Using Modular and Data-Driven Design Patterns for e2e Testing

Automated test tools are used primarily to reduce the time and cost of an application’s testing process by eliminating the need for extensive manual software testing. Just like in the End-to-End Testing method, design patterns play an important role. Design patterns can change the way we solve problems, almost like idioms in a language. They help us think about the structure of our applications and shape their long-term development.

Test automation is an interesting topic to consider when talking about design patterns since it is often used to increase production standards or the quality of software. In test automation, the design pattern makes it even more vast as it is a procedure used to solve a complex problem. As well-defined systems, design patterns can reduce development time and resources, as well as provide a greater likelihood that the needs of all parties are explicitly taken into consideration during the implementation process. Furthermore, when designing software for test automation, a test architect and an automation engineer should choose the same framework to ensure code consistency. Thus, the design patterns can be more useful when building a framework in smaller projects that are loosely coupled.

Introduction to End-to-End Testing


End-to-end testing is an approach to testing an integrated software system by simulating the activities of one or more of its users. Such tests, if well-designed, are likely to involve an entire sequence of events from start to completion, including and especially those parts of the process where there is considerable potential for failure. In a nutshell, E2E testing refers to the concept of testing a complete transaction such as buying an airline ticket or adding ingredients to a shopping cart. The test verifies the right output given the right input. E2E tests are always recorded and played back with different inputs. They can be mocked, but the intent is not to test function calls but to test visual components. A user interface is considered tested only when all possible pathways through the application have been tested. In a good E2E testing strategy, the QA team can look at every single feature available online and tell whether it works correctly or not. The success of an application is no longer determined by how many new features can be put in place. Instead, it’s determined by how quickly bugs can be identified and fixed. Developers want to get rid of bugs as soon as possible since doing so can reduce the risk of losing users to competitors.

Working with Design Patterns


Test automation is the application of testing to an application under test in order to achieve its regression toward an earlier known good state. This can be done to show that the software is working correctly or to show compliance with specifications. Most testing in production environments takes automated tests as the base reality and scope are limited by coding standards and code coverage. Test architectures are required for this type of testing with more than single coverage because a different truth table, sequence of events, or regulatory requirements dictate another baseline.

  • A design pattern is a solution to a problem; a general reusable solution to a common problem in software design. The purpose of the patterns is to describe recurring solutions to problems in object-oriented design, especially in user interface programming and graphical user interfaces (GUIs).
  • Design patterns help reusable platforms not be locked into one solution but to be concerned with how something works from general use rather than how a specific instance functions, helps in the quick and easy development of the common architecture for solutions for new features as well as new applications.
  • They are a way of documenting frequently occurring solutions to common problems in software development. These solutions have been found to be flexible enough to be adapted over time and across several languages, hence very useful in designing software.

To be precise, these patterns can be used as guidelines for problem-solving when building an application, also like any other best practice in writing software code. Design patterns help make code easier to understand, even for another developer attempting to work on the same code.

Modular Design Patterns

For rapid test development, modular test modules should be designed from the start to require as little primary programming effort as possible. Most likely, this means developing them as independent scripts, but with a uniform naming convention and directory structure that allows the developer to effortlessly add these modules to existing or new scripts while maintaining a consistent structure.

  • To be precise, modular testing is a design pattern for developing and writing tests for complex software systems. It is an elegant answer to the complexity faced when writing and maintaining tests for objects that interact with each other, such as drivers and services, which can throw errors and exceptions.
  • Modular Testing tightly couples small test cases together through the hierarchy. Since these short scripts are easy to read, readability improves. The idea of the module is to compartmentalize the tests into separate sections. This would require single specific purpose objects, each with clear-cut functionality, that can be easily reused.
  • One of the primary benefits of modular testing is its ability to reduce dependencies in the design. The side effect of this benefit is reducing the number of files required for a given program. However, as applications grow larger and larger, managing all these files can become a huge detriment to your productivity as a programmer. In an attempt to retain the overall usefulness of structured programming without the clutter of boilerplate code, it is common practice to break up a program into separate, independent pieces (“modules”). As these modules grow in complexity and number, they increase the likelihood of bugs being introduced into the system while at the same time making it more difficult to keep track of what’s going on and where errors may reside.

Precisely, the most important part of choosing a modular design pattern for your tests is deciding which modules are needed to cover the functionality and features of your AUT.

Data-Driven Design Patterns

The data-driven design is a method used to structure a program into an abstract model and a collection of units that are plug & play. The data-driven design seems to have emerged as a popular strategy since the rise of web computing as a widespread phenomenon with the potential of raising the addiction quotient of users.

  • Data-driven design can be a real paradigm shift for programmers who are used to writing code in the traditional way. The goal of it is to get rid of all or most of the code that you typically write. In its place, you need to replace it with data in meta-syntax format. This can be as simple as using properties or classes other than private attributes, but even that can lead to a lot of unnecessary confusion for many people.
  • These units represent actions that can be triggered by various events and also produce messages, either to the user or other units for handling. The main benefit of this paradigm is that it ensures rapid turnaround for new feature development.
  • The principle behind the data-driven design is that systems should be built from the bottom up as opposed to being detailed from the top down or being created as carbon copies of one another with only variables changed.

This design pattern is mostly a way of ensuring that assertions and assumptions are made clear in the code by means of comments, through the judicious use of constants and enumerations, or through the use of flags.

Advantages of Design Patterns


Design patterns are very useful in the software development process. The core principle behind these design patterns is that we can decrease the cost of maintenance by not having to reinvent the wheel. Design patterns solve the problem at the code level and at the same time support our process. Furthermore, the advantages associated with the design patterns are:

  • With the advent of object-oriented programming some of the common design patterns have been evolved. It has provided a structured approach to resolve the software design. Design Patterns have been used in automated testing for various purposes.
  • They are reusable and predictable solutions to common problems in software design. Using design patterns help us in writing code that is less error-prone, and easy to maintain, change etc.
  • Design patterns are basically a blueprint or prototype that helps in solving the similar problems in architectural design. The main benefits of using design patterns in software engineering is code reusability, improves readability of code, enhances the design flexibility and maintainability.
  • In addition to the technical aspect of design patterns, it also helps in improving communication between the development and the testing departments.
  • Programmers use patterns to design the modules in their software applications whereas testers can make use of patterns to design test cases which would ensure effectiveness as well as the speed of testing.

Design Patterns are a powerful way of solving problems and documenting them at the same time. In test automation, design patterns help in creating reusable test cases which do not duplicate code. Clearly, the goal of automation should be not just to automate your tests but to enable as many people as possible, such as product managers and testers, to provide valuable input and feedback.

Wrapping Up


Automation is not only the process of testing your products, it also provides a platform for your software development teams to accomplish many things in a short period of time and lets you provide maximum value to your customers. For automation, design patterns play an important role because of the way they have been designed to help the developers. Design patterns have been around in software engineering for some time now. But there is a greater emphasis on test automation design patterns today. One reason is that there has been a move from manual testing to test automation in the software industry over the years. Before automation engineers can design a test automation framework, they must first understand all available design options for their framework and similar frameworks. You can rely on LambdaTest for all your end-to-end testing needs. The cross-browser testing platform provides both exploratory and automated testing across 3000+ different browsers, real devices and operating systems. You can run Selenium, Cypress, Appium, Hyperexecute, Playwright and Puppeteer tests at scale with the platform. Not only this, LambdaTest is absolutely free to sign up with.