Fix BuildImageName for digest mode

Fixes an issue where a custom port was used in the image name
and the wrong part of the image name was replaced.

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <[email protected]>

Author: alexellis

builder/build.go

@@ -68,6 +68,7 @@ func BuildImage(image string, handler string, functionName string, language stri
 		}
 
 		imageName := schema.BuildImageName(tagFormat, image, version, branch)
+
 		fmt.Printf("Building: %s with %s template. Please wait..\n", imageName, language)
 
 		if remoteBuilder != "" {

schema/image.go

@@ -71,7 +71,7 @@ func (i *BuildFormat) Set(value string) error {
 func BuildImageName(format BuildFormat, image string, version string, branch string) string {
 	imageVal := image
 	splitImage := strings.Split(image, "/")
-	if strings.Contains(splitImage[len(splitImage)-1], ":") == false {
+	if !strings.Contains(splitImage[len(splitImage)-1], ":") {
 		imageVal += ":latest"
 	}
 
@@ -85,13 +85,13 @@ func BuildImageName(format BuildFormat, image string, version string, branch str
 		// the describe describe value
 		return imageVal + "-" + version
 	case DigestFormat:
-		baseImage, _, found := strings.Cut(imageVal, ":")
-		if !found {
+
+		if lastIndex := strings.LastIndex(imageVal, ":"); lastIndex > -1 {
+			baseImage := imageVal[:lastIndex]
+			return fmt.Sprintf("%s:%s", baseImage, version)
+		} else {
 			return imageVal + "-" + version
 		}
-
-		return fmt.Sprintf("%s:%s", baseImage, version)
-
 	default:
 		return imageVal
 	}

schema/image_test.go

@@ -20,6 +20,16 @@ func Test_BuildImageName_DefaultFormat_WithCustomServerPort(t *testing.T) {
 	}
 }
 
+func Test_BuildImageName_Localhost_SingleLevelDigestFormat(t *testing.T) {
+
+	want := "localhost:5001/pydict:851a77095527c1c703905ddb5f94780a"
+	got := BuildImageName(DigestFormat, "localhost:5001/pydict:latest", "851a77095527c1c703905ddb5f94780a", "")
+
+	if got != want {
+		t.Errorf("BuildImageName want: \"%s\", got: \"%s\"", want, got)
+	}
+}
+
 func Test_BuildImageName_SHAFormat(t *testing.T) {
 	want := "img:latest-ef384"
 	got := BuildImageName(SHAFormat, "img", "ef384", "master")