Add possibility to build custom Kubernetes forks

Signed-off-by: Sascha Grunert <[email protected]>

gcb/release/cloudbuild.yaml

@@ -48,6 +48,9 @@ steps:
   - "TOOL_ORG=${_TOOL_ORG}"
   - "TOOL_REPO=${_TOOL_REPO}"
   - "TOOL_REF=${_TOOL_REF}"
+  - "K8S_ORG=${_K8S_ORG}"
+  - "K8S_REPO=${_K8S_REPO}"
+  - "K8S_REF=${_K8S_REF}"
   secretEnv:
   - GITHUB_TOKEN
   args:

gcb/stage/cloudbuild.yaml

@@ -49,6 +49,9 @@ steps:
   - "TOOL_ORG=${_TOOL_ORG}"
   - "TOOL_REPO=${_TOOL_REPO}"
   - "TOOL_REF=${_TOOL_REF}"
+  - "K8S_ORG=${_K8S_ORG}"
+  - "K8S_REPO=${_K8S_REPO}"
+  - "K8S_REF=${_K8S_REF}"
   secretEnv:
   - GITHUB_TOKEN
   - DOCKERHUB_TOKEN

pkg/anago/stage.go

@@ -136,6 +136,7 @@ type stageImpl interface {
 	CurrentBranch(repo *git.Repo) (string, error)
 	CommitEmpty(repo *git.Repo, msg string) error
 	Tag(repo *git.Repo, name, message string) error
+	Merge(repo *git.Repo, rev string) error
 	CheckReleaseBucket(options *build.Options) error
 	DockerHubLogin() error
 	MakeCross(version string) error
@@ -213,6 +214,10 @@ func (d *defaultStageImpl) Tag(repo *git.Repo, name, message string) error {
 	return repo.Tag(name, message)
 }
 
+func (d *defaultStageImpl) Merge(repo *git.Repo, rev string) error {
+	return repo.Merge(rev)
+}
+
 func (d *defaultStageImpl) MakeCross(version string) error {
 	return build.NewMake().MakeCross(version)
 }
@@ -437,6 +442,16 @@ func (d *DefaultStage) TagRepository() error {
 			}
 		}
 
+		// If a custom ref is provided, try to merge it into the release
+		// branch.
+		ref := release.GetK8sRef()
+		if ref != release.DefaultK8sRef {
+			logrus.Infof("Merging custom ref: %s", ref)
+			if err := d.impl.Merge(repo, git.Remotify(ref)); err != nil {
+				return errors.Wrap(err, "merge k8s ref")
+			}
+		}
+
 		// Tag the repository:
 		logrus.Infof("Tagging version %s", version)
 		if err := d.impl.Tag(

pkg/gcp/gcb/gcb.go

@@ -301,6 +301,10 @@ func (g *GCB) SetGCBSubstitutions(toolOrg, toolRepo, toolRef string) (map[string
 	gcbSubs["TOOL_REPO"] = toolRepo
 	gcbSubs["TOOL_REF"] = toolRef
 
+	gcbSubs["K8S_ORG"] = release.GetK8sOrg()
+	gcbSubs["K8S_REPO"] = release.GetK8sRepo()
+	gcbSubs["K8S_REF"] = release.GetK8sRef()
+
 	gcpUser := g.options.GcpUser
 	if gcpUser == "" {
 		var gcpUserErr error

