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Capabilities & ChromeOptions
Capabilities & ChromeOptions
Capabilities are options that you can use to customize and configure a ChromeDriver session. This page documents all ChromeDriver supported capabilities and how to use them.
There are two ways to specify capabilities.
- The first is to use the
ChromeOptionsclass. - If your client library does not have a
ChromeOptionsclass (like the selenium ruby client), you can specify the capabilities directly as part of theDesiredCapabilities.
Using the ChromeOptions class
You can create an instance ofChromeOptions, which has convenient methods for setting ChromeDriver-specific capabilities. You can pass the ChromeOptions object directly into the ChromeDriver constructor: ChromeOptions options = new ChromeOptions();
options.addExtensions(new File("/path/to/extension.crx"));
ChromeDriver driver = new ChromeDriver(options);
Alternatively, you can add the options to an already existing DesiredCapabilities object, which is useful when need to specify other WebDriver capabilities not specific to ChromeDriver.
DesiredCapabilities capabilities = DesiredCapabilities.chrome();
// Add the WebDriver proxy capability.
Proxy proxy = new Proxy();
proxy.setHttpProxy("myhttpproxy:3337");
capabilities.setCapability("proxy", proxy);
// Add ChromeDriver-specific capabilities through ChromeOptions.
ChromeOptions options = new ChromeOptions();
options.addExtensions(new File("/path/to/extension.crx"));
capabilities.setCapability(ChromeOptions.CAPABILITY, options);
ChromeDriver driver = new ChromeDriver(capabilities);
Using DesiredCapabilities directly
The ChromeOptions class uses DesiredCapabilities underneath. To use DesiredCapabilities directly, you need to know the name of the capability and the type of value it takes. See the full list further below.
Java
Map<String, Object> chromeOptions = new Map<String, Object>();
chromeOptions.put("binary", "/usr/lib/chromium-browser/chromium-browser");
DesiredCapabilities capabilities = DesiredCapabilities.chrome();
capabilities.setCapability(ChromeOptions.CAPABILITY, chromeOptions);
WebDriver driver = new ChromeDriver(capabilities);
Ruby
caps = Selenium::WebDriver::Remote::Capabilities.chrome("chromeOptions" => {"args" => [ "--disable-web-security" ]})
driver = Selenium::WebDriver.for :remote, url: 'http://localhost:4444/wd/hub' desired_capabilities: caps
Common use cases
Use custom profile (also called user data directory)
By default, ChromeDriver will create a new temporary profile for each session. At times you may want to set special preferences or just use a custom profile altogether. If the former, you can use the 'chrome.prefs' capability (described later below) to specify preferences that will be applied after Chrome starts. If the latter, you can use theuser-data-dir Chrome command-line switch to tell Chrome which profile to use:
ChromeOptions options = new ChromeOptions();
options.addArguments("user-data-dir=/path/to/your/custom/profile");
You can create your own custom profile by just running Chrome (on the command-line or through ChromeDriver) with the user-data-dir switch set to some new directory. If the path doesn't exist, Chrome will create a new profile in the specified location. You can then modify the profile settings as desired, and ChromeDriver can use the profile in the future. Open chrome://version in the browser to see what profile Chrome is using.
Start Chrome maximized
ChromeOptions options = new ChromeOptions();
options.addArguments("start-maximized");
Using a Chrome executable in a non-standard location
ChromeOptions options = new ChromeOptions();
options.setBinary("/path/to/other/chrome/binary");
Set a Chrome preference
ChromeOptions options = new ChromeOptions();
Map<String, Object> prefs = new HashMap<String, Object>();
prefs.put("profile.default_content_settings.popups", 0);
options.setExperimentalOption("prefs", prefs);
List of recognized capabilities
This is a list of all the WebDriver-standard capabilities that ChromeDriver supports:
Proxy object
See http://code.google.com/p/selenium/wiki/DesiredCapabilities#Proxy_JSON_Object
loggingPrefs object
See https://code.google.com/p/selenium/wiki/DesiredCapabilities#JSON_object
chromeOptions object
This is a list of all the Chrome-specific desired capabilities, which all are under the chromeOptions dictionary. If possible, use the ChromeOptions class instead of specifying these directly.
Name
Type
Default
Description
args
list of strings
List of command-line arguments to use when starting Chrome. Arguments with an associated value should be separated by a '=' sign (e.g., ['start-maximized', 'user-data-dir=/tmp/temp_profile']). See here for a list of Chrome arguments.
binary
string
Path to the Chrome executable to use (on Mac OS X, this should be the actual binary, not just the app. e.g., '/Applications/Google Chrome.app/Contents/MacOS/Google Chrome')
extensions
list of strings
A list of Chrome extensions to install on startup. Each item in the list should be a base-64 encoded packed Chrome extension (.crx)
localState
dictionary
A dictionary with each entry consisting of the name of the preference and its value. These preferences are applied to the Local State file in the user data folder.
prefs
dictionary
A dictionary with each entry consisting of the name of the preference and its value. These preferences are only applied to the user profile in use. See the 'Preferences' file in Chrome's user data directory for examples.
detach
boolean
false
If false, Chrome will be quit when ChromeDriver is killed, regardless of whether the session is quit. If true, Chrome will only be quit if the session is quit (or closed). Note, if true, and the session is not quit, ChromeDriver cannot clean up the temporary user data directory that the running Chrome instance is using.
debuggerAddress
string
An address of a Chrome debugger server to connect to, in the form of <hostname/ip:port>, e.g. '127.0.0.1:38947'
excludeSwitches
list of strings
List of Chrome command line switches to exclude that ChromeDriver by default passes when starting Chrome. Do not prefix switches with --.
minidumpPath
string
Directory to store Chrome minidumps . (Supported only on Linux.)
mobileEmulation
dictionary
A dictionary with either a value for “deviceName,” or values for “deviceMetrics” and “userAgent.” Refer to Mobile Emulation for more information.
perfLoggingPrefs
dictionary
An optional dictionary that specifies performance logging preferences. See below for more information.
windowTypes
list of strings
A list of window types that will appear in the list of window handles. For access to <webview> elements, include "webview" in this list.
perfLoggingPrefs object
The perfLoggingPrefs dictionary has the following format (all keys are optional):
Name
Type
Default
Description
enableNetwork
boolean
true
Whether or not to collect events from Network domain.
enablePage
boolean
true
Whether or not to collect events from Page domain.
enableTimeline
boolean
true (false if tracing is enabled)
Whether or not to collect events from Timeline domain. Note: when tracing is enabled, Timeline domain is implicitly disabled, unless enableTimeline is explicitly set to true.
tracingCategories
string
(empty)
A comma-separated string of Chrome tracing categories for which trace events should be collected. An unspecified or empty string disables tracing.
bufferUsageReportingInterval
positive integer
1000
The requested number of milliseconds between DevTools trace buffer usage events. For example, if 1000, then once per second, DevTools will report how full the trace buffer is. If a report indicates the buffer usage is 100%, a warning will be issued.
Returned Capabilities
This is a list of all the Chrome-specific returned capabilities. (i.e., what ChromeDriver returns when you create a new session)
Name
Type
Description
chrome.chromedriverVersion
string
version of ChromeDriver
userDataDir
string
path to user data directory that Chrome is using; note, this is inside a 'chrome' dictionary
ChromeDriver server command line arguments
Run chromedriver --help to see command line arguments for your version.