/Selenium

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Selenium

selenium-webdriver

Selenium is a browser automation library. Most often used for testing web-applications, Selenium may be used for any task that requires automating interaction with the browser.

Installation

Selenium may be installed via npm with

npm install selenium-webdriver

You will need to download additional components to work with each of the major browsers. The drivers for Chrome, Firefox, and Microsoft's IE and Edge web browsers are all standalone executables that should be placed on your system [PATH]. Apple's safaridriver is shipped with Safari 10 for OS X El Capitan and macOS Sierra. You will need to enable Remote Automation in the Develop menu of Safari 10 before testing.

Browser Component
Chrome [chromedriver(.exe)][chrome]
Internet Explorer [IEDriverServer.exe][release]
Edge [MicrosoftWebDriver.msi][edge]
Firefox [geckodriver(.exe)][geckodriver]
Safari [safaridriver]

Usage

The sample below and others are included in the example directory. You may also find the tests for selenium-webdriver informative.

const {Builder, By, Key, until} = require('selenium-webdriver');

(async function example() {
  let driver = await new Builder().forBrowser('firefox').build();
  try {
    await driver.get('http://www.google.com/ncr');
    await driver.findElement(By.name('q')).sendKeys('webdriver', Key.RETURN);
    await driver.wait(until.titleIs('webdriver - Google Search'), 1000);
  } finally {
    await driver.quit();
  }
})();

Using the Builder API

The Builder class is your one-stop shop for configuring new WebDriver instances. Rather than clutter your code with branches for the various browsers, the builder lets you set all options in one flow. When you call Builder#build(), all options irrelevant to the selected browser are dropped:

const webdriver = require('selenium-webdriver');
const chrome = require('selenium-webdriver/chrome');
const firefox = require('selenium-webdriver/firefox');

let driver = new webdriver.Builder()
    .forBrowser('firefox')
    .setChromeOptions(/* ... */)
    .setFirefoxOptions(/* ... */)
    .build();

Why would you want to configure options irrelevant to the target browser? The Builder's API defines your default configuration. You can change the target browser at runtime through the SELENIUM_BROWSER environment variable. For example, the example/google_search.js script is configured to run against Firefox. You can run the example against other browsers just by changing the runtime environment

# cd node_modules/selenium-webdriver
node example/google_search
SELENIUM_BROWSER=chrome node example/google_search
SELENIUM_BROWSER=safari node example/google_search

The Standalone Selenium Server

The standalone Selenium Server acts as a proxy between your script and the browser-specific drivers. The server may be used when running locally, but it's not recommend as it introduces an extra hop for each request and will slow things down. The server is required, however, to use a browser on a remote host (most browser drivers, like the IEDriverServer, do not accept remote connections).

To use the Selenium Server, you will need to install the JDK and download the latest server from [Selenium][release]. Once downloaded, run the server with

java -jar selenium-server-standalone-2.45.0.jar

You may configure your tests to run against a remote server through the Builder API:

let driver = new webdriver.Builder()
    .forBrowser('firefox')
    .usingServer('http://localhost:4444/wd/hub')
    .build();

Or change the Builder's configuration at runtime with the SELENIUM_REMOTE_URL environment variable:

SELENIUM_REMOTE_URL="http://localhost:4444/wd/hub" node script.js

You can experiment with these options using the example/google_search.js script provided with selenium-webdriver.

Documentation

API documentation is available online from the [Selenium project][api]. Additional resources include