Namecheap API

api.rb

# app/models/namecheap/api.rb
module Namecheap
  class Api
    def initialize(client_ip)
      @client_ip = client_ip
    end

    def domain_available?(url)
      AvailabilityXmlResponse.new(
        availablility_api(url).body
      ).available?
    end

    private
    attr_reader :client_ip

    def availablility_api(url_to_check)
      @response ||= HTTParty.get(availability_url(url_to_check))
    end

    def availability_url(url_to_check)
      (<<-URL).strip.gsub(/\n/, '')
https://api.namecheap.com/xml.response?
ApiUser=#{ENV['NAMECHEAP_API_USER']}&
ApiKey=#{ENV['NAMECHEAP_API_KEY']}&
UserName=#{ENV['NAMECHEAP_USER_NAME']}&
Command=namecheap.domains.check&
ClientIp=#{client_ip}&
DomainList=#{url_to_check}
URL
    end
  end
end

availability_xml_response.rb

# app/models/namecheap/availability_xml_response.rb
module Namecheap
  class AvailabilityXmlResponse
    def initialize(content)
      self.content = content
    end

    def available?
      to_boolean(xml.css('DomainCheckResult')[0].attributes['Available'].value)
    end

    private
    attr_reader :content

    def content=(other_content)
      @content ||= Nokogiri::XML(other_content)
    end

    def to_boolean(str)
      str == 'true'
    end
  end
end

domain.rb

# app/models/namecheap/view/domain.rb

module Namecheap
  module View
    class Domain
      def initialize(url, availability)
        @url = url
        @availaibility = availability
      end

      def available?
        "It looks like the domain—#{url}—#{is_or_is_not} available"
      end

      private
      attr_reader :url, :availability

      def is_or_is_not
        (availability) ? "is" : "is not"
      end
    end
  end
end

domains_controller.rb

# app/controllers/domains_controller.rb
class DomainsController < ApplicationController
  def search
    client_ip = request.ip
    namecheap = Namecheap::Api.new(client_ip)
    url = params[:url]
    available = namecheap.domain_available?(params[:url])

    @domain = Namecheap::View::Domain.new(url, available)
  end
end

Gemfile

# ... rest of gemfile

gem 'httparty'
gem 'nokogiri'

routes.rb

# config/routes.rb
resources :domains, :only => [] do
  collection do
    get 'search'
  end
end

search.html.erb

<% # app/views/domains/search.html.erb %>

<%= @domain.available? %>