Proposal: Control over skaffold tasks/goals

Relevant issue: https://github.com/GoogleContainerTools/skaffold/issues/3457

Motivation

Jib makes assumptions about what files to watch based on what it knows. Users may have other ideas about intermediate build processes that occur before jib is ready to process anything. Allowing users to configure the skaffold tasks to correctly reflect what their build is doing could help our users use skaffold more effectively.

Current Configuration

None: Jib does not have any way to configure _skaffold tasks

Proposed Configuration

The proposal is to allow users to configure what jib shares with skaffold

1. Allowing inclusion/exclusion on top of the jib defaults for files to watch
2. Allow exclusion of files that will be sync'd

The final jib output will not deviate from what skaffold expects, but just allows for tighter control of what is sent to skaffold from jib.

Gradle (build.gradle)

jib {
  ...
  skaffold {
    watch {
      buildIncludes = 'script.gradle'
      includes = project.files('my/custom/inputs')
      excludes = ['some/file/i/dont/want/watched']
    }
    sync {
      exclude = 'a/file'
    }
  }
}

Maven (pom.xml)

<configuration>
  <skaffold>
    <watch>
      <buildIncludes>
        <buildInclude>some/pomfile.xml</buildInclude>
      </buildIncludes>
      <includes>
        <include>some/file</include>
        <include>another/file</include>
      </includes>
      <excludes>
        <exclude>not/me</exclude>
        <exclude>/absolute/path/to/not/me</exclude>
      <excludes>
    </watch>
    <sync>
      <excludes>
        <exclude>some/file</exclude>
      <excludes>
    </sync>
  </skaffold>
</configuration>

Changes to Skaffold

None