lib/spatial_features/models/feature.rb in spatial_features-1.0.0 vs lib/spatial_features/models/feature.rb in spatial_features-1.0.1

@@ -33,10 +33,14 @@
     select('features.*, ST_IsValidReason(geog::geometry) AS invalid_geometry_message').where.not('ST_IsValid(geog::geometry)')
   end
 
   def envelope(buffer_in_meters = 0)
     envelope_json = JSON.parse(self.class.select("ST_AsGeoJSON(ST_Envelope(ST_Buffer(features.geog, #{buffer_in_meters})::geometry)) AS result").where(:id => id).first.result)
-    envelope_json["coordinates"].first.values_at(0,2)
+    envelope_json = envelope_json["coordinates"].first
+
+    raise "Can't calculate envelope for Feature #{self.id}" if envelope_json.blank?
+
+    return envelope_json.values_at(0,2)
   end
 
   private
 
   def cache_derivatives