Net::ReadTimeout: Net::ReadTimeout and Selenium::W

2019-06-25 12:18发布

问题:

Enthusiastic about the baking of Capybara into the new version of Rails (5.1) cf http://weblog.rubyonrails.org/2017/2/23/Rails-5-1-beta1/

I have run into a problem though. Here are my steps. Any clue welcome.

Brand new install of:

  • Linux Ubuntu Desktop 16.10 (VM on Hyper-V), with Chrome installed and running fine;
  • Ruby 2.4;
  • Rails 5.1.beta.

1.- Create a simple app:

    ~$ ruby -v
    ruby 2.4.0p0 (2016-12-24 revision 57164) [x86_64-linux]
    ~$ rails -v
    Rails 5.1.0.beta1
    ~$ mkdir railsapps
    ~$ cd railsapps
    ~/railsapps$ rails new smoketestapp
    ~/railsapps$ cd smoketestapp
    ~/railsapps/smoketestapp$ rails generate scaffold post title:string body:text
    ~/railsapps/smoketestapp$ rails db:migrate

2.- Run the test

    ~/railsapps/smoketestapp$ cat test/system/posts_test.rb
    require "application_system_test_case"

    class PostsTest < ApplicationSystemTestCase
      test "visiting the index" do
        visit posts_url

        assert_selector "h1", text: "Post"
      end
    end

     ~/railsapps/smoketestapp$ rake test TEST=test/system/posts_test.rb
    Run options: --seed 55778

    # Running:
    ...
    Error:
    PostsTest#test_visiting_the_index:
    Selenium::WebDriver::Error::WebDriverError: Unable to find chromedriver. Please download the server from http://chromedriver.storage.googleapis.com/index.html and place it somewhere on your PATH. More info at https://github.com/SeleniumHQ/selenium/wiki/ChromeDriver.
    ...
    1 runs, 0 assertions, 0 failures, 1 errors, 0 skips
     ~/railsapps/smoketestapp$

3.- OK, let's proceed as suggested in the error messsage (install chromedriver) :

     ~/railsapps/smoketestapp$ ls /usr/bin/google-chrome
    lrwxrwxrwx 1 root root 31 Mar 18 15:31 /usr/bin/google-chrome -> /etc/alternatives/google-chrome*
     ~/railsapps/smoketestapp$ echo $PATH 
    ...:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:...
     ~/railsapps/smoketestapp$ wget https://chromedriver.storage.googleapis.com/2.28/chromedriver_linux64.zip
     ~/railsapps/smoketestapp$ unzip chromedriver_linux64.zip
     ~/railsapps/smoketestapp$ sudo cp chromedriver /usr/local/bin
     ~/railsapps/smoketestapp$ ls /usr/local/bin
    total 7504
    drwxr-xr-x  2 root root    4096 Mar 19 19:05 ./
    drwxr-xr-x 10 root root    4096 Okt 12 22:42 ../
    -rwxr-xr-x  1 root root 7673176 Mar 19 19:05 chromedriver*
     ~/railsapps/smoketestapp$

4.- OK. Retry test ...

     ~/railsapps/smoketestapp$ rake test TEST=test/system/posts_test.rb
    Run options: --seed 51574

    # Running:
    ...
    Error:
    PostsTest#test_visiting_the_index:
    Net::ReadTimeout: Net::ReadTimeout test/system/posts _test.rb:5:in `block in '
    ...
    bin/rails test test/system/posts_test.rb:4
    ...
    1 runs, 0 assertions, 0 failures, 1 errors, 0 skips
     ~/railsapps/smoketestapp$

Not OK!

