tagger

README

Tagger

Tagger is a hack to prevent gc from breaking packages

Packages are referenced from repositories via their digest. This means that if a tag on a configuration bundle mutates, the previous artifact may no longer have a tag associated with it. These are considered "dangling" images and will be collected (deleted) when Harbor runs its garbage collection cycle.

The issue with this is, if a package repository references that no longer existent digest, it will fail to retrieve the bundle, breaking the package.

There are two changes that must take place:

1. imgpkg should set a default (additional) tag on bundles it pushes[0]
2. we must scan our package bundles and add an arbitrary and unique tag to ensure that they are never garbage collected.

This commit solves 2. It scans all the projects that represent package bundles in TCE. It then resolves the artifacts for each of those bundles. For each artifact it looks at the tags and sees if it has the expected, unique, tag. The tag we've got with is the first 10 characters of the digest's sha256 value. As an example:

sha256:0c3d0f33c171e437268e57bdbe0d83feb1606362d8235f1b656556da8c944e18

would have a required tag value of c3d0f33c17.

If missing, this tag is added to the artifact. If it exists, no operation is triggered.

Building

TAG=1.0.0 make build

Building and Pushing

TAG=1.0.0 make build-and-push

Running it

1. Run docker login, pointed at projects.registry.vmware.com
2. Run Tagger

docker run \
  -v ${HOME}/.docker/config.json:/root/.docker/config.json \
  projects.registry.vmware.com/tce/tagger:0.1.0