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I'm using python-selenium and Chrome 59 and trying to automate a simple download sequence. When I launch the browser normally, the download works, but when I do so in headless mode, the download doesn't work.
# 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
I've even tried adding a default path:
prefs = {"download.default_directory" : "/Users/Chetan/Desktop/"}
chromeOptions.add_argument("headless")
chromeOptions.add_experimental_option("prefs",prefs)
Adding a default path works in the normal implementation, but the same problem persists in the headless version.
How do I get the download to start in headless mode?
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Yes, it's a "feature", for security. As mentioned before here is the bug discussion: https://bugs.chromium.org/p/chromium/issues/detail?id=696481
Support was added in chrome version 62.0.3196.0 or above to enable downloading.
Here is a python implementation. I had to add the command to the chromedriver commands. I will try to submit a PR so it is included in the library in the future.
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/$sessionId/chromium/send_command')
params = {'cmd': 'Page.setDownloadBehavior', 'params': {'behavior': 'allow', 'downloadPath': download_dir}}
command_result = driver.execute("send_command", params)
For reference here is a little repo to demonstrate how to use this:
https://github.com/shawnbutton/PythonHeadlessChrome
update 2020-05-01 There have been comments saying this is not working anymore. Given this patch is now over a year old it's quite possible they have changed the underlying library.
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The Chromium developers recently added a 2nd headless mode (in 2021). See https://bugs.chromium.org/p/chromium/issues/detail?id=706008#c36
They later renamed the option in 2023 for Chrome 109 -> https://github.com/chromium/chromium/commit/e9c516118e2e1923757ecb13e6d9fff36775d1f4
For Chrome 109 and above, the --headless=new flag will now allow you to get the full functionality of Chrome in the new headless mode, and you can even run extensions in it. (For Chrome versions 96 through 108, use --headless=chrome)
Usage: (Chrome 109 and above):
options.add_argument("--headless=new")
Usage: (Chrome 96 through Chrome 108):
options.add_argument("--headless=chrome")
If something works in regular Chrome, it should now work with the newer headless mode too.
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Here's a working example for Python based on Shawn Button's answer. I've tested this with Chromium 68.0.3440.75 & chromedriver 2.38
from selenium import webdriver
from selenium.webdriver.chrome.options import Options
chrome_options = Options()
chrome_options.add_experimental_option("prefs", {
"download.default_directory": "/path/to/download/dir",
"download.prompt_for_download": False,
chrome_options.add_argument("--headless")
driver = webdriver.Chrome(chrome_options=chrome_options)
driver.command_executor._commands["send_command"] = ("POST", '/session/$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()
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This is a feature of Chrome to prevent from software to download files to your computer. There is a workaround though. Read more about it here.
What you need to do is enable it via DevTools, Something like that:
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();
This is the solution some one gave in the mentioned topic. Here is his comment.
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UPDATED PYTHON SOLUTION -
TESTED Mar 4, 2021 on chromedriver v88 and v89
This will allow you to click to download files in headless mode.
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()
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Maybe the website that you handle returns different HTML pages for browsers, means the XPath or Id that you want maybe differently in headless browser.
Try to download pageSource in headless browser and open it as HTML page to see the Id or XPath that you want.
You can see this as c# example How to hide FirefoxDriver (using Selenium) without findElement function error in PhantomDriver? .
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A full working example for JavaScript with selenium-cucumber-js / selenium-webdriver:
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/${session.getId()}/chromium/send_command`);
return driver.execute(cmd);
return driver;
The key part is:
driver.getSession()
.then(session => {
const cmd = new command.Command("SEND_COMMAND")
.setParameter("cmd", "Page.setDownloadBehavior")
.setParameter("params", {'behavior': 'allow', 'downloadPath': '/tmp/downloads'});
driver.getExecutor().defineCommand("SEND_COMMAND", "POST", `/session/${session.getId()}/chromium/send_command`);
return driver.execute(cmd);
Tested with:
Chrome 67.0.3396.99
Chromedriver 2.36.540469
selenium-cucumber-js 1.5.12
selenium-webdriver 3.0.0
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Usually it's redundant seeing the same thing just written in another language, but because this issue drove me crazy, I hope I'm saving someone else from the pain... so here's the C# version of Shawn Button's answer (tested with headless chrome=71.0.3578.98, chromedriver=2.45.615279, platform=Linux 4.9.125-linuxkit x86_64)):
var enableDownloadCommandParameters = new Dictionary<string, object>
{ "behavior", "allow" },
{ "downloadPath", downloadDirectoryPath }
var result = ((OpenQA.Selenium.Chrome.ChromeDriver)driver).ExecuteChromeCommandWithResult("Page.setDownloadBehavior", enableDownloadCommandParameters);
Following is the equivalent in Java, selenium, chromedriver and chrome v 71.x. The code in is the key to allow saving of downloads
Additional jars: 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();
I solved this problem by using the workaround shared by @Shawn Button and using the full path for the 'downloadPath' parameter. Using a relative path did not work and give me the error.
Versions:
Chrome Version 75.0.3770.100 (Official Build) (32-bit)
ChromeDriver 75.0.3770.90
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Using: google-chrome-stable amd64 86.0.4240.111-1,chromedriver 86.0.4240.22, selenium 3.141.0 python 3.8.3
Tried multiple proposed solutions, and nothing really worked for chrome headless, also my testing website opens a new blank tab and then the data is downloaded.
Finally gave up on headless and implemented pyvirtualdisplay and xvfd to emulate X server, something like:
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)
At the end everything worked and had the dowload file on the tmp folder.
I finally got it to work by upgrading to Chromium 90! I previously had version 72-78, but I saw that it had been fixed recently: https://bugs.chromium.org/p/chromium/issues/detail?id=696481 so i decided to give it a shot.
So after upgrading, which took a while (home brew in MacOS is so slow...), I simply did, without setting options or anything (this is a JavaScript example):
await driver.findElement(By.className('download')).click();
And it worked! I saw the downloaded PDF in the same working folder that I had been trying to download for a long time...
After updating chromium from 108 to 110: WebDriverException: Message: unknown error: unable to discover open pages
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