Selenium – Beyond the Page Object Pattern By: Sam Woods - Webtrends

Who Am I? Senior SDET at Webtrends for over a year. Heading up automation efforts including infrastructure, frameworks, processes, continuous integration, logging and reporting, etc. QA/SDET at Microsoft for 13 years. Evolved from manual testing and test planning to automation and finally development of automation infrastructure for the Windows Live organization. Primary developer of a web UI automation framework for 5+ years that was used by all of Windows Live and throughout the company.

Who is Webtrends? Webtrends powers digital marketing success. Webtrends is at the forefront of real-time digital marketing relevance and customer experience management through unified customer intelligence. Our industry-leading analytics across mobile, social and web enables marketers to optimize campaigns, maximize customer lifetime value and deliver highly relevant digital brand experiences in real time. Webtrends dramatically improves digital marketing results for more than 3,500 global brands including: The New York Times, Microsoft, BMW, RIM, China Telecom, China Mobile, CCTV, Tencent QQ, Hitachi, The Associated Press, HSBC, Barclays, Vivo Cellular and Petrobras.

How Does Webtrends Use Selenium? Selenium is currently used to test 2 distinct products. Analytics – reporting web site with a number of different report types for different content types (web, mobile, social, etc). Segments – web application used to create user “segments” and perform queries based on those segments and attributes. This is truly a “web app”. It is a single dynamic page with thousands of elements and a “canvas” to create visual representations of data that heavily relies on drag and drop.

History of the Page Object Pattern Created a base class called “PageObject” to programmatically enforce some best practices I had been using in my own automation. Also documented some rules and processes to follow when creating UI automation. Presented the concept to a number of audiences including to over 300 Microsoft Employees at an Engineering Excellence and Trustworthy Computing Forum. After leaving Microsoft, found that the Selenium community had begun standardizing on a “Page Object Pattern” that was strikingly similar. While at Microsoft I became a big advocate of shifting the mindset from “test scripts” to using object oriented programming techniques to decrease the amount of time it took to create and maintain automation.

The Evolution of (my) UI Automation Test Scripts > Remove Sleeps > Add Logging and Comments > Move retries and logging to abstraction > Move common startup code to xUnit startup class > Move elements to Page classes > Create logical helper functions in the page classes > Create common data classes to drive tests

DEMO TIME!

UI Automation Rules Never EVER sleep. Test cases should only access page class members, Page Class should only access abstraction layer, abstraction layer should only access selenium. Identify elements by ID if possible. Avoid identifying elements by text. Avoid identifying elements by xpath (or other means) that include parent or ancestor elements. Unless including a parent or ancestor can speed up searching for the element. Validation functions should return bool and the test case should assert.

Page Object Pattern (POP) VS My Solution

Exists in POP and not in my Solution Methods return other PageObjects. I don’t like this since depending on the data I enter into a form I may be taken to any number of pages including staying on the same page. Different results for the same action are modeled as different methods. I prefer a single method that I can execute and then call a validation method depending on the data I passed into the helper. PageFactory This is unnecessary since my abstraction uses lazy initialization for all elements.

Exists in my Solution and not in POP Static class containing all pages and helper functions that can span multiple pages. Base page class with Navigate function and ValidateLocation function

Abstraction Layer Goodness

Lazy Initialization Create an instance of an element object but doesn’t search for the element on the page until first use (execute a method or access a property) No need for PageFactory. No need using POP to create a new function for one simple action such as a click to a single element. Takes care of ensuring an element exists and is visible upon initialization. Mostly avoids StaleElementException.

Strongly Typed Element Objects Rather than a single IWebElement class, there is a Button, Link, Textbox, etc class. Finds elements faster (based on tag name) Avoids conflicts if multiple elements with different tag names match the element identifier. Able to trust intellisense since only methods/properties available for the specific element type show up. Easy to tell from the code what type of element you’re working with.

Get(related) functions GetParent, GetChild, GetChildren, GetDescendant, GetDescendants. Simplifies getting related elements Want to add GetSibling, GetSiblings, GetAncestor Speeds up finding elements on large pages if you set an AncestorElement as a property of any element. One caveat, this can only be executed after already navigating to the page containing the elements, no lazy initialization (can’t call it in your page object constructor)

Automatic Polling Searches to ensure an element exists and is visible before performing each action. MaxRetries and WaitBetweenRetries can be set globally or for a specific element, or use the defaults. Avoids most timing related issues due to pages not finished loading. Mostly makes logic to wait until a page is displayed unnecessary.

Miscellaneous Goodness Built in logging Built in creation of “ElementIdentifier” for logging. Find elements by any attribute or combination of attributes with exact match or partial match. DragAndDrop functions (using Actions class). Get innertext that is not visible (Selenium “feature”). Automatically switch to most recently opened window (handle links with “target” defined). Easily define iframe name or index to look for element in, or search in all iframes recursively. Click with offset

What’s Next? Releasing abstraction layer as an open source project to the community.

Questions?

Info/Resources http://sqa.stackexchange.com I participate here and there are a number of other people who can answer Selenium questions as well. E-mail: samwoo111@hotmail.com

Jobs at Webtrends http://jobvite.com/m?3lH1mfw9