em-example.rb

require 'rubygems'
#require 'rubygems/user_interaction' # Required with some older RubyGems
require 'isolate/now'
 
require 'eventmachine'
require 'em-websocket'
require 'em-http'
require 'nokogiri'
require 'json'
require 'pp'
 
class GeoCodeQuery
  include EM::Deferrable
 
  def initialize(postal_code)
    query = {
      :postal => postal_code,
      :geoit => :xml
    }
    req = EM::HttpRequest.new('http://geocoder.ca/').get(:query => query)
    req.callback do
      doc = Nokogiri.parse(req.response)
      lat = doc.search('latt').inner_text
      long = doc.search('longt').inner_text
 
      succeed(lat, long)
    end
    req.errback { fail }
  end
end
 
# http://developer.foursquare.com/docs/venues/search.html
class FourSquareQuery
  include EM::Deferrable
 
  def initialize(lat, long)
    four_sq_query = {
      :ll => "#{lat},#{long}",
      :limit => 50,
      :intent => :checkin,
      :client_id => 'UKPXGFNLVLSH2HDXBCJ5TZQY0PNTNTZARBWGVO4XZM3Q3WA0',
      :client_secret => 'JP3Q2OIMBILSOHU0VANN3FA5K1RP1UJFEPPR2O4PAWHC401G'
    }
    four_sq = EM::HttpRequest.new('https://api.foursquare.com/v2/venues/search').get(
                      :query => four_sq_query)
    four_sq.callback do
      locations = []
 
      data = JSON.parse(four_sq.response)['response']['groups'].first
      data['items'].each do |item|
        locations << {:type => 'foursquare',
                      :name => item['name'],
                      :lat => item['location']['lat'],
                      :lng => item['location']['lng']}
      end
      succeed(locations)
    end
 
    four_sq.errback do
      puts "Foursquare Query Failed"
      fail('FourSquare')
    end
  end
end
 
# http://developers.facebook.com/docs/reference/api/checkin/
class FaceBookQuery
  include EM::Deferrable
 
  def initialize(lat, long)
    facebook_access_query = {
      :client_id => 156713821042399,
      :client_secret => 'acf0a9dd669e3c4f42cc8f12221a0163',
      :grant_type => 'client_credentials'
    }
    faq = EM::HttpRequest.new('https://graph.facebook.com/oauth/access_token').get(
                  :query => facebook_access_query)
    faq.callback do
      token = faq.response.match(/access_token=(.*)$/)[1]
 
      facebook_query = {
        :type => :place,
        :center => "#{lat},#{long}",
        :distance => 10000,
        :access_token => token
      }
      facebook = EM::HttpRequest.new('https://graph.facebook.com/search').get(:query => facebook_query)
      facebook.callback do
        locations = []
 
        data = JSON.parse(facebook.response)['data']
        data.each do |item|
          locations << {:type => 'facebook',
                        :name => item['name'],
                        :lat => item['location']['latitude'],
                        :lng => item['location']['longitude']}
        end
        succeed(locations)
      end
 
      facebook.errback do
        puts "Facebook Query Failed"
        fail("FaceBook")
      end
    end
 
    faq.errback do
      puts "Facebook access token request failed."
      fail("FaceBook")
    end
  end
end
 
EM.run do
  puts "Server started on 0.0.0.0:8080 (drag index.html to your browser)"
  EM::WebSocket.start(:host => '0.0.0.0', :port => 8080) do |websocket|
    websocket.onopen { puts "Client connected" }
 
    websocket.onmessage do |msg|
      geocode = GeoCode.new(msg)
      geocode.callback do |lat, long|
        websocket.send({:type => 'location', :lat => lat, :lng => long}.to_json)
 
