teamcapybara--capybara/lib/capybara/server.rb

require 'uri'
require 'net/http'
require 'rack'
require 'capybara/util/timeout'

module Capybara
  class Server
    class Identify
      def initialize(app)
        @app = app
      end

      def call(env)
        if env["PATH_INFO"] == "/__identify__"
          [200, {}, @app.object_id.to_s]
        else
          @app.call(env)
        end
      end
    end

    attr_reader :app, :port

    def initialize(app)
      @app = app
    end

    def host
      "localhost" 
    end

    def url(path)
      if path =~ /^http/
        path
      else
        (Capybara.app_host || "http://#{host}:#{port}") + path.to_s
      end
    end

    def responsive?
      is_running_on_port?(port)
    end

    def handler
      begin
        require 'rack/handler/thin'
        Rack::Handler::Thin
      rescue LoadError
        begin
          require 'rack/handler/mongrel'
          Rack::Handler::Mongrel
        rescue LoadError
          require 'rack/handler/webrick'
          Rack::Handler::WEBrick
        end
      end
    end

    def boot
      return self unless @app
      find_available_port
      Capybara.log "application has already booted" and return self if responsive?
      Capybara.log "booting Rack applicartion on port #{port}"

      Thread.new do
        handler.run(Identify.new(@app), :Port => port, :AccessLog => [])
      end
      Capybara.log "checking if application has booted"

      Capybara.timeout(10) do
        if responsive?
          Capybara.log("application has booted")
          true
        else
          sleep 0.5
          false
        end
      end
      self
    rescue Timeout::Error
      Capybara.log "Rack application timed out during boot"
      exit
    end

  private

    def find_available_port
      @port = 9887
      @port += 1 while is_port_open?(@port) and not is_running_on_port?(@port)
    end

    def is_running_on_port?(tested_port)
      res = Net::HTTP.start(host, tested_port) { |http| http.get('/__identify__') }

      if res.is_a?(Net::HTTPSuccess) or res.is_a?(Net::HTTPRedirection)
        return res.body == @app.object_id.to_s
      end
    rescue Errno::ECONNREFUSED, Errno::EBADF
      return false
    end

    def is_port_open?(tested_port)
      Timeout::timeout(1) do
        begin
          s = TCPSocket.new(host, tested_port)
          s.close
          return true
        rescue Errno::ECONNREFUSED, Errno::EHOSTUNREACH
          return false
        end
      end
    rescue Timeout::Error
      return false
    end

  end
end