CSharp

Boa Constrictor’s Awesome Hacktoberfest 2021

Boa Constrictor is the .NET Screenplay Pattern. It helps you make better interactions for better automation! Its primary use case is Web UI and REST API test automation, but it can be used to automate any kind of interactions. The Screenplay Pattern is much more scalable for development and execution than the Page Object Model.

The Boa Constrictor maintainers and I strongly support open source software. That’s why we participated in Hacktoberfest 2021. In fact, this was the second Hacktoberfest we did. We launched Boa Constrictor as an open source project a year ago during Hacktoberfest 2020! We love sharing our code with the community and inspiring others to get involved. To encourage participation this year, we added the “hacktoberfest” label to open issues, and we offered cool stickers to anyone who contributed.

Boa Constrictor sticker
Boa Constrictor: The .NET Screenplay Pattern
Sticker Medallion

Hacktoberfest 2021 was a tremendous success for Boa Constrictor. Even though the project is small, we received several contributions. Here’s a summary of all the new stuff we added to Boa Constrictor:

  • Updated WebDriver interactions to use Selenium WebDriver 4.0
  • Implemented asynchronous programming for Tasks and Questions
  • Extended the Wait Task to wait for multiple Questions using AND and OR logic
  • Standardized ToString methods for all WebDriver interactions
  • Automated unit tests for WebDriver Questions
  • Wrote new user guides for test framework integrations and interaction patterns
  • Made small refinements to the doc site
  • Created GitHub templates for issues and pull requests
  • Replaced the symbols NuGet package with embedded debugging
  • Added the README to the NuGet package
  • Added Shields to the README
  • Restructured projects for docs, logos, and talk

During Hacktoberfest 2021, we made a series of four releases because we believe in lean development that puts new features in the hands of developers ASAP. The final capstone release was version 2.0.0: a culmination of all Hacktoberfest work! Here’s a view of the Boa Constrictor NuGet package with its new README (Shields included):

The Boa Constrictor NuGet package with the new README and Shields
The Boa Constrictor NuGet package with the new README and Shields

If you like project stats, then here’s a breakdown of the contributions by numbers:

  • 11 total contributors (5 submitting more than one pull request)
  • 41 pull requests closed
  • 151 commits made
  • Over 10K new lines of code

GitHub’s Code Frequency graph for Boa Constrictor shown below illustrates how much activity the project had during Hacktoberfest 2021. Notice the huge green and red spikes on the right side of the chart corresponding to the month of October 2021. That’s a lot of activity!

Hacktoberfest Contributions
The GitHub Code Frequency Graph for Boa Constrictor

Furthermore, every member of my Test Engineering & Architecture (TEA) team at Q2 completed four pull requests for Hacktoberfest, thus earning our prizes and our bragging rights. For the three others on the team, this was their first Hacktoberfest, and Boa Constrictor was their first open source project. We all joined together to make Boa Constrictor better for everyone. I’m very proud of each of them individually and of our team as a whole.

Personally, I gained more experience as an open source project maintainer. I brainstormed ideas with my team, assigned work to volunteers, and provided reviews for pull requests. I also had to handle slightly awkward situations, like politely turning down pull requests that could not be accepted. Thankfully, the project had very little spam, but we did have many potential contributors request to work on issues but then essentially disappear after being assigned. That made me appreciate the folks who did complete their pull requests even more.

Overall, Hacktoberfest 2021 was a great success for Boa Constrictor. We added several new features, docs, and quality-of-life improvements to the project. We also got people excited about open source contributions. Many thanks to Digital Ocean, Appwrite, Intel, and DeepSource for sponsoring Hacktoberfest 2021. Also, special thanks to Digital Ocean for featuring Boa Constrictor in their Hacktoberfest kickoff event. Keep on hacking!

Boa Constrictor is doing Hacktoberfest 2021!

Boa Constrictor is the .NET Screenplay Pattern. It helps you make better interactions for better automation! Its primary use case is Web UI and REST API test automation, but it can be used to automate any kind of interactions. The Screenplay Pattern is much more scalable for development and execution than the Page Object Model.

My team and I at Q2 developed Boa Constrictor for testing the PrecisionLender web app. Originally, we developed it internally as part of our C# test automation solution named “Boa”, but we later released it as an open source project on GitHub so that others could use it. In fact, we released it publicly in October 2020 during last year’s Hacktoberfest!

We are delighted to announce that Boa Constrictor will participate in Hacktoberfest 2021. Open source software is vital for our industry, and we strongly support efforts like Hacktoberfest to encourage folks to contribute to open source projects. Many thanks to Digital Ocean, Appwrite, Intel, and DeepSource for sponsoring Hacktoberfest again this year.

