From 68d9245129be0bcc5e80c488a23084006a95983c Mon Sep 17 00:00:00 2001
From: chrislu <chris.lu@gmail.com>
Date: Mon, 14 Jul 2025 23:40:25 -0700
Subject: [PATCH] refactor

---
 weed/s3api/cors/middleware.go | 92 ++++++++++++++---------------------
 1 file changed, 36 insertions(+), 56 deletions(-)

diff --git a/weed/s3api/cors/middleware.go b/weed/s3api/cors/middleware.go
index a0e5a362c..14ff32355 100644
--- a/weed/s3api/cors/middleware.go
+++ b/weed/s3api/cors/middleware.go
@@ -35,97 +35,77 @@ func NewMiddleware(storage *Storage, bucketChecker BucketChecker, corsConfigGett
 }
 
 // evaluateCORSRequest performs the common CORS request evaluation logic
-func (m *Middleware) evaluateCORSRequest(w http.ResponseWriter, r *http.Request) (*CORSResponse, bool) {
+// Returns: (corsResponse, responseWritten, shouldContinue)
+