End-to-End Testing Tutorial: Learn in Three Minutes!
What End-to-End testing is, and how to do it yourself!
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Software systems nowadays are complex and interconnected with numerous subsystems. If any of the subsystems fails, the whole software system could crash. This is a major risk and can be avoided by end-to-end testing. By providing truthful answers to the What-Why-When questions, in this article, we will walk you through the general knowledge of end-to-end testing, its benefits and how to measure success.
End-to-End Testing: What is it?
End-to-end (E2E) testing is a technique that tests the entire software product from beginning to end to ensure the application flow behaves as expected. It defines the product’s system dependencies and ensures all integrated pieces work together as expected.
The main purpose of E2E testing is to test from the end user’s experience by simulating the real user scenario and validating the system under test and its components for integration and data integrity.
Why is End-to-End Testing Important?
End-to-end testing has been more reliable and widely adopted because of these following benefits:
- Expand test coverage
- Ensure the correctness of the application
- Reduce time to market
- Reduce cost
- Detect bugs
Modern software systems allow subsystem interactions through advancements in technology. Whether the subsystem is the same or different from the main system, within or outside the organization, subsystem failures can cause adverse effects throughout the entire system.
System risks can be avoided by performing the following:
- Verifying the system flow
- Increasing test coverage areas
- Detecting issues associated with the subsystem
E2E testing broadly appeals to many groups:
- Developers benefit from it because most of the testing is offloaded to others.
- Testers find it useful because writing tests that verify real-world behavior help them avoid problems and achieve a greater sense of accomplishment.
- Managers like it because user simulation tests let them know how a failing test would impact the user.
When to Apply End-to-End Testing
There are many scenarios to apply end-to-end testing. Here’s an example:
Before testing, designers and developers create a list of which UI, functions or features that need to be performed. Data flow should be tracked between systems to find dependencies, flaws, and inaccuracies. Teams also have to prepare the conditions – factors that may change any interface options – before testing.
E2E testing is regularly conducted on finished products and systems, making each review a test of the completed system. A second test will take place if the system does not output what is expected or if a problem is found. In this case, the team will have to record and analyze the data to determine the issue’s origin; then fix and re-test them.
End-to-End Testing Lifecycle
An end-to-end testing lifecycle consists of four components: test planning, test design, test execution, and results analysis.
- Test planning: Specifies key tasks, associated schedule, and resources
- Test design: Test specifications, test case generation, risk analysis, usage analysis, and scheduling tests
- Test execution: Execute test cases and documents testing results
- Results analysis: Analyzes test results, evaluate testing, and perform additional testing if necessary.
End-to-end Testing Methods
Horizontal E2E Testing
A commonly used method occurring horizontally across the context of multiple applications and easily takes place in a single ERP (Enterprise Resource Planning) application. Here’s an example. A Web-based application of an e-commerce system includes accounts, product inventory status, and shipping details.
Vertical E2E Testing
This method refers to testing in layers, meaning that tests happen in sequential, hierarchical order. To ensure quality, each component of a system or product is tested from start to finish. Vertical testing is often used to test critical components of a complex computing system which does not typically involve users or interfaces.
Metrics for End-to-End Testing
Some of the many metrics used for E2E testing are:
- Test Case Preparation Status: Used to determine the specific position of the test cases that are under preparation, compared to planned test cases.
- Test Progress Tracking: Test progress should be tracked on a weekly basis. This step will provide regular details of test completion percentage, such as passed/failed, executed/unexecuted, valid/invalid test cases, and so on.
- Defects Status and Details: It gives a weekly percentage of open and closed defects. Also, weekly defect distributions are based on severity and priority.
- Environment Availability: The actual number of operational hours and hours scheduled per day for testing.
Overall, end-to-end testing is critical for the full and comprehensive assessment of real-world conditions that an application may face. While end-to-end testing is beneficial in so many ways, it can also be very challenging. So make sure that you are aware of the barriers to end-to-end testing, or you may find yourself headed for disaster.
Published at DZone with permission of Oliver Howard. See the original article here.
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