add weather support

Signed-off-by: Mattias Andrée <maandree@operamail.com>

1 files changed, 73 insertions, 0 deletions

diff --git a/src/weather.py b/src/weather.py
new file mode 100644
index 0000000..c3aa2f9
--- /dev/null
+++ b/src/weather.py
@@ -0,0 +1,73 @@
+#!/usr/bin/env python3
+
+# Copyright © 2014  Mattias Andrée (maandree@member.fsf.org)
+# 
+# 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 3 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, see <http://www.gnu.org/licenses/>.
+
+from subprocess import Popen, PIPE
+
+
+def weather(station):
+    '''
+    Get a brief weather report
+    
+    @param   station:str    The station's International Civil Aviation Organization airport code
+    @return  :(sky:str, visiblity:(:int, :float)?, weather:list<str>)
+                            The sky condition, visiblity and weather. Sky condition values include
+                            ‘clear’, ‘mostly clear’, ‘overcast’, ‘partly cloudy’, ‘mostly cloudy’
+                            and ‘obscured’. The visibility consists of two parameters: the first
+                            on indicates the the visiblity is a upper bound if the value is -1,
+                            a lower bound if +1, and approximate if 0; the second parameter is the
+                            visibility in kilometers. If the visibility is unknown the value will
+                            be `None`. The weather is a list that can, and often is, empty.
+    '''
+    url = 'http://weather.noaa.gov/pub/data/observations/metar/decoded/%s.TXT'
+    url %= station.upper()
+    proc = Popen(['wget', url, '-O', '-'], stdout = PIPE, stderr = PIPE)
+    output = proc.communicate()[0]
+    if not proc.returncode == 0:
+        return None
+    output = output.decode('utf-8', 'replace').split('\n')
+    output = [line.lower().split(': ') for line in output if ': ' in line]
+    output = dict([(line[0], ': '.join(line[1:])) for line in output])
+    sky_conditions = 'clear' if 'sky conditions' not in output else output['sky conditions']
+    visibility = None
+    try:
+        if 'visibility' in output:
+            visibility = output['visibility'].split(':')[0]
+            visibility = visibility.replace(' mile(s)', '')
+            visibility = visibility.replace(' miles', '')
+            visibility = visibility.replace(' mile', '')
+            visibility_eq = 0
+            if visibility.startswith('greater than '):
+                visibility_eq = 1
+                visibility = visibility[len('greater than '):]
+            if visibility.startswith('less than '):
+                visibility_eq = -1
+                visibility = visibility[len('less than '):]
+            if len(list(filter(lambda c : not (('0' <= c <= '9') or (c in ' /')), visibility))) == 0:
+                visibility = sum([eval(v) for v in visibility.split(' ')])
+                visibility = (visibility_eq, visibility * 1.609)
+            else:
+                visibility = None
+    except:
+        visibility = None
+    weather = '' if 'weather' not in output else output['weather']
+    weather = weather.replace(',', ';').replace(' with ', ';')
+    weather = weather.replace(' in the vicinity', '')
+    weather = weather.replace(' observed', '')
+    weather = weather.replace(' during the past hour', '')
+    weather = [w.replace(';', '').strip() for w in weather.split(';') if not w == '']
+    return (sky_conditions, visibility, weather)
+