Geocoding

Geocoding capabilities can be utilized to Rhino with the already included geocoder gem. Models should be geocoded with the geocoded_by method and the after_validation callback. The geocode method can be used to trigger the geocoding process.

app/models/location.rb

class Location < ApplicationRecord
  geocoded_by :address
  after_validation :geocode, if: :will_save_change_to_address?
end

tip

The will_save_change_to_address? method is used to trigger the geocoding process only if the address has changed - this can help to avoid unnecessary API calls.

and reverse geocoding can be done with the reverse_geocoded_by method if latitude and longitude columns are already in the model:

app/models/location.rb

class Location < ApplicationRecord
  reverse_geocoded_by :latitude, :longitude
end

API Access

Enable the Geocoding API in the Google Cloud Console.

Get an API key from Google Cloud Credentials.

Configuration

Update config/initializers/geocoder.rb with your API key and the lookup service you want to use:

config/initializers/geocoder.rb

Geocoder.configure(
  # Geocoding options
  # timeout: 3,                 # geocoding service timeout (secs)
  lookup: :google,         # name of geocoding service (symbol)
  # ip_lookup: :ipinfo_io,      # name of IP address geocoding service (symbol)
  # language: :en,              # ISO-639 language code
  # use_https: false,           # use HTTPS for lookup requests? (if supported)
  # http_proxy: nil,            # HTTP proxy server (user:pass@host:port)
  # https_proxy: nil,           # HTTPS proxy server (user:pass@host:port)

  # API key for geocoding service
  api_key: ENV['GOOGLE_API_KEY'],

  # cache: nil,                 # cache object (must respond to #[], #[]=, and #del)
  # cache_prefix: 'geocoder:',  # prefix (string) to use for all cache keys

  # Exceptions that should not be rescued by default
  # (if you want to implement custom error handling);
  # supports SocketError and Timeout::Error
  # always_raise: [],

  # Calculation options
  # units: :mi,                 # :km for kilometers or :mi for miles
  # distances: :linear          # :spherical or :linear
)

Testing

test/test_helper.rb contains a default stub for the geocoder:

test/test_helper.rb

# Set the geocoder to test mode and give it a default stub
Geocoder.configure(lookup: :test, ip_lookup: :test)
Geocoder::Lookup::Test.set_default_stub(
  [
    {
      "coordinates" => [41.2565, -95.9345],
      "address" => "Omaha, NE, US",
      "state" => "Nebraska",
      "state_code" => "NE",
      "country" => "United States",
      "country_code" => "US"
    }
  ]
)

Add additional stubs for testing as needed.