fix: further fixes for gracefully handling missing tag

Follows 1b37d2d5f5.

pkg/compose/compose.go

@@ -16,10 +16,10 @@ import (
 )
 
 // UpdateTag updates an image tag in-place on file system local compose files.
-func UpdateTag(pattern, image, tag, recipeName string) error {
+func UpdateTag(pattern, image, tag, recipeName string) (bool, error) {
 	composeFiles, err := filepath.Glob(pattern)
 	if err != nil {
-		return err
+		return false, err
 	}
 
 	logrus.Debugf("considering %s config(s) for tag update", strings.Join(composeFiles, ", "))
@@ -30,12 +30,12 @@ func UpdateTag(pattern, image, tag, recipeName string) error {
 		envSamplePath := path.Join(config.RECIPES_DIR, recipeName, ".env.sample")
 		sampleEnv, err := config.ReadEnv(envSamplePath)
 		if err != nil {
-			return err
+			return false, err
 		}
 
 		compose, err := loader.LoadComposefile(opts, sampleEnv)
 		if err != nil {
-			return err
+			return false, err
 		}
 
 		for _, service := range compose.Services {
@@ -45,24 +45,26 @@ func UpdateTag(pattern, image, tag, recipeName string) error {
 
 			img, _ := reference.ParseNormalizedNamed(service.Image)
 			if err != nil {
-				return err
+				return false, err
+			}
+
+			var composeTag string
+			switch img.(type) {
+			case reference.NamedTagged:
+				composeTag = img.(reference.NamedTagged).Tag()
+			default:
+				// unable to parse, typically image missing tag
+				return false, nil
 			}
 
 			composeImage := reference.Path(img)
-			if strings.Contains(composeImage, "library") {
-				// ParseNormalizedNamed prepends 'library' to images like nginx:<tag>,
-				// postgres:<tag>, i.e. images which do not have a username in the
-				// first position of the string
-				composeImage = strings.Split(composeImage, "/")[1]
-			}
-			composeTag := img.(reference.NamedTagged).Tag()
 
 			logrus.Debugf("parsed %s from %s", composeTag, service.Image)
 
 			if image == composeImage {
 				bytes, err := ioutil.ReadFile(composeFile)
 				if err != nil {
-					return err
+					return false, err
 				}
 
 				old := fmt.Sprintf("%s:%s", composeImage, composeTag)
@@ -72,13 +74,13 @@ func UpdateTag(pattern, image, tag, recipeName string) error {
 				logrus.Debugf("updating %s to %s in %s", old, new, compose.Filename)
 
 				if err := ioutil.WriteFile(compose.Filename, []byte(replacedBytes), 0764); err != nil {
-					return err
+					return true, err
 				}
 			}
 		}
 	}
 
-	return nil
+	return false, nil
 }
 
 // UpdateLabel updates a label in-place on file system local compose files.