Automated Web Testing with Selenium

By Jodie MinersPresented to SBTUG30 September 2009

What is Selenium? It’s Free and Open Source It originally came from Thoughtworks It comes in 3 flavours

› IDE (Integrated Development Environment) – for recording test cases in Firefox

› RC (Remote Control) – for running automated tests on any browser

› Grid – for large scale test runs of multiple tests in parallel

You can get it here http://www.seleniumhq.org/ “Selenium tests run directly in a browser, just as

real users do”

Why use Selenium You are always doing the same steps

over and over again You need to get to the last step in a

wizard to test that step You want to pre-fill some dummy data Formal Functional and Regression

Testing Load Testing *

Selenium IDE A Firefox add-on that allows you to record

tests for playing back in any browser. Very simple to use Allows non developers to get up and

running with automated testing very quickly› Then they can pass on to developers for

refinement or inclusion into a continuous build system

Can extend it easily with a little bit of HTML knowledge

Recording and Playback

First Decide what you are testing and work out your test case(s)

IDE Demo› Record a test› Play back a test› Debug a test› Step through a test› Capture screen shot› Asserts

Selenese The language of selenium. It is quite easy to learn 3 parts to it

› Command – eg Type› Locator – eg Input Box› Value – eg “ABC”

Can easily be written in HTML Things to help build the IDE tests

› Assert / Wait for Page to Load / Verify Text Present / Verify element present on each page

› Slow things down with pauses and timeouts› Step through firs then run, add pauses and wait’s if it fails

because it’s going too fast› Add think times

Selenese Locators Can Locate page elements by the following 4

methods› ID, DOM, Xpath, CSS

IDE recorder will choose the best one to use, or you can choose which ever method if you are coding the tests.

Can also use Wildcards and Regular Expressions See

http://seleniumhq.org/docs/04_selenese_commands.html for more info - it’s very comprehensive

Install Firebug to help with working out the locators

Selenium RC Takes a little time and effort to get it up and

running Can then run your tests scripts from IDE in

different browsers› With good results reporting

Or write the tests in code and automate the testing even further

Issues› Need to Install and use Java› Very command line / batch file based

Selenium RC Demo

Coding your tests Coding of Selenium testing can be done in

› Java, Ruby, Groovy, C#, Perl, PHP, Python› Most examples are Java or Ruby, not that many people using C#

Add If statements› Eg if stock exists then add to cart (rather than having an error

message) Add looping statements

› For each product found, add to cart Easier to add parameterisation or data driven tests

› eg have a list of products in a file or table – add each of the products to the cart

› (you can do data driven tests in IDE – see here http://wiki.openqa.org/display/SEL/datadriven )

Multiple test runs› Run the test 4 times, each time logged in as a different user

Selenium Code Demo with NUnit

Reporting There is a great reporting framework if you code in

Java or use TestNG› Logging Selenium http://loggingselenium.sourceforge.net/

For C# these are the options: › Just capture the Selenium output to a file› Code a reporting framework yourself› Use the Visual Studio Team System Test Edition framework› Use the NUnit reporting

I use a combination of VSTT reporting and some additional logging to a database that I created myself.

Selenium Grid Scale out the tests to run on multiple

browsers at the same time Saves time in doing the testing

› But you need to rely on the reporting as you can’t watch 5+ browsers do the testing

Great tutorial and demo here http://selenium-grid.seleniumhq.org/

Requires Java SDK and Apache Ant to run

My Grid SetupSelenium

HubMy Laptop

Agent 1My Laptop

Agent 2Spare Dev

PC

Web SiteWeb Server

Reporting Database

Dev Database

Agent 3Spare

Server

Test Runner mstestDev Server

Parameter Database

Database Server

Taking the Grid Further Scale out your grid to the Cloud using Amazon EC2 service Or use a third party service

› Sauce Labs http://www.saucelabs.com In early beta Uses your own code

So can set up the code to either run locally or via web Current special US$100 for 5000 minutes Lots of Browser / OS combinations Test Environment Picture

› BrowserMob http://www.browsermob.com Time consuming to set up Some limitations on which selenium commands can be used Lots of options (eg can test with specific bandwidth limitations) Can be used as for http requests only, as well as real browser tests Around US$2.00 per browser per hour

More Advanced Topics UI Element mapping – How developers

can make it easier for end users to build Selenium tests using element locator names that they can understand› http://ttwhy.org/home/blog/2007/05/12/sele

nium-ui-element-locator/

Using Xpath references with the Ext-JS javascript framework › http://www.xeolabs.com/portal/node/34

Load Testing Purists say Selenium is not for load testing That is mainly because of the hardware required

to run multiple browsers on the same machine.› I hit limits of 5-8 browsers on a standard desktop

machine and 12-15 browsers on a server› Use Browser Mob or SauceLabs to overcome these

issues. Also as Selenium uses Real Browsers it requires

real logins to simulate real loads – so you have to log in as real users on your system› It does not do virtual load and virtual users

Recording in IE (just for @aussienick)

Watin for .net › http://watin.sourceforge.net/ › Has a built in recorder for IE› There are also Watir (ruby), and Watij (java) variants

http://wtr.rubyforge.org/ Visual Studio Team System 2008 Test Edition

(VSTT) Visual Studio Team System 2010 Test Edition +

Team Foundation Server› Looks Fantastic› Will also record and play back windows apps› Must use TFS

References

Selenium Tutorial http://dynamitemap.com/selenium/ including a good video

Full list of software testing tools http://www.softwareqatest.com/qatweb1.html

VSTT Quick Reference http://vstt2008qrg.codeplex.com/

X-Path References There is a great deal of help online for Xpath, here are some

of the best sites I’ve found Xpath reference

http://www.w3schools.com/Xpath/default.asp Some nice simple examples (on the Xpath tab)

http://confluence.sakaiproject.org/display/QA/Selenium Quick Reference Card

http://confluence.sakaiproject.org/display/QA/Selenium MSDN

http://msdn.microsoft.com/en-us/library/ms256115.aspx Great tutorial with lots of examples

http://www.zvon.org/xxl/XPathTutorial/General/examples.html Selenium Wiki Xpath reference

http://wiki.openqa.org/display/SEL/Help+With+XPath