ruby selenium web driver - 获取谷歌知识图内容

Question

我正在使用 ruby​​ selenium 网络驱动程序并尝试从<div class="xpdopen"> 中的第一个谷歌搜索结果页面上的搜索结果中获取位于右上角的谷歌知识图的内容

@driver = Selenium::WebDriver.for :phantomjs
@driver.manage.timeouts.implicit_wait = 10
@driver.get "http://google.com"
element = @driver.find_element :name => "q"
element.send_keys "BMW"
element.submit
content = @driver.find_element(:class, 'xpdopen')

但是selenium找不到这个元素会报错

#<Selenium::WebDriver::Error::NoSuchElementError: {"errorMessage":"Unable to find element with class name 'xpdopen'"

当我在 chrome js 控制台$('.xpdopen') 中尝试时，它立即找到了这个元素

我也试过

@driver.execute_script("return document.getElementsByClassName('xpdopen');")

但是找不到这个元素

我还在页面源中绑定了@driver.page_source 和<div class="xpdopen">，但我可以在 chrome 控制台中看到它。为什么？

我怎样才能用硒获得这个元素？

这是我从 pry 中得到的结果：

[21] pry(main)> @driver = Selenium::WebDriver.for :phantomjs
=> #<Selenium::WebDriver::Driver:0x..f822d288ec7f0a708 browser=:phantomjs>
[22] pry(main)> @driver.manage.timeouts.implicit_wait = 10    
=> 10
[23] pry(main)> @driver.get "http://google.com"    
=> {}
[24] pry(main)> element = @driver.find_element :name => "q"    
=> #<Selenium::WebDriver::Element:0x..f389f4a8876f601e id=":wdc:1434526425103">
[25] pry(main)> element.send_keys "BMW"    
=> nil
[26] pry(main)> element.submit    
=> {}
[27] pry(main)> sleep 10    
=> 10
[28] pry(main)> content = @driver.find_element(:xpath, '//*[@id="rhs_block"]/ol/li/div[1]/div')    
Selenium::WebDriver::Error::NoSuchElementError: {"errorMessage":"Unable to find element with xpath '//*[@id=\"rhs_block\"]/ol/li/div[1]/div'","request":{"headers":{"Accept":"application/json","Accept-Encoding":"gzip;q=1.0,deflate;q=0.6,identity;q=0.3","Connection":"close","Content-Length":"67","Content-Type":"application/json; charset=utf-8","Host":"127.0.0.1:8929","User-Agent":"Ruby"},"httpVersion":"1.1","method":"POST","post":"{\"using\":\"xpath\",\"value\":\"//*[@id=\\\"rhs_block\\\"]/ol/li/div[1]/div\"}","url":"/element","urlParsed":{"anchor":"","query":"","file":"element","directory":"/","path":"/element","relative":"/element","port":"","host":"","password":"","user":"","userInfo":"","authority":"","protocol":"","source":"/element","queryKey":{},"chunks":["element"]},"urlOriginal":"/session/2f3cf350-14c3-11e5-9f8e-4173e8049986/element"}} (org.openqa.selenium.NoSuchElementException)

和

[29] pry(main)> content = @driver.find_element(:css, "#rhs_block > ol > li > div.kp-blk._Jw._Rqb._RJe > .xpdopen")
Selenium::WebDriver::Error::NoSuchElementError: {"errorMessage":"Unable to find element with css selector '#rhs_block > ol > li > div.kp-blk._Jw._Rqb._RJe > .xpdopen'","request":{"headers":{"Accept":"application/json","Accept-Encoding":"gzip;q=1.0,deflate;q=0.6,identity;q=0.3","Connection":"close","Content-Length":"113","Content-Type":"application/json; charset=utf-8","Host":"127.0.0.1:8929","User-Agent":"Ruby"},"httpVersion":"1.1","method":"POST","post":"{\"using\":\"css selector\",\"value\":\"#rhs_block \\u003e ol \\u003e li \\u003e div.kp-blk._Jw._Rqb._RJe \\u003e .xpdopen\"}","url":"/element","urlParsed":{"anchor":"","query":"","file":"element","directory":"/","path":"/element","relative":"/element","port":"","host":"","password":"","user":"","userInfo":"","authority":"","protocol":"","source":"/element","queryKey":{},"chunks":["element"]},"urlOriginal":"/session/2f3cf350-14c3-11e5-9f8e-4173e8049986/element"}} (org.openqa.selenium.NoSuchElementException)

只是为了证明它可以在同一页面上毫无问题地找到其他元素：

[30] pry(main)> results = @driver.find_elements(:xpath, "//p/a") 
=> [#<Selenium::WebDriver::Element:0x6f6a74631e2b7010 id=":wdc:1434527087873">,
 #<Selenium::WebDriver::Element:0x7b6d276448081688 id=":wdc:1434527087874">,
 #<Selenium::WebDriver::Element:0x..f9504a4171b03970a id=":wdc:1434527087875">,
 #<Selenium::WebDriver::Element:0x..fa6e0158aa8d24e2a id=":wdc:1434527087876">,
 #<Selenium::WebDriver::Element:0x327bf842e4399368 id=":wdc:1434527087877">,
 #<Selenium::WebDriver::Element:0x..fae292d7ca211ab32 id=":wdc:1434527087878">,
 #<Selenium::WebDriver::Element:0x129a58eb5ed6ee9c id=":wdc:1434527087879">,
 #<Selenium::WebDriver::Element:0x46ef3b45800e63e0 id=":wdc:1434527087880">,
 #<Selenium::WebDriver::Element:0x26bfb47f8ad498ea id=":wdc:1434527087881">,
 #<Selenium::WebDriver::Element:0x..f03756c2924a2974 id=":wdc:1434527087882">,
 #<Selenium::WebDriver::Element:0xfba93aab4b32af8 id=":wdc:1434527087883">]

我用截图发现phantomjs没有显示（没有内容）知识图谱

phantomjs 的截图

来自 Firefox 的屏幕截图

为什么phantomjs没有内容知识图谱？

Answer 1

显然 css 自己不知道在哪里可以找到 xpdopen 类，你必须给出元素的整个路径：

Xpath：

content = @driver.find_element(:xpath, "//*[@id="rhs_block"]/ol/li/div[1]/div")

CSS：

content = @driver.find_element(:css, "#rhs_block > ol > li > div.kp-blk._Jw._Rqb._RJe > .xpdopen")