geocoders.rb in andre-geokit-1.2.1

- old
+ new

@@ -93,18 +93,33 @@
       def self.geocode(address)  
         res = do_geocode(address)
         return res.success ? res : GeoLoc.new
       end  
       
+      # Main method which calls the do_reverse_geocode template method which subclasses
+      # are responsible for implementing.  Returns a populated GeoLoc or an
+      # empty one with a failed success code.
+      def self.reverse_geocode(latlng)
+        res = do_reverse_geocode(latlng)
+        return res.success ? res : GeoLoc.new        
+      end
+      
       # Call the geocoder service using the timeout if configured.
       def self.call_geocoder_service(url)
         timeout(Geokit::Geocoders::timeout) { return self.do_get(url) } if Geokit::Geocoders::timeout        
         return self.do_get(url)
       rescue TimeoutError
         return nil  
       end
 
+      # Not all geocoders can do reverse geocoding. So, unless the subclass explicitly overrides this method,
+      # a call to reverse_geocode will return an empty GeoLoc. If you happen to be using MultiGeocoder,
+      # this will cause it to failover to the next geocoder, which will hopefully be one which supports reverse geocoding.
+      def self.do_reverse_geocode(latlng)
+        return GeoLoc.new
+      end
+
       protected
 
       def self.logger() 
         Geokit::Geocoders::logger
       end
@@ -191,28 +206,42 @@
     # Google geocoder implementation.  Requires the Geokit::Geocoders::GOOGLE variable to
     # contain a Google API key.  Conforms to the interface set by the Geocoder class.
     class GoogleGeocoder < Geocoder
 
       private 
+      
+      # Template method which does the reverse-geocode lookup.
+      def self.do_reverse_geocode(latlng)
+        res = self.call_geocoder_service("http://maps.google.com/maps/geo?ll=#{Geokit::Inflector::url_escape(latlng)}&output=xml&key=#{Geokit::Geocoders::google}&oe=utf-8")
+  #        res = Net::HTTP.get_response(URI.parse("http://maps.google.com/maps/geo?ll=#{Geokit::Inflector::url_escape(address_str)}&output=xml&key=#{Geokit::Geocoders::google}&oe=utf-8"))
+        return GeoLoc.new if !res.is_a?(Net::HTTPSuccess)
+        xml = res.body
+        logger.debug "Google reverse-geocoding. LL: #{latlng}. Result: #{xml}"
+        return self.xml2GeoLoc(xml)        
+      end
 
       # Template method which does the geocode lookup.
       def self.do_geocode(address)
         address_str = address.is_a?(GeoLoc) ? address.to_geocodeable_s : address
         res = self.call_geocoder_service("http://maps.google.com/maps/geo?q=#{Geokit::Inflector::url_escape(address_str)}&output=xml&key=#{Geokit::Geocoders::google}&oe=utf-8")
 #        res = Net::HTTP.get_response(URI.parse("http://maps.google.com/maps/geo?q=#{Geokit::Inflector::url_escape(address_str)}&output=xml&key=#{Geokit::Geocoders::google}&oe=utf-8"))
         return GeoLoc.new if !res.is_a?(Net::HTTPSuccess)
-        xml=res.body
+        xml = res.body
         logger.debug "Google geocoding. Address: #{address}. Result: #{xml}"
+        return self.xml2GeoLoc(xml)        
+      end
+      
+      def self.xml2GeoLoc(xml)
         doc=REXML::Document.new(xml)
 
         if doc.elements['//kml/Response/Status/code'].text == '200'
           res = GeoLoc.new
           coordinates=doc.elements['//coordinates'].text.to_s.split(',')
 
           #basics
           res.lat=coordinates[1]
           res.lng=coordinates[0]
-          res.country_code=doc.elements['//CountryNameCode'].text
+          res.country_code=doc.elements['//CountryNameCode'].text if doc.elements['//CountryNameCode']
           res.provider='google'
 
           #extended -- false if not not available
           res.city = doc.elements['//LocalityName'].text if doc.elements['//LocalityName']
           res.state = doc.elements['//AdministrativeAreaName'].text if doc.elements['//AdministrativeAreaName']
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