Move logic out of cmd/builder

jabrown85 commented 3 years ago

Description

We would like to push as much validation and processing out of the cmd/builder.go as possible. The cmds are hard to test and keep growing because there is already validation logic present.

Proposed solution

Instead of validating inside of cmd/builder.go, we should put as much validation as possible into builder.go. This probably means introducing and using interfaces that wrap file, and env access. We should write unit tests to cover and possibly remove validation specific acceptance tests. cmd/builder.go is probably the smallest compared to other phases but still has a bit of validation up front and error handling.

Additional context

We need to keep creator as well as library authors in mind here a bit. Having group, plan, err := restorer.Restore(cacheStore) makes sense for platforms building on top of lifecycle, like buildkit. So we may wish to introduce new methods that write the files that can optionally be executed by those platforms and always executed by cmd/builder.go. The validation that occurs in cmd/builder.go maybe shouldn't be executed by creator, for instance.

natalieparellano commented 2 years ago

See #805 (analyzer) and #860 (detector) for how this is done for other phases.

pbusko commented 4 weeks ago

is there anything specific you would like to move out from the cmd/lifecycle/builder.go? It already looks rather minimal tbh

natalieparellano commented 3 weeks ago

The restorer and the exporter are the real culprits here. It's likely we could add some units around builder instantiation.

buildpacks / lifecycle