Class: Drifter::Geocoders::Google

Inherits:
Base
  • Object
show all
Defined in:
lib/drifter/geocoders/google.rb

Overview

This class adds support for Google’s geocoding API: code.google.com/apis/maps/documentation/geocoding/

Constant Summary collapse

GOOGLE_BASE_URI = 
'http://maps.googleapis.com/maps/api/geocode/json'

Class Method Summary collapse

Methods inherited from Base

last_error

Class Method Details

.base_uri ⇒ Object

nodoc



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# File 'lib/drifter/geocoders/google.rb', line 14

def self.base_uri
  GOOGLE_BASE_URI
end

.geocode(location, params = {}) ⇒ Object

This method works exactly like Drifter::Geocoders::Yahoo.geocode() See that method for more info. The returned Drifter::Location objects have the following attributes:

:address, :city, :state, :state_code, :country, :country_code,
:post_code, :lat, :lng

Additional google specific attributes can be accessed using the Location object’s data() method



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# File 'lib/drifter/geocoders/google.rb', line 28

def self.geocode(location, params={})

  params[:address] = location

  # check for reverse gecoding
  lat, lng = Drifter.extract_latlng(location)
  if lat && lng
    params.delete(:address)
    params[:latlng] = [lat, lng].join(',')
  end

  uri = query_uri(params)
  response = fetch(uri)

  # check for errors and return if necassary
  doc = JSON.parse(response)
  unless ["OK", "ZERO_RESULTS"].include?(doc["status"])
    @@last_error = { :code => doc["status"], :message => doc["status"] }
    return nil
  end

  # still here so safe to clear errors
  @@last_error = nil

  # is there anything to parse?
  return [] if doc["status"] == "ZERO_RESULTS"

  doc["results"].collect do |result|
    loc = Drifter::Location.new
    loc.raw_data_format = :hash
    loc.raw_data = result
    loc.geocoder = :google

    loc.address = result["formatted_address"]
    loc.lat = result["geometry"]["location"]["lat"]
    loc.lng = result["geometry"]["location"]["lng"]

    result["address_components"].each do |comp|
      loc.country_code = comp["short_name"] if comp["types"].include?("country")
      loc.country = comp["long_name"] if comp["types"].include?("country")
      loc.city = comp["long_name"] if comp["types"].include?("locality")
      loc.post_code = comp["long_name"] if comp["types"].include?("postal_code")
      loc.state = comp["long_name"] if comp["types"].include?("administrative_area_level_1")
      loc.state_code = comp["short_name"] if comp["types"].include?("administrative_area_level_1")
    end
    loc
  end

end

.query_uri(params = {}) ⇒ Object

Google requires a ‘sensor’ parameter. If none is set, it defaults to false See their docs for more info



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# File 'lib/drifter/geocoders/google.rb', line 81

def self.query_uri(params={})
  params[:sensor] ||= 'false'
  uri = URI.parse(base_uri)
  uri.query = hash_to_query_string(params)
  return uri
end