Scala software developer and system engineer for satellite mission planning. Likes Rust and Arch.
How not to serialize binary data:
import io.circe._
import com.google.protobuf.ByteString
final case class Message(body: ByteString)
object Message {
implicit val encodeMessage: Encoder[Message] =
Encoder.instance { message =>
val array = message.body.toByteArray
.map(_.toInt)
.map(Json.fromInt)
Json.fromValues(array)
}
}
Sadly, I actually saw this today… I didn’t do a git blame; I guess I’d never be able to look at that person again 😢
TIL that you can declare a (case) class in a method body. In other words the following is valid Scala code:
def foo(s: String): Unit = {
final case class Foo(i: Int)
}
Even after six years Scala continues to surprise.
A node hosts a Gitlab runner and a small k3s cluster which runs a few services as regular kubernetes deployments. A CI job pinned to that runner builds Docker images for these services services, updates the image of the corresponding deployments, and starts a few system and acceptance tests. The CI job does not push those images to the in-house registry; to avoid polluting the registry with hundreds of images it just builds locally.
Each test then scales each deployment to zero replicas to effectively stop all services, clears the system’s underlying database, and scales the service deployments back to a small number of replicas sufficient for testing.
The whole thing runs fine until one day the replicas randomly fail to start.
Some electron-based flatpaks (e.g. Mattermost, see https://github.com/flathub/com.mattermost.Desktop/issues/23) for some reason ignore Gnome’s HTTP proxy settings. In this case we can set the proxy directly inside the affected flatpak.
LWN recently covered a comprehensive guide about discoverable GPT disk images by Lennart Poettering.
I started playing around with secure boot, with the ultimately goal of setting it up on my laptop. I experimented in a libvirt/qemu VM and to my surprise a custom secure boot is rather easy (the Secure Boot page on the Arch Wiki suggests quite the contrary), thanks to dracut and a fairly recent tool named sbctl which just recently had it’s first release.
Installing Arch on a LUKS-encrypted dsik traditionally required a few careful configuration steps to configure the proper root device for booting; if any of these steps was omitted or done wrongly the system would fail to boot. With systemd and dracut however a LUKS-encrypted Arch system can boot safely and reliably without any configuration:
The following commands demonstrate a fresh Arch installation from the Arch installation media into a libvirt VM. Installing to a pristine physical machine or a different virtual machine provider should require only minimal changes; adapting an existing system may be more difficult and require more work.
Observations from using systemd-homed for a couple of days:
I like Arch Linux and use it for my systems whereever possible. In this post I’ll briefly go through my preferred Arch Linux setup.