Using --no-push and remote caching dont work with each other

[dosilyoun]

Actual behavior
If I build and push with kaniko using remote caching, everything works as expected. If I just want to create a tarball and dont push final image but use remote-cache for the layers then it is not working.

Error uploading layer to cache: failed to push to destination ..io/********:*** POST https://..io/v2/****/blobs/uploads/: : Not Found

Expected behavior
I am able to use remote caching even If I dont push the built image itself

To Reproduce
Use any docker image to build and the most recent kaniko debug docker image.
Use flags --cache, --cache-repo and --no-push.

Description	Yes/No
Please check if this a new feature you are proposing	No
Please check if the build works in docker but not in kaniko	Yes
Please check if this error is seen when you use --cache flag	Yes
Please check if your dockerfile is a multistage dockerfile	No

[JeromeJu]

Thanks for the issue @dosilyoun , would you mind providing more details i.e. which version of kaniko image is used here? There happened to be a patch on --no-push option with the usage of tarball in v1.15.0 earlier, wondering if that could be the corner case there.

[dosilyoun]

@JeromeJu I have only used v1.15.0

[dosilyoun]

@JeromeJu v1.15.0 version of kaniko debug image:
used parameters: --context=/builds/test --dockerfile=/builds/test/Dockerfile --destination=test.jfrog.io/test-repo/test: --cache=true --cache-repo=test.jfrog.io/test-repo --tar-path=test-image.tar --image-name-tag-with-digest-file=digest-file-test-image.tar --no-push --skip-push-permission-check --reproducible --log-timestamp=true --compressed-caching=false --ignore-path=/usr/lib/libcrypto.so.3 --ignore-path=/usr/lib/libssl.so.3

warning message:
WARN[2023-12-18T11:12:51Z] Error uploading layer to cache: failed to push to destination test.jfrog.io/test-repo:9a1bb639d73987c818596cce99235f8de7b5779d47fd193e01507a675df79543: POST https://test.jfrog.io/v2/test-repo/blobs/uploads/: : Not Found

this file has never existed in my JFrog artifactory(https://test.jfrog.io/v2/test-repo/blobs/uploads/)

[aaron-prindle]

As noted in #3180, the fix here was not correct and has been undone given the --no-push-cache flags usage and current use cases around pushing cached images but not the target image. To not push cache layers, the --no-cach-push flag should be used and to not push anything both the --no-push and --no-push-cache flag should be used. This was not documented well prior, this PR adds this flag to the public docs:
https://github.com/GoogleContainerTools/kaniko/pull/3188/files