Remove pywapi dependency from weather module

The python-weather-api seems currently unmaintained and provides a thin
wrapper around the XML structure output from weather.com

i3pystatus/weather.py

@@ -1,11 +1,15 @@
 from i3pystatus import IntervalModule
-import pywapi
 from i3pystatus.core.util import internet, require
 
+from urllib.request import urlopen
+import re
+import xml.etree.ElementTree as ElementTree
+
+WEATHER_COM_URL = 'http://wxdata.weather.com/wxdata/weather/local/%s?unit=%s&cc=*'
 
 class Weather(IntervalModule):
     """
-    This module gets the weather from weather.com using pywapi module
+    This module gets the weather from weather.com.
     First, you need to get the code for the location from the www.weather.com
 
     .. rubric:: Available formatters
@@ -14,7 +18,6 @@ class Weather(IntervalModule):
     * {current_wind}
     * {humidity}
 
-    Requires pywapi from PyPI.
     """
 
     interval = 20
@@ -27,6 +30,7 @@ class Weather(IntervalModule):
     )
     required = ("location_code",)
 
+    location_code = None
     units = "metric"
     format = "{current_temp}"
     colorize = False
@@ -40,9 +44,34 @@ class Weather(IntervalModule):
         "default": ("", None),
     }
 
+    def fetch_weather(self):
+        '''Fetches the current weather from wxdata.weather.com service.'''
+        unit = '' if self.units == 'imperial' or self.units == '' else 'm'
+        url = WEATHER_COM_URL % (self.location_code, unit)
+        with urlopen(url) as handler:
+            try:
+                content_type = dict(handler.getheaders())['Content-Type']
+                charset = re.search(r'charset=(.*)', content_type).group(1)
+            except AttributeError:
+                charset = 'utf-8'
+            xml = handler.read().decode(charset)
+        doc = ElementTree.XML(xml)
+        return dict(
+            current_conditions=dict(
+                text=doc.findtext('cc/t'),
+                temperature=doc.findtext('cc/tmp'),
+                humidity=doc.findtext('cc/hmid'),
+                wind=dict(text=doc.findtext('cc/wind/t'), speed=doc.findtext('cc/wind/s'))
+                ),
+            units=dict(
+                temperature=doc.findtext('head/ut'),
+                speed=doc.findtext('head/us'),
+                ),
+            )
+
     @require(internet)
     def run(self):
-        result = pywapi.get_weather_from_weather_com(self.location_code, self.units)
+        result = self.fetch_weather()
         conditions = result["current_conditions"]
         temperature = conditions["temperature"]
         humidity = conditions["humidity"]
@@ -61,6 +90,10 @@ class Weather(IntervalModule):
             color = color
 
         self.output = {
-            "full_text": self.format.format(current_temp=current_temp, current_wind=current_wind, humidity=humidity),
+            "full_text": self.format.format(
+                current_temp=current_temp,
+                current_wind=current_wind,
+                humidity=humidity,
+                ),
             "color": color
         }