added METAR

rowers/weather.py

@@ -1,5 +1,7 @@
 import requests
 import json
+from lxml import objectify,etree
+import xml.etree.ElementTree as ET
 import time
 from datetime import datetime
 from rowingdata import rowingdata,geo_distance
@@ -31,6 +33,52 @@ def get_weather_data(long,lat,unixtime):
     else:
 	return 0
 
+# Get Metar data
+def get_metar_data(airportcode,unixtime):
+
+    timestamp = datetime.utcfromtimestamp(unixtime).isoformat()+'Z'
+
+    url = "https://www.aviationweather.gov/adds/dataserver_current/httpparam?dataSource=metars&requestType=retrieve&format=xml&startTime="
+    url += str(unixtime-3600)
+    url += "&endTime="
+    url += str(unixtime+3600)
+    url += "&stationString="+airportcode
+
+    s = requests.get(url)
+
+    if s.ok:
+        doc = etree.fromstring(s.content)
+        id = doc.xpath('data/METAR/station_id')[0].text
+        temp_c = doc.xpath('data/METAR/temp_c')[0].text
+        wind_dir = doc.xpath('data/METAR/wind_dir_degrees')[0].text
+        wind_speed = doc.xpath('data/METAR/wind_speed_kt')[0].text
+        timestamp = doc.xpath('data/METAR/observation_time')[0].text
+        rawtext = doc.xpath('data/METAR/raw_text')[0].text
+
+        print temp_c,wind_dir,wind_speed
+        
+        windbearing = float(wind_dir)
+        wind_knots = float(wind_speed)
+        wind_ms = 0.514444*wind_knots
+        wind_ms = int(10*wind_ms)/10.
+        
+        temperaturec = float(temp_c)
+        temp_f = 32.+(9./5.)*temperaturec
+        temp_f = str(int(10*temp_f)/10.)
+
+        message = 'Summary for your location at '+timestamp+': '
+        message += 'Temperature '+temp_c+'C/'+temp_f+'F'
+	message += '. Wind: '+str(wind_ms)+' m/s ('+str(wind_knots)+' kt)'
+        message +='. Wind Bearing: '+str(windbearing)+' degrees'
+#        message +='\n'+rawtext
+        
+        return [wind_ms,windbearing,message,rawtext,timestamp]
+
+
+    message = 'Failed to download METAR data'
+    return [0,0,message,'',timestamp]
+
+    
 # Get wind data (and translate from knots to m/s)
 def get_wind_data(lat,long,unixtime):
     data = get_weather_data(lat,long,unixtime)