我正在研究屏幕截图自动化。特别是，我正在努力实现以下目标：
- 提示用户提供网站不同页面的链接 X
- 提示用户输入类名 Y
- 我应该能够访问网站 X 登录页面，提供登录详细信息（假设它们已知），单击“提交”按钮，这应该将我重定向到“主页”页面
- 然后，我查看用户提供的链接列表，访问每个页面并截取具有 Y 类（或整个页面）的所有元素的屏幕截图
- 将它们保存在当前目录中
请点击链接查看视觉表现 https://i.stack.imgur.com/qLE40.png
我想在 Ruby 中实现以下解决方案（但我也愿意接受任何其他建议）：
1) 截取网站 X 上整个可滚动页面的屏幕截图 2) 找到 Y 类的元素，特别是它在页面上的位置、宽度和高度。 3）裁剪完整屏幕截图，以便只显示所需的元素
问题如下：
我无法截取整个页面的屏幕截图，我只能截取屏幕可见区域的屏幕截图。
这是我尝试过的以及相应的问题：
解决方案 1（Ruby - 常规）：
require 'selenium-webdriver'
driver = Selenium::WebDriver.for :firefox #:chrome
driver.navigate.to "https://some_very-very_long_page_on_website_X"
driver.manage.window.maximize # <- works for firefox only
driver.save_screenshot('picture1.png')
# Problem: it captures only the viewable area,
# not an entire page
解决方案 2（Ruby - 调整窗口大小）：
require 'selenium-webdriver'
driver = Selenium::WebDriver.for :firefox #:chrome
driver.navigate.to 'https://some_very-very_long_page_on_website_X'
width = driver.execute_script("return Math.max(document.body.scrollWidth,document.body.offsetWidth,document.documentElement.clientWidth,document.documentElement.scrollWidth,document.documentElement.offsetWidth);")
height = driver.execute_script("return Math.max(document.body.scrollHeight,document.body.offsetHeight,document.documentElement.clientHeight,document.documentElement.scrollHeight,document.documentElement.offsetHeight);")
driver.manage.window.resize_to(width, height) # <- resizes the window
driver.manage.window.full_screen # <- works, but in chrome throws:
# full_screen': undefined method `full_screen_window'
picture = driver.screenshot_as(:png)
File.open('picture2.png', 'w+') do |fh|
fh.write picture
end
driver.quit
# Resizes the window only to the viewable area, as a result,
# it captures the viewable area only
解决方案 3（红宝石 - watir gem）：
require 'watir'
b = Watir::Browser.new
b.goto 'https://some_very-very_long_page_on_website_X'
b.screenshot.save("picture.png")
# Issues: does not capture the entire page
解决方案 4（Ruby - 单元素捕获）
require "selenium-webdriver"
driver = Selenium::WebDriver.for :chrome
driver.get'https://some_very-very_long_page_on_website_X'
driver.manage.window.maximize
driver.execute_script("document.getElementById('some_id').scrollIntoView();")
driver.save_screenshot "picture3.png"
# Problem: captures the element, which I need, but only if its size is less than
# the viewable area
解决方案 5（Ruby - 缩放）
require "selenium-webdriver"
driver = Selenium::WebDriver.for :firefox
driver.get 'https://some_very-very_long_page_on_website_X'
driver.manage.window.maximize
driver.execute_script("document.body.style.transform = 'scale(0.5)'")
#driver.execute_script("document.body.style.zoom = '50%'") <-- transform works better than zoom
driver.save_screenshot "picture3.png"
#Issues: works, but not for very long pages, in addition it may change the layout
# (some elements may start to overlap each other)
# Also I am not sure how to calculate the value of the parameter for scale
# for very long pages
解决方案 6 -（Ruby - 无头 Chrome 调整大小）
require "selenium-webdriver"
options = Selenium::WebDriver::Chrome::Options.new
options.add_argument('--headless')
driver = Selenium::WebDriver.for :chrome, options: options
driver.get "https://some_very-very_long_page_on_website_X"
width = driver.execute_script("return Math.max(document.body.scrollWidth,document.body.offsetWidth,document.documentElement.clientWidth,document.documentElement.scrollWidth,document.documentElement.offsetWidth);")
height = driver.execute_script("return Math.max(document.body.scrollHeight,document.body.offsetHeight,document.documentElement.clientHeight,document.documentElement.scrollHeight,document.documentElement.offsetHeight);")
driver.manage.window.resize_to(width+2000, height+2000) # <-- if I do not have +2000, page looks squished
# the greater the number, the greater the quality
# but also the more white space is around the page
# and the picture is heavier
driver.manage.window.maximize
sleep 5 # <--- required waiting for page loading
driver.save_screenshot "full.png"
# One of the best approaches, but it is not clear to me how to calculate
# the parameters for resize_to
工具/技术：
- 硒-webdriver (3.12.0)
- Chrome 驱动程序 2.40