A clue on the root cause of 'Net::ReadTimeout: Net::ReadTimeout' error message is given when running rails -v in the app dir, giving Selenium::WebDriver::Error::UnknownError: unknown error: Chrome failed to start:

    ~/railsapps/smoketestapp$ rails -v
    Run options: --seed 39896
    # Running:
    .......E
    Error:
    PostsTest#test_visiting_the_index:
    Selenium::WebDriver::Error::UnknownError: unknown error: Chrome failed to start: exited abnormally
      (Driver info: chromedriver=2.28.455506  (18f6627e265f442aeec9b6661a49fe819aeeea1f),platform=Linux 4.8.0-41-generic x86_64)
        test/system/posts_test.rb:5:in `block in <class:PostsTest>'
    Error:
    PostsTest#test_visiting_the_index:
    Net::ReadTimeout: Net::ReadTimeout

    bin/rails test test/system/posts_test.rb:4
    ...
    ~/railsapps/smoketestapp$

This is what I get when invoking the Selenium WebDriver directly from Ruby:

    ~/railsapps/smoketestapp$ irb
    2.4.0 :001 > require "selenium-webdriver"
     => true
    2.4.0 :002 > driver = Selenium::WebDriver.for(:chrome)
    Net::ReadTimeout: Net::ReadTimeout
    from ~/.rvm/rubies/ruby-2.4.0/lib/ruby/2.4.0/net/protocol.rb:176:in `rbuf_fill'
    from ~/.rvm/rubies/ruby-2.4.0/lib/ruby/2.4.0/net/protocol.rb:154:in `readuntil'
    from ~/.rvm/rubies/ruby-2.4.0/lib/ruby/2.4.0/net/protocol.rb:164:in `readline'
    from ~/.rvm/rubies/ruby-2.4.0/lib/ruby/2.4.0/net/http/response.rb:40:in `read_status_line'
    from ~/.rvm/rubies/ruby-2.4.0/lib/ruby/2.4.0/net/http/response.rb:29:in `read_new'
    from ~/.rvm/rubies/ruby-2.4.0/lib/ruby/2.4.0/net/http.rb:1446:in `block in transport_request'
    from ~/.rvm/rubies/ruby-2.4.0/lib/ruby/2.4.0/net/http.rb:1443:in `catch'
    from ~/.rvm/rubies/ruby-2.4.0/lib/ruby/2.4.0/net/http.rb:1443:in `transport_request'
    from ~/.rvm/rubies/ruby-2.4.0/lib/ruby/2.4.0/net/http.rb:1416:in `request'
    from ~/.rvm/rubies/ruby-2.4.0/lib/ruby/2.4.0/net/http.rb:1409:in `block in request'
    from ~/.rvm/rubies/ruby-2.4.0/lib/ruby/2.4.0/net/http.rb:877:in `start'
    from ~/.rvm/rubies/ruby-2.4.0/lib/ruby/2.4.0/net/http.rb:1407:in `request'
    from ~/.rvm/gems/ruby-2.4.0/gems/selenium-webdriver-3.3.0/lib/selenium/webdriver/remote/http/default.rb:124:in `response_for'
    from ~/.rvm/gems/ruby-2.4.0/gems/selenium-webdriver-3.3.0/lib/selenium/webdriver/remote/http/default.rb:78:in `request'
    from ~/.rvm/gems/ruby-2.4.0/gems/selenium-webdriver-3.3.0/lib/selenium/webdriver/remote/http/common.rb:61:in `call'
    from ~/.rvm/gems/ruby-2.4.0/gems/selenium-webdriver-3.3.0/lib/selenium/webdriver/remote/bridge.rb:669:in `raw_execute'
    from ~/.rvm/gems/ruby-2.4.0/gems/selenium-webdriver-3.3.0/lib/selenium/webdriver/remote/bridge.rb:108:in `create_session'
    from ~/.rvm/gems/ruby-2.4.0/gems/selenium-webdriver-3.3.0/lib/selenium/webdriver/remote/bridge.rb:71:in `initialize'
    from ~/.rvm/gems/ruby-2.4.0/gems/selenium-webdriver-3.3.0/lib/selenium/webdriver/chrome/bridge.rb:52:in `initialize'
    from ~/.rvm/gems/ruby-2.4.0/gems/selenium-webdriver-3.3.0/lib/selenium/webdriver/common/driver.rb:61:in `new'
    from ~/.rvm/gems/ruby-2.4.0/gems/selenium-webdriver-3.3.0/lib/selenium/webdriver/common/driver.rb:61:in `for'
    from ~/.rvm/gems/ruby-2.4.0/gems/selenium-webdriver-3.3.0/lib/selenium/webdriver.rb:87:in `for'
    from (irb):2
    from ~/.rvm/rubies/ruby-2.4.0/bin/irb:11:in `<main>'
    2.4.0 :003 > exit
    ~/railsapps/smoketestapp$

