Selenium
Tips & Tricks
by Dave Haeffner

New to Selenium?
• Selenium Bootcamp http://se.tips/se-bootcamp
• Selenium Guidebook http://se.tips/se-guidebook
• Weekly Selenium Tips http://se.tips/se-weekly-tips

http://ElementalSelenium.com

http://the-internet.herokuapp.com/

Headless
Benefits:
- Speed
- Maintenance
- Screenshotting
http://se.tips/all-headless-browsers

Headless w/ Xvfb
http://elementalselenium.com/tips/38-headless

Why use it?
Ideal for running small test suites on a headless machine
e.g., a Continuous Integration (CI) Server

NOTE
- display port collisions
- use unique values
- e.g., CI build number

NOTE
- display port collisions
- use unique values
- e.g., CI build number

Headless w/ GhostDriver
http://elementalselenium.com/tips/46-headless-ghostdriver

http://phantomjs.org/

Why use it?
• Faster execution times
• Also useful for a CI server
• Not limited to just Linux

Step 2 - Start PhantomJS w/ WebDriver flag
Step 1 - Download PhantomJS
http://phantomjs.org/download.html
Step 3 - Connect Your Test to PhantomJS
using Selenium Remote
NOTE
You can also connect PhantomJS to a Selenium Grid
http://se.tips/ghost-driver-grid
Option 1

Step 2 - Tell Selenium where it is
Step 1 - Download PhantomJS
http://phantomjs.org/download.html
Step 3 - Launch Selenium with PhantomJS locally
Option 2

Visual Testing

A Visual Testing Primer
• Check that an application’s UI appears correctly
• Can also be used to verify content
• Hundreds of assertions for a few lines of code

Visual Testing Challenges
• Managing complexity
• False positives
• e.g., shifting content, dynamic content, typos

In pom.xml

Visual Testing Write-ups
http://se.tips/se-visual-1 Getting Started
http://se.tips/se-visual-2 False Positives part 1
http://se.tips/se-visual-3 False Positives part 2
http://se.tips/se-visual-4 Add Visual Testing To Your Existing Tests
http://se.tips/se-visual-5 Add Visual Testing To Your BDD Tests

Selenium Grid Resources
• http://elementalselenium.com/tips/26-cloud
• http://elementalselenium.com/tips/52-grid
• http://elementalselenium.com/tips/70-grid-extras

Fun with a Proxy Server

Selenium Browser
Proxy
Server
Application
Under
Test

http://bmp.lightbody.net/

HTTP Status Codes
http://elementalselenium.com/tips/17-retrieve-http-status-codes

Configuration
• Use a proxy server to capture the traffic from your
Selenium test(s)
• Find the status code for the action you’re interested
in (e.g., visiting a URL)
• Assert that the status code is what you expect

Blacklisting
http://elementalselenium.com/tips/66-blacklist

Configuration
• Use a proxy server to manipulate the traffic from
your Selenium test(s)
• Identify third-party resources that are slow to load
(which could negatively impact your tests)
• Blacklist them (e.g., make it so they don’t load)

Load Testing
http://elementalselenium.com/tips/68-load-testing-revisited

Configuration
• Use a proxy server to capture the traffic from your
Selenium test(s)
• Convert the HTTP Archive into a JMeter JMX file
• Run the new JMX file with JMeter to enact load on
your application (modify as needed)

https://flood.io/har2jmx

http://se.tips/selenium-to-jmeter

Broken Image Checking
http://elementalselenium.com/tips/67-broken-images

Option 1 - Proxy Server
Option 2 - HTTP Library
Option 3 - JavaScript

Option 1: Proxy Server

Option 1: Proxy Server

Option 1: Proxy Server

Option 2: HTTP Library

Option 2: HTTP Library

Option 2: HTTP Library

Option 3: JavaScript

Option 3: JavaScript

Option 3: JavaScript

Forgot Password
http://elementalselenium.com/tips/43-forgot-password

Configuration
• Use Selenium to trigger a forgot password workflow
(to an send to a real email address) and keep the
browser session active
• Retrieve the e-mail and the password information
via the email provider’s API
• Use the password information in the active
Selenium session (if applicable)

NOTE
- not free
- open issue

A/B Testing
http://elementalselenium.com/tips/12-opt-out-of-ab-tests

• 3 page states available
• You can identify which state you’re in because
there is different header text for each
• When you’re in the control: A/B Test Control
• For the variation: A/B Test Variation 1
• When you’re not in a test: No A/B Test
http://the-internet.herokuapp.com/abtest

Configuration
• You can easily opt-out of A/B tests by
• forging a cookie
• appending a query to the URL
• This way you get a known state of the page which
isn’t likely to change without your knowledge

File Management

Uploading a File
http://elementalselenium.com/tips/1-upload-a-file

Options
• GUI manipulation with something like AutoIt
• Input the file path into the form field (side-stepping
the system dialog)

http://se.tips/grid-file-upload

Downloading a File
http://elementalselenium.com/tips/2-download-a-file
http://elementalselenium.com/tips/8-download-a-file-revisited
http://elementalselenium.com/tips/15-download-secure-files

Two approaches
• Configure Selenium to download to local disk, and
delete the file when done
• Use an HTTP library, perform a HEAD request, and
check the headers for the correct content type &
length.
Why?
• An order of magnitude faster using Selenium
• No need to download the file

With Selenium

With Selenium

With an HTTP library

With an HTTP library

Additional Output

Highlight Elements
http://elementalselenium.com/tips/65-highlight-elements

Growl Notifications
http://elementalselenium.com/tips/53-growl

More Selenium Resources
• Selenium Bootcamp http://se.tips/se-bootcamp
• Weekly Selenium Tips http://se.tips/se-weekly-tips
• Weekly Se Tip Code http://se.tips/oss-tip-code
• Selenium Guidebook http://se.tips/se-guidebook

Available in Java and Ruby
(C#, Python, & JS coming soon!)
https://seleniumguidebook.com