Bazel warns the genrule //example:base which outputs a directory

[tetsuok]

When I build //example:base and other targets that depend on it, Bazel warns the output of //example:base is a directory as follows:

$ bazel build //example:base
...
WARNING: /Volumes/work/github/rules_oci/example/BUILD.bazel:25:8: output 'example/layout' of //example:base is a directory; dependency checking of directories is unsound

Build itself succeeds, but it would be nice to fix the warning or work around the underlying issue.

I see the similar warning when I ran bazel build //src:image in e2e/js_image_oci of rules_js (Probably, the root cause of the warning is same):

WARNING: /private/var/tmp/_bazel_t/ce0e746d0a64bfce50fc270eb1254184/external/debian_amd64/BUILD.bazel:2:8: output 'external/debian_amd64/layout' of @debian_amd64//:image is a directory; dependency checking of directories is unsound

[alexeagle]

I don't think we can do anything about this. We use genrule in that example. https://docs.aspect.build/rules/aspect_bazel_lib/docs/run_binary/ knows how to produce directory outputs, but doesn't permit a bash one-liner like we use in that example.

I think the upside is that users would generally never use a genrule. Maybe we could even remove that from our examples, or make an examples/genrule folder that is documented as "produces a warning from Bazel, don't do it this way unless you have reason X or Y"

[alexeagle]

@thesayyn I think we should just change //examples:base to use our normal oci_pull mechanism now, this was using crane pull in a genrule for historical reasons.

[thesayyn]

@thesayyn I think we should just change //examples:base to use our normal oci_pull mechanism now, this was using crane pull in a genrule for historical reasons.

done in #165 but i needed to fix #151 so working on it.