@axe-core/cli

@axe-core/cli

Provides a command line interface for axe to run quick accessibility tests.

Previous versions of this program were maintained at dequelabs/axe-cli.

Getting Started

Install Node.js if you haven't already. This project requires Node 6+. By default, axe-cli runs Chrome in headless mode, which requires Chrome 59 or up.

Install axe CLI globally: npm install @axe-core/cli -g

Lastly, install the webdrivers of the browsers you wish to use. A webdriver is a driver for your web browsers. It allows other programs on your machine to open a browser and operate it.

To install the latest version of Chromedriver globally, install browser-driver-manager: npm install -g browser-driver-manager. Then run npx browser-driver-manager install chrome.

Current information about other available webdrivers can be found at selenium-webdriver project. Alternatively, you could use Webdriver manager

Usage

After installing, you can now run the axe command in your CLI, followed by the URL of the page you wish to test:

axe https://www.deque.com

You can run multiple pages at once, simply add more URLs to the command. Keep in mind that axe-cli is not a crawler, so if you find yourself testing dozens of pages at once, you may want to consider switching over to something like @axe-core/webdriverjs. If you do not specify the protocol, http will be used by default:

axe www.deque.com, dequeuniversity.com

Running specific rules

You can use the --rules flag to set which rules you wish to run, or you can use --tags to tell axe to run all rules that have that specific tag. For example:

axe www.deque.com --rules color-contrast,html-has-lang

Or, to run all wcag2a rules:

axe www.deque.com --tags wcag2a

In case you want to disable some rules, you can use --disable followed by a list of rules. These will be skipped when analyzing the site:

axe www.deque.com --disable color-contrast

This option can be combined with either --tags or --rules.

A list of rules and what tags they have is available at: https://dequeuniversity.com/rules/worldspace/3.0/.

Saving the results

Results can be saved as JSON data, using the --save and --dir flags. By passing a filename to --save you indicate how the file should be called. If no filename is passed, a default will be used. For example:

axe www.deque.com --save deque-site.json

Or:

axe www.deque.com --dir ./axe-results/

Sending results to STDOUT

To output the test results to STDOUT, provide the --stdout flag. This flag has the side-effect of silencing all other logs/output (other than errors, which are written to STDERR).

To print the entire result object to your terminal, do:

axe --stdout www.deque.com

To pipe the results to a file, do:

axe --stdout www.deque.com > your_file.json

To pipe the results to a JSON-parsing program for further processing, do:

axe --stdout www.deque.com | jq ".[0].violations"

Defining the scope of a test

If you want to only test a specific area of a page, or wish to exclude some part of a page you can do so using the --include and --exclude flags and pass it a CSS selector:

axe www.deque.com --include "#main" --exclude "#aside"

You may pass multiple selectors with a comma-delimited string. For example:

axe www.deque.com --include "#div1,#div2,#div3"

Custom axe-core versions

Axe-cli will look for locally available versions of axe-core. If the directory from where you start axe-cli has an axe.js file, or has a node_modules directory with axe-core installed in it. Axe-cli will use this version of axe-core instead of the default version installed globally.

To specify the exact file axe-core file axe-cli should use, you can use the --axe-source flag (-a for short), with a relative or absolute path to the file.

axe www.deque.com --axe-source ./axe.nl.js

Different browsers

Axe-cli can run in a variety of web browsers. By default axe-cli uses Chrome in headless mode. But axe-cli is equally capable of testing pages using other web browsers. Running in another browser requires that browser's webdriver to be available on your PATH. You can find a list of available webdrivers and how to install them at: https://www.selenium.dev/documentation/en/webdriver/

To run axe-cli using another browser, pass it in as the --browser option:

axe www.deque.com --browser chrome

Or for short:

axe www.deque.com -b c

Custom Chrome Flags

When using the Headless Chrome browser, you may provide any number of flags to configure how the browser functions.

Options are passed by name, without their leading -- prefix. For example, to provide the --no-sandbox --disable-setuid-sandbox --disable-dev-shm-usage flags to the Chrome binary, you'd do:

axe --chrome-options="no-sandbox,disable-setuid-sandbox,disable-dev-shm-usage" www.deque.com

CI integration

Axe-cli can be ran within the CI tooling for your project. Many tools are automatically configured to halt/fail builds when a process exits with a code of 1.

Use the --exit flag, -q for short, to have the axe-cli process exit with a failure code 1 when any rule fails to pass.

axe www.deque.com --exit

Timing and timeout

For debugging and managing timeouts, there are two options available. With --timer set, axe-cli will log how long it takes to load the page, and how long it takes to run axe-core. If you find the execution of axe-core takes too long, which can happen on very large pages, use --timeout to increase the time axe has to test that page:

axe www.cnn.com --timeout=120

Delay audit to ensure page is loaded

If you find your page is not ready after axe has determined it has loaded, you can use --load-delay followed by a number in milliseconds. This will make axe wait that time before running the audit after the page has loaded.

axe www.deque.com --load-delay=2000

Verbose output

To see additional information like test tool name, version and environment details, use the --verbose flag, -v for short.

axe www.deque.com --verbose

ChromeDriver Path

If you need to test your page using an older version of Chrome, you can use --chromedriver-path followed by the absolute path to the desired version of the ChromeDriver executable.

axe www.deque.com --chromedriver-path="absolute/path/to/chromedriver"