valid_data: self.logger.error("No summary data - run first") return data = data_set[idx] # open template file file if sys.version_info[0] >= 3: tmplt = open(template_file, 'r', encoding=self.encoding) else: tmplt = open(template_file, 'r') # do the text processing while True: line = tmplt.readline() if line == '': break parts = line.split('#') for i in range(len(parts)): if i % 2 == 0: # not a processing directive if i == 0 or parts[i] != '\n': yield parts[i] continue if parts[i] and parts[i][0] == '!': # comment continue command = shlex.split(parts[i]) if command == []: # empty command == print a single '#' yield '#' elif command[0] in data.keys() + ['calc']: # output a value if not valid_data: continue # format is: key fmt_string no_value_string conversion # get value if command[0] == 'calc': x = eval(command[1]) del command[1] else: x = data[command[0]] # adjust time if isinstance(x, datetime): if round_time: x += round_time x = x.replace(tzinfo=utc) x = x.astimezone(time_zone) # convert data if x != None and len(command) > 3: x = eval(command[3]) # get format fmt = '%s' if len(command) > 1: fmt = command[1] # write output if x == None: if len(command) > 2: yield command[2] elif isinstance(x, datetime): yield x.strftime(fmt) elif not self.use_locale: yield fmt % (x) elif sys.version_info >= (2, 7) or '%%' not in fmt: yield locale.format_string(fmt, x) else: yield locale.format_string( fmt.replace('%%', '##'), x).replace('##', '%') elif command[0] == 'monthly': data_set = self.monthly_data idx, valid_data = jump(datetime.max, -1) data = data_set[idx] elif command[0] == 'daily': data_set = self.daily_data idx, valid_data = jump(datetime.max, -1) data = data_set[idx] elif command[0] == 'hourly': data_set = self.hourly_data idx, valid_data = jump(datetime.max, -1) data = data_set[idx] elif command[0] == 'raw': data_set = self.calib_data idx, valid_data = jump(datetime.max, -1) data = data_set[idx] elif command[0] == 'live': data_set = self.calib_data idx = datetime.max valid_data = True data = live_data elif command[0] == 'timezone': if command[1] == 'utc': time_zone = utc elif command[1] == 'local': time_zone = Local else: self.logger.error("Unknown time zone: %s", command[1]) return elif command[0] == 'roundtime': if eval(command[1]): round_time = timedelta(seconds=30) else: round_time = None elif command[0] == 'jump': prevdata = data idx, valid_data = jump(idx, int(command[1])) data = data_set[idx] elif command[0] == 'goto': prevdata = data time_str = command[1] if '%' in time_str: lcl = idx.replace(tzinfo=utc).astimezone(time_zone) time_str = lcl.strftime(time_str) new_idx = DataStore.safestrptime(time_str) new_idx = new_idx.replace(tzinfo=time_zone).astimezone(utc) new_idx = data_set.after(new_idx.replace(tzinfo=None)) if new_idx: idx = new_idx data = data_set[idx] valid_data = True else: valid_data = False elif command[0] == 'loop': loop_count = int(command[1]) loop_start = tmplt.tell() elif command[0] == 'endloop': loop_count -= 1 if valid_data and loop_count > 0:, 0) else: self.logger.error( "Unknown processing directive: #%s#", parts[i]) return tmplt.close() return
[docs] def make_text(self, template_file, live_data=None): result = '' for text in self.process(live_data, template_file): if sys.version_info[0] < 3 and isinstance(text, unicode): text = text.encode(self.encoding) result += text return result
[docs] def make_file(self, template_file, output_file, live_data=None): if sys.version_info[0] >= 3: of = open(output_file, 'w', encoding=self.encoding) else: of = open(output_file, 'w') for text in self.process(live_data, template_file): if sys.version_info[0] < 3 and isinstance(text, unicode): text = text.encode(self.encoding) of.write(text) of.close() return 0
def _hour_diff(self, data, key): hour_ago = self.calib_data[self.calib_data.nearest(data['idx'] - HOUR)] return data[key] - hour_ago[key] def _rain_hour(self, data): rain_hour = self.calib_data[self.calib_data.nearest(data['idx'] - HOUR)]['rain'] return max(0.0, data['rain'] - rain_hour) def _rain_day(self, data): if not self.midnight: self.midnight = datetime.utcnow().replace(tzinfo=utc).astimezone( Local).replace(hour=0, minute=0, second=0).astimezone( utc).replace(tzinfo=None) while data['idx'] < self.midnight: self.midnight -= DAY self.rain_midnight = None while data['idx'] >= self.midnight + DAY: self.midnight += DAY self.rain_midnight = None if self.rain_midnight is None: self.rain_midnight = self.calib_data[ self.calib_data.nearest(self.midnight)]['rain'] return max(0.0, data['rain'] - self.rain_midnight)
[docs]def main(argv=None): if argv is None: argv = sys.argv try: opts, args = getopt.getopt(argv[1:], "", ['help']) except getopt.error, msg: print >>sys.stderr, 'Error: %s\n' % msg print >>sys.stderr, __usage__.strip() return 1 # check arguments if len(args) != 3: print >>sys.stderr, 'Error: 3 arguments required\n' print >>sys.stderr, __usage__.strip() return 2 # process options for o, a in opts: if o == '--help': print __usage__.strip() return 0 logger = ApplicationLogger(1) params = DataStore.params(args[0]) status = DataStore.status(args[0]) Localisation.SetApplicationLanguage(params) return Template( params, status, DataStore.calib_store(args[0]), DataStore.hourly_store(args[0]), DataStore.daily_store(args[0]), DataStore.monthly_store(args[0]) ).make_file(args[1], args[2])
if __name__ == "__main__": sys.exit(main())