diff --git a/openapi/oauth/oauth.go b/openapi/oauth/oauth.go
index 718b2452..ddb1ff2f 100644
--- a/openapi/oauth/oauth.go
+++ b/openapi/oauth/oauth.go
@@ -11,6 +11,9 @@ import (
 	"github.com/yaoapp/yao/share"
 )
 
+// OAuth is the global OAuth service
+var OAuth *Service = nil
+
 // Service OAuth service
 type Service struct {
 	config         *Config
@@ -147,6 +150,8 @@ func NewService(config *Config) (*Service, error) {
 		signingCerts:   signingCerts,
 	}
 
+	// Set the global OAuth service
+	OAuth = service
 	return service, nil
 }
 
@@ -165,6 +170,16 @@ func (s *Service) GetClientProvider() types.ClientProvider {
 	return s.clientProvider
 }
 
+// GetCache returns the cache for the service
+func (s *Service) GetCache() store.Store {
+	return s.cache
+}
+
+// GetStore returns the store for the service
+func (s *Service) GetStore() store.Store {
+	return s.store
+}
+
 // setConfigDefaults sets default values for configuration
 func setConfigDefaults(config *Config) error {
 	// Certificate defaults
diff --git a/openapi/signin/api.go b/openapi/signin/api.go
index 4f116094..493eece5 100644
--- a/openapi/signin/api.go
+++ b/openapi/signin/api.go
@@ -11,8 +11,8 @@ import (
 	"github.com/gin-gonic/gin"
 	"github.com/google/uuid"
 	"github.com/yaoapp/gou/session"
-	"github.com/yaoapp/gou/store"
 	"github.com/yaoapp/kun/log"
+	"github.com/yaoapp/yao/openapi/oauth"
 	"github.com/yaoapp/yao/openapi/oauth/types"
 	"github.com/yaoapp/yao/openapi/response"
 	"github.com/yaoapp/yao/openapi/utils"
@@ -193,6 +193,8 @@ func authback(c *gin.Context) {
 		userInfo, err = provider.GetUserInfo(tokenResponse.AccessToken, tokenResponse.TokenType)
 	}
 
+	// Create / Update / User then login (Generate access_token and id_token)
+
 	if err != nil {
 		errorResp := &response.ErrorResponse{
 			Code:             response.ErrInvalidRequest.Code,
@@ -293,8 +295,6 @@ func getOAuthAuthorizationURL(c *gin.Context) {
 	// Add scopes
 	if len(provider.Scopes) > 0 {
 		params.Add("scope", strings.Join(provider.Scopes, " "))
-	} else {
-		params.Add("scope", "openid profile email")
 	}
 
 	// Add response_mode if specified (required for Apple with name/email scopes)
@@ -398,30 +398,37 @@ func generateSessionID() string {
 	return session.ID()
 }
 
+// userInfoKey returns the key for the user info
+func userInfoKey(providerID, state string) string {
+	return fmt.Sprintf("signin:user_info:%s:%s", providerID, state)
+}
+
+// stateKey returns the key for the state
+func stateKey(providerID string) string {
+	return fmt.Sprintf("signin:state:%s", providerID)
+}
+
+// redirectURIKey returns the key for the redirect URI
+func redirectURIKey(providerID, state string) string {
+	return fmt.Sprintf("signin:redirect_uri:%s:%s", providerID, state)
+}
+
 // saveState saves the state to the session
 func saveState(providerID, sid, state string) error {
-	return session.Global().ID(sid).SetWithEx(fmt.Sprintf("oauth_state_%s", providerID), state, 20*time.Minute)
+	return session.Global().ID(sid).SetWithEx(stateKey(providerID), state, 20*time.Minute)
 }
 
 // saveRedirectURI saves the redirect URI to the session
 func saveRedirectURI(providerID, state, redirectURI string) error {
-	key := fmt.Sprintf("oauth_redirect_uri_%s_%s", providerID, state)
-	store, err := store.Get("__yao.oauth.cache")
-	if err != nil {
-		return err
-	}
-	store.Set(key, redirectURI, 20*time.Minute)
-	return nil
+	key := redirectURIKey(providerID, state)
+	store := oauth.OAuth.GetCache()
+	return store.Set(key, redirectURI, 20*time.Minute)
 }
 
