Question

我正在使用python-selenium和Chrome 59并试图自动化一个简单的下载序列。当我正常启动浏览器时，下载工作正常，但是当我在无头模式下这样做时，下载不起作用。

# Headless implementation
from selenium import webdriver

chromeOptions = webdriver.ChromeOptions()
chromeOptions.add_argument("headless")

driver = webdriver.Chrome(chrome_options=chromeOptions)

driver.get('https://www.mockaroo.com/')
driver.find_element_by_id('download').click()
# ^^^ Download doesn't start

# Normal Mode
from selenium import webdriver

driver = webdriver.Chrome()

driver.get('https://www.mockaroo.com/')
driver.find_element_by_id('download').click()
# ^^^ Download works normally

我甚至尝试过添加默认路径：

prefs = {"download.default_directory" : "/Users/Chetan/Desktop/"}
chromeOptions.add_argument("headless")
chromeOptions.add_experimental_option("prefs",prefs)

添加默认路径在正常实现中有效，但无头版本中仍然存在同样的问题。

如何在无头模式下开始下载？

Answer 1

是的，这是一个“功能”，为了安全。如前所述，这是错误讨论：https://bugs.chromium.org/p/chromium/issues/detail?id=696481

在Chrome版本62.0.3196.0或更高版本中添加了支持以启用下载。

这是一个python实现。我不得不将命令添加到chromedriver命令。我将尝试提交PR，以便将来包含在库中。

def enable_download_in_headless_chrome(self, driver, download_dir):
    # add missing support for chrome "send_command"  to selenium webdriver
    driver.command_executor._commands["send_command"] = ("POST", '/session/$sessionId/chromium/send_command')

    params = {'cmd': 'Page.setDownloadBehavior', 'params': {'behavior': 'allow', 'downloadPath': download_dir}}
    command_result = driver.execute("send_command", params)

这里有一个小回复来演示如何使用它： https://github.com/shawnbutton/PythonHeadlessChrome

Answer 2

这是Chrome的一项功能，可防止软件将文件下载到您的计算机。但有一个解决方法。 Read more about it here

你需要做的是通过DevTools启用它，像这样：

async function setDownload () {
  const client = await CDP({tab: 'ws://localhost:9222/devtools/browser'});
  const info =  await client.send('Browser.setDownloadBehavior', {behavior : "allow", downloadPath: "/tmp/"});
  await client.close();
}

这是一个人在上述主题中给出的解决方案。 Here is his comment

Answer 3

这是一个基于Shawn Button's answer的Python实用示例。我已经使用 Chromium 68.0.3440.75 和 chromedriver 2.38

对此进行了测试

from selenium import webdriver
from selenium.webdriver.chrome.options import Options

chrome_options = Options()
chrome_options.add_experimental_option("prefs", {
  "download.default_directory": "/path/to/download/dir",
  "download.prompt_for_download": False,
})

chrome_options.add_argument("--headless")
driver = webdriver.Chrome(chrome_options=chrome_options)

driver.command_executor._commands["send_command"] = ("POST", '/session/$sessionId/chromium/send_command')
params = {'cmd': 'Page.setDownloadBehavior', 'params': {'behavior': 'allow', 'downloadPath': "/path/to/download/dir"}}
command_result = driver.execute("send_command", params)

driver.get('http://download-page.url/')
driver.find_element_by_css_selector("#download_link").click()

Answer 4

也许你处理的网站会为浏览器返回不同的HTML页面，这意味着你想要的XPath或Id在无头浏览器中可能会有所不同。尝试在无头浏览器中下载pageSource并将其打开为HTML页面以查看所需的Id或XPath。您可以将其视为c＃示例How to hide FirefoxDriver (using Selenium) without findElement function error in PhantomDriver?。

Answer 5

更新的 Python 解决方案 - 2021 年 3 月 4 日在 chromedriver v88 和 v89 上测试

这将允许您在无头模式下点击下载文件。

    from selenium import webdriver
    from selenium.webdriver.common.keys import Keys
    from selenium.webdriver.chrome.options import Options

