Chrome specific functionality

These are capabilities and features specific to Google Chrome browsers.

By default, Selenium 4 is compatible with Chrome v75 and greater. Note that the version of the Chrome browser and the version of chromedriver must match the major version.

Options

Capabilities common to all browsers are described on the Options page.

Capabilities unique to Chrome and Chromium are documented at Google’s page for Capabilities & ChromeOptions

Starting a Chrome session with basic defined options looks like this:

    ChromeOptions options = new ChromeOptions();
    driver = new ChromeDriver(options);
    options = webdriver.ChromeOptions()
    driver = webdriver.Chrome(options=options)
            var options = new ChromeOptions();
            driver = new ChromeDriver(options);
      options = Selenium::WebDriver::Options.chrome
      @driver = Selenium::WebDriver.for :chrome, options: options
    const Options = new Chrome.Options();
    let driver = new Builder()
      .forBrowser(Browser.CHROME)
      .setChromeOptions(Options)
      .build();

Arguments

The args parameter is for a list of command line switches to be used when starting the browser. There are two excellent resources for investigating these arguments:

Commonly used args include --start-maximized, --headless=new and --user-data-dir=...

Add an argument to options:

    options.addArguments("--start-maximized");
    options.add_argument("--start-maximized")
            options.AddArgument("--start-maximized");
      options.args << '--start-maximized'
    let driver = new Builder()
      .forBrowser(Browser.CHROME)
      .setChromeOptions(options.addArguments('--headless=new'))
      .build();

Start browser in a specified location

The binary parameter takes the path of an alternate location of browser to use. With this parameter you can use chromedriver to drive various Chromium based browsers.

Add a browser location to options:

    options.setBinary(getChromeLocation());
    options.binary_location = chrome_bin
            options.BinaryLocation = GetChromeLocation();
      options.binary = chrome_location
    let driver = new Builder()
      .forBrowser(Browser.CHROME)
      .setChromeOptions(options.setChromeBinaryPath(`Path to chrome binary`))
      .build();

Add extensions

The extensions parameter accepts crx files. As for unpacked directories, please use the load-extension argument instead, as mentioned in this post.

Add an extension to options:

    options.addExtensions(extensionFilePath);
    options.add_extension(extension_file_path)
            options.AddExtension(extensionFilePath);
      options.add_extension(extension_file_path)
    const options = new Chrome.Options();
    let driver = new Builder()
      .forBrowser(Browser.CHROME)
      .setChromeOptions(options.addExtensions(['./test/resources/extensions/webextensions-selenium-example.crx']))
      .build();

Keeping browser open

Setting the detach parameter to true will keep the browser open after the process has ended, so long as the quit command is not sent to the driver.

Note: This is already the default behavior in Java.

    options.add_experimental_option("detach", True)

Note: This is already the default behavior in .NET.

      options.detach = true
    let driver = new Builder()
      .forBrowser(Browser.CHROME)
      .setChromeOptions(options.detachDriver(true))
      .build();

Excluding arguments

Chromedriver has several default arguments it uses to start the browser. If you do not want those arguments added, pass them into excludeSwitches. A common example is to turn the popup blocker back on. A full list of default arguments can be parsed from the Chromium Source Code

Set excluded arguments on options:

    options.setExperimentalOption("excludeSwitches", List.of("disable-popup-blocking"));
    options.add_experimental_option('excludeSwitches', ['disable-popup-blocking'])
            options.AddExcludedArgument("disable-popup-blocking");
      options.exclude_switches << 'disable-popup-blocking'
    let driver = new Builder()
      .forBrowser(Browser.CHROME)
      .setChromeOptions(options.excludeSwitches('enable-automation'))
      .build();

Service

Examples for creating a default Service object, and for setting driver location and port can be found on the Driver Service page.

Log output

Getting driver logs can be helpful for debugging issues. The Service class lets you direct where the logs will go. Logging output is ignored unless the user directs it somewhere.

