Geokit ====== [![Gem Version](https://badge.fury.io/rb/geokit.png)](http://badge.fury.io/rb/geokit) [![Build Status](https://travis-ci.org/geokit/geokit.png?branch=master)](https://travis-ci.org/geokit/geokit) [![Coverage Status](https://coveralls.io/repos/geokit/geokit/badge.png)](https://coveralls.io/r/geokit/geokit) [![Dependency Status](https://gemnasium.com/geokit/geokit.png)](https://gemnasium.com/geokit/geokit) [![Code Climate](https://codeclimate.com/github/geokit/geokit.png)](https://codeclimate.com/github/geokit/geokit) ## DESCRIPTION The Geokit gem provides: * Distance calculations between two points on the earth. Calculate the distance in miles, kilometers, or nautical miles, with all the trigonometry abstracted away by Geokit. * Geocoding from multiple providers. It supports Google, Yahoo, Geocoder.us, and Geocoder.ca geocoders, and others. It provides a uniform response structure from all of them. It also provides a fail-over mechanism, in case your input fails to geocode in one service. * Rectangular bounds calculations: is a point within a given rectangular bounds? * Heading and midpoint calculations Combine this gem with the [geokit-rails](http://github.com/geokit/geokit-rails) to get location-based finders for your Rails app. * Repository at Github: [http://github.com/geokit/geokit](http://github.com/geokit/geokit). * RDoc pages: [http://rdoc.info/github/geokit/geokit/master/frames](http://rdoc.info/github/geokit/geokit/master/frames) ## COMMUNICATION * If you **need help**, use [Stack Overflow](http://stackoverflow.com/questions/tagged/geokit). (Tag 'geokit' and we'll be alerted) * If you **found a bug**, use GitHub issues. * If you **have an idea**, use GitHub issues. * If you'd like to **ask a general question**, use GitHub issues. * If you **want to contribute**, submit a pull request. ## INSTALL gem install geokit ## SUPPORTED GEOCODERS ### "regular" address geocoders * Yahoo BOSS - requires an API key. * Geocoder.us - may require authentication if performing more than the free request limit. * Geocoder.ca - for Canada; may require authentication as well. * Geonames - a free geocoder * Bing * Yandex * MapQuest ### address geocoders that also provide reverse geocoding * Google - requires an API key. Also supports multiple results and bounding box/country code biasing. * FCC * Open Street Map ### IP address geocoders * IP - geocodes an IP address using hostip.info's web service. * Geoplugin.net -- another IP address geocoder * RIPE * MaxMind * freegeoip.net ## QUICK START ```ruby irb> require 'rubygems' irb> require 'geokit' irb> a=Geokit::Geocoders::GoogleGeocoder.geocode '140 Market St, San Francisco, CA' irb> a.ll => 37.79363,-122.396116 irb> b=Geokit::Geocoders::GoogleGeocoder.geocode '789 Geary St, San Francisco, CA' irb> b.ll => 37.786217,-122.41619 irb> a.distance_to(b) => 1.21120007413626 irb> a.heading_to(b) => 244.959832435678 irb(main):006:0> c=a.midpoint_to(b) # what's halfway from a to b? irb> c.ll => "37.7899239257175,-122.406153503469" irb(main):008:0> d=c.endpoint(90,10) # what's 10 miles to the east of c? irb> d.ll => "37.7897825005142,-122.223214776155" ``` FYI, that `.ll` method means "latitude longitude". See the RDOC more more ... there are also operations on rectangular bounds (e.g., determining if a point is within bounds, find the center, etc). ## CONFIGURATION If you're using this gem by itself, here are the configuration options: ```ruby # These defaults are used in Geokit::Mappable.distance_to and in acts_as_mappable Geokit::default_units = :miles Geokit::default_formula = :sphere # This is the timeout value in seconds to be used for calls to the geocoder web # services. For no timeout at all, comment out the setting. The timeout unit # is in seconds. Geokit::Geocoders::request_timeout = 3 # This setting can be used if web service calls must be routed through a proxy. # These