    # Instantiate headless driver
    chrome_options = Options()

    # Windows path
    chromedriver_location = 'C:\\path\\to\\chromedriver_win32\\chromedriver.exe'
    # Mac path. May have to allow chromedriver developer in os system prefs
    '/Users/path/to/chromedriver'

    chrome_options.add_argument("--headless")
    chrome_options.add_argument("--no-sandbox")
    chrome_options.add_argument("--disable-dev-shm-usage")
    
    chrome_prefs = {"download.default_directory": r"C:\path\to\Downloads"} # (windows)
    chrome_options.experimental_options["prefs"] = chrome_prefs

    driver = webdriver.Chrome(chromedriver_location,options=chrome_options)

    # Download your file
    driver.get('https://www.mockaroo.com/')
    driver.find_element_by_id('download').click()

Answer 6

通常看到相同的东西只是用另一种语言编写是多余的，但是因为这个问题使我发疯，所以我希望我能免于痛苦……所以这里是Shawn Button's answer的C＃版本（使用无头chrome = 71.0.3578.98，chromedriver = 2.45.615279，平台= Linux 4.9.125-linuxkit x86_64）进行了测试）：

            var enableDownloadCommandParameters = new Dictionary<string, object>
            {
                { "behavior", "allow" },
                { "downloadPath", downloadDirectoryPath }
            };
            var result = ((OpenQA.Selenium.Chrome.ChromeDriver)driver).ExecuteChromeCommandWithResult("Page.setDownloadBehavior", enableDownloadCommandParameters);

Answer 7

使用selenium-cucumber-js / selenium-webdriver的JavaScript的完整示例：

const chromedriver = require('chromedriver');
const selenium = require('selenium-webdriver');
const command = require('selenium-webdriver/lib/command');
const chrome = require('selenium-webdriver/chrome');

module.exports = function() {

  const chromeOptions = new chrome.Options()
    .addArguments('--no-sandbox', '--headless', '--start-maximized', '--ignore-certificate-errors')
    .setUserPreferences({
      'profile.default_content_settings.popups': 0, // disable download file dialog
      'download.default_directory': '/tmp/downloads', // default file download location
      "download.prompt_for_download": false,
      'download.directory_upgrade': true,
      'safebrowsing.enabled': false,
      'plugins.always_open_pdf_externally': true,
      'plugins.plugins_disabled': ["Chrome PDF Viewer"]
    })
    .windowSize({width: 1600, height: 1200});

  const driver = new selenium.Builder()
    .withCapabilities({
      browserName: 'chrome',
      javascriptEnabled: true,
      acceptSslCerts: true,
      path: chromedriver.path
    })
    .setChromeOptions(chromeOptions)
    .build();

  driver.manage().window().maximize();

  driver.getSession()
    .then(session => {
      const cmd = new command.Command("SEND_COMMAND")
        .setParameter("cmd", "Page.setDownloadBehavior")
        .setParameter("params", {'behavior': 'allow', 'downloadPath': '/tmp/downloads'});
      driver.getExecutor().defineCommand("SEND_COMMAND", "POST", `/session/${session.getId()}/chromium/send_command`);
      return driver.execute(cmd);
    });

  return driver;
};

关键部分是：

  driver.getSession()
    .then(session => {
      const cmd = new command.Command("SEND_COMMAND")
        .setParameter("cmd", "Page.setDownloadBehavior")
        .setParameter("params", {'behavior': 'allow', 'downloadPath': '/tmp/downloads'});
      driver.getExecutor().defineCommand("SEND_COMMAND", "POST", `/session/${session.getId()}/chromium/send_command`);
      return driver.execute(cmd);
    });

经过测试：

Chrome 67.0.3396.99
Chromedriver 2.36.540469
selenium-cucumber-js 1.5.12
selenium-webdriver 3.0.0

Answer 8

以下等效于Java，Selenium，chromedriver和chrome v71.x。输入的代码是允许保存下载内容的关键其他jar：com.fasterxml.jackson.core，com.fasterxml.jackson.annotation，com.fasterxml.jackson.databind

System.setProperty（“ webdriver.chrome.driver”，“ C：\ libraries \ chromedriver.exe”）;

