Set GitHub release as 'latest' if target release is newest

Signed-off-by: Marvin Beckers <mail@embik.me>

go.mod

@@ -39,6 +39,7 @@ require (
 	google.golang.org/api v0.152.0
 	gopkg.in/yaml.v2 v2.4.0
 	k8s.io/apimachinery v0.29.3
+	k8s.io/utils v0.0.0-20240102154912-e7106e64919e
 	sigs.k8s.io/bom v0.6.0
 	sigs.k8s.io/mdtoc v1.3.0
 	sigs.k8s.io/promo-tools/v3 v3.6.0
@@ -294,7 +295,6 @@ require (
 	k8s.io/client-go v0.28.4 // indirect
 	k8s.io/klog/v2 v2.110.1 // indirect
 	k8s.io/kube-openapi v0.0.0-20231010175941-2dd684a91f00 // indirect
-	k8s.io/utils v0.0.0-20240102154912-e7106e64919e // indirect
 	modernc.org/libc v1.37.6 // indirect
 	modernc.org/mathutil v1.6.0 // indirect
 	modernc.org/memory v1.7.2 // indirect

pkg/announce/github_page.go

@@ -28,6 +28,7 @@ import (
 
 	"github.com/sirupsen/logrus"
 
+	"k8s.io/utils/ptr"
 	"sigs.k8s.io/bom/pkg/serialize"
 	"sigs.k8s.io/bom/pkg/spdx"
 	"sigs.k8s.io/release-sdk/git"
@@ -291,19 +292,37 @@ func UpdateGitHubPage(opts *GitHubPageOptions) (err error) {
 		return errors.New("tag not found while trying to publish release page")
 	}
 
-	// Get the release we are looking for
-	releases, err := gh.Releases(opts.Owner, opts.Repo, true)
+	// Get the release we are looking for. We only need to fetch prereleases
+	// if the release is a prerelease.
+	releases, err := gh.Releases(opts.Owner, opts.Repo, isPrerelease)
 	if err != nil {
 		return fmt.Errorf("listing the repositories releases: %w", err)
 	}
 
-	// Does the release exist yet?
+	// Does the release exist yet and should it be marked as latest?
 	var releaseID int64
 	commitish := ""
+	// No pre-release should ever be marked as "latest"
+	markAsLatest := !isPrerelease
+
 	for _, release := range releases {
 		if release.GetTagName() == opts.Tag {
 			releaseID = release.GetID()
 			commitish = release.GetTargetCommitish()
+		} else if markAsLatest {
+			// If this release is not identical to the one being cut right now,
+			// we will check if *our* release is lower than the release from the loop.
+			// If the first page of releases does not include a release that is
+			// greater than *our* release, we can assume that ours will be the
+			// latest release right now.
+			releaseSemver, err := util.TagStringToSemver(release.GetTagName())
+			if err != nil {
+				return fmt.Errorf("parsing existing release tags as semver: %w", err)
+			}
+
+			if semver.LE(releaseSemver) {
+				markAsLatest = false
+			}
 		}
 	}
 
@@ -319,11 +338,22 @@ func UpdateGitHubPage(opts *GitHubPageOptions) (err error) {
 	// Post release data
 	logrus.Infof("%s the %s release on github...", releaseVerb, opts.Tag)
 
+	ghOpts := &github.UpdateReleasePageOptions{
+		Name:       &opts.Name,
+		Body:       ptr.To(output.String()),
+		Draft:      &opts.Draft,
+		Prerelease: &isPrerelease,
+	}
+
+	if markAsLatest {
+		ghOpts.Latest = ptr.To(true)
+	}
+
 	// Call GitHub to set the release page
-	release, err := gh.UpdateReleasePage(
+	release, err := gh.UpdateReleasePageWithOptions(
 		opts.Owner, opts.Repo, releaseID,
-		opts.Tag, commitish, opts.Name, output.String(),
-		opts.Draft, isPrerelease,
+		opts.Tag, commitish,
+		ghOpts,
 	)
 	if err != nil {
 		return fmt.Errorf("updating the release on GitHub: %w", err)