Any help appreciated, thank-you

Varus

Update:

Found the problem, looking into the log file for Selenium driver. To do that, I typed the following in IRB:

    require "selenium-webdriver"
    Selenium::WebDriver::Chrome.driver_path="/usr/local/bin/chromedriver"
    Selenium::WebDriver.for :chrome, :service_log_path => "/tmp/cd.log"
    driver = Selenium::WebDriver.for(:chrome)

Tailing the log file nailed it: chrome would not start:

    ~/railsapps/smoketestapp$ tail /tmp/cd.log
       ...
    [0.247][INFO]: Launching chrome: /opt/google/chrome/google-chrome --disable-background-networking --disable-client-side-phishing-detection --disable-component-update --disable-default-apps --disable-hang-monitor --disable-prompt-on-repost --disable-web-resources --enable-logging --full-memory-crash-report --ignore-certificate-errors --load-extension=/tmp/.org.chromium.Chromium.Pdre6o/internal --logging-level=1 --metrics-recording-only --no-first-run --password-store=basic --remote-debugging-port=12264 --safebrowsing-disable-auto-update --safebrowsing-disable-download-protection --use-mock-keychain --user-data-dir=/tmp/.org.chromium.Chromium.mHJaEd data:,
    [0.250][WARNING]: PAC support disabled because there is no system implementation
    [20.281][INFO]: RESPONSE InitSession unknown error: Chrome failed to start: exited abnormally
    ~/railsapps/smoketestapp$

In the end, I found out that invoking chrome remotely via PuTTY did not work (that's what I was doing all the way), although doing the same directly on the VM (in Terminal Server) worked.

On PuTTY:

    ~$ google-chrome
    [3938:3938:0320/213941.129923:ERROR:browser_main_loop.cc(279)] Gtk: cannot open display:

Whereas, directly on the VM it worked.

Unfortunately, my happiness was short-lived, as I ran into yet another error, but that's another story:

