用capybara-webkit检测到死锁

Question

我试图通过这个规范：

scenario "Edit a service", js: true do
  service = create_service_for(provider, title: "First service")
  fill_edit_service_form(service)
  expect(page).to have_css('#price', text: '10,00 $')
end

这是使用水豚的标准导轨规格。 我使用capybara-webkit用于javascript的所有场景。 当我试图传递它时，有时候它会起作用，有时它标记的数据库中有一条丢失的记录，有时我有这个错误：

Run options: include {:locations=>{"./spec/acceptances/provider_services_spec.rb"=>[31]}}
[K  1) Provider Services Edit a service
     Failure/Error: Unable to find matching line from backtrace
     ActiveRecord::StatementInvalid:
       PG::TRDeadlockDetected: ERROR:  deadlock detected
       DETAIL:  Process 24164 waits for AccessExclusiveLock on relation 3446991 of database 3446538; blocked by process 24184.
       Process 24184 waits for AccessShareLock on relation 3446902 of database 3446538; blocked by process 24164.
       HINT:  See server log for query details.
       : ALTER TABLE "active_admin_comments" DISABLE TRIGGER ALL;ALTER TABLE "provider_service_territory_provideds" DISABLE TRIGGER ALL;ALTER TABLE "provider_services" DISABLE TRIGGER ALL;ALTER TABLE "provider_divisions" DISABLE TRIGGER ALL;ALTER TABLE "provider_profiles" DISABLE TRIGGER ALL;ALTER TABLE "provider_service_intervention_level_provideds" DISABLE TRIGGER ALL;ALTER TABLE "provider_service_medium_provideds" DISABLE TRIGGER ALL;ALTER TABLE "provider_service_service_provideds" DISABLE TRIGGER ALL;ALTER TABLE "regions" DISABLE TRIGGER ALL;ALTER TABLE "service_formulas" DISABLE TRIGGER ALL;ALTER TABLE "region_translations" DISABLE TRIGGER ALL;ALTER TABLE "artists" DISABLE TRIGGER ALL;ALTER TABLE "admin_users" DISABLE TRIGGER ALL;ALTER TABLE "schema_migrations" DISABLE TRIGGER ALL;ALTER TABLE "services" DISABLE TRIGGER ALL;ALTER TABLE "services_provided" DISABLE TRIGGER ALL;ALTER TABLE "territories_provided" DISABLE TRIGGER ALL;ALTER TABLE "users" DISABLE TRIGGER ALL;ALTER TABLE "countries" DISABLE TRIGGER ALL;ALTER TABLE "coupons" DISABLE TRIGGER ALL;ALTER TABLE "currencies" DISABLE TRIGGER ALL;ALTER TABLE "formulas" DISABLE TRIGGER ALL;ALTER TABLE "collector_profiles" DISABLE TRIGGER ALL;ALTER TABLE "country_translations" DISABLE TRIGGER ALL;ALTER TABLE "images" DISABLE TRIGGER ALL;ALTER TABLE "intervention_levels_provided" DISABLE TRIGGER ALL;ALTER TABLE "measure_units" DISABLE TRIGGER ALL;ALTER TABLE "media_provided" DISABLE TRIGGER ALL;ALTER TABLE "messages" DISABLE TRIGGER ALL;ALTER TABLE "page_part_translations" DISABLE TRIGGER ALL;ALTER TABLE "orders" DISABLE TRIGGER ALL;ALTER TABLE "painting_categories" DISABLE TRIGGER ALL;ALTER TABLE "page_services" DISABLE TRIGGER ALL;ALTER TABLE "page_translations" DISABLE TRIGGER ALL;ALTER TABLE "painting_category_translations" DISABLE TRIGGER ALL;ALTER TABLE "page_parts" DISABLE TRIGGER ALL;ALTER TABLE "pages" DISABLE TRIGGER ALL;ALTER TABLE "painting_provenances" DISABLE TRIGGER ALL;ALTER TABLE "painting_prices" DISABLE TRIGGER ALL;ALTER TABLE "painting_technic_translations" DISABLE TRIGGER ALL;ALTER TABLE "painting_technics" DISABLE TRIGGER ALL;ALTER TABLE "painting_type_translations" DISABLE TRIGGER ALL;ALTER TABLE "period_translations" DISABLE TRIGGER ALL;ALTER TABLE "painting_types" DISABLE TRIGGER ALL;ALTER TABLE "paintings" DISABLE TRIGGER ALL;ALTER TABLE "periods" DISABLE TRIGGER ALL
     # -e:1:in `<main>'

 1/1 |========================= 100 ==========================>| Time: 00:00:03 

Finished in 3.41 seconds
1 example, 1 failure

Failed examples:

rspec ./spec/acceptances/provider_services_spec.rb:29 # Provider Services Edit a service
     Screenshot: /home/dougui/rails/lescollectionneurs/tmp/capybara/screenshot_2014-02-20-18-22-55.658.png

