Class: ChromeDiff::Session

Inherits:
Object
  • Object
show all
Defined in:
lib/chrome_diff/session.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(width: nil, height: nil, timeout: nil, debug: false) ⇒ Session

Returns a new instance of Session.



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# File 'lib/chrome_diff/session.rb', line 28

def initialize(width: nil, height: nil, timeout: nil, debug: false)
  @width = width || ChromeDiff::DEFAULT_OPTIONS[:width]
  @height = height || ChromeDiff::DEFAULT_OPTIONS[:height]
  @timeout = timeout || ChromeDiff::DEFAULT_OPTIONS[:timeout]
  @debug = debug
  options = {
    window_size: [@width, @height],
    timeout: @timeout,
    browser_options: {
      "device-scale-factor" => 1,
      "force-device-scale-factor" => nil,
    },
  }
  if @debug
    options[:logger] = STDOUT
    options[:headless] = false
  end

  @browser = Ferrum::Browser.new(options)
  @browser.resize(width: @width, height: @height)
end

Instance Attribute Details

#browser ⇒ Object (readonly)

Returns the value of attribute browser.



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# File 'lib/chrome_diff/session.rb', line 26

def browser
  @browser
end

Instance Method Details

#compare(from_url:, to_url:, output:, threshold: nil, full_screenshot: nil) ⇒ Object 



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# File 'lib/chrome_diff/session.rb', line 50

def compare(from_url:, to_url:, output:, threshold: nil, full_screenshot: nil)
  threshold ||= ChromeDiff::DEFAULT_OPTIONS[:threshold]
  result = nil
  Dir.mktmpdir do |tmpdir|
    from_file = File.join(tmpdir, "from.png")
    to_file = File.join(tmpdir, "to.png")
    diff_file = File.join(tmpdir, "diff.png")

    screenshot(from_url, from_file, full_screenshot)
    screenshot(to_url, to_file, full_screenshot)

    _stdout, stderr, status =  Open3.capture3("compare", "-metric", "AE", from_file, to_file, diff_file)
    result = CompareStatus.new(status, stderr, @width, @height, threshold)

    File.rename(diff_file, output) if output
  end

  result
end

#screenshot(url, file, full) ⇒ Object 



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# File 'lib/chrome_diff/session.rb', line 70

def screenshot(url, file, full)
  @browser.goto(url)
  wait_complete
  @browser.resize(width: @width, height: @height)
  @browser.screenshot(path: file, full: full)
end

#wait_complete ⇒ Object 



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# File 'lib/chrome_diff/session.rb', line 77

def wait_complete
  @browser.network.wait_for_idle
  Timeout.timeout(@timeout) do
    until @browser.page.evaluate('document.readyState') == "complete"
      sleep 0.1
    end
  end
end