selenium_notes.md

Using Selenium

Installation

Install the WebDrivers.

Firefox on Ubuntu Linux:

sudo apt install firefox-geckodriver

Chrome on Ubuntu Linux:

sudo apt install chromium-chromedriver

Create a new node project and install the selenium-webdriver:

npm install --save selenium-webdriver

Docker

TODO.

Example setup

Firefox

A skeleton selenium-webdriver setup using Firefox:

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

(async function skeleton() {
  let driver = await new Builder().forBrowser('firefox').build();
  try {
    await driver.get('https://example.com/');
    await driver.wait(until.titleIs('Example Title'), 2000);
  } finally {
    await driver.quit();
  }
})();

Chrome

Default:

const browser = await new Builder().forBrowser('chrome');
const driver = await browser.build();

With options (notice the goog:chromeOptions key):

// Chrome with options -
const chromeOpts = {
  args: [
    '--start-maximized',
    '--use-fake-ui-for-media-stream'
  ],
};
let chromeCaps = Capabilities.chrome();
// Specify both options for grid or local use, see:
// https://github.com/webdriverio/webdriverio/issues/2645#issuecomment-407034467
chromeCaps = {
  ...chromeCaps,
  'browserName': 'chrome',
  'chromeOptions': chromeOpts,
  'goog:chromeOptions': chromeOpts,
};
const driver = await new Builder().withCapabilities(chromeCaps).build();

Cookbook

Note that most calls return promises.

Find an element by name attribute

const el = await driver.findElement(By.name('some-elem'));

Send text input to an element

const el = await driver.findElement(By.name('some-elem'));
await el.sendKeys('some text', Key.RETURN);

Find an element that contains specific text

const el = await driver.findElement(By.xpath("//*[contains(text(), 'some text')]"));

Click an element

...
el.click();

Find an element by placeholder text

const el = await driver.findElement(By.xpath("//input[@placeholder='some placeholder']"));

Get the value of an attribute for an element

const val = await el.getAttribute('some_attr');

Find the parent of an element

const el = await driver.findElement(By.xpath("//*[contains(text(), 'something')]"));
const parentEl = await el.findElement(By.xpath("./.."));

Get the page title

const title = await driver.getTitle();

Wait until the page title is some value

Wait with a timeout of 2 seconds:

await driver.wait(until.titleIs('Some Title'), 2000);

Wait until an element is located

await driver.wait(until.elementLocated(By.xpath("//*[@placeholder='some value']")));

Wait for a custom predicate

await driver.wait(async () => {
  const val = await el.getAttribute('value');
  return val.match(/^some pattern/);
}, 2000);

Switch windows

Enumerate windows and switch to the last one (assumes a single starting window with a second window just opened):

const wins = await driver.getAllWindowHandles();
await driver.switchTo().window(wins[wins.length - 1]);

Interact with or dismiss a Javascript alert

const jsAlert = await driver.switchTo().alert();
jsAlert.accept();