blocks|key|2855439|text|Crontab很可能是作为一个没有访问chromedriver目录/文件的权限的用户运行的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2855440|看看如何以特定用户的身份运行crontab的答案在这里。|offset|length|2855441|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/questions/8475694/how-to-specify-in-crontab-by-what-user-to-run-script^0|0|M|5|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|O|8|@]|9|@$D|P|E|Q|1|R]]|A|$]]|$1|F|3|-4|5|6|7|S|8|@]|9|@]|A|$]]]|G|$H|$5|I|J|K|A|$L|M]]]]

Crontab is likely running as a user that doesn't have permission to access the chromedriver directory/file.

Take a look at the <a href="https://stackoverflow.com/questions/8475694/how-to-specify-in-crontab-by-what-user-to-run-script">answers here</a> on how to run crontab as a specific user.

blocks|key|2855482|text|尝试从cron启动浏览器最明显的问题是，即使您的计算机上运行了X，也不会为从crontab运行的进程设置DISPLAY环境变量，因此从crontab启动浏览器将失败。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|2855483|解决方案的范围从琐碎到超级复杂。一个简单的解决方案是，如果没有X运行，脚本就不会运行，并手动将DISPLAY设置为:0，这是Ubuntu启动的默认X服务器的默认显示号。|2855484|例如，如果我将此命令放在command行的crontab列中，则Chrome启动时没有问题：|2855485|DISPLAY=:0+google-chrome|code-block|syntax|javascript|2855486|特定于用户的crontab文件中的完整行如下所示：|2855487|0+*+*+*+*++DISPLAY=:0+google-chrome|2855488|如果您想运行一个通过selenium启动chrome的python脚本，那么该行将改为如下所示：|2855489|0+*+*+*+*++DISPLAY=:0+python+my_script.py|2855490|命令字符串仅作为-原样发送到shell，因此在最后一个示例中，字符串DISPLAY=:0+python+my_script.py将被传递给shell。将命令开始时立即给出的变量赋值解释为设置环境变量是常见的shell语法。(+dash和bash的情况肯定是这样，其中之一很可能是大多数安装中默认的shell。)因此，shell解释的命令将环境变量DISPLAY设置为值:0，然后运行python+my_script.py。因为python从启动它的shell继承了它的环境，所以变量DISPLAY也是它的:0。|2855491|设置DISPLAY=:0，如我前面所示，只为下面的命令设置变量。对于crontab执行的所有命令，还可以将DISPLAY设置为:0。例如，在以下特定于用户的crontab中：|2855492|DISPLAY=:0

30+*+*+*+*++google-chrome
0++*+*+*+*++python+my_script.py|2855493|行DISPLAY=:0设置环境变量DISPLAY，用于执行google-chrome和python+my_script.py。|2855494|entityMap^0|3|4|12|7|1G|7|1V|7|0|1B|7|1L|2|0|C|7|L|7|0|0|0|0|0|0|Y|U|35|4|3A|4|4T|7|54|2|5B|J|5X|6|6P|7|70|2|0|2|A|1H|7|1R|2|0|0|1|A|H|7|T|D|17|J|0^^$0|@$1|2|3|4|5|6|7|16|8|@$9|17|A|18|B|C]|$9|19|A|1A|B|C]|$9|1B|A|1C|B|C]|$9|1D|A|1E|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|1F|8|@$9|1G|A|1H|B|C]|$9|1I|A|1J|B|C]]|D|@]|E|$]]|$1|H|3|I|5|6|7|1K|8|@$9|1L|A|1M|B|C]|$9|1N|A|1O|B|C]]|D|@]|E|$]]|$1|J|3|K|5|L|7|1P|8|@]|D|@]|E|$M|N]]|$1|O|3|P|5|6|7|1Q|8|@]|D|@]|E|$]]|$1|Q|3|R|5|L|7|1R|8|@]|D|@]|E|$M|N]]|$1|S|3|T|5|6|7|1S|8|@]|D|@]|E|$]]|$1|U|3|V|5|L|7|1T|8|@]|D|@]|E|$M|N]]|$1|W|3|X|5|6|7|1U|8|@$9|1V|A|1W|B|C]|$9|1X|A|1Y|B|C]|$9|1Z|A|20|B|C]|$9|21|A|22|B|C]|$9|23|A|24|B|C]|$9|25|A|26|B|C]|$9|27|A|28|B|C]|$9|29|A|2A|B|C]|$9|2B|A|2C|B|C]]|D|@]|E|$]]|$1|Y|3|Z|5|6|7|2D|8|@$9|2E|A|2F|B|C]|$9|2G|A|2H|B|C]|$9|2I|A|2J|B|C]]|D|@]|E|$]]|$1|10|3|11|5|L|7|2K|8|@]|D|@]|E|$M|N]]|$1|12|3|13|5|6|7|2L|8|@$9|2M|A|2N|B|C]|$9|2O|A|2P|B|C]|$9|2Q|A|2R|B|C]|$9|2S|A|2T|B|C]]|D|@]|E|$]]|$1|14|3|-4|5|6|7|2U|8|@]|D|@]|E|$]]]|15|$]]