Randomized with seed 34053

我在桌子上锁了。 这并不总是相同的表。

当我这样做时，它会更好：

Capybara.reset_sessions!
DatabaseCleaner.clean

规范之前和之后但并不总是有效。 如果我在同一个文件中运行所有规范，我就无法工作。

它在我处理不相关的事情时附加。 它与恶作剧者合作。

这是我的spec_helper文件：

ENV["RAILS_ENV"] ||= 'test'
require 'rubygems'
require File.expand_path("../../config/environment", __FILE__)
require 'rspec/rails'
require 'rspec/autorun'
require 'capybara/rails'
require 'capybara-webkit'
require 'database_cleaner'
require 'capybara/firebug'
require 'capybara-screenshot/rspec'

if defined?(Spring)
  Spring.watch "#{Rails.root}/spec/factories"
else
  require 'shoulda-matchers'
end

Dir[Rails.root.join("spec/support/**/*.rb")].each {|f| require f}

RSpec.configure do |config|
  config.infer_base_class_for_anonymous_controllers = false
  config.use_transactional_fixtures = false
  config.order = "random"

  config.include FactoryGirl::Syntax::Methods
  config.include Warden::Test::Helpers, type: :feature
  config.include FeatureHelpers, type: :feature
  config.include Devise::TestHelpers, type: :controller
  config.include ControllerHelpers, type: :controller
  config.include EmailSpec::Helpers
  config.include EmailSpec::Matchers

  config.before(:suite) do
    DatabaseCleaner.strategy = :transaction
    DatabaseCleaner.clean_with(:truncation)
  end

  config.before(:each) do
    if example.metadata[:js]
      DatabaseCleaner.strategy = :truncation
    else
      DatabaseCleaner.start
    end
  end

  config.after(:each) do
    DatabaseCleaner.clean
    DatabaseCleaner.strategy = :transaction if example.metadata[:js]
  end
end

Capybara.javascript_driver = :webkit

include ActionDispatch::TestProcess
I18n.locale = :fr

Geocoder.configure(:lookup => :test)

Geocoder::Lookup::Test.set_default_stub(
  [
    {
      'latitude'     => 40.7143528,
      'longitude'    => -74.0059731,
      'address'      => 'New York, NY, USA',
      'state'        => 'New York',
      'state_code'   => 'NY',
      'country'      => 'United States',
      'country_code' => 'US'
    }
  ]
)

以下是使用的gem： https ： //github.com/GCorbel/lescollectionneursassocies/blob/master/Gemfile 。

有什么建议？

有关更多详细信息，请查看Github回购： https ： //github.com/GCorbel/lescollectionneursassocies/ 。

Answer 1

发生这种情况是因为您有两个线程，即测试和请求，异步修改数据库。 看起来你正确地在spec_helper中尝试了不同的配置。 我花了相当多的时间来解决同样的问题，并提出了这个问题：

# adapted from https://gist.github.com/moonfly/4950750

require 'database_cleaner'

RSpec.configure do |config|

  config.use_transactional_fixtures = false

  config.before( :suite ) do
    DatabaseCleaner.clean_with :truncation
    DatabaseCleaner.strategy = :transaction
  end

  config.around( :each ) do |spec|
    if spec.metadata[:js]
      # JS => doesn't share connections => can't use transactions
      spec.run
      DatabaseCleaner.clean_with :deletion
    else
      # No JS/Devise => run with Rack::Test => transactions are ok
      DatabaseCleaner.start
      spec.run
      DatabaseCleaner.clean

      # see https://github.com/bmabey/database_cleaner/issues/99
      begin
        ActiveRecord::Base.connection.send :rollback_transaction_records, true
      rescue
      end
    end
  end

end

我把它全部保存在support / database_cleaner_configuration.rb中，这对你也有用，或者你可以简单地替换spec_helper中的内容。 如果这不起作用，请告诉我 - 我还有一些其他的想法，但它们更怪异，如果有效的话，不值得进入，它可能会......

注意：

值得一提的是，Rails 5.1+解决了数据库问题。 Rails团队的Eileen Uchitelle进行了必要的更改以运行确保测试线程，并且Rails服务器可以通过共享数据库连接在同一进程中运行。

Answer 2

当有两个运行测试的线程时，您会遇到死锁。 例如，在终端中打开一个选项卡，然后使用rspec命令运行测试。 立即打开终端中的第二个选项卡，并使用相同的命令在那里运行测试。

所以，我猜你只是在一个选项卡中运行所有测试，并尝试在其他选项卡中使用rspec spec/acceptances/provider_services_spec.rb:31命令运行特定测试。

Answer 3

最可能的原因是必须通过ajax / database clean进行一些查询，在sql查询运行时过早地截断数据库。 其中一种方法是使webkit驱动程序等待，直到ajax请求完成。 在测试助手中添加此方法，并在单击按钮/提交ajax表单后调用它。

    def wait_for_ajax_to_finish
    looping = true
    loop do
      sleep 1
      begin
        count = page.evaluate_script('window.running_ajax_calls').to_i
        looping = false if count == 0
      rescue => e
        if e.message.include? 'HTMLunitCorejsJavascript::Undefined'
          raise "For 'wait for the AJAX call to finish' to work, please include culerity.js after including jQuery."
        else
          raise e
        end
      end
    end
  end

Answer 4

我有不同的测试随机失败（比如500个中的1个测试，每次我运行套件）。

这可能不是最漂亮的解决方案，但我通过在2秒后救援并重试数据库清理器来解决问题，如下所示：

config.after(:each) do |example|
  begin
    DatabaseCleaner.clean
  rescue Exception => e
    # Recover from thread locks and retry the database clean after a slight delay
    sleep 2
    DatabaseCleaner.clean
  end
end