22 May 2023
07 Min. Read
Testing Pyramid: Why won’t it work for microservices testing?
Fast Facts
Get a quick overview of this blog
Understand the challenges of testing microservices due to their distributed and independent nature.
Discover a tailored approach for testing microservices, including the modified testing pyramid and the focus on contract [+data] testing.
Learn about tools like HyperTest that facilitate effective testing of microservices, especially through contract testing.
Uncover the benefits of adopting the HyperTest way of testing microservices, such as easy maintenance, quicker issue identification, and seamless CI/CD integration.
Microservices architecture has been gaining popularity due to its ability to enhance the agility, scalability, and resiliency of applications. However, testing microservices can be challenging because of their distributed and independent nature. In traditional monolithic applications, the testing pyramid is a widely used framework for testing applications. This framework emphasizes the importance of unit testing, integration testing, and end-to-end testing in ensuring software quality.
However, this testing pyramid may not work effectively for testing microservices architecture. In this blog post, we will explore the reasons why the traditional testing pyramid may not work for testing microservices and provide the modified testing pyramid as the ultimate solution.
The Traditional Testing Pyramid
The traditional testing pyramid is a framework that emphasizes the importance of unit tests, integration tests, and end-to-end tests in ensuring software quality. The pyramid is shaped like a triangle, with unit tests at the bottom, followed by integration tests in the middle, and end-to-end tests at the top.
Unit tests are used to test the smallest units of code, typically at the function or class level.
Integration tests are used to test how different modules of the application interact with each other.
End-to-end tests are used to test the entire application from a user perspective.
The traditional "Test Pyramid" suggests balancing unit, integration, and end-to-end tests. This pyramid is designed to provide a framework for testing software applications. However, with the rise of microservices, the traditional testing pyramid has become less useful.
Where the Traditional Testing Pyramid Lacks?
Microservices architecture is more complex than monolithic architecture. In a microservices architecture, services are distributed and independent, and each service may have its own database, making testing more challenging.
This test pyramid approach needs to be modified for testing microservices. E2E tests need to be completely dropped. Aside from being time-consuming to build and maintain, E2E tests execute complete user-flows on the entire application with each test. This requires all services under the hood to be simultaneously brought up (including upstream), even when it is possible to catch the same kind and the same number of failures by testing only a selected group of services; only the ones that have undergone a change.
1. Microservices are highly distributed: Microservices architecture is based on breaking down an application into smaller, independently deployable services that communicate with each other over a network. This distributed nature makes it difficult to test the system as a whole using end-to-end tests.
2. Service boundaries are constantly evolving: Microservices architecture allows for rapid iteration and deployment, which means that the boundaries between services can be constantly changing. This serves as a challenge in maintaining end-to-end tests and integration tests as the system evolves.
3. Testing one service in isolation may not provide enough coverage: Because microservices are highly distributed and rely heavily on communication between services, testing one service in isolation may not be sufficient to ensure the overall quality of the system.
4. Independent Releases: In a microservices architecture, services are independently deployable and release cycles are faster. This makes it challenging to test each service thoroughly before release, and end-to-end testing is more critical than in traditional monolithic applications.
The Modified Testing Pyramid for Microservices
Microservices have a consumer-provider relationship between them. In a consumer-provider, one microservice (the consumer) relies on another microservice (the provider) to perform a specific task or provide a specific piece of data. The consumer and provider communicate with each other over a network, typically using a well-defined API to exchange information. This means the consumer service could break irreversibly if the downstream service (provider) changes its response that the consumer is dependent on.
Since APIs are the key to run microservices-based system, testing them via the contracts they exchange while communicating would be an effective strategy to test them. This approach of selecting and testing only one service at a time is faster, cheaper, and more effective, and can be easily achieved by testing contracts [+data] for each service independently.
Test every service independently for contracts [+data], by checking the API response of the service.
Service level isolation is the most effective, manageable and scalable strategy for testing a multi-repo system.
How HyperTest can help you achieve Contract[+data] testing?
HyperTest is a no-code test automation tool for API testing. It is tailor-made to cater the challenges that microservices come with.
It helps in running integration tests for all services deployed with HyperTest. If teams find it difficult to build tests that generate response from a service with pre-defined inputs, there is a simple way to test services one at a time using HyperTest Record and Replay mode.
HyperTest sits on top of each service and monitors all the incoming traffic for the service under test [SUT].
HyperTest will capture all the incoming requests coming to a particular service and all of its upstream, creating a record for each request. This happens 24x7 and helps HyperTest builds context of the possible API requests or inputs that can be made to the service under test.
This recorded traffic is curated into contracts tests by HyperTest. These contracts tests perfectly mimic any actual interaction between the consumer service and the provider service.
These contract tests that capture incoming traffic, are then run on the SUT to generate response from 2 branches which are then compared and validated for contracts [+data].
Benefits of Testing Microservices The HyperTest Way
Service level contract tests are easy to build and maintain. HyperTest builds or generates these tests in a completely autonomous way.
The provider can make changes to their APIs without breaking upstream services.
Reduces the need for developers to talk to each other and coordinate, saving time and unnecessary communication.
HyperTest localizes the root cause of the breaking change to the right service very quickly, saving debugging time.
Very easy to execute, since contract[+data] tests can be triggered from the CI/CD pipelines.
Conclusion
The traditional testing pyramid is no longer suitable for testing microservices. Microservices architecture requires new testing strategies that can address the challenges that come with this architecture. The contract[+data] is the best alternative testing strategy that can be used to test microservices effectively.
This testing strategy focus on testing the API and the interactions between services rather than testing the application as a whole. Adopting this testing strategy will help organizations achieve the scalability, flexibility, and agility that come with microservices architecture.
Schedule a demo today to let HyperTest help you in achieving your contract[+data] testing.
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