Resolve "Allow QA tests to run with `CHROME_HEADLESS=false`"

qa/qa.rb

@@ -10,6 +10,7 @@ module QA
     autoload :Namespace, 'qa/runtime/namespace'
     autoload :Scenario, 'qa/runtime/scenario'
     autoload :Browser, 'qa/runtime/browser'
+    autoload :Env, 'qa/runtime/env'
   end
   ##

qa/qa/runtime/browser.rb

@@ -38,22 +38,49 @@ module QA
         Capybara.register_driver :chrome do |app|
           capabilities = Selenium::WebDriver::Remote::Capabilities.chrome(
-            'chromeOptions' => {
-              'args' => %w[headless no-sandbox disable-gpu window-size=1280,1680]
+            # This enables access to logs with `page.driver.manage.get_log(:browser)`
+            loggingPrefs: {
+              browser: "ALL",
+              client: "ALL",
+              driver: "ALL",
+              server: "ALL"
             }
           )
-          Capybara::Selenium::Driver
-            .new(app, browser: :chrome, desired_capabilities: capabilities)
-        end
-        Capybara::Screenshot.register_driver(:chrome) do |driver, path|
-          driver.browser.save_screenshot(path)
+          options = Selenium::WebDriver::Chrome::Options.new
+          options.add_argument("window-size=1240,1680")
+          # Chrome won't work properly in a Docker container in sandbox mode
+          options.add_argument("no-sandbox")
+
+          # Run headless by default unless CHROME_HEADLESS is false
+          if QA::Runtime::Env.chrome_headless?
+            options.add_argument("headless")
+
+            # Chrome documentation says this flag is needed for now
+            # https://developers.google.com/web/updates/2017/04/headless-chrome#cli
+            options.add_argument("disable-gpu")
+          end
+
+          # Disable /dev/shm use in CI. See https://gitlab.com/gitlab-org/gitlab-ee/issues/4252
+          options.add_argument("disable-dev-shm-usage") if QA::Runtime::Env.running_in_ci?
+
+          Capybara::Selenium::Driver.new(
+            app,
+            browser: :chrome,
+            desired_capabilities: capabilities,
+            options: options
+          )
         end
         # Keep only the screenshots generated from the last failing test suite
         Capybara::Screenshot.prune_strategy = :keep_last_run
+        # From https://github.com/mattheworiordan/capybara-screenshot/issues/84#issuecomment-41219326
+        Capybara::Screenshot.register_driver(:chrome) do |driver, path|
+          driver.browser.save_screenshot(path)
+        end
+
         Capybara.configure do |config|
           config.default_driver = :chrome
           config.javascript_driver = :chrome

qa/qa/runtime/env.rb

+module QA
+  module Runtime
+    module Env
+      extend self
+
+      def chrome_headless?
+        (ENV['CHROME_HEADLESS'] =~ /^(false|no|0)$/i) != 0
+      end
+
+      def running_in_ci?
+        ENV['CI'] || ENV['CI_SERVER']
+      end
+    end
+  end
+end

qa/spec/runtime/env_spec.rb

+describe QA::Runtime::Env do
+  before do
+    allow(ENV).to receive(:[]).and_call_original
+  end
+
+  describe '.chrome_headless?' do
+    context 'when there is an env variable set' do
+      it 'returns false when falsey values specified' do
+        stub_env('CHROME_HEADLESS', 'false')
+        expect(described_class.chrome_headless?).to be_falsey
+
+        stub_env('CHROME_HEADLESS', 'no')
+        expect(described_class.chrome_headless?).to be_falsey
+
+        stub_env('CHROME_HEADLESS', '0')
+        expect(described_class.chrome_headless?).to be_falsey
+      end
+
+      it 'returns true when anything else specified' do
+        stub_env('CHROME_HEADLESS', 'true')
+        expect(described_class.chrome_headless?).to be_truthy
+
+        stub_env('CHROME_HEADLESS', '1')
+        expect(described_class.chrome_headless?).to be_truthy
+
+        stub_env('CHROME_HEADLESS', 'anything')
+        expect(described_class.chrome_headless?).to be_truthy
+      end
+    end
+
+    context 'when there is no env variable set' do
+      it 'returns the default, true' do
+        stub_env('CHROME_HEADLESS', nil)
+        expect(described_class.chrome_headless?).to be_truthy
+      end
+    end
+  end
+
+  describe '.running_in_ci?' do
+    context 'when there is an env variable set' do
+      it 'returns true if CI' do
+        stub_env('CI', 'anything')
+        expect(described_class.running_in_ci?).to be_truthy
+      end
+
+      it 'returns true if CI_SERVER' do
+        stub_env('CI_SERVER', 'anything')
+        expect(described_class.running_in_ci?).to be_truthy
+      end
+    end
+
+    context 'when there is no env variable set' do
+      it 'returns true' do
+        stub_env('CI', nil)
+        stub_env('CI_SERVER', nil)
+        expect(described_class.running_in_ci?).to be_falsey
+      end
+    end
+  end
+
+  def stub_env(name, value)
+    allow(ENV).to receive(:[]).with(name).and_return(value)
+  end
+end