File output

To change the logging output to save to a specific file:

    ChromeDriverService service =
        new ChromeDriverService.Builder().withLogFile(logLocation).build();

Note: Java also allows setting file output by System Property:
Property key: ChromeDriverService.CHROME_DRIVER_LOG_PROPERTY
Property value: String representing path to log file

Selenium v4.11

    service = webdriver.ChromeService(log_output=log_path)
            service.LogPath = GetLogLocation();

Console output

To change the logging output to display in the console as STDOUT:

Selenium v4.10

    ChromeDriverService service =
        new ChromeDriverService.Builder().withLogOutput(System.out).build();

Note: Java also allows setting console output by System Property;
Property key: ChromeDriverService.CHROME_DRIVER_LOG_PROPERTY
Property value: DriverService.LOG_STDOUT or DriverService.LOG_STDERR

Selenium v4.11

    service = webdriver.ChromeService(log_output=subprocess.STDOUT)

$stdout and $stderr are both valid values

Selenium v4.10

      service.log = $stdout

Log level

There are 6 available log levels: ALL, DEBUG, INFO, WARNING, SEVERE, and OFF. Note that --verbose is equivalent to --log-level=ALL and --silent is equivalent to --log-level=OFF, so this example is just setting the log level generically:

Selenium v4.8

    ChromeDriverService service =
        new ChromeDriverService.Builder().withLogLevel(ChromiumDriverLogLevel.DEBUG).build();

Note: Java also allows setting log level by System Property:
Property key: ChromeDriverService.CHROME_DRIVER_LOG_LEVEL_PROPERTY
Property value: String representation of ChromiumDriverLogLevel enum

Selenium v4.11

    service = webdriver.ChromeService(service_args=['--log-level=DEBUG'], log_output=subprocess.STDOUT)

Selenium v4.10

      service.args << '--log-level=DEBUG'

Log file features

There are 2 features that are only available when logging to a file:

  • append log
  • readable timestamps

To use them, you need to also explicitly specify the log path and log level. The log output will be managed by the driver, not the process, so minor differences may be seen.

Selenium v4.8

    ChromeDriverService service =
        new ChromeDriverService.Builder().withAppendLog(true).withReadableTimestamp(true).build();

Note: Java also allows toggling these features by System Property:
Property keys: ChromeDriverService.CHROME_DRIVER_APPEND_LOG_PROPERTY and ChromeDriverService.CHROME_DRIVER_READABLE_TIMESTAMP
Property value: "true" or "false"

    service = webdriver.ChromeService(service_args=['--append-log', '--readable-timestamp'], log_output=log_path)

Selenium v4.8

      service.args << '--append-log'
      service.args << '--readable-timestamp'

Disabling build check

Chromedriver and Chrome browser versions should match, and if they don’t the driver will error. If you disable the build check, you can force the driver to be used with any version of Chrome. Note that this is an unsupported feature, and bugs will not be investigated.

Selenium v4.8

    ChromeDriverService service =
        new ChromeDriverService.Builder().withBuildCheckDisabled(true).build();

Note: Java also allows disabling build checks by System Property:
Property key: ChromeDriverService.CHROME_DRIVER_DISABLE_BUILD_CHECK
Property value: "true" or "false"

Selenium v4.11

    service = webdriver.ChromeService(service_args=['--disable-build-check'], log_output=subprocess.STDOUT)
            service.DisableBuildCheck = true;

Selenium v4.8

      service.args << '--disable-build-check'

Special Features

Some browsers have implemented additional features that are unique to them.

Casting

You can drive Chrome Cast devices, including sharing tabs

      sinks = @driver.cast_sinks
      unless sinks.empty?
        device_name = sinks.first['name']
        @driver.start_cast_tab_mirroring(device_name)
        expect { @driver.stop_casting(device_name) }.not_to raise_exception
      end

Network conditions

You can simulate various network conditions.

    network_conditions = {
        "offline": False,
        "latency": 20,  # 20 ms of latency
        "download_throughput": 2000 * 1024 / 8,  # 2000 kbps
        "upload_throughput": 2000 * 1024 / 8,    # 2000 kbps
    }
    driver.set_network_conditions(**network_conditions)
      @driver.network_conditions = {offline: false, latency: 100, throughput: 200}

Logs

Permissions

    driver.setPermission("camera", "denied");
    driver.set_permissions('camera', 'denied')
      @driver.add_permission('camera', 'denied')
      @driver.add_permissions('clipboard-read' => 'denied', 'clipboard-write' => 'prompt')

DevTools

See the Chrome DevTools section for more information about using Chrome DevTools