            String downloadFilepath = "C:\\Download";
            HashMap<String, Object> chromePreferences = new HashMap<String, Object>();
            chromePreferences.put("profile.default_content_settings.popups", 0);
            chromePreferences.put("download.prompt_for_download", "false");
            chromePreferences.put("download.default_directory", downloadFilepath);
            ChromeOptions chromeOptions = new ChromeOptions();
            chromeOptions.setBinary("C:\\pathto\\Chrome SxS\\Application\\chrome.exe");

            //ChromeOptions options = new ChromeOptions();
            //chromeOptions.setExperimentalOption("prefs", chromePreferences);
            chromeOptions.addArguments("start-maximized");
            chromeOptions.addArguments("disable-infobars");


            //HEADLESS CHROME
            **chromeOptions.addArguments("headless");**

            chromeOptions.setExperimentalOption("prefs", chromePreferences);
            DesiredCapabilities cap = DesiredCapabilities.chrome();
            cap.setCapability(CapabilityType.ACCEPT_SSL_CERTS, true);
            cap.setCapability(ChromeOptions.CAPABILITY, chromeOptions);

            **ChromeDriverService driverService = ChromeDriverService.createDefaultService();
            ChromeDriver driver = new ChromeDriver(driverService, chromeOptions);

            Map<String, Object> commandParams = new HashMap<>();
            commandParams.put("cmd", "Page.setDownloadBehavior");
            Map<String, String> params = new HashMap<>();
            params.put("behavior", "allow");
            params.put("downloadPath", downloadFilepath);
            commandParams.put("params", params);
            ObjectMapper objectMapper = new ObjectMapper();
            HttpClient httpClient = HttpClientBuilder.create().build();
            String command = objectMapper.writeValueAsString(commandParams);
            String u = driverService.getUrl().toString() + "/session/" + driver.getSessionId() + "/chromium/send_command";
            HttpPost request = new HttpPost(u);
            request.addHeader("content-type", "application/json");
            request.setEntity(new StringEntity(command));**
            try {
                httpClient.execute(request);
            } catch (IOException e2) {
                // TODO Auto-generated catch block
                e2.printStackTrace();
            }**

        //Continue using the driver for automation  
    driver.manage().window().maximize();

Answer 9

我通过使用@Shawn Button共享的解决方法并为参数使用完整路径解决了这个问题。使用相对路径不起作用，并给我错误。

版本：
Chrome版本75.0.3770.100（正式版本）（32位）
ChromeDriver 75.0.3770.90

Answer 10

使用：google-chrome-stable amd64 86.0.4240.111-1，chromedriver 86.0.4240.22，selenium 3.141.0 python 3.8.3

尝试了多种提议的解决方案，但对于无头的chrome并没有真正起作用，我的测试网站也打开了一个新的空白标签，然后下载了数据。

最后放弃了无头程序，并实现了pyvirtualdisplay和xvfd以模拟X服务器，例如：

from selenium.webdriver.chrome.options import Options # and other imports
import selenium.webdriver as webdriver
import tempfile

url = "https://really_badly_programmed_website.org"

tmp_dir = tempfile.mkdtemp(prefix="hamster_")

driver_path="/usr/bin/chromedriver"

chrome_options = Options() 
chrome_options.binary_location = "/usr/bin/google-chrome"

prefs = {'download.default_directory': tmp_dir,}
chrome_options.add_experimental_option("prefs", prefs)

with Display(backend="xvfb",size=(1920,1080),color_depth=24) as disp:

    driver = webdriver.Chrome(options=chrome_options, executable_path=driver_path)
    driver.get(url)

最后一切正常，并将dowload文件保存在tmp文件夹中。

Answer 11

我终于通过升级到 Chromium 90 让它工作了！我之前有 72-78 版本，但我看到它最近已修复：https://bugs.chromium.org/p/chromium/issues/detail?id=696481 所以我决定试一试。

所以升级后，花了一段时间（MacOS 中的自制软件太慢了......），我只是做了，没有设置选项或任何东西（这是一个 JavaScript 示例）：

await driver.findElement(By.className('download')).click();

它奏效了！我在我一直试图下载的同一个工作文件夹中看到了下载的 PDF...

下载铬无头和硒

11 个答案: