Try using ko to build images

Signed-off-by: Xe Iaso <me@xeiaso.net>

cmd/containerbuild/.gitignore

@@ -0,0 +1 @@
+images

cmd/containerbuild/main.go

@@ -0,0 +1,133 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"log"
+	"log/slog"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+
+	"github.com/TecharoHQ/anubis/internal"
+	"github.com/facebookgo/flagenv"
+)
+
+var (
+	dockerAnnotations = flag.String("docker-annotations", os.Getenv("DOCKER_METADATA_OUTPUT_ANNOTATIONS"), "Docker image annotations")
+	dockerLabels      = flag.String("docker-labels", os.Getenv("DOCKER_METADATA_OUTPUT_LABELS"), "Docker image labels")
+	dockerRepo        = flag.String("docker-repo", "registry.int.xeserv.us/techaro/anubis", "Docker image repository for Anubis")
+	dockerTags        = flag.String("docker-tags", os.Getenv("DOCKER_METADATA_OUTPUT_TAGS"), "newline separated docker tags including the registry name")
+	slogLevel         = flag.String("slog-level", "INFO", "logging level (see https://pkg.go.dev/log/slog#hdr-Levels)")
+)
+
+func main() {
+	flagenv.Parse()
+	flag.Parse()
+
+	internal.InitSlog(*slogLevel)
+
+	koDockerRepo := strings.TrimRight(*dockerRepo, "/"+filepath.Base(*dockerRepo))
+	version, err := run("git describe --tags --always --dirty")
+
+	slog.Debug(
+		"ko env",
+		"KO_DOCKER_REPO", koDockerRepo,
+		"VERSION", version,
+	)
+
+	os.Setenv("KO_DOCKER_REPO", koDockerRepo)
+	os.Setenv("VERSION", version)
+
+	setOutput("version", version)
+
+	if *dockerTags == "" {
+		log.Fatal("Must set --docker-tags or DOCKER_METADATA_OUTPUT_TAGS")
+	}
+
+	images, err := parseImageList(*dockerTags)
+	if err != nil {
+		log.Fatalf("can't parse images: %v", err)
+	}
+
+	for _, img := range images {
+		if img.repository != *dockerRepo {
+			slog.Error(
+				"Something weird is going on. Wanted docker repo differs from contents of --docker-tags. Did a flag get set incorrectly?",
+				"wanted", *dockerRepo,
+				"got", img.repository,
+				"docker-tags", *dockerTags,
+			)
+			os.Exit(2)
+		}
+	}
+
+	var tags []string
+	for _, img := range images {
+		tags = append(tags, img.tag)
+	}
+
+	output, err := run(fmt.Sprintf("ko build --platform=all --base-import-paths --tags=%q --image-user=1000 --image-annotation=%q --image-label=%q ./cmd/anubis | tail -n1", strings.Join(tags, ","), *dockerAnnotations, *dockerLabels))
+	if err != nil {
+		log.Fatalf("can't run ko build, check stderr: %v", err)
+	}
+
+	sp := strings.SplitN(output, "@", 2)
+
+	setOutput("digest", sp[1])
+}
+
+type image struct {
+	repository string
+	tag        string
+}
+
+func newlineSep2Comma(inp string) string {
+	lines := strings.Split(inp, "\n")
+	return strings.Join(lines, ",")
+}
+
+func parseImageList(imageList string) ([]image, error) {
+	images := strings.Split(imageList, "\n")
+	var result []image
+	for _, img := range images {
+		if img == "" {
+			continue
+		}
+
+		// reg.xeiaso.net/techaro/anubis:latest
+		// repository: reg.xeiaso.net/techaro/anubis
+		// tag:        latest
+		parts := strings.SplitN(img, ":", 2)
+		result = append(result, image{
+			repository: parts[0],
+			tag:        parts[1],
+		})
+	}
+
+	if len(result) == 0 {
+		return nil, fmt.Errorf("no images provided, bad flags??")
+	}
+
+	return result, nil
+}
+
+// run executes a command and returns the trimmed output.
+func run(command string) (string, error) {
+	bin, err := exec.LookPath("sh")
+	if err != nil {
+		return "", err
+	}
+	cmd := exec.Command(bin, "-c", command)
+	cmd.Stderr = os.Stderr
+	out, err := cmd.Output()
+	if err != nil {
+		return "", err
+	}
+	return strings.TrimSpace(string(out)), nil
+}
+
+func setOutput(key, val string) {
+	fmt.Printf("::set-output name=%s::%s\n", key, val)
+}