A simple Via CEP Wrapper to demonstrate GoLang tests usage
Demonstrate how struct services could make easy to build and test a Go application.
A simple API that wraps ViaCEP, a REST API to search CEP information.
curl localhost:8080/via_cep_wrapper/03010-000
The code is spplited on two branchs: using_functions and using_service_struct
- The code is built upon functions only
- There is only data structs
- All tests depend on inner layers
- This leads to complex integration tests
- To test the handler layer, the code must mock the Http client of viaCEP
- The code is built upon abstractions (interfaces) and implementations (structs)
- All tests depend on mocks, built with GoMock
- This leads to simple unit tests
- To test the handler layer, the code must only mock the layer below, in that case, the Service layer
Both code do their job but with different approaches.
On my previous experiences, the functions approach worked quite well with small and simple code bases, but adding external dependencies like APIs or Databases, or even growing the code, made the test to complex to maintain and understand.
Nowadays, I prefer the struct service approach, it has proved that for even large code base works quite well