feat: provide git metadata env vars to buildpacks

pkg/apis/build/v1alpha2/build_pod.go

@@ -191,6 +191,14 @@ func (b *Build) BuildPod(images BuildPodImages, buildContext BuildContext) (*cor
 	dnsProbeHost := ref.Context().RegistryStr()
 
 	buildEnv := b.Spec.Source.Source().BuildEnvVars()
+	var gitMetadataEnv []corev1.EnvVar
+	if b.Spec.Source.Git != nil {
+		gitMetadataEnv = []corev1.EnvVar{
+			{Name: PlatformEnvVarPrefix + "BPE_GIT_REVISION", Value: b.Spec.Source.Git.Revision},
+			{Name: PlatformEnvVarPrefix + "BP_OCI_REVISION", Value: b.Spec.Source.Git.Revision},
+		}
+	}
+	buildEnv = append(buildEnv, gitMetadataEnv...)
 	for _, envVar := range b.Spec.Env {
 		envVar.Name = PlatformEnvVarPrefix + envVar.Name
 		buildEnv = append(buildEnv, envVar)

pkg/apis/build/v1alpha2/image_builds.go

@@ -2,6 +2,7 @@ package v1alpha2
 
 import (
 	"fmt"
+	"slices"
 	"strconv"
 	"time"
 
@@ -37,6 +38,14 @@ type BuildReason string
 
 func (im *Image) Build(sourceResolver *SourceResolver, builder BuilderResource, latestBuild *Build, reasons, changes string, nextBuildNumber int64, priorityClass string) *Build {
 	buildNumber := strconv.Itoa(int(nextBuildNumber))
+	tags := im.generateTags(buildNumber)
+
+	if resolvedGit := im.resolvedGitSource(sourceResolver); resolvedGit != nil {
+		if shaTag, err := im.gitRevisionTag(resolvedGit.Revision); err == nil && shaTag != "" {
+			tags = appendIfMissing(tags, shaTag)
+		}
+	}
+
 	return &Build{
 		ObjectMeta: metav1.ObjectMeta{
 			Namespace: im.Namespace,
@@ -57,7 +66,7 @@ func (im *Image) Build(sourceResolver *SourceResolver, builder BuilderResource,
 			}),
 		},
 		Spec: BuildSpec{
-			Tags:    im.generateTags(buildNumber),
+			Tags:    tags,
 			Builder: builder.BuildBuilderSpec(),
 			RunImage: BuildSpecImage{
 				Image: builder.RunImage(),
@@ -277,6 +286,39 @@ func (im *Image) generateTags(buildNumber string) []string {
 	)
 }
 
+func (im *Image) resolvedGitSource(sourceResolver *SourceResolver) *corev1alpha1.ResolvedGitSource {
+	if sourceResolver == nil {
+		return nil
+	}
+
+	gitSource := sourceResolver.Status.Source.Git
+	if gitSource == nil {
+		return nil
+	}
+
+	return gitSource
+}
+
+func (im *Image) gitRevisionTag(revision string) (string, error) {
+	if revision == "" {
+		return "", nil
+	}
+
+	tag, err := name.NewTag(im.Spec.Tag, name.WeakValidation)
+	if err != nil {
+		return "", err
+	}
+
+	return fmt.Sprintf("%s:%s", tag.Context().Name(), revision), nil
+}
+
+func appendIfMissing(tags []string, candidate string) []string {
+	if slices.Contains(tags, candidate) {
+		return tags
+	}
+	return append(tags, candidate)
+}
+
 func (im *Image) generateBuildName(buildNumber string) string {
 	return kmeta.ChildName(im.Name, "-build-"+buildNumber)
 }

pkg/apis/build/v1alpha2/image_builds_test.go

@@ -18,6 +18,8 @@ func TestImageBuilds(t *testing.T) {
 }
 
 func testImageBuilds(t *testing.T, when spec.G, it spec.S) {
+	const gitRevision = "9f86d081884c7d659a2feaa0c55ad015a3bf4f1b"
+
 	image := &Image{
 		ObjectMeta: metav1.ObjectMeta{
 			Name: "image-name",
@@ -99,15 +101,15 @@ func testImageBuilds(t *testing.T, when spec.G, it spec.S) {
 		sourceResolver.Status.Source = corev1alpha1.ResolvedSourceConfig{
 			Git: &corev1alpha1.ResolvedGitSource{
 				URL:      "https://some.git/url",
-				Revision: "revision",
+				Revision: gitRevision,
 				Type:     corev1alpha1.Commit,
 			},
 		}
 
 		latestBuild.Spec.Source = corev1alpha1.SourceConfig{
 			Git: &corev1alpha1.Git{
 				URL:      "https://some.git/url",
-				Revision: "revision",
+				Revision: gitRevision,
 			},
 		}
 
@@ -147,11 +149,27 @@ func testImageBuilds(t *testing.T, when spec.G, it spec.S) {
 		it("sets git url and git revision when image source is git", func() {
 			build := image.Build(sourceResolver, builder, latestBuild, "", "", 27, "")
 			assert.Contains(t, build.Spec.Source.Git.URL, "https://some.git/url")
-			assert.Contains(t, build.Spec.Source.Git.Revision, "revision")
+			assert.Equal(t, gitRevision, build.Spec.Source.Git.Revision)
 			assert.Nil(t, build.Spec.Source.Blob)
 			assert.Nil(t, build.Spec.Source.Registry)
 		})
 
+		it("appends the git sha tag when a git source is present", func() {
+			image.Spec.Tag = "gcr.io/imagename/foo:test"
+			build := image.Build(sourceResolver, builder, latestBuild, "", "", 12, "")
+			assert.Contains(t, build.Spec.Tags, "gcr.io/imagename/foo:"+gitRevision)
+		})
+
+		it("appends the git sha tag even when the resolved git source is not marked as a commit", func() {
+			image.Spec.Tag = "gcr.io/imagename/foo:test"
+			previousType := sourceResolver.Status.Source.Git.Type
+			sourceResolver.Status.Source.Git.Type = corev1alpha1.Branch
+			defer func() { sourceResolver.Status.Source.Git.Type = previousType }()
+
+			build := image.Build(sourceResolver, builder, latestBuild, "", "", 12, "")
+			assert.Contains(t, build.Spec.Tags, "gcr.io/imagename/foo:"+gitRevision)
+		})
+
 		it("sets blob url when image source is blob", func() {
 			sourceResolver.Status.Source = corev1alpha1.ResolvedSourceConfig{
 				Blob: &corev1alpha1.ResolvedBlobSource{
@@ -180,15 +198,15 @@ func testImageBuilds(t *testing.T, when spec.G, it spec.S) {
 			image.Spec.Tag = "imagename/foo:test"
 			image.Spec.ImageTaggingStrategy = corev1alpha1.None
 			build := image.Build(sourceResolver, builder, latestBuild, "", "", 1, "")
-			require.Len(t, build.Spec.Tags, 1)
+			require.Len(t, build.Spec.Tags, 2)
 		})
 
 		it("with adds additional tags names", func() {
 			image.Spec.Tag = "imagename/foo:test"
 			image.Spec.AdditionalTags = []string{"imagename/foo:test2", "anotherimage/foo:test3"}
 			image.Spec.ImageTaggingStrategy = corev1alpha1.None
 			build := image.Build(sourceResolver, builder, latestBuild, "", "", 1, "")
-			require.Len(t, build.Spec.Tags, 3)
+			require.Len(t, build.Spec.Tags, 4)
 		})
 
 		it("generates a build with default process when set", func() {
@@ -202,29 +220,29 @@ func testImageBuilds(t *testing.T, when spec.G, it spec.S) {
 			it("with tag prefix if image name has a tag", func() {
 				image.Spec.Tag = "gcr.io/imagename/foo:test"
 				build := image.Build(sourceResolver, builder, latestBuild, "", "", 45, "")
-				require.Len(t, build.Spec.Tags, 2)
+				require.Len(t, build.Spec.Tags, 3)
 				require.Regexp(t, "gcr.io/imagename/foo:test-b45\\.\\d{8}\\.\\d{6}", build.Spec.Tags[1])
 			})
 
 			it("without tag prefix if image name has no provided tag", func() {
 				image.Spec.Tag = "gcr.io/imagename/notags"
 				build := image.Build(sourceResolver, builder, latestBuild, "", "", 1, "")
-				require.Len(t, build.Spec.Tags, 2)
+				require.Len(t, build.Spec.Tags, 3)
 				require.Regexp(t, "gcr.io/imagename/notags:b1\\.\\d{8}\\.\\d{6}", build.Spec.Tags[1])
 			})
 
 			it("with additional tags if provided", func() {
 				image.Spec.Tag = "gcr.io/imagename/tagged:latest"
 				image.Spec.AdditionalTags = []string{"imagename/foo:test2", "anotherimage/foo:test3"}
 				build := image.Build(sourceResolver, builder, latestBuild, "", "", 1, "")
-				require.Len(t, build.Spec.Tags, 4)
+				require.Len(t, build.Spec.Tags, 5)
 				require.Regexp(t, "gcr.io/imagename/tagged:b1\\.\\d{8}\\.\\d{6}", build.Spec.Tags[1])
 			})
 
 			it("without tag prefix if image name has the tag 'latest' provided", func() {
 				image.Spec.Tag = "gcr.io/imagename/tagged:latest"
 				build := image.Build(sourceResolver, builder, latestBuild, "", "", 1, "")
-				require.Len(t, build.Spec.Tags, 2)
+				require.Len(t, build.Spec.Tags, 3)
 				require.Regexp(t, "gcr.io/imagename/tagged:b1\\.\\d{8}\\.\\d{6}", build.Spec.Tags[1])
 			})
 		})