 // getRedirectURI gets the redirect URI from the session
 func getRedirectURI(providerID, state string) (string, error) {
-	key := fmt.Sprintf("oauth_redirect_uri_%s_%s", providerID, state)
-	store, err := store.Get("__yao.oauth.cache")
-	if err != nil {
-		return "", err
-	}
-
+	key := redirectURIKey(providerID, state)
+	store := oauth.OAuth.GetCache()
 	value, ok := store.Get(key)
 	if !ok || value == nil {
 		return "", fmt.Errorf("redirect URI not found")
@@ -430,34 +437,22 @@ func getRedirectURI(providerID, state string) (string, error) {
 }
 
 func removeRedirectURI(providerID, state string) error {
-	key := fmt.Sprintf("oauth_redirect_uri_%s_%s", providerID, state)
-	store, err := store.Get("__yao.oauth.cache")
-	if err != nil {
-		return err
-	}
-	store.Del(key)
-	return nil
+	key := redirectURIKey(providerID, state)
+	store := oauth.OAuth.GetCache()
+	return store.Del(key)
 }
 
 // saveUserInfo saves the user info to cache (for form_post mode)
 func saveUserInfo(providerID, state, userInfo string) error {
-	key := fmt.Sprintf("oauth_user_info_%s_%s", providerID, state)
-	store, err := store.Get("__yao.oauth.cache")
-	if err != nil {
-		return err
-	}
-	store.Set(key, userInfo, 20*time.Minute)
-	return nil
+	key := userInfoKey(providerID, state)
+	store := oauth.OAuth.GetCache()
+	return store.Set(key, userInfo, 20*time.Minute)
 }
 
 // getUserInfo gets the user info from cache
 func getUserInfo(providerID, state string) (string, error) {
-	key := fmt.Sprintf("oauth_user_info_%s_%s", providerID, state)
-	store, err := store.Get("__yao.oauth.cache")
-	if err != nil {
-		return "", err
-	}
-
+	key := userInfoKey(providerID, state)
+	store := oauth.OAuth.GetCache()
 	value, ok := store.Get(key)
 	if !ok || value == nil {
 		return "", fmt.Errorf("user info not found")
@@ -467,18 +462,15 @@ func getUserInfo(providerID, state string) (string, error) {
 
 // removeUserInfo removes the user info from cache
 func removeUserInfo(providerID, state string) error {
-	key := fmt.Sprintf("oauth_user_info_%s_%s", providerID, state)
-	store, err := store.Get("__yao.oauth.cache")
-	if err != nil {
-		return err
-	}
-	store.Del(key)
-	return nil
+	key := userInfoKey(providerID, state)
+	store := oauth.OAuth.GetCache()
+	return store.Del(key)
 }
 
+// removeState removes the state from the session
 func removeState(providerID, sid string) error {
 	// Get the state from the session
-	state, err := session.Global().ID(sid).Get(fmt.Sprintf("oauth_state_%s", providerID))
+	state, err := session.Global().ID(sid).Get(stateKey(providerID))
 	if err != nil {
 		return err
 	}
@@ -493,12 +485,12 @@ func removeState(providerID, sid string) error {
 	removeRedirectURI(providerID, stateStr)
 	removeUserInfo(providerID, stateStr)
 
-	return session.Global().ID(sid).Del(fmt.Sprintf("oauth_state_%s", providerID))
+	return session.Global().ID(sid).Del(stateKey(providerID))
 }
 
 // validateState validates the state from the session
 func validateState(providerID, sid, state string) error {
-	value, err := session.Global().ID(sid).Get(fmt.Sprintf("oauth_state_%s", providerID))
+	value, err := session.Global().ID(sid).Get(stateKey(providerID))
 	if err != nil {
 		return err
 	}