This is the final part of an optimization that I've been refactoring towards for awhile.
If the Dockerfile consists of no RUN commands, or cached RUN commands, followed by metadata-only
operations, we can skip downloading and unpacking the base image.
gometalinter is broken @ HEAD, and I looked into why that was. During
that process, I remembered that we took the linting scripts from
skaffold, and found that in skaffold gometalinter was replaced with
GolangCI-Lint:
https://github.com/GoogleContainerTools/skaffold/pull/619
The change made linting in skaffold faster, so I figured instead of
fixing gometalinter it made more sense to remove it and replace it with
GolangCI-Lint for kaniko as well.
Extracting the layers of the filesystem in order will make it easier to
extract cached layers and deal with hardlinks.
This PR implements extracting in order and adds an integration tests to
make sure hardlinks are extracted properly.
It also fixes two bugs I found when extracting symlinks:
1. We'd get a "file exists" error when trying to symlink to an existing
file with a whiteout later in the layer tarball
2. We'd get a "file exists" error when trying to create a symlink from a
file that was created in a prior layer (perhaps as a regular file or as
a symlink pointing to someting else)
To fix both of these, we resolve all symlinks in a layer at the end. I
also added logic to delete any existing paths before creating the
symlink.
Issue 291 pointed out that symlink "../proc/self/mounts" in the fedora image wasn't being extracted properly and kaniko was erroring out.
This is because the file path wasn't absolute so kaniko wasn't recognizing it as a whitelisted path.
With this change, we first resolve a path to it's absolute path before checking the whitelist.
* Vendor changes for go-containerregistry switch.
* Manual changes for go-containerregistry switch.
The biggest change is refactoring the tarball unpacking.
* Pull more of container-diff out.
* More vendor removals.
* More unit tests.
dlorenc
peter-evans
priyawadhwa
xanonid
Sharif Elgamal
Matt Rickard