So, how can you contribute to Boa Constrictor? Take these four easy steps:

  1. Start by learning about the project.
  2. Read our guide to contributing code.
  3. Clone the GitHub repository.
  4. Look for unassigned open issues labeled “hacktoberfest”.
    1. Or, open an issue to propose a new idea!
  5. Add a comment to the issue saying that you’d like to do it.

To encourage contributions, I will give free Boa Constrictor stickers to anyone who makes a valid pull request to the project during Hacktoberfest 2021! (I’ll share a link where you can privately share your mailing address. I’ll mail stickers anywhere in the world – not just inside the United States.) The sticker is a 2″ medallion that looks like this:

Boa Constrictor sticker
The Boa Constrictor Sticker

Remember, you have until October 31 to make four qualifying pull requests for Hacktoberfest. We’d love for you to make at least one of those pull requests for Boa Constrictor.

Announcing Boa Constrictor Docs!

Doc site:
https://q2ebanking.github.io/boa-constrictor/

Boa Constrictor is a C# implementation of the Screenplay Pattern. My team and I at PrecisionLender, a Q2 Company, developed Boa Constrictor as part of our test automation solution. Its primary use case is Web UI and REST API test automation. Boa Constrictor helps you make better interactions for better automation!

Our team released Boa Constrictor as an open source project on GitHub in October 2020. This week, we published a full documentation site for Boa Constrictor. They include an introduction to the Screenplay Pattern, a quick-start guide, a full tutorial, and ways to contribute to the project. The doc site itself uses GitHub Pages, Jekyll, and Minimal Mistakes.

Our team hopes that the docs help you with testing and automation. Enjoy!

Using Multiple Test Frameworks Simultaneously

Someone recently asked me the following question, which I’ve paraphrased for better context:

Is it good practice to use multiple test frameworks simultaneously? For example, I’m working on a Python project. I want to do BDD with behave for feature testing, but pytest would be better for unit testing. Can I use both? If so, how should I structure my project(s)?

The short answer: Yes, you should use the right frameworks for the right needs. Using more than one test framework is typically not difficult to set up. Let’s dig into this.

The F-word

I despise the F-word – “framework.” Within the test automation space, people use the word “framework” to refer to different things. Is the “framework” only the test package like pytest or JUnit? Does it include the tests themselves? Does it refer to automation tools like Selenium WebDriver?

For clarity, I prefer to use two different terms: “framework” and “solution.” A test framework is software package that lets programmers write tests as methods or functions, run the tests, and report the results. A test solution is a software implementation for a testing problem. It typically includes frameworks, tools, and test cases. To me, a framework is narrow, but a solution is comprehensive.

The original question used the word “framework,” but I think it should be answered in terms of solutions. There are two potential solutions at hand: one for unit tests written in pytest, while another for feature tests written in behave.

One Size Does Not Fit All

Always use the right tools or frameworks for the right needs. Unit tests and feature tests are fundamentally different. Unit tests directly access internal functions and methods in product code, whereas feature tests interact with live versions of the product as an external user or caller. Thus, they need different kinds of testing solutions, which most likely will require different tools and frameworks.

For example, behave is a BDD framework for Python. Programmers write test cases in plain-language Gherkin with step definitions as Python functions. Gherkin test cases are intuitively readable and understandable, which makes them great for testing high-level behaviors like interacting with a Web page. However, BDD frameworks add complexity that hampers unit test development. Unit tests are inherently “code-y” and low-level because they directly call product code. The pytest framework would be a better choice for unit testing. Conversely, feature tests could be written using raw pytest, but behave provides a more natural structure for describing features. Hence, separate solutions for different test types would be ideal.

Same or Separate Repositories?

If more than one test solution is appropriate for a given software project, the next question is where to put the test code. Should all test code go into the same repository as the product code, or should they go into separate repositories? Unfortunately, there is no universally correct answer. Here are some factors to consider.

Unit tests should always be located in the same repository as the product code they test. Unit tests directly depend upon the product code. They mus be written in the same language. Any time the product code is refactored, unit tests must be updated.

Feature tests can be placed in the same repository or a separate repository. I recommend putting feature tests in the same repository as product code if feature tests are written in the same language as the product code and if all the product code under test is located in the same repository. That way, tests are version-controlled together with the product under test. Otherwise, I recommend putting feature tests in their own separate repository. Mixed language repositories can be confusing to maintain, and version control must be handled differently with multi-repository products.