        [FourSquareQuery, FaceBookQuery].each do |klass|
          g = klass.new(lat, long)
          g.callback { |locations| locations.each { |location| websocket.send(location.to_json) } }
          g.errback  { |type|      websocket.send({:error => "#{type} call failed."}.to_json) }
        end
      end
 
      geocode.errback do
        puts "Failed on geocode"
        websocket.send({:error => "Geocode call failed."}.to_json)
      end
    end
 
    websocket.onclose { puts "closed" }
    websocket.onerror { |e| puts "err #{e.inspect}" }
  end
end

synchrony-example.rb

require 'em-websocket'
require 'em-synchrony'
require 'em-synchrony/em-http'
require 'nokogiri'
require 'json'

def geocode_query(postal_code)
  query = {
    :postal => postal_code,
    :geoit => :xml
  }

  req = EM::HttpRequest.new('http://geocoder.ca/').get(:query => query)
  req.response_header.status == 200 or raise "Geocode failed with status: #{req.response_header.status} body: #{req.body}"

  doc = Nokogiri.parse(req.response)

  lat = doc.search('latt').inner_text
  long = doc.search('longt').inner_text

  [lat, long]
end

# http://developer.foursquare.com/docs/venues/search.html
def foursquare_query(lat, long)
  four_sq_query = {
    :ll => "#{lat},#{long}",
    :limit => 50,
    :intent => :checkin,
    :client_id => 'UKPXGFNLVLSH2HDXBCJ5TZQY0PNTNTZARBWGVO4XZM3Q3WA0',
    :client_secret => 'JP3Q2OIMBILSOHU0VANN3FA5K1RP1UJFEPPR2O4PAWHC401G'
  }

  four_sq = EM::HttpRequest.new('https://api.foursquare.com/v2/venues/search').get(:query => four_sq_query)
  four_sq.response_header.status == 200 or raise "Foursquare failed with status: #{four_sq.response_header.status} body: #{four_sq.body}"

  data = JSON.parse(four_sq.response)['response']['groups'].first
  data['items'].map do |item|
    {
      :type => 'foursquare',
      :name => item['name'],
      :lat => item['location']['lat'],
      :lng => item['location']['lng']
    }
  end
end

# http://developers.facebook.com/docs/reference/api/checkin/
def facebook_query(lat, long)
  facebook_access_query = {
    :client_id => 156713821042399,
    :client_secret => 'acf0a9dd669e3c4f42cc8f12221a0163',
    :grant_type => 'client_credentials'
  }

  faq = EM::HttpRequest.new('https://graph.facebook.com/oauth/access_token').get(:query => facebook_access_query)
  faq.response_header.status == 200 or raise "Facebook oauth failed with status: #{faq.response_header.status} body: #{faq.body}"

  token = faq.response[/access_token=(.*)/, 1]

  facebook_query = {
    :type => :place,
    :center => "#{lat},#{long}",
    :distance => 10000,
    :access_token => token
  }
  facebook = EM::HttpRequest.new('https://graph.facebook.com/search').get(:query => facebook_query)
  facebook.response_header.status == 200 or raise "Facebook failed with status: #{facebook.response_header.status} body: #{facebook.body}"

  data = JSON.parse(facebook.response)['data']
  data.map do |item|
    {
      :type => 'facebook',
      :name => item['name'],
      :lat => item['location']['latitude'],
      :lng => item['location']['longitude']
    }
  end
end

EM.synchrony do
  puts "Server started on 0.0.0.0:8080 (drag index.html to your browser)"
  EM::WebSocket.start(:host => '0.0.0.0', :port => 8080) do |websocket|
    websocket.onopen { puts "Client connected" }

    websocket.onmessage do |msg|
      Fiber.new do
        lat, long = geocode_query(msg)

        websocket.send({:type => 'location', :lat => lat, :lng => long}.to_json)

        [:foursquare_query, :facebook_query].each do |query|
          Fiber.new do
            locations = send(query, lat, long)
            locations.each { |location| websocket.send(location.to_json) }
          end.resume
        end
      end.resume
    end

    websocket.onclose { puts "closed" }
    websocket.onerror { |e| puts "err #{e.message}" }
  end
end