The most evident problem with trying to launch a browser from <code>cron</code> is that even if you have X running on your machine, the <code>DISPLAY</code> environment variable is not set for processes running from your <code>crontab</code> so launching a browser from there will fail.

Solutions range from the trivial to the super sophisticated. A trivial solution would be to accept that your script won't run if there is no X running and manually set <code>DISPLAY</code> to <code>:0</code>, which is the default display number for the default X server that Ubuntu starts.

For instance, if I put this command in the <code>command</code> column of a <code>crontab</code> line, Chrome starts without issue:

<pre><code>DISPLAY=:0 google-chrome
</code></pre>

The complete line in the a user-specific crontab file would be something like:

<pre><code>0 * * * * DISPLAY=:0 google-chrome
</code></pre>

If you want to run a python script that starts chrome through selenium, the line would instead look like:

<pre><code>0 * * * * DISPLAY=:0 python my_script.py
</code></pre>

The command string is just sent as-is to the shell so in the last example the string <code>DISPLAY=:0 python my_script.py</code> would be just passed to the shell. It is common shell syntax to interpret a variable assignment given immediately at the start of the command as setting an environment variable. (It is certainly the case for <code>dash</code> and <code>bash</code>, one of which is likely to be the default shell in most installations.) So the command that the shell interprets sets the environment variable <code>DISPLAY</code> to the value <code>:0</code> and then runs <code>python my_script.py</code>. Since <code>python</code> inherits its environment from the shell that started it, the variable <code>DISPLAY</code> is <code>:0</code> for it too. 

Setting <code>DISPLAY=:0</code> like I show above sets the variable only for the command that follows. It is also possible to set <code>DISPLAY</code> to <code>:0</code> for all commands executed by the crontab. For instance in the following user-specific crontab:

<pre><code>DISPLAY=:0

30 * * * * google-chrome
0 * * * * python my_script.py
</code></pre>

the line <code>DISPLAY=:0</code> sets the environment variable <code>DISPLAY</code> both for the execution of <code>google-chrome</code> and <code>python my_script.py</code>

blocks|key|252294|text|selenium+web驱动程序需要X会话来运行脚本。Cron脚本通常使用out+X会话运行。在cron脚本中添加X会话。如下：*+11+***导出DISPLAY=:0；您的script.py|type|unstyled|depth|inlineStyleRanges|entityRanges|data|252295|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

selenium web drivers needs X session for running script. Cron scripts normally runs with out X session. Add X session in your cron script. Like as follows:
* 11 * * * export DISPLAY=:0; your script.py

blocks|key|2855556|text|在MacOS+Catalina上，只有这个命令对我有效。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2855557|*+*+*+*+*+export+DISPLAY=:0+&&+export+PATH=$PATH:/usr/local/bin+&&+/usr/bin/python3+~/Documents/Scripts/my_script.py|code-block|syntax|javascript|2855558|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

on MacOS Catalina only this command worked for me

<pre class="lang-sh prettyprint-override"><code>* * * * * export DISPLAY=:0 &amp;&amp; export PATH=$PATH:/usr/local/bin &amp;&amp; /usr/bin/python3 ~/Documents/Scripts/my_script.py
</code></pre>

blocks|key|1858633|text|使用pyvirtualdisplay和Xvfb为您管理窗口会话(最初来自这个答案)|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1858634|背景：|style|BOLD|1858635|就我而言，公认的答案是行不通的。|1858636|解决方案：|1858637|安装PyVirtualDisplay和Xvfb|ordered-list-item|1858638|pip3+install+pyvirtualdisplay
sudo+apt-get+install+xvfb|code-block|syntax|javascript|1858639|在.py脚本中分配窗口处理程序|CODE|1858640|from+selenium+import+webdriver
from+selenium.webdriver.common.keys+import+Keys
from+pyvirtualdisplay+import+Display
import+time

