Testing Go (Golang) Applications: From Unit Tests to E2E

The book "Testing Go (Golang) Applications" is a practical guide that will take you step by step from writing your first unit tests to building a comprehensive testing strategy for production projects. The author, an experienced Go developer, shares proven approaches and best practices that will help you create reliable and maintainable software.

What is this book about?

The book covers all key aspects of testing Go applications:

• Testing Basics: test structure, t *testing.T function, table-driven tests, subtests, and parallel execution.
• Unit Testing: testing individual functions, methods, and packages. Using mocks (gomock, testify) and stubs to isolate dependencies.
• Integration Testing: testing interactions with databases, external APIs, and the file system. Working with testcontainers.
• Benchmarks and Profiling: writing and analyzing benchmarks, finding bottlenecks with pprof.
• End-to-End (E2E) Testing: testing HTTP servers, gRPC services, and CLI applications.
• TDD (Test-Driven Development): test-driven development practice with real-world examples.
• CI/CD and Automation: integrating tests into pipelines, parallel execution, working with code coverage.

Who is this book for?

• Junior Go developers who want to learn testing from scratch.
• Middle developers looking to systematize their knowledge and learn advanced techniques.
• Team Leads and Architects who are implementing a testing culture in their teams.
• Developers transitioning to Go from other languages seeking Go-specific testing practices.

What will you learn?

• How to write readable, reliable, and maintainable tests.
• How to effectively use the built-in testing package and popular libraries (testify, gomock, httptest).
• How to test HTTP handlers, databases, gRPC services, and asynchronous code.
• How to measure performance and find problems using benchmarks.
• How to build a development process where tests are not a burden but a tool for acceleration.
• How to integrate tests into GitHub Actions, GitLab CI, and other systems.

The book contains many real-world code examples that you can immediately apply to your projects. Each chapter ends with practical exercises to reinforce the material. You will learn not just to write tests, but to think in the testing paradigm, which will make your code cleaner, safer, and more professional.

After reading this book, you will be able to confidently design architecture that is easy to test, and you will be ready to work in teams where code quality is a priority.