Net::ReadTimeout on headless Firefox Watir-WebDriver cukes

Question

I started running into tons of these errors today:

Net::ReadTimeout (Net::ReadTimeout)
      /usr/local/rvm/rubies/ruby-2.0.0-p0/lib/ruby/2.0.0/net/protocol.rb:158:in `rescue in rbuf_fill'
      /usr/local/rvm/rubies/ruby-2.0.0-p0/lib/ruby/2.0.0/net/protocol.rb:152:in `rbuf_fill'
      /usr/local/rvm/rubies/ruby-2.0.0-p0/lib/ruby/2.0.0/net/protocol.rb:134:in `readuntil'
      /usr/local/rvm/rubies/ruby-2.0.0-p0/lib/ruby/2.0.0/net/protocol.rb:144:in `readline'
      /usr/local/rvm/rubies/ruby-2.0.0-p0/lib/ruby/2.0.0/net/http/response.rb:39:in `read_status_line'
      /usr/local/rvm/rubies/ruby-2.0.0-p0/lib/ruby/2.0.0/net/http/response.rb:28:in `read_new'
      /usr/local/rvm/rubies/ruby-2.0.0-p0/lib/ruby/2.0.0/net/http.rb:1405:in `block in transport_request'
      /usr/local/rvm/rubies/ruby-2.0.0-p0/lib/ruby/2.0.0/net/http.rb:1402:in `catch'
      /usr/local/rvm/rubies/ruby-2.0.0-p0/lib/ruby/2.0.0/net/http.rb:1402:in `transport_request'
      /usr/local/rvm/rubies/ruby-2.0.0-p0/lib/ruby/2.0.0/net/http.rb:1375:in `request'
      /usr/local/rvm/rubies/ruby-2.0.0-p0/lib/ruby/2.0.0/net/http.rb:1368:in `block in request'
      /usr/local/rvm/rubies/ruby-2.0.0-p0/lib/ruby/2.0.0/net/http.rb:851:in `start'
      /usr/local/rvm/rubies/ruby-2.0.0-p0/lib/ruby/2.0.0/net/http.rb:1366:in `request'

I'm running headless (via headless gem) Watir-WebDriver cukes on Firefox 21, Ubuntu server. Here's the active bundle of gems:

Gems included by the bundle:
  * builder (3.2.2)
  * bundler (1.3.5)
  * childprocess (0.3.9)
  * cucumber (1.3.2)
  * cwtestgen (0.1.6)
  * data_magic (0.14)
  * diff-lcs (1.2.4)
  * faker (1.1.2)
  * ffi (1.8.1)
  * gherkin (2.12.0)
  * headless (1.0.1)
  * i18n (0.6.4)
  * multi_json (1.7.5)
  * page-object (0.8.10)
  * page_navigation (0.9)
  * require_all (1.2.1)
  * rspec (2.13.0)
  * rspec-core (2.13.1)
  * rspec-expectations (2.13.0)
  * rspec-mocks (2.13.1)
  * rubyzip (0.9.9)
  * selenium-webdriver (2.33.0)
  * syntax (1.0.0)
  * thor (0.18.1)
  * watir-webdriver (0.6.4)
  * watir-webdriver-performance (0.2.2)
  * websocket (1.0.7)
  * yml_reader (0.2)

I don't even know where to begin resolving this issue. The timeouts are random. They do not occur when I run these tests on Firefox 21 on OS X (not headless). Has anyone experienced this before? ANY and ALL ideas much appreciated -- thank you!

Answer 1

I ran into this problem. I do not know why it happens but I found a solution to it. I just terminate the watir browser and headless, then I retry. The problem is that watir loosed the connection to the browser so it cannot be terminated. I think it is a part of the initial problem. To terminate the watir browser I dump the browser object with YAML then parse the result to find the pid of the emulated browser. After it's done the kill command is send to the right pid. Finally the browser and headless are reinitialized.

tryLeft = 3
begin
  @watir.goto url
rescue => error
  tryLeft -= 1

  if tryLeft >= 0
    sleep 1
    retry
  end

  begin
    Timeout::timeout(2) { @watir.close }
  rescue
    File.open(@tmpDumpFile, 'w') { |file| file << YAML::dump(@watir) }
    `awk '/pid:/ {print $2;}' "#{@tmpDumpFile}" | xargs -rt kill 2>&1`
    FileUtils.rm_f(@tmpDumpFile)
  end

  @headless.stop
  `killall Xvfb 2>&1`

  # Reinitialize @watir / @headless then retry
end