setting can be nil if not needed, otherwise, a valid URI must be # filled in at a minimum. If the proxy requires authentication, the username # and password can be provided as well. Geokit::Geocoders::proxy = 'https://user:password@host:port' # This is your yahoo application key for the Yahoo Geocoder. # See http://developer.yahoo.com/faq/index.html#appid # and http://developer.yahoo.com/maps/rest/V1/geocode.html Geokit::Geocoders::YahooGeocoder.key = 'REPLACE_WITH_YOUR_YAHOO_KEY' Geokit::Geocoders::YahooGeocoder.secret = 'REPLACE_WITH_YOUR_YAHOO_SECRET' # This is your Google Maps geocoder keys (all optional). # See http://www.google.com/apis/maps/signup.html # and http://www.google.com/apis/maps/documentation/#Geocoding_Examples Geokit::Geocoders::GoogleGeocoder.client_id = '' Geokit::Geocoders::GoogleGeocoder.cryptographic_key = '' Geokit::Geocoders::GoogleGeocoder.channel = '' # You can also set multiple API KEYS for different domains that may be directed to this same application. # The domain from which the current user is being directed will automatically be updated for Geokit via # the GeocoderControl class, which gets it's begin filter mixed into the ActionController. # You define these keys with a Hash as follows: #Geokit::Geocoders::google = { 'rubyonrails.org' => 'RUBY_ON_RAILS_API_KEY', 'ruby-docs.org' => 'RUBY_DOCS_API_KEY' } # This is your username and password for geocoder.us. # To use the free service, the value can be set to nil or false. For # usage tied to an account, the value should be set to username:password. # See http://geocoder.us # and http://geocoder.us/user/signup Geokit::Geocoders::UsGeocoder.key = 'username:password' # This is your authorization key for geocoder.ca. # To use the free service, the value can be set to nil or false. For # usage tied to an account, set the value to the key obtained from # Geocoder.ca. # See http://geocoder.ca # and http://geocoder.ca/?register=1 Geokit::Geocoders::CaGeocoder.key = 'KEY' # Most other geocoders need either no setup or a key Geokit::Geocoders::BingGeocoder.key = '' Geokit::Geocoders::GeonamesGeocoder.key = '' Geokit::Geocoders::MapQuestGeocoder.key = '' Geokit::Geocoders::YandexGeocoder.key = '' # require "external_geocoder.rb" # Please see the section "writing your own geocoders" for more information. # Geokit::Geocoders::external_key = 'REPLACE_WITH_YOUR_API_KEY' # This is the order in which the geocoders are called in a failover scenario # If you only want to use a single geocoder, put a single symbol in the array. # Valid symbols are :google, :yahoo, :us, and :ca. # Be aware that there are Terms of Use restrictions on how you can use the # various geocoders. Make sure you read up on relevant Terms of Use for each # geocoder you are going to use. Geokit::Geocoders::provider_order = [:google,:us] # The IP provider order. Valid symbols are :ip,:geo_plugin. # As before, make sure you read up on relevant Terms of Use for each. # Geokit::Geocoders::ip_provider_order = [:external,:geo_plugin,:ip] ``` ### Google Geocoder Tricks The Google Geocoder sports a number of useful tricks that elevate it a little bit above the rest of the currently supported geocoders. For starters, it returns a `suggested_bounds` property for all your geocoded results, so you can more easily decide where and how to center a map on the places you geocode. Here's a quick example: ```ruby irb> res = Geokit::Geocoders::GoogleGeocoder.geocode('140 Market St, San Francisco, CA') irb> pp res.suggested_bounds #, @sw=#> In addition, you can use viewport or country code biasing to make sure the geocoders prefers results within a specific area. Say we wanted to geocode the city of Syracuse in Italy. A normal geocoding query would look like this: irb> res = Geokit::Geocoders::GoogleGeocoder.geocode('Syracuse') irb> res.full_address => "Syracuse, NY, USA" ``` Not exactly what we were looking