Re-structured the observation data, and integrated parsing system to …

…populate them automatically from the raw METAR data.

git-svn-id: http://django-weathertracking.googlecode.com/svn/trunk@4 696a86c2-f982-11dd-8259-6defae454439

weathertracking/admin.py

@@ -8,7 +8,7 @@ class WeatherStationAdmin(admin.ModelAdmin):
 
 class WeatherReportAdmin(admin.ModelAdmin):
     list_display = ('station', 'observation_time', 'temperature_celsius',
-        'wind_speed_kts', 'wind_direction', 'visibility_mi', 'cycle', 'sky_conditions')
+        'wind_speed_kts', 'wind_direction', 'visibility_mi', 'observation_cycle', 'sky_conditions')
     list_filter = ('station',)
     date_hierarchy = 'observation_time'
 

weathertracking/documentation/INSTALL.txt

@@ -1,6 +1,7 @@
 Dependencies:
   GeoDjango and its dependencies (http://geodjango.org/docs/install.html)
   A suitable spatial database that supports distance lookup (http://geodjango.org/docs/db-api.html#id38) - right now that means only PostgreSQL / PostGIS and Oracle
+  Metar - from http://homepage.mac.com/wtpollard/Software/FileSharing4.html
 
 Notes:
   You can without too much pain an suffering comment out the bits that require GeoDjango, but I personally will always be using those bits so my "official" distribution will include them.

weathertracking/models.py

@@ -1,4 +1,5 @@
 from django.contrib.gis.db import models
+from metar.Metar import Metar # available from http://homepage.mac.com/wtpollard/Software/FileSharing4.html
 
 class WeatherStationManager(models.GeoManager):
     def auto_poll(self):
@@ -38,26 +39,56 @@ def all(self, limit=None):
 class WeatherReport(models.Model):
     station = models.ForeignKey(WeatherStation)
     raw = models.TextField()
-    timestamp = models.DateTimeField(auto_now_add=True)
+    timestamp = models.DateTimeField(auto_now_add=True) # keep track of when it was retrieved - necessary because METARs don't include any month/year info
+
+    # denormalized data - obtainable by parsing the raw info, but stored for convenience of lookup
+    observation_type = models.CharField(max_length=5, null=True, blank=True) # METAR or SPECI
+    observation_mode = models.CharField(max_length=4, null=True, blank=True) # AUTO or COR (corrected)
+    observation_cycle = models.IntegerField(null=True, blank=True) # a number between 0 and 23
     observation_time = models.DateTimeField(null=True, blank=True)
-    temperature_celsius = models.DecimalField(max_digits=5, decimal_places=2)
-    temperature_fahrenheit = models.DecimalField(max_digits=5, decimal_places=2)
-    dewpoint_celsius = models.DecimalField(max_digits=5, decimal_places=2)
-    dewpoint_fahrenheit = models.DecimalField(max_digits=5, decimal_places=2)
-    wind_speed_kts = models.IntegerField()
-    wind_speed_meters_per_second = models.DecimalField(max_digits=10, decimal_places=7)
-    wind_speed_miles_per_hour = models.DecimalField(max_digits=10, decimal_places=7)
     wind_direction = models.IntegerField(null=True, blank=True)
     wind_compass = models.CharField(max_length=4, null=True, blank=True)
-    visibility_km = models.DecimalField(max_digits=10, decimal_places=7)
-    visibility_mi = models.DecimalField(max_digits=10, decimal_places=7)
-    humidity_percent = models.IntegerField()
-    barometric_pressure_mb = models.DecimalField(max_digits=14, decimal_places=10)
-    altimeter = models.DecimalField(max_digits=4, decimal_places=2)
-    cycle = models.IntegerField(null=True, blank=True)
-    sky_conditions = models.CharField(max_length=256)
+    wind_direction_from = models.IntegerField(null=True, blank=True) # used when the wind direction is variable and specified
+    wind_direction_to = models.IntegerField(null=True, blank=True)   # ^^^
+    wind_speed_kts = models.IntegerField(null=True, blank=True)
+    wind_speed_gust_kts = models.IntegerField(null=True, blank=True)
+    visibility_mi = models.DecimalField(max_digits=10, decimal_places=7, null=True, blank=True)
+    temperature_celsius = models.DecimalField(max_digits=5, decimal_places=2, null=True, blank=True)
+    temperature_fahrenheit = models.DecimalField(max_digits=5, decimal_places=2, null=True, blank=True)
+    dewpoint_celsius = models.DecimalField(max_digits=5, decimal_places=2, null=True, blank=True)
+    dewpoint_fahrenheit = models.DecimalField(max_digits=5, decimal_places=2, null=True, blank=True)
+    sky_conditions = models.TextField(null=True, blank=True)
 
     objects = WeatherReportManager()
 
+    def get_metar_object(self):
+        return Metar(self.raw)
+
+    def save(self, **kwargs):
+        "Populate all the denormalized data fields by using the metar class before saving."
+        metar = self.get_metar_object()
+
+        self.observation_time = metar.time
+        self.observation_cycle = metar.cycle
+        self.observation_type = metar.type
+        self.observation_mode = metar.mod
+        self.temperature_celsius = '%s' % metar.temp.value(units='c')
+        self.temperature_fahrenheit = '%s' % metar.temp.value(units='f')
+        self.dewpoint_celsius = '%s' % metar.dewpt.value(units='c')
+        self.dewpoint_fahrenheit = '%s' % metar.dewpt.value(units='f')
+        self.visibility_mi = '%s' % metar.vis.value(units='MI')
+        self.wind_direction = '%s' % int(metar.wind_dir.value())
+        self.wind_compass = metar.wind_dir.compass()
+        if metar.wind_dir_from:
+            self.wind_direction_from = '%s' % int(metar.wind_dir_from.value())
+        if metar.wind_dir_to:
+            self.wind_direction_to = '%s' % int(metar.wind_dir_to.value())
+        self.wind_speed_kts = '%s' % int(metar.wind_speed.value()) # metars will only return integers when using kts
+        if metar.wind_gust:
+            self.wind_speed_gust_kts = '%s' % int(metar.wind_gust.value())
+        self.sky_conditions = '%s' % metar.sky_conditions()
+
+        super(WeatherReport, self).save(**kwargs)
+
     def __unicode__(self):
         return u'%s' % self.raw