Jan 14, 2015
Lecture Objective
Give students an introduction to web automation using the Selenium framework.
What is Selenium?
• Selenium is a web test tool that runs in the browser
• Because it runs in the browser, it does exactly what a user does
What tests can Selenium do?
• Browser compatibility – One script, many browsers
• Regression
Javascript
• Selenium is written in Javascript
• Javascript is how AJAX applications are written, so Selenium can test them too
Where to get it?
Selenium can be downloaded and installed for free from http://www.openqa.org
QTP vs. Selenium
• QTP is not cross platform, Selenium is• QTP costs a lot of money, Selenium is free• QTP needs VBScript, Selenium has lots of
language bindings• The default format of testing in Selenium is
HTML
• QTP can control other types of applications other than web
Multiple Seleniums?
There are 3 versions of Selenium
• Selenium Core – The main component of Selenium
• Selenium RC – A scripting layer over Selenium Core
• Selenium IDE – a Firefox extension with record / playback functionality
Selenium IDE
• Selenium IDE adds a layer of Record / Playback to Selenium
• Is available for Firefox only
First Script
Command Target Value
open /jobmining/
type queryTitle qa
select ct_category label=Banking
clickAndWait Submit01
clickAndWait link=sqa
Checkpoints
Of course, scripts wouldn’t be tests if they didn’t check something
• assert* tests fail the test immediately• verify* tests keep track of results and continue
the script regardless
verifyTextPresent Job Description \n dgds
asserTextPresent Job Requirements \n sdrfasf
Locators
Selenium identifies what a component is through the use of a locator
• link=name• dom=document.images[56]• xpath=//table[@id='table1']//tr[4]/td[2]• css=a[href="#id3"]
Depending on your application, there might be major performance differences
Playback
Playback of a single script is handled through the IDE
• Run – Go as fast as the script can process
• Walk – Slows down the execution
• Step – Executes the next step
Test Suites
In order to run multiple scripts, you need to chain them together in a Test Suite
• Just another html table
• Runs inside Firefox, but not in S-IDE
• Saved in the same directory as the tests that are included in it
Test Suites
<table> <tr> <td>Job Search test suite</td> </tr> <tr> <td><a target="testFrame" href=“selenium-ide-
01.html">Job Search</a></td> </tr></table>
Test Suites
The URL has a specific format
chrome://selenium-ide/content/selenium/TestRunner.html?baseURL=http://your_hose:port&test=file:///c://temp/qa109/testsuite.html&auto=true&multiWindow=false
Selenium RC
Selenium IDE is great for quick recording of tests, but it somewhat lacks for power
Selenium RC gives you the ability to drive Selenium from a real programming language (Java, Perl, Python, Ruby, and more)
Why do you want a real language?
By using Selenium inside a full fledged language you can do the following
• Seed the database• Check the database• Control external services• Launch multiple windows• Run multiple browsers in parallelIn addition to running the actual test.
Proxy
Because the commands for Selenium RC are embedded in a script, a proxy is needed to control the browser.
Python
There are python bindings for most of the Selenium calls
• Watch for naming differences
• While not necessary, most use the unittest module with Selenium
import selenium, unittest
class JM(unittest.TestCase):
def setUp(self):
protocol = "http"
host = "your host"
port = your_port_number
self.verificationErrors = []
self.selenium = selenium.selenium("localhost", 4444, "*chrome", "%s://%s:%s" % (protocol, host, port)) self.selenium.start()
self.selenium.open("/jobmining/")
def test_doSearch(self):
sel = self.selenium
sel.open("/jobmining/")
sel.type("queryTitle", "qa")
sel.select("ct_category", "label=Banking")
sel.click("Submit01")
sel.wait_for_page_to_load("30000")
sel.click("link=sqa")
sel.wait_for_page_to_load("30000")
try:
self.failUnless(sel.is_text_present("Job Description \n dgds"))
except AssertionError, e:
self.verificationErrors.append(str(e))
def tearDown(self):
self.selenium.stop()
if __name__ == "__main__":
unittest.main()
Data Driven
• One key concept when doing automation is to recycle your scripts through data driving them
• Use the underlying language you are using Selenium RC with to handle most of it for you
Same Origin
Prevents a document or script loaded from one origin from getting or setting properties of a document from a different origin – Mozilla security documentation
In other words, cannot work across server boundries
Selenium Core
• Selenium Core is used by both Selenium IDE and RC
• Runs test suites on the same server to avoid the Same Origin problem
• Don’t have same flexibility as RC, but tests and code under test is in the same spot
Tips
• Start and stop your script from the same spot
• Record your script in S-IDE, then use it as a base for a S-RC script
• Use Firebug to give you the XPath
Designing for Selenium
• Proper use of tables and CSS div tags makes Selenium much easier
Support
Because this is free, open source software there is no official support channel
• Mailing lists• Wiki• ForumsAre your main sources of assistence.
But don’t forget your peers!