Prebuild hook always run

[nickdapper]

The pre/post build hooks created from #1441 are a great addition. I would like to improve upon this further to always run certain hooks or add another hook.

Example:
I am building Docker images. As far as I know, the build phase parses all the contents of the docker image and generates a hash. We are building Golang apps that run within a docker container. If the Go code has changed, it will not rebuild. We can issue a go build for each command before running skaffold build. This is fine for a small project with only one service or a couple services. This becomes an issue for 20+ services in a monorepo. An optimization we are using is building all binaries at the same time. This speeds up generation of all the binaries using Go's internal cache by loading all the modules. Example here: ko-build/ko#314

Expected behavior

Always run the prebuild hook or define a new hook that always runs. This would run prior to the build phase that checks the hash.

Actual behavior

The prebuild hook only runs if the build needs to run

Information

• Skaffold version: v2.3.0
• Operating system: Mac
• Installed via: brew

[renzodavid9]

Hey @nickdapper, thanks for opening this issue. I have a couple of questions to understand more about the example you mentioned:

1. Do you have a skaffold.yaml config file that you can share to understand how is the setup of your project?
2. From the example, I understand that you are using the hooks to execute an image build, right? And also, I understand that Skaffold itself is not triggering the build process when you do a code change, and that's the reason you are doing it through the hooks, right?
3. Could you also share which Skaffold command are you using?

If the Go code has changed, it will not rebuild.

This is something that I'm curious to understand why is not happening in your case. For example, when you run skaffold dev in a project, Skaffold should be able to detect code changes, and if needed trigger an image build, and deploy.

Thanks!

[renzodavid9]

Hey @nickdapper! Just following up on the questions from previous comment. Please let us know if you have the details. Thanks! 😄