When crafting Automation frameworks, do you use SOLID Software design principles in your work? If so, could you provide some examples?  

Ever since I've been tasked to create a Capybara + Ruby UI automation framework, I've been reading  books such as Robert "Uncle Bob" C. Martin's Clean Architecture: A Craftman's Guide to Software Structure and Design (2018) and his Agile Software Development, Principles, Patterns, and Practices (2002), trying to glean some insight on how to improve what I am doing.

The SOLID object oriented design principles, a mnemonic created by Michael Feathers based on principles Uncle Bob had collected are a bit beyond me at the moment. Attempting to study about the Single responsibility principle, Open/closed principle, Liskov substitution principle, Interface segregation principle and the Dependency inversion principle, trying to see how I can apply them is giving me a headache.

I fully recommend Angie Jones' webinar, Applying the Pillars of Object Oriented Frameworks to Test Automation for anyone who needs a refresher on Encapsulation, Inheritance, Polymorphic and Abstraction. I wish there was something like this for SOLID design principles!

Here are some of the principles I follow when writing automation frameworks:

DRY

• Don't Repeat Yourself.  Instead of copying-and-pasting code, I factor out commonly used code snippets, placing the block of code into a library I can then reuse. 

YAGNI

• You Ain't Going To Need It. Instead of plotting out every single selector on a page that locates a web element in a user-interface, I focus on just what I need for the current two week sprint. Every single time I try to plan ahead, priorities change, shift, reshape, and by the time I finally get back to the prepwork, everything has changed.

Abstraction

• If there is a Login screen, I create a Login page object, which stores all the locators that interact with the web elements such as the username & password textbox, and the Login button. It also would have a LOGIN method where a test could pass in a username and password and be logged into the System Under Test.

Encapsulation

• Within Page Objects, I declare public methods that then interact with the private variables storing the selectors for the web elements on the page. 

Inheritance

• Are there commonly used elements on the page? I create a Base Page Object which contain commonly used methods that other pages can inherit.

These principles? I find them easy to understand and use. SOLID Principles? Not so much.

Any help that you could give would be much appreciated. I will craft a response blog post from the answers I receive. 

Oh, and don't get me started on how lost I am about the Gang of Four's Design Patterns: Elements of Reusable Object-Oriented Software (1994)!



Happy Testing?

-T.J. Maher
Sr. QA Engineer, Software Engineer in Test
Meetup Organizer, Ministry of Testing - Boston

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