End-to-End Testing: The Ultimate Guide for Agile Teams | Agilitest blog
Software testing is a crucial step before releasing a product. With so many approaches to testing, end-to-end testing (E2E testing) may appear as the most time- and resource-consuming method, but it may be the most significant. It ensures software quality and creates confidence in the entire application.
How does this approach differ from the rest? This methodology is essential for checking the software’s usability from the user’s perspective. How would a customer behave, where would they click, and what do they expect?
End-to-end testing aims to ensure that all components work together to perform a particular function. The tester simulates an actual user interacting with the application with various inputs and expected outputs in mind. All the steps during the testing process imitate a real-world scenario and guarantee a satisfactory user experience. As a result, users can browse well-built PWA eCommerce sites, native apps, and SaaS products.
This post will examine end-to-end testing and the steps required to initiate and complete any E2E test.
What is end-to-end testing?
End-to-end testing, or E2E testing, is the process of evaluating a piece of software from beginning to end in the manner in which actual users will use it. For example, the tester may access a website from a desktop or mobile device, add a product to the cart, open the cart, and purchase. The goal is to run the application along with all its dependencies, including the database, third-party services, metrics, logging, etc., regardless of the software type. E2E testing is most often executed after completing functional and system testing.
Suppose you want to test a web application. You open a browser, type in the needed link or request, use the application as intended, and see how it behaves. You can also employ this method to check a desktop application or API, making calls like actual users.
Why do you need to perform end-to-end testing?
Although end-to-end testing might seem comprehensive, you should combine it with several other testing techniques to build a solid continuous integration process. Think about the following test types:
- unit testing, which requires every system component to function as intended;
- functional testing, ensuring that the system responds appropriately to a specific input;
- integration testing, combining and evaluating the various software modules as a whole.
However, having these tests in place doesn’t exclude E2E testing. End-to-end testing, which concentrates on the entire user workflow, differs from the tests discussed above. It is essential for testing overall functionality and numerous systems.
You may employ the unit test at the lowest level, evaluating a small routine written by programmers. These small routines, or features, form the entire application and are necessary for receiving fast feedback.
To test how these components work together, you run integration tests. Integration tests involve using two or more elements in a test environment, with the outcome being validated. However, even if all of these tests pass without a hitch, there may still be errors or unfulfilled criteria. End-to-end testing is useful in this situation.
To begin with, unit and integration tests don’t include the user interface (UI) if you have one. Only an end-to-end test can answer these questions:
- How well-organized is the user interface?
- Does it include all the required components?
- Will the user be able to accomplish their goals?
Modern software has numerous moving parts, making end-to-end testing essential. For example, servers may affect how apps perform, settings must be set up correctly, and external dependencies may affect the application behavior. Separate component testing will only partially address this.
End-to-end testing is popular due to the reasons such as:
- increases test coverage by allowing teams to incorporate more specific test cases compared to the unit and functional testing;
- runs the test cases depending on the end user’s potential actions to make the application operate properly;
- allows release teams to automate crucial user pathways, which helps them decrease time to market;
- lowers the overall cost of developing and maintaining the product by speeding up software testing;
- helps find issues predictably and consistently.
How do end-to-end tests work? An explanation of the testing life cycle
End-to-end testing uses test suites with numerous test cases to track the flow of the software system and its supporting systems and find points where the flow is interrupted, leading to errors. It involves the following four stages:
1. Test planning