            irb(main):001:0> require "selenium-webdriver"
    => true
    irb(main):002:0> Selenium::WebDriver::Chrome.driver_path="/usr/local/bin/chromedriver"
    => "/usr/local/bin/chromedriver"
    irb(main):003:0> driver = Selenium::WebDriver.for(:chrome)
    => #<Selenium::WebDriver::Driver:0x59d7c889a916c6b8 browser=:chrome>
    irb(main):004:0> driver.navigate.to("http://www.google.com")
    Selenium::WebDriver::Error::UnknownError: unknown error: Runtime.executionContextCreated has invalid 'context': {"auxData":{"frameId":"10797.1","isDefault":true},"id":1,"name":"","origin":"://"}
      (Session info: chrome=57.0.2987.110)
      (Driver info: chromedriver=2.4.226074,platform=Linux 4.8.0-41-generic x86_64)
            from ~/.rvm/rubies/ruby-2.4.0/lib/ruby/gems/2.4.0/gems/selenium-webdriver-3.3.0/lib/selenium/webdriver/remote/response.rb:69:in `assert_ok'
            from ~/.rvm/rubies/ruby-2.4.0/lib/ruby/gems/2.4.0/gems/selenium-webdriver-3.3.0/lib/selenium/webdriver/remote/response.rb:32:in `initialize'
            from ~/.rvm/rubies/ruby-2.4.0/lib/ruby/gems/2.4.0/gems/selenium-webdriver-3.3.0/lib/selenium/webdriver/remote/http/common.rb:83:in `new'
            from ~/.rvm/rubies/ruby-2.4.0/lib/ruby/gems/2.4.0/gems/selenium-webdriver-3.3.0/lib/selenium/webdriver/remote/http/common.rb:83:in `create_response'
            from ~/.rvm/rubies/ruby-2.4.0/lib/ruby/gems/2.4.0/gems/selenium-webdriver-3.3.0/lib/selenium/webdriver/remote/http/default.rb:107:in `request'
            from ~/.rvm/rubies/ruby-2.4.0/lib/ruby/gems/2.4.0/gems/selenium-webdriver-3.3.0/lib/selenium/webdriver/remote/http/common.rb:61:in `call'
            from ~/.rvm/rubies/ruby-2.4.0/lib/ruby/gems/2.4.0/gems/selenium-webdriver-3.3.0/lib/selenium/webdriver/remote/bridge.rb:669:in `raw_execute'
            from ~/.rvm/rubies/ruby-2.4.0/lib/ruby/gems/2.4.0/gems/selenium-webdriver-3.3.0/lib/selenium/webdriver/remote/bridge.rb:647:in `execute'
            from ~/.rvm/rubies/ruby-2.4.0/lib/ruby/gems/2.4.0/gems/selenium-webdriver-3.3.0/lib/selenium/webdriver/remote/bridge.rb:120:in `get'
            from ~/.rvm/rubies/ruby-2.4.0/lib/ruby/gems/2.4.0/gems/selenium-webdriver-3.3.0/lib/selenium/webdriver/common/navigation.rb:32:in `to'
            from (irb):4
            from ~/.rvm/rubies/ruby-2.4.0/bin/irb:11:in `<main>'
    irb(main):005:0> exit

回答1:

Ultimately, I wanted to run system tests with Capybara that would work in my settings (development machine = VM with OS = Linux Ubuntu, accessed remotely through PuTTY).

I found a way to make it work.

For that, I ditched Chrome and its Selenium driver, for PhantomJS and poltergeist.

PhantomJS is a headless browser (= no GUI). It works great. Here are my steps (Rails 5.1):

  1. Add gem 'poltergeist' to your Gemfile, and comment out gem 'selenium-webdriver' (the later is needed by chrome, which we will not use):

    #gem 'selenium-webdriver'
    gem 'poltergeist'
    
  2. Run bundle update

  3. Add poltergeist driver config (in file application_system_test_case.rb), commenting out the chrome driver config:

    $ cat test/application_system_test_case.rb
    
    require "test_helper"
    
    require "capybara/poltergeist"
    Capybara.javascript_driver = :poltergeist      
    
    class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
      # driven_by :selenium, using: :chrome, screen_size: [1400, 1400]
      driven_by :poltergeist
    end
    
  4. download the 'PhamtomJS' headless browser, and place it on a directory in your PATH:

    $ wget https://bitbucket.org/ariya/phantomjs/downloads/phantomjs-1.9.8-linux-x86_64.tar.bz2
    $ tar -xjvf phantomjs-1.9.8-linux-x86_64.tar.bz2
    $ sudo cp phantomjs-1.9.8-linux-x86_64/bin/phantomjs /usr/local/bin
    $ sudo chmod +x /usr/local/bin/phantomjs
    
  5. You are all set, and ready to run a system test. For example:

    $ rake test TEST=test/system/posts_test.rb
    Run options: --seed 38196
    
    # Running:
    
    Puma starting in single mode...
    * Version 3.8.2 (ruby 2.4.0-p0), codename: Sassy Salamander
    * Min threads: 0, max threads: 1
    * Environment: test
    * Listening on tcp://0.0.0.0:44265
    Use Ctrl-C to stop
    You're running an old version of PhantomJS, update to >= 2.1.1 for a better experience.
    .
    
    Finished in 1.366478s, 0.7318 runs/s, 0.7318 assertions/s.
    
    1 runs, 1 assertions, 0 failures, 0 errors, 0 skips
    $