Shadow Testing a Beginners Guide

Delivery of new features to users without disrupting their experience is of utmost importance. Shadow releases and then comes into the scene here. The term 'Shadow release' sounds quite complex to a novice in the testing of software. However, it is a really effective technique by which teams ensure the smooth rollout of new features. This blog post will explain what Shadow releases are, why they're used, and how testers can maintain quality during Shadow deployments.

What Is a Shadow Testing?

A Shadow Release (also known as a "Dark Launching") refers to the process of releasing new features to a production environment without making them available to all users immediately. Think of it as a feature that is deployed but not yet visible or usable by the public. Only certain users or systems can access it.

This technique allows development teams to test new features in a real-world production environment, catching any performance or integration issues without impacting the broader user base. Essentially, the code is "live," but hidden from most users.

Why Use Shadow Releases?

Shadow releases are beneficial for several reasons:

1. Risk Reduction: Since only a small portion of users or systems are exposed to the new feature, the risk of disrupting the entire system is minimized.
2. Real-Time Testing: Shadow releases allow for testing in the production environment, which gives you real-world insights into how the feature performs under actual conditions.
3. Feedback Gathering: You can gather feedback from a small subset of users before launching the feature to a wider audience.
4. Gradual Rollout: Shadow releases provide the opportunity for a gradual feature rollout. If the feature works as expected, it can be made available to more users.

How Are Shadow Releases Deployed?

The Shadow release is typically deployed with feature flags or toggles. It is just a switch in the code which enables teams to enable the feature for either some or all of its users without the necessity to deploy any new code. Feature flags ensure that the actual code is in the production environment; however, it is for the most part turned "off" for the majority of the users. Setting up an appropriate test environment is crucial for effective shadow testing.

For example, when you are developing a search function, a new feature of the search function would only be enabled for a small group of internal testers or only to a selective user. The other users continue to use the old version of the search function without even knowing it exists.

The Role of Testing in Shadow Releases

As a software tester, ensuring the quality of a Shadow release involves specific strategies that differ from traditional testing. Here’s how you can ensure the new feature works properly during a shadow deployment:

1. Monitor System Performance

Since the feature is live in production (even though it’s hidden), you need to closely monitor system performance. Look for signs that the new feature is causing issues like slow loading times, server crashes, or increased error rates. Performance testing tools can help you track how the system is handling the new code.

2. Test in Real-Time

The major advantage of Shadow releases is the ability to test in a real-world environment. Conduct real-time testing to ensure the feature interacts well with existing code and doesn’t cause unexpected side effects. Since only a subset of users has access to the feature, it allows you to catch bugs early on.

3. Use A/B Testing

A/B testing is a great way to compare the performance of the old feature with the new one. For example, you can track how users interact with the new feature (e.g., clicks, time spent, errors encountered) and compare those results with users who still have the old feature.

4. User Feedback

Gathering user feedback from the small group who have access to the Shadow release is vital. They can report on the usability of the feature, potential bugs, or performance issues. Based on this feedback, you can refine the feature before it’s fully launched.

5. Prepare for Rollback

Despite thorough testing, things can still go wrong. Always have a rollback plan ready in case the feature introduces critical issues. Rolling back means disabling the feature or reverting to the previous version of the code, ensuring minimal disruption to users.

Best Practices for Testing Shadow Releases

• Test Early and Test Often: Even before the Shadow release, ensure the feature has gone through thorough unit tests, integration tests, and regression tests.
• Focus on Edge Cases: Since Shadow releases are meant to catch issues that might not be obvious during testing in non-production environments, focus on testing edge cases and unusual scenarios that could lead to bugs.
• Automate Where Possible: Automated tests that run as part of your CI/CD pipeline (Continuous Integration/Continuous Deployment) ensure that issues are caught early. Utilizing effective automation testing tools can significantly enhance your shadow testing process.
• Log and Monitor: Set up detailed logging and monitoring for the Shadow release. This will allow you to track how the feature is performing and catch any issues early.

When Should You Use Shadow Releases?

Shadow releases are particularly useful when:

• You want to test a feature in production without making it publicly available.
• The feature is complex and may cause unforeseen issues if released to the entire user base.
• You’re rolling out a new feature gradually to avoid overwhelming your infrastructure.
• Gathering early feedback from a limited set of users or stakeholders is essential.

Suggested Reads- 10 Types of Automation Testing You Need To Know

Conclusion

Shadow releases allow the new features to be tested in live, but their risk to a wider user base is minimized. This means that those hidden features perform well, do not introduce bugs and may be rolled out much more widely to testers. If you focus on real-time testing, performance monitoring, and feedback loops, you can ensure that it works as expected once it is fully rolled out.

Testing a Shadow release seems intimidating when the time comes but, given the right strategies and tools, it indeed becomes a valuable approach to delivering high-quality software at less risk. Being either a novice or an experienced tester, mastering the art of Shadow releases is very much required today in fast-paced development environments.

Need expert help?

F22 Labs specializes in advanced QA testing services, including shadow testing implementation. Our experienced team can help you set up effective shadow releases, automate testing processes, and ensure smooth feature rollouts. We offer tailored solutions for businesses of all sizes, helping you deliver high-quality software with minimized risk. Contact us to enhance your testing strategy.

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