From 69dfd47f743101ac0b6921e8523f3b15188cb59b Mon Sep 17 00:00:00 2001
From: Jay <jay@sarvika.com>
Date: Mon, 24 Jan 2022 14:28:06 +0530
Subject: [PATCH] Added an error handler that is invoked before s.redirectError

---
 server/handler.go       |  3 +++
 server/server.go        | 16 +++++++++++++---
 server/server_config.go |  8 ++++++--
 3 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/server/handler.go b/server/handler.go
index ad2cc18..ffdb6ec 100755
--- a/server/handler.go
+++ b/server/handler.go
@@ -36,6 +36,9 @@ type (
 	// InternalErrorHandler internal error handing
 	InternalErrorHandler func(err error) (re *errors.Response)
 
+	// PreRedirectErrorHandler is used to override "redirect-on-error" behavior
+	PreRedirectErrorHandler func(w http.ResponseWriter, req *AuthorizeRequest, err error) error
+
 	// AuthorizeScopeHandler set the authorized scope
 	AuthorizeScopeHandler func(w http.ResponseWriter, r *http.Request) (scope string, err error)
 
diff --git a/server/server.go b/server/server.go
index 0fb18e7..3df5ca1 100755
--- a/server/server.go
+++ b/server/server.go
@@ -48,6 +48,7 @@ type Server struct {
 	UserAuthorizationHandler     UserAuthorizationHandler
 	PasswordAuthorizationHandler PasswordAuthorizationHandler
 	RefreshingValidationHandler  RefreshingValidationHandler
+	PreRedirectErrorHandler      PreRedirectErrorHandler
 	RefreshingScopeHandler       RefreshingScopeHandler
 	ResponseErrorHandler         ResponseErrorHandler
 	InternalErrorHandler         InternalErrorHandler
@@ -57,10 +58,19 @@ type Server struct {
 	ResponseTokenHandler         ResponseTokenHandler
 }
 
+func (s *Server) handleError(w http.ResponseWriter, req *AuthorizeRequest, err error) error {
+	if fn := s.PreRedirectErrorHandler; fn != nil {
+		return fn(w, req, err)
+	}
+
+	return s.redirectError(w, req, err)
+}
+
 func (s *Server) redirectError(w http.ResponseWriter, req *AuthorizeRequest, err error) error {
 	if req == nil {
 		return err
 	}
+
 	data, _, _ := s.GetErrorData(err)
 	return s.redirect(w, req, data)
 }
@@ -257,13 +267,13 @@ func (s *Server) HandleAuthorizeRequest(w http.ResponseWriter, r *http.Request)
 
 	req, err := s.ValidationAuthorizeRequest(r)
 	if err != nil {
-		return s.redirectError(w, req, err)
+		return s.handleError(w, req, err)
 	}
 
 	// user authorization
 	userID, err := s.UserAuthorizationHandler(w, r)
 	if err != nil {
-		return s.redirectError(w, req, err)
+		return s.handleError(w, req, err)
 	} else if userID == "" {
 		return nil
 	}
@@ -290,7 +300,7 @@ func (s *Server) HandleAuthorizeRequest(w http.ResponseWriter, r *http.Request)
 
 	ti, err := s.GetAuthorizeToken(ctx, req)
 	if err != nil {
-		return s.redirectError(w, req, err)
+		return s.handleError(w, req, err)
 	}
 
 	// If the redirect URI is empty, the default domain provided by the client is used.
diff --git a/server/server_config.go b/server/server_config.go
index 934c543..d4f0404 100644
--- a/server/server_config.go
+++ b/server/server_config.go
@@ -59,7 +59,6 @@ func (s *Server) SetRefreshingValidationHandler(handler RefreshingValidationHand
 	s.RefreshingValidationHandler = handler
 }
 
-
 // SetResponseErrorHandler response error handling
 func (s *Server) SetResponseErrorHandler(handler ResponseErrorHandler) {
 	s.ResponseErrorHandler = handler
@@ -70,6 +69,11 @@ func (s *Server) SetInternalErrorHandler(handler InternalErrorHandler) {
 	s.InternalErrorHandler = handler
 }
 
+// SetPreRedirectErrorHandler sets the PreRedirectErrorHandler in current Server instance
+func (s *Server) SetPreRedirectErrorHandler(handler PreRedirectErrorHandler) {
+	s.PreRedirectErrorHandler = handler
+}
+
 // SetExtensionFieldsHandler in response to the access token with the extension of the field
 func (s *Server) SetExtensionFieldsHandler(handler ExtensionFieldsHandler) {
 	s.ExtensionFieldsHandler = handler
@@ -88,4 +92,4 @@ func (s *Server) SetAuthorizeScopeHandler(handler AuthorizeScopeHandler) {
 // SetResponseTokenHandler response token handing
 func (s *Server) SetResponseTokenHandler(handler ResponseTokenHandler) {
 	s.ResponseTokenHandler = handler
-}
\ No newline at end of file
+}