selenium_helper.rb

require 'selenium/client'
require 'selenium/rspec/spec_helper'
require File.join(BASEDIR,'support/user_config.rb')

if defined? JRUBY_VERSION
  # jruby has it's own process-handling code, as 'fork' is unreliable in java
  require 'java'
end

class SeleniumHelper
  attr_accessor :max_timeout, :browser
  def initialize(user_config)
    @user_config = user_config
    @max_timeout = 45  # maximum allowed timeout
    @selenium_port = user_config['selenium.port']
    @selenium_browser = @user_config['selenium.browser.name']
    @selenium_process = nil
    @browser = nil
    start_selenium
    start_browser
  end

  def shutdown
    stop_selenium
  end

  private

  def start_selenium
    selenium_jar_path = File.expand_path(File.join(PRJDIR,"lib","selenium","selenium-server.jar"))
    raise "Can't find #{selenium_jar_path}" unless File.exists?(selenium_jar_path)
    cmd = "java -jar #{selenium_jar_path} -timeout #{@max_timeout} -port #{@selenium_port}"

    if defined? JRUBY_VERSION # java magic to run a process
      @selenium_process = java.lang.ProcessBuilder.new(cmd.split(" ")).redirectErrorStream(true).start
      # spawn a thread to redirect background process to log file
      $stderr.puts "selenium process started in background"
      output_stream_to_log(@selenium_process.getInputStream, "selenium.log")
    else # not java - use fork
      @selenium_process = Process.fork do
          # Note: you need to redirect stdout this way
          # - if you try using "cmd > selenium.log" ruby spawns a subprocess, which you can't kill
         $stdout.reopen(File.new("selenium.log", "w"))
         exec cmd
      end
      $stderr.puts "selenium process started with pid #{@selenium_process}"
    end
    sleep 2  # give it a chance to start
    $stderr.puts "Selenium output sent to selenium.log"
  end

  def start_browser
    begin
      base_url = "http://localhost"
      @browser = Selenium::Client::Driver.new("localhost", @selenium_port, @selenium_browser, base_url, @max_timeout)
      @browser.start_new_browser_session
    rescue Exception
      stop_selenium
      raise
    end
  end

  def stop_selenium
    $stderr.puts "killing background selenium task"
    # could open http://localhost:selenium_port/selenium-server/driver/?cmd=shutDown - but this is more reliable!
    if defined? JRUBY_VERSION
      @selenium_process.destroy
      $stderr.puts "and waiting..."
      @selenium_process.waitFor
    else
      Process.kill("HUP", @selenium_process)
      $stderr.puts "and waiting..."
      Process.wait
    end
    $stderr.puts "dead."
  end

  def output_stream_to_log(inputStream, logfilename)
    Thread.new do
      File.open(logfilename,"w") do |f|
        output = java.io.BufferedReader.new(java.io.InputStreamReader.new(inputStream))
        while (line = output.readLine) != nil
          f.puts line
        end
        output.close
      end
    end

  end
end