API First approach based on OpenAPI code generation

The following flow describes how to do any change in the API layer.

1)Apply the change to api-spec.yaml
2)Generate the API interface via the command described in 'Generating interface from specification'
3)Copy generated interface code into the files located in src/your-project-name/ControllersInterface
4)Copy generated models code into the files located in src/your-project-name/Models
5)Provide implementation for the defined interfaces in the corresponding files in ControllersImplementation.

openapi-generator generate -i api-spec.yaml -g aspnetcore --additional-properties=packageName=NetCore.ApiFirst.OpenApi.Generator.WebApi,sourceFolder=autogen

The generated code is in the folder autogen, the important bits are the generated classes inside the Controllers folder which must be updated to Abstract classes

During build in CI/CD it is possible to generate the API interface from specification and use tools like bash cmp to compare to the actual api interface

cmp --silent
src/NetCore.ApiFirst.OpenApi.Generator.WebApi/ControllersInterface/PetsApiController
autogen/Controllers/DefaultApi.cs