go-containerregistry VS buildkit

I also explored another module, go-containerregistry, in order to build images without root privileges. The approach is completely different, and we can manipulate each component of the container image separately. This can present an advantage, if you're looking for a way to fine tune things.

Use crane ls in a different job to check the tags in the registry. Create an artifact from its output that you evaluate in your kaniko job to check if the build should run or not.

Multi-arch builds are easy to "transfer" IMHO

crane cp docker.io/openfaas/gateway:0.10.0 ghcr.io/openfaas/gateway:0.10.0

If you've not used it yet - do take a look. Crane doesn't pull the images into a local Docker library for re-tagging and re-pushing.

https://github.com/google/go-containerregistry/blob/main/cmd...

crane - tool to copy images from one repo to another - https://github.com/google/go-containerregistry/blob/main/cmd/crane/doc/crane.md

pretty sure the crane being referred by alex is this one: https://github.com/google/go-containerregistry/tree/main/cmd/crane

https://github.com/google/go-containerregistry/tree/main/cmd...

It was recommended in this article:

This is one of my absolute favorite topics. Pardon me while I rant and self-promote :D

Dockerfiles are great for flexibility, and have been a critical contributor to the adoption of Docker containers. It's very easy to take a base image, add a thing to it, and publish your version.

Unfortunately Dockerfiles are also full of gotchas and opaque cargo-culted best practices to avoid them. Being an open-ended execution environment, it's basically impossible to tell even during the build what's being added to the image, which has downstream implications for anybody trying to get an SBOM from the image for example.

Instead, I contribute to a number of tools to build and manage images without Dockerfiles. Each of them are less featureful than Dockerfiles, but being more constrained in what they can do, you can get a lot more visibility into what they're doing, since they're not able to do "whatever the user wants".

1. https://github.com/google/go-containerregistry is a Go module to interact with images in the registry and in tarballs and layouts, in the local docker daemon. You can append layers, squash layers, modify metadata, etc.

2. crane is a CLI that uses the above (in the same repo) to make many of the same modifications from the commandline. `crane append` for instance adds a layer containing some contents to an image, entirely in the registry, without even pulling the base image.

3. ko (https://ko.build) is a tool to build Go applications into images without Dockerfiles or Docker at all. It runs `go build`, appends that binary on top of a base image, and pushes it directly to the registry. It generates an SBOM declaring what Go modules went into the app it put into the image, since that's all it can do.

4. apko (https://apko.dev) is a tool to assemble an image from pre-built apks, without Docker. It's capable of producing "distroless" images easily with config in YAML. It generates an SBOM declaring exactly what apks it put in the image, since that's all it can do.

Bazel's rules_docker is another contender in the space, and GCP's distroless images use it to place Debian .debs into an image. Apko is its spiritual successor, and uses YAML instead of Bazel's own config language, which makes it a lot easier to adopt and use (IMO), with all of the same benefits.

I'm excited to see more folks realizing that Dockerfiles aren't always necessary, and can sometimes make your life harder. I'm extra excited to see more tools and tutorials digging into the details of how container images work, and preaching the gospel that they can be built and modified using existing tooling and relatively simple libraries. Excellent article!

Look at using tools like skopeo or crane

Pretty much any tool works: docker, podman, kaniko, crane(if you're brave), ko... list goes on.

> We are uding docker-in-docker at the moment

You can also run a "less privileged" container with all the features of Docker by using rootless buildkit in Kubernetes. Here are some examples:

https://github.com/moby/buildkit/tree/master/examples/kubern...

https://github.com/moby/buildkit/blob/master/examples/kubern...

It's also possible to run dedicated buildkitd workers and connect to them remotely.

- BuildOp evaluates its input as additional LLB operations to add to the graph to allow for dynamic build graphs (also unused in the Dockerfile frontend)

With the Dockerfile Explorer, we run the Dockerfile frontend[1] that BuildKit uses inside of WASM to parse and produce the LLB output locally in your browser. We then embed the Monaco Editor so that you can change your Dockerfile to see how it impacts the LLB output that BuildKit will use to build your Docker image.

You can see a quick video and read more details on how it all works here: https://depot.dev/blog/dockerfile-explorer.

We'd love any feedback or ideas folks would like around this type of tool!

[0] https://github.com/moby/buildkit#exploring-llb

Now since Kubernetes works off of containerd I'll be taking a different approach on handling container builds by using nerdctl and the buildkit that comes bundled with it. I'll do this on the amd64 control plane node since it's beefier than my Raspberry Pi workers for handling builds and build related services. Go ahead and download and unpack the latest nerdctl release as of writing (make sure to check the release page in case there's a new one):

There's a 2-year-old moby/buildkit GitHub issue about frequent build cache misses when using the BuildKit docker-container driver and multi-stage builds. Anyone else in this sub run into this problem and/or have reasonable workarounds? It seems like something that should come up pretty often.

A couple months ago I encountered a bug in buildkit - when enabling OpenTelemetry tracing, we got occasional panics. With a bit of investigation, we found the cause, fixed and tested in our fork and internal deployments, and pushed to upstream.

I do some search in the internet and there seems to be no good solution, so I just create a feature request: https://github.com/moby/buildkit/issues/3859

Yeah, only Linux containers at the moment, BuildKit is the way we are constructing pipelines and doing caching. Split on if we will support non-linux hosts, but definitely want to find a good solution to not doing Docker-in-Docker.

Relevant issues are https://github.com/moby/buildkit/issues/3011 and https://github.com/moby/buildkit/issues/1512.