#+Display+creates+a+virtual+frame+buffer+and+manages+it+for+you
with+Display(visible=False,+size=(1200,+1500)):
++++driver+=+webdriver.Firefox()
++++driver.get("https://website-target.com")

++++time.sleep(1)

++++print(driver.current_url)+#+check+connection

++++time.sleep(1)

++++print(driver.current_url)

++++driver.close()|1858641|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/ponty/pyvirtualdisplay/tree/2.1|1|https://stackoverflow.com/a/45550850/11671779^0|2|L|0|10|4|1|0|0|3|0|0|0|5|0|0|0|1|3|0|0^^$0|@$1|2|3|4|5|6|7|18|8|@]|9|@$A|19|B|1A|1|1B]|$A|1C|B|1D|1|1E]]|C|$]]|$1|D|3|E|5|6|7|1F|8|@$A|1G|B|1H|F|G]]|9|@]|C|$]]|$1|H|3|I|5|6|7|1I|8|@]|9|@]|C|$]]|$1|J|3|K|5|6|7|1J|8|@$A|1K|B|1L|F|G]]|9|@]|C|$]]|$1|L|3|M|5|N|7|1M|8|@]|9|@]|C|$]]|$1|O|3|P|5|Q|7|1N|8|@]|9|@]|C|$R|S]]|$1|T|3|U|5|N|7|1O|8|@$A|1P|B|1Q|F|V]]|9|@]|C|$]]|$1|W|3|X|5|Q|7|1R|8|@]|9|@]|C|$R|S]]|$1|Y|3|-4|5|6|7|1S|8|@]|9|@]|C|$]]]|Z|$10|$5|11|12|13|C|$14|15]]|16|$5|11|12|13|C|$14|17]]]]

Use <a href="https://github.com/ponty/pyvirtualdisplay/tree/2.1" rel="nofollow noreferrer">pyvirtualdisplay and Xvfb</a> to manage your window session for you (originally from <a href="https://stackoverflow.com/a/45550850/11671779">this answer</a>)
Background:
In my case, the accepted answer is not working.
Solution:
<ol>
<li>Install PyVirtualDisplay and Xvfb</li>
</ol>
<pre class="lang-sh prettyprint-override"><code>pip3 install pyvirtualdisplay
sudo apt-get install xvfb
</code></pre>
<ol start="2">
<li>Assign window handler in your <code>.py</code> script</li>
</ol>
<pre class="lang-py prettyprint-override"><code>from selenium import webdriver
from selenium.webdriver.common.keys import Keys
from pyvirtualdisplay import Display
import time

# Display creates a virtual frame buffer and manages it for you
with Display(visible=False, size=(1200, 1500)):
 driver = webdriver.Firefox()
 driver.get(&quot;https://website-target.com&quot;)

 time.sleep(1)

 print(driver.current_url) # check connection

 time.sleep(1)

 print(driver.current_url)

 driver.close()

</code></pre>

I have a python script that calls chrome via selenium with the next line.

<pre><code> ff = webdriver.Chrome('/home/user01/webScraping/CollectAndGo/chromedriver')
</code></pre>

The python script is called from a shell script.

<pre><code>python /home/user01/webScraping/CollectAndGo/cgcom.py &gt; /home/user01/webScraping/CollectAndGo/cgcom.log 2&gt;&amp;1
</code></pre>

When I run the script from the terminal or just executing the .sh file it works perfectly but when I schedule a crontab job it fail with the next error.

<pre><code> raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.WebDriverException: Message: u'unknown error: Chrome failed to start: exited abnormally\n (Driver info: chromedriver=2.9.248304,platform=Linux 3.5.0-36-generic x86_64)' 
</code></pre>

The error is related to the first line of code of this question. Does anybody know why this could be happening?

run selenium with crontab (python)

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我有一个python脚本，它使用下一行selenium调用chrome。 ff = webdriver.Chrome('/home/user01/webScraping/CollectAndGo/chromedriver')python脚本是从shell脚本调用的。python /home/user01/webScra...

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