Advanced Selenium Neal Ford 2

advanced selenium

NEAL FORD software architect / meme wrangler

ThoughtWorks®

nford@thoughtworks.com 3003 Summit Boulevard, Atlanta, GA 30319 www.nealford.com www.thoughtworks.com blog: memeagora.blogspot.com twitter: neal4d

Questions, Slides, and Samples

Please feel free to ask questions anytime

The slides and samples will be available at www.nealford.com

I’ll show that address again at the endSamples denoted via => document_name

What This Session Covers

Selenium’s scope

TestRunner techniques

Remote Control

Ajax

IDE

Extensions

Best practices

Selenium’s ScopeSelenium is an acceptance testing tool for web applications

Selenium tests are fragile by design

Selenium Test Runner Mode

Selenium Test

Runner

Selenium Core

Application

Under Test

The Selenium IDEFireFox extension

Not just a recorder

Intelligent field selection

Autocomplete for all common Selenium commands

Walk through tests

Debug and set breakpoints

String Matching Patterns

glob:patternMatch a string against a "glob" (aka "wildmat") pattern.

"*" represents any sequence of characters"?" represents any single character.

Glob patterns match against the entire string.regexp:regexp

Match a string using a regular-expression. The full power of JavaScript regular-expressions is available.

exact:stringMatch a string exactly, verbatim, without any of that fancy wildcard stuff.

If no pattern prefix is specified, Selenium assumes that it's a "glob" pattern.=> End 2 End Test

TestRunner Techniques

End-to-end Testing

Example of end to end testing => End 2 end Test

Always make sure you leave your application in a known good state

Generating Unique Values

The problem: you need unique user names

Solution: create user names based on time values

'fred ' + (new Date().getTime())

Data Driven TestsTest cases (and suites) don’t have to be static HTML

Verifying # of Rows in a TableAssert that nth row exists and that nth+1 does not

Use the assertXPath extension to count columns

assertElementPresent //table[@id='mytable']/tr[10]

assertElementNotPresent //table[@id='mytable']/tr[11]

assertXpath count(//table[@id='mytable']/tr) 10

Parameters and VariablesParameter and variable declarations range from simple values to Javascript evaluation

store, storeValue, and storeText store values for later access

Internally, Selenium uses a map called storedVars, keyed to variable names

store, storeValuestore( valueToStore, variableName )

Stores a value into a variable.

Variable substitution or javascript evaluation

storeValue( inputLocator, variableName )Stores the value of an input field into a variable.

storeText, storeAttributestoreText(elementLocator, variableName )

Stores the text of an element into a variable.

storeAttribute(elementLocator@attributeName, variableName)

Stores the value of an element attribute into a variable.

Variable SubstitutionProvides a simple way to access variables using ${xxx} syntax

JavaScript EvaluationYou can use JavaScript to construct whatever values you want

The entire parameter value is prefixed with ‘javascript{‘ with a trailing ‘}’

Text inside the braces is a pure JavaScript expression

Harvesting ValuesVariables allow you to harvest information from an “information only” page

Steps:

Build a page with values

On startup of the test, harvest those values

Use the variables for assertions in subsequent tests

=> harvesting values

Selenium Remote Control

Selenium Remote Control

JUnit Test

Proxy Server

Selenium Core

Application

Under Test

Interactive SeleniumStart the proxyCreate an instance of the browser

The proxy will provide a unique ID that must be used in all subsequent commandsYou’ll see a separate instance of the browser launch

Issue Selenium commandsWhen done, kill the browser instance=> Interactive Selenium

Test Code ReuseOne of the advantages of remote control

Create “helper” methods for common tasks

Login helper => DecisionDemo

When designing tests

Keep them modular

Refactor frequently

Multiple Language SupportThe Selenium IDE generates tests in a variety of languagesAll your tests don’t have to be in the same languageJava == Ruby example =>

Selenium Remote Control, Selenium Remote Control Ruby

Use the language that makes sense for the situation

DecisionsTestRunner tests can’t make deciscions

The Selenium language was designed to be strictly declarative, not imperative

In remote control, you write unit testsAllows you to make testing decisions

Firefox makes you logon, IE doesn’tDifferent roles for different users

Remote control gives you imperative tests in Selenium => Decision Demo

The Selenium IDEMore than just a pretty face!Supports multiple languages

TestRunner (declarative)Java, Ruby, C#, Python, etc. (imperative)

A round-trip tool……but only for declarative testsDon’t make the imperative plunge lightly

AjaxBecause Selenium works directly with the DOM, testing Ajax is easyTesting XmlHttpRequest =>Testing collapsable divs => End 2 End TestTesting absence of controls =>

Extending SeleniumSelenium allows you to add your own actions, checks, and locator strategies

Selenium uses naming patterns to discover extensions at run-time

ActionsAll methods in the form of doFoo are added as actionsFor each foo, and fooAndWait is created

ChecksAll assertFoo methods are added as checksFor each foo, you get assertFoo & verifyFoo

Locator StrategiesAll locateElementByFoo methods on PageBot are added as locator strategies

Locators take 2 parameters

Locator string (minus the prefix)

Document in which to search

Add a "valuerepeated=" locator, that finds the first element a value attribute equal to the the supplied value repeated.

Custom Locator

User ExtensionsBy default, Selenium looks for a file called "user-extensions.js", and loads the javascript code found in that file.

A convenient location for adding features to Selenium, without needing to modify the core Selenium sources.

This file doesn’t exist by default (you’ll have to add it)

Handy User ExtensionsAlert =>

Interactive debugger =>

GUI_Map =>

Allows you to handle auto-generated fields names more gracefully

Include =>

Check out http://wiki.openqa.org/display/SEL/Contributed+User-Extensions

Uploading FilesNormally, JavaScript permissions block you from filling in an input path for a file upload

Workaround:

Set the browser property “signed.applets.codebase_principal_support” to true

Add “netscape.security.PrivilegeManager.enablePrivilege(”UniversalFileRead”);” to selenium-api.js in function Selenium.prototype.doType

Currently only works in Firefox

Selenium Best PracticesCreate modular test methods for remote control

Allows for test code reuseEasier to refactorNot as fragile

Record acceptance testsEnd users/business analysts only have to verify it onceRegression tests catch errors

Selenium Best PracticesWrite selenium tests late in the development cycle

User acceptance tests are fragile

Require lots of refactoring

The danger is that you’ll stop running regression tests if they break too much

Questions?Please fill out the session evaluations

Samples & slides at www.nealford.com

This work is licensed under the Creative Commons Attribution-Noncommercial-Share Alike 2.5 License.

http://creativecommons.org/licenses/by-nc-sa/2.5/

NEAL FORD thoughtworker / meme wrangler

ThoughtWorks14 Wall St, Suite 2019, New York, NY 10005 nford@thoughtworks.comwww.nealford.comwww.thoughtworks.commemeagora.blogspot.com