Same Repository Structure

One test solution in one repository is easy to set up, but multiple test solutions in one repository can be tricky. Thankfully, it’s not impossible. Project structure ultimately depends upon the language. Regardless of language, I recommend separating concerns. A repository should have clearly separate spaces (e.g., subdirectories) for product code and test code. Test code should be further divided by test types and then coverage areas. Testers should be able to run specific tests using convenient filters.

Here are ways to handle multiple test solutions in a few different languages:

  • In Python, project structure is fairly flexible. Conventionally, all tests belong under a top-level directory named “tests.” Subdirectories may be added thereunder, such as “unit” and “feature”. Frameworks like pytest and behave can take search paths so they run the proper tests. Furthermore, if using pytest-bdd instead of behave, pytest can use the markings/tags instead of search paths for filtering tests.
  • In .NET (like C#), the terms “project” and “solution” have special meanings. A .NET project is a collection of code that is built into one artifact. A .NET solution is a collection of projects that interrelate. Typically, the best practice in .NET would be to create a separate project for each test type/suite within the same .NET solution. I have personally set up a .NET solution that included separate projects for NUnit unit tests and SpecFlow feature tests.
  • In Java, project structure depends upon the project’s build automation tool. Most Java projects seem to use Maven or Gradle. In Maven’s Standard Directory Layout, tests belong under “src/test”. Different test types can be placed under separate packages there. The POM might need some extra configuration to run tests at different build phases.
  • In JavaScript, test placement depends heavily upon the project type. For example, Angular creates separate directories for unit tests using Jasmine and end-to-end tests using Protractor when initializing a new project.

Do What’s Best

Different test tools and frameworks meet different needs. No single one can solve all problems. Make sure to use the right tools for the problems at hand. Don’t force yourself to use the wrong thing simply because it is already used elsewhere.

WebDriver Element Existence vs. Appearance

Web UI tests with Selenium WebDriver must interact with elements on a Web page. Locating elements can be tricky because expected elements may or may not be on the page. Furthermore, WebDriver might not be able to interact with some elements that exist on the page. That may seem crazy, but let’s understand why.

Web UI interactions universally follow these steps:

  1. Wait for an element to be ready.
  2. Get the element using a locator (ID, CSS selector, XPath, etc.).
  3. Send commands (like clicking or typing) or queries (like getting text) to the element.

Clearly, an element must be “ready” before interactions can happen. As humans, we intuitively define “ready” as, “The page is loaded, and the element is visible.” Automation code is a bit more technical because there are two different ways to define readiness:

  1. Existence: the element exists in the HTML structure of the page.
  2. Appearance: the element exists and it is visible on the page.

Existence can easily be determined by WebDriver’s “find elements” method. The plural “find elements” method will return a list of all elements matching a locator query. If no elements match the locator, then an empty list is returned. The singular “find element” method, on the other hand, will return the first element matching the locator or throw an exception if no elements are found. Thus, the plural version is more convenient to use for checking existence.

Here’s an example existence method in C#:

public bool Exists(IWebDriver driver, By locator) =>
    driver.FindElements(locator).Count > 0;

Checking for existence is the most basic level of readiness. If an element doesn’t exist, interactions with it simply cannot happen. However, existence alone may not be sufficient for interactions. Selenium WebDriver requires elements to not only exist but also to be displayed for interactions like sending clicks and scraping text. Existing elements may be scrolled out of view or even deliberately hidden. WebDriver calls to such elements will yield cryptic exceptions. That’s why waiting for appearance is usually the better readiness condition.

Here’s an example appearance method in C#:

// Assume that the locator targets one element, not multiple
public bool Appears(IWebDriver driver, By locator) =>
    Exists(driver, locator) && driver.FindElement(locator).Displayed;

Existence must be checked first, or else the “Displayed” call will throw an exception whenever existence is false.

Putting it all together, here’s what a button click interaction could look like in C#:

// Assume this is a method in a Page Object class
// Assume that "Driver" is the WebDriver instance
public void ClickThatButton()
{
    var button = By.Id("that-button");
    var wait = new WebDriverWait(Driver, new System.Timespan(0, 0, 15));
    wait.Until((driver) => Appears(driver, button));
    Driver.FindElement(button).Click();
}

It’s good practice to make explicit waits before locating and using elements. It’s also good practice to get fresh elements for every interaction call in order to avoid pesky stale element exceptions. Calls like these should be placed in Page Object methods or Screenplay Pattern tasks and questions so that interactions are safe and thorough.

Appearance may not always be the right choice. There may be times when a test should check if an element doesn’t exist or if an element exists but is hidden. Just think before you code.