[krel] gcbmgr: Dynamically retrieve build version from CI markers

Signed-off-by: Stephen Augustus <saugustus@vmware.com>

cmd/krel/cmd/gcbmgr.go

@@ -109,7 +109,7 @@ func init() {
 	gcbmgrCmd.PersistentFlags().StringVar(
 		&gcbmgrOpts.buildVersion,
 		"build-version",
-		"FAKE+BUILD+POINT",
+		"",
 		"Build version",
 	)
 
@@ -308,25 +308,33 @@ func setGCBSubstitutions(o *gcbmgrOptions) (map[string]string, error) {
 		gcbSubs["RC"] = ""
 	}
 
+	branch := o.branch
+	if branch == "" {
+		return gcbSubs, errors.New("Release branch must be set to continue")
+	}
+
+	gcbSubs["RELEASE_BRANCH"] = branch
+
 	// TODO: Remove once we remove support for --built-at-head.
 	gcbSubs["BUILD_AT_HEAD"] = ""
 
-	buildpoint := o.buildVersion
+	buildVersion := o.buildVersion
+	if buildVersion == "" {
+		var versionErr error
+		buildVersion, versionErr = release.GetCIKubeVersion(o.branch)
+		if versionErr != nil {
+			return gcbSubs, versionErr
+		}
+	}
+
+	buildpoint := buildVersion
 	buildpoint = strings.ReplaceAll(buildpoint, "+", "-")
 	gcbSubs["BUILD_POINT"] = buildpoint
 
 	// TODO: Add conditionals for find_green_build
-	buildVersion := o.buildVersion
 	buildVersion = fmt.Sprintf("--buildversion=%s", buildVersion)
 	gcbSubs["BUILDVERSION"] = buildVersion
 
-	branch := o.branch
-	if branch == "" {
-		return gcbSubs, errors.New("Release branch must be set to continue")
-	}
-
-	gcbSubs["RELEASE_BRANCH"] = branch
-
 	kubecrossBranches := []string{
 		branch,
 		"master",

cmd/krel/cmd/gcbmgr_test.go

@@ -110,9 +110,7 @@ func TestSetGCBSubstitutionsSuccess(t *testing.T) {
 				gcpUser:     "test-user",
 			},
 			expected: map[string]string{
-				"BUILDVERSION":   "--buildversion=",
 				"BUILD_AT_HEAD":  "",
-				"BUILD_POINT":    "",
 				"OFFICIAL":       "",
 				"OFFICIAL_TAG":   "",
 				"RC":             "",
@@ -131,9 +129,7 @@ func TestSetGCBSubstitutionsSuccess(t *testing.T) {
 				gcpUser:     "test-user",
 			},
 			expected: map[string]string{
-				"BUILDVERSION":   "--buildversion=",
 				"BUILD_AT_HEAD":  "",
-				"BUILD_POINT":    "",
 				"OFFICIAL":       "",
 				"OFFICIAL_TAG":   "",
 				"RC":             "--rc",
@@ -152,9 +148,7 @@ func TestSetGCBSubstitutionsSuccess(t *testing.T) {
 				gcpUser:     "test-user",
 			},
 			expected: map[string]string{
-				"BUILDVERSION":   "--buildversion=",
 				"BUILD_AT_HEAD":  "",
-				"BUILD_POINT":    "",
 				"OFFICIAL":       "--official",
 				"OFFICIAL_TAG":   "official",
 				"RC":             "",
@@ -176,9 +170,7 @@ func TestSetGCBSubstitutionsSuccess(t *testing.T) {
 			toolRepo:   "best-tools",
 			toolBranch: "tool-branch",
 			expected: map[string]string{
-				"BUILDVERSION":   "--buildversion=",
 				"BUILD_AT_HEAD":  "",
-				"BUILD_POINT":    "",
 				"OFFICIAL":       "--official",
 				"OFFICIAL_TAG":   "official",
 				"RC":             "",
@@ -239,7 +231,7 @@ func dropDynamicSubstitutions(orig map[string]string) (result map[string]string)
 	result = orig
 
 	for k := range result {
-		if k == "GCP_USER_TAG" || k == "KUBE_CROSS_VERSION" {
+		if k == "BUILDVERSION" || k == "BUILD_POINT" || k == "GCP_USER_TAG" || k == "KUBE_CROSS_VERSION" {
 			delete(result, k)
 		}
 	}