for. We know that Syracuse is in Italy, so we can tell the Google Geocoder to prefer results from Italy first, and then wander the Syracuses of the world. To do that, we have to pass Italy's ccTLD (country code top-level domain) to the `:bias` option of the `geocode` method. You can find a comprehensive list of all ccTLDs here: http://en.wikipedia.org/wiki/CcTLD. ```ruby irb> res = Geokit::Geocoders::GoogleGeocoder.geocode('Syracuse', :bias => 'it') irb> res.full_address => "Syracuse, Italy" ``` Alternatively, we can speficy the geocoding bias as a bounding box object. Say we wanted to geocode the Winnetka district in Los Angeles. ```ruby irb> res = Geokit::Geocoders::GoogleGeocoder.geocode('Winnetka') irb> res.full_address => "Winnetka, IL, USA" ``` Not it. What we can do is tell the geocoder to return results only from in and around LA. ```ruby irb> la_bounds = Geokit::Geocoders::GoogleGeocoder.geocode('Los Angeles').suggested_bounds irb> res = Geokit::Geocoders::GoogleGeocoder.geocode('Winnetka', :bias => la_bounds) irb> res.full_address => "Winnetka, California, USA" ``` ### The Multigeocoder Multi Geocoder - provides failover for the physical location geocoders, and also IP address geocoders. Its configured by setting Geokit::Geocoders::provider_order, and Geokit::Geocoders::ip_provider_order. You should call the Multi-Geocoder with its :geocode method, supplying one address parameter which is either a real street address, or an ip address. For example: ```ruby Geokit::Geocoders::MultiGeocoder.geocode("900 Sycamore Drive") Geokit::Geocoders::MultiGeocoder.geocode("12.12.12.12") ``` ## MULTIPLE RESULTS Some geocoding services will return multple results if the there isn't one clear result. Geoloc can capture multiple results through its "all" method. Currently only the Google geocoder supports multiple results: ```ruby irb> geo=Geokit::Geocoders::GoogleGeocoder.geocode("900 Sycamore Drive") irb> geo.full_address => "900 Sycamore Dr, Arkadelphia, AR 71923, USA" irb> geo.all.size irb> geo.all.each { |e| puts e.full_address } 900 Sycamore Dr, Arkadelphia, AR 71923, USA 900 Sycamore Dr, Burkburnett, TX 76354, USA 900 Sycamore Dr, TN 38361, USA .... ``` geo.all is just an array of additional Geolocs, so do what you want with it. If you call .all on a geoloc that doesn't have any additional results, you will get an array of one. ## NOTES ON WHAT'S WHERE mappable.rb contains the Mappable module, which provides basic distance calculation methods, i.e., calculating the distance between two points. LatLng is a simple container for latitude and longitude, but it's made more powerful by mixing in the above-mentioned Mappable module -- therefore, you can calculate easily the distance between two LatLng ojbects with `distance = first.distance_to(other)` GeoLoc represents an address or location which has been geocoded. You can get the city, zipcode, street address, etc. from a GeoLoc object. GeoLoc extends LatLng, so you also get lat/lng AND the Mappable module goodness for free. geocoders.rb contains all the geocoder implemenations. All the gercoders inherit from a common base (class Geocoder) and implement the private method do_geocode. ## WRITING YOUR OWN GEOCODERS If you would like to write your own geocoders, you can do so by requiring 'geokit' or 'geokit/geocoders.rb' in a new file and subclassing the base class (which is class "Geocoder"). You must then also require such extenal file back in your main geokit configuration. ```ruby require "geokit" module Geokit module Geocoders # and use :my to specify this geocoder in your list of geocoders. class MyGeocoder < Geocoder # Use via: Geokit::Geocoders::MyGeocoder.key = 'MY KEY' config :key private def self.do_geocode(address, options = {}) # Main geocoding method end def self.parse_json(json) # Helper method to parse http response. See geokit/geocoders.rb. end end end end ```