normalize gke versions to be valid.

kubetest2-gke/deployer/build.go

@@ -18,6 +18,7 @@ package deployer
 
 import (
 	"fmt"
+	"regexp"
 	"strings"
 )
 
@@ -30,7 +31,11 @@ func (d *deployer) Build() error {
 		return err
 	}
 	version = strings.TrimPrefix(version, "v")
-	version += ".0+" + d.commonOptions.RunID()
+	if version, err = normalizeVersion(version); err != nil {
+		return err
+	}
+	// append the kubetest2 run id
+	version += "+" + d.commonOptions.RunID()
 	if d.BuildOptions.StageLocation != "" {
 		if err := d.BuildOptions.Stage(version); err != nil {
 			return fmt.Errorf("error staging build: %v", err)
@@ -47,3 +52,31 @@ func (d *deployer) verifyBuildFlags() error {
 	d.BuildOptions.RepoRoot = d.RepoRoot
 	return d.BuildOptions.Validate()
 }
+
+// ensure that the version is a valid gke version
+func normalizeVersion(version string) (string, error) {
+	// (1.18.10)(-gke)(.601.123)(+existingSuffix)
+	// capture repeated occurrences of group 3 and don't capture just last
+	re, err := regexp.Compile(`(\d\.\d+\.\d*)(-\w+)?((?:\.\d+)*)(\+.*)*`)
+	if err != nil {
+		return "", err
+	}
+	matches := re.FindStringSubmatch(version)
+	if matches == nil || len(matches) != 5 {
+		return "", fmt.Errorf("%q is not a valid gke version", version)
+	}
+	fmt.Println(matches)
+	// get the core version as is
+	finalVersion := matches[1]
+	// force append -gke, ignore alpha,beta
+	finalVersion += "-gke"
+	// add the optional patch number or .0
+	if matches[3] == "" {
+		finalVersion += ".0"
+	} else {
+		finalVersion += matches[3]
+	}
+	// append the optional suffix as is
+	finalVersion += matches[4]
+	return finalVersion, nil
+}