pkg/gcp/gcb/gcb_test.go

@@ -188,6 +188,9 @@ func TestSetGCBSubstitutionsSuccess(t *testing.T) {
 				"MINOR_VERSION_TAG":      "17",
 				"PATCH_VERSION_TAG":      "0",
 				"KUBERNETES_VERSION_TAG": "1.17.0",
+				"K8S_ORG":                git.DefaultGithubOrg,
+				"K8S_REPO":               git.DefaultGithubRepo,
+				"K8S_REF":                git.DefaultRef,
 			},
 		},
 		{
@@ -213,6 +216,9 @@ func TestSetGCBSubstitutionsSuccess(t *testing.T) {
 				"MINOR_VERSION_TAG":      "33",
 				"PATCH_VERSION_TAG":      "7",
 				"KUBERNETES_VERSION_TAG": "1.33.7",
+				"K8S_ORG":                git.DefaultGithubOrg,
+				"K8S_REPO":               git.DefaultGithubRepo,
+				"K8S_REF":                git.DefaultRef,
 			},
 		},
 		{
@@ -237,6 +243,9 @@ func TestSetGCBSubstitutionsSuccess(t *testing.T) {
 				"MINOR_VERSION_TAG":      "15",
 				"KUBERNETES_VERSION_TAG": "1.15.0-rc.2",
 				"PATCH_VERSION_TAG":      "0",
+				"K8S_ORG":                git.DefaultGithubOrg,
+				"K8S_REPO":               git.DefaultGithubRepo,
+				"K8S_REF":                git.DefaultRef,
 			},
 		},
 		{
@@ -261,6 +270,9 @@ func TestSetGCBSubstitutionsSuccess(t *testing.T) {
 				"MINOR_VERSION_TAG":      "15",
 				"PATCH_VERSION_TAG":      "1",
 				"KUBERNETES_VERSION_TAG": "1.15.1",
+				"K8S_ORG":                git.DefaultGithubOrg,
+				"K8S_REPO":               git.DefaultGithubRepo,
+				"K8S_REF":                git.DefaultRef,
 			},
 		},
 		{
@@ -288,6 +300,9 @@ func TestSetGCBSubstitutionsSuccess(t *testing.T) {
 				"MINOR_VERSION_TAG":      "16",
 				"PATCH_VERSION_TAG":      "0",
 				"KUBERNETES_VERSION_TAG": "1.16.0",
+				"K8S_ORG":                git.DefaultGithubOrg,
+				"K8S_REPO":               git.DefaultGithubRepo,
+				"K8S_REF":                git.DefaultRef,
 			},
 		},
 		{
@@ -315,6 +330,9 @@ func TestSetGCBSubstitutionsSuccess(t *testing.T) {
 				"MINOR_VERSION_TAG":      "19",
 				"PATCH_VERSION_TAG":      "0",
 				"KUBERNETES_VERSION_TAG": "1.19.0-beta.0",
+				"K8S_ORG":                git.DefaultGithubOrg,
+				"K8S_REPO":               git.DefaultGithubRepo,
+				"K8S_REF":                git.DefaultRef,
 			},
 		},
 		{
@@ -339,6 +357,9 @@ func TestSetGCBSubstitutionsSuccess(t *testing.T) {
 				"MINOR_VERSION_TAG":      "18",
 				"KUBERNETES_VERSION_TAG": "1.18.6-rc.1",
 				"PATCH_VERSION_TAG":      "6",
+				"K8S_ORG":                git.DefaultGithubOrg,
+				"K8S_REPO":               git.DefaultGithubRepo,
+				"K8S_REF":                git.DefaultRef,
 			},
 		},
 		{
@@ -363,6 +384,9 @@ func TestSetGCBSubstitutionsSuccess(t *testing.T) {
 				"MINOR_VERSION_TAG":      "18",
 				"KUBERNETES_VERSION_TAG": "1.18.0-rc.1",
 				"PATCH_VERSION_TAG":      "0",
+				"K8S_ORG":                git.DefaultGithubOrg,
+				"K8S_REPO":               git.DefaultGithubRepo,
+				"K8S_REF":                git.DefaultRef,
 			},
 		},
 	}

pkg/release/branch_checker.go

@@ -61,7 +61,7 @@ func (r *BranchChecker) NeedsCreation(
 	logrus.Infof("Checking if branch %s exists on remote", branch)
 
 	output, err := r.impl.LSRemoteExec(
-		git.GetDefaultKubernetesRepoURL(),
+		git.GetRepoURL(GetK8sOrg(), GetK8sRepo(), false),
 		fmt.Sprintf("refs/heads/%s", branch),
 	)
 	if err != nil {

pkg/release/release.go

@@ -47,6 +47,11 @@ const (
 	DefaultToolRepo = "release"
 	DefaultToolRef  = git.DefaultBranch
 	DefaultToolOrg  = git.DefaultGithubOrg
+
+	DefaultK8sOrg  = git.DefaultGithubOrg
+	DefaultK8sRepo = git.DefaultGithubRepo
+	DefaultK8sRef  = git.DefaultRef
+
 	// TODO(vdf): Need to reference K8s Infra project here
 	DefaultKubernetesStagingProject = "kubernetes-release-test"
 	DefaultRelengStagingProject     = "k8s-staging-releng"
@@ -176,6 +181,32 @@ func GetToolRef() string {
 	return env.Default("TOOL_REF", DefaultToolRef)
 }
 
+// GetK8sOrg checks if the 'K8S_ORG' environment variable is set.
+// If 'K8S_ORG' is non-empty, it returns the value. Otherwise, it returns DefaultK8sOrg.
+func GetK8sOrg() string {
+	return env.Default("K8S_ORG", DefaultK8sOrg)
+}
+
+// GetK8sRepo checks if the 'K8S_REPO' environment variable is set.
+// If 'K8S_REPO' is non-empty, it returns the value. Otherwise, it returns DefaultK8sRepo.
+func GetK8sRepo() string {
+	return env.Default("K8S_REPO", DefaultK8sRepo)
+}
+
+// GetK8sRef checks if the 'K8S_REF' environment variable is set.
+// If 'K8S_REF' is non-empty, it returns the value. Otherwise, it returns DefaultK8sRef.
+func GetK8sRef() string {
+	return env.Default("K8S_REF", DefaultK8sRef)
+}
+
+// IsDefaultK8sUpstream returns true if GetK8sOrg(), GetK8sRepo() and
+// GetK8sRef() point to their default values.
+func IsDefaultK8sUpstream() bool {
+	return GetK8sOrg() == DefaultK8sOrg &&
+		GetK8sRepo() == DefaultK8sRepo &&
+		GetK8sRef() == DefaultK8sRef
+}
+
 // BuiltWithBazel determines whether the most recent Kubernetes release was built with Bazel.
 func BuiltWithBazel(workDir string) (bool, error) {
 	bazelBuild := filepath.Join(workDir, BazelBuildDir, ReleaseTarsPath, KubernetesTar)