contrib/statusd/statusd_weather.lua

   1 -- Authors: Andrea Rossato <arossato@istitutocolli.org>, Sergey Kozhemyakin <luc@server.by>
   2 -- License: GPL, version 2 or later
   3 -- Last Changed: 2008
   4 --
   5 -- statusd_weather.lua
   6
   7 -- statusd_weather.lua: an Ion3 statusd applet for displaying weather information
   8 -- based on weather.lua by Andrea Rossato arossato AT istitutocolli DOT org
   9
  10 -- Here's the list of all available data:
  11 -- %weather_location
  12 -- %weather_country
  13 -- %weather_date
  14 -- %weather_time (UTC)
  15 -- %weather_timestamp  (timestamp of the latest report: your local time.)
  16 -- %weather_tempF (Fahrenheit)
  17 -- %weather_tempC (Celsius)
  18 -- %weather_dewpointF (Fahrenheit)
  19 -- %weather_dewpointC (Celsius)
  20 -- %weather_humidity
  21 -- %weather_pressure (hPa)
  22 -- %weather_wind
  23 -- %weather_windspeed (MPH)
  24 -- %weather_windchillF (Fahrenheit)
  25 -- %weather_windchillC (Celsius)
  26 -- %weather_sky
  27 -- %weather_weather
  28
  29 -- LEGAL
  30 -- Copyright (C) 2006  Andrea Rossato arossato AT istitutocolli DOT org
  31 -- Copyright (C) 2008  Sergey Kozhemyakin luc AT server DOT by
  32
  33 -- This program is free software; you can redistribute it and/or
  34 -- modify it under the terms of the GNU General Public License
  35 -- as published by the Free Software Foundation; either version 2
  36 -- of the License, or (at your option) any later version.
  37
  38 -- This software is distributed in the hope that it will be useful,
  39 -- but WITHOUT ANY WARRANTY; without even the implied warranty of
  40 -- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  41 -- GNU General Public License for more details.
  42
  43 -- You should have received a copy of the GNU General Public License
  44 -- along with this program; if not, write to the Free Software
  45 -- Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  46
  47 -- Have a nice weather :)
  48
  49 local defaults = {
  50    update_interval = 30 * 60 * 1000, -- every 30 minutes
  51    station = "UMGG",
  52    timestamp_format = "%F %H:%M", -- strftime format
  53    gmt_offset = nil, -- offset from gmt in seconds. should be calculated automaticaly but may be specified manualy
  54 }
  55
  56 local settings = table.join(statusd.get_config("weather"), defaults)
  57
  58 local weather_timer = statusd.create_timer()
  59 local wget_timer = statusd.create_timer()
  60
  61 local get_weather
  62
  63 local function calculate_gmt_offset()
  64    -- offset (+|-)(\d\d)(\d\d)
  65    local off = {}
  66    _, _, off.sign, off.hour, off.min = string.find(os.date("%z", os.time()), "([-+])(%d%d)(%d%d)")
  67    settings.gmt_offset = (off.hour * 60 + off.min) * 60
  68    if off.sign == '-' then settings.gmt_offset = -settings.gmt_offset end
  69 end
  70
  71 local function reformat_time(date, time)
  72    local dt = {}
  73    _, _, dt.year, dt.month, dt.day = string.find(date, "(%d+)%.(%d+)%.(%d+)")
  74    _, _, dt.hour, dt.min = string.find(time, "(%d%d)(%d%d)")
  75    os.setlocale(os.getenv("LANG"), "time")
  76    return os.date(settings.timestamp_format, os.time(dt) + settings.gmt_offset)
  77 end
  78
  79 local function parse_weather(s)
  80    local w = {}
  81    _, _, w.location, w.country = string.find(s, "^(.+)%,%s(.+)%(%u+%)" )
  82    _, _, w.date, w.time = string.find(s, ".+%/%s([%d.]+)%s(%d+)%sUTC" )
  83    _, _, w.wind, w.windspeed = string.find(s, "Wind%:%s(.+%sat%s(%d+)%sMPH)" )
  84    _, _, w.sky = string.find(s, "Sky%sconditions:%s(.-)%c" )
  85    _, _, w.tempF, w.tempC = string.find(s, "Temperature:%s(-?%d*%.?%d+)%sF%s%((-?%d*%.?%d+)%sC%)%c" )
  86    _, _, w.dewpointF, w.dewpointC = string.find(s, "Dew%sPoint:%s(-?%d*%.?%d+)%sF%s%((-?%d*%.?%d+)%sC%)" )
  87    _, _, w.windchillF, w.windchillC = string.find(s, "Windchill:%s(-?%d*%.?%d+)%sF%s%((-?%d*%.?%d+)%sC%)" )
  88    _, _, w.humidity = string.find(s, "Relative%sHumidity:%s(%d+)%%")
  89    _, _, w.pressure = string.find(s, "Pressure%s%b():.-%((%d+)%shPa%)" )
  90    _, _, w.weather = string.find(s, "Weather:%s(.-)%c" )
  91    if w.date and w.time then
  92       w.timestamp = reformat_time(w.date, w.time)
  93    else
  94       w.timestamp = "undef"
  95    end
  96    return w
  97 end
  98
  99 local function load_weather()
 100    local f = io.open ("/tmp/".. settings.station..".dat")
 101    if not f then return nil end
 102    local s = f:read("*all")
 103    f:close()
 104    os.execute("rm ".."/tmp/".. settings.station..".dat")
 105    return parse_weather(s)
 106 end
 107
 108 local function update_weather()
 109    local w = load_weather()
 110    if w then
 111       for i,v in pairs(w) do
 112          if not v then v = "N/A" end
 113          statusd.inform("weather_"..i, v);
 114       end
 115    end
 116    weather_timer:set(settings.update_interval, get_weather)
 117 end
 118
 119 local function check_wget()
 120    local filename = "/tmp/wget_"..settings.station.."_status.txt"
 121    local f = io.open (filename)
 122    if not f then
 123        weather_timer:set(settings.update_interval, get_weather)
 124        return nil
 125    end
 126    local s = f:read("*all")
 127    f:close()
 128    if not string.match(s, "100%%") then
 129       -- wget still downloading. resetting timer
 130       wget_timer:set(2000, check_wget)
 131    else
 132       -- wget finished. so we need parse file and update info
 133       os.execute("rm "..filename)
 134       update_weather()
 135    end
 136 end
 137
 138 get_weather = function ()
 139                  local url = "http://weather.noaa.gov/pub/data/observations/metar/decoded/"
 140                  local command = "wget -b -o /tmp/wget_"..settings.station.."_status.txt -O /tmp/"..settings.station..".dat "..url..settings.station..".TXT"
 141                  os.execute(command)
 142                  -- start watching timer -- when wget will exit -- update weather
 143                  wget_timer:set(2000, check_wget)
 144               end
 145
 146 if not settings.gmt_offset then
 147    calculate_gmt_offset()
 148 end
 149 get_weather()