add a private function

Signed-off-by: Lixia (Sylvia) Lei <[email protected]>

registry/remote/auth/client.go

@@ -187,12 +187,7 @@ func (c *Client) Do(originalReq *http.Request) (*http.Response, error) {
 				req.Header.Set("Authorization", "Basic "+token)
 			}
 		case SchemeBearer:
-			// merge per-host scopes with global scopes
-			scopes := GetScopesForHost(ctx, host)
-			if moreScopes := GetScopes(ctx); len(moreScopes) > 0 {
-				scopes = append(scopes, moreScopes...)
-				scopes = CleanScopes(scopes)
-			}
+			scopes := getAllScopesForHost(ctx, host)
 			attemptedKey = strings.Join(scopes, " ")
 			token, err := cache.GetToken(ctx, host, SchemeBearer, attemptedKey)
 			if err == nil {
@@ -228,18 +223,10 @@ func (c *Client) Do(originalReq *http.Request) (*http.Response, error) {
 	case SchemeBearer:
 		resp.Body.Close()
 
-		scopes := GetScopesForHost(ctx, host)
-		cleanScopeLen := len(scopes)
-		if moreScopes := GetScopes(ctx); len(moreScopes) > 0 {
-			// merge per-host scopes with global scopes
-			scopes = append(scopes, moreScopes...)
-		}
+		scopes := getAllScopesForHost(ctx, host)
 		if paramScope := params["scope"]; paramScope != "" {
 			// merge hinted scopes with challenged scopes
 			scopes = append(scopes, strings.Split(paramScope, " ")...)
-		}
-		if len(scopes) > cleanScopeLen {
-			// re-clean the scopes
 			scopes = CleanScopes(scopes)
 		}
 		key := strings.Join(scopes, " ")

registry/remote/auth/scope.go

@@ -163,14 +163,32 @@ func AppendScopesForHost(ctx context.Context, host string, scopes ...string) con
 }
 
 // GetScopesForHost returns the scopes in the context for the given host,
-// excluding the global scopes added by [WithScopes] and [AppendScopes].
+// excluding global scopes added by [WithScopes] and [AppendScopes].
 func GetScopesForHost(ctx context.Context, host string) []string {
 	if scopes, ok := ctx.Value(scopesForHostContextKey(host)).([]string); ok {
 		return slices.Clone(scopes)
 	}
 	return nil
 }
 
+// getAllScopesForHost returns the scopes in the context for the given host,
+// including global scopes added by [WithScopes] and [AppendScopes].
+func getAllScopesForHost(ctx context.Context, host string) []string {
+	scopes := GetScopesForHost(ctx, host)
+	globalScopes := GetScopes(ctx)
+
+	switch {
+	case len(scopes) == 0:
+		return globalScopes
+	case len(globalScopes) == 0:
+		return scopes
+	default:
+		// re-clean the scopes
+		allScopes := append(scopes, globalScopes...)
+		return CleanScopes(allScopes)
+	}
+}
+
 // CleanScopes merges and sort the actions in ascending order if the scopes have
 // the same resource type and name. The final scopes are sorted in ascending
 // order. In other words, the scopes passed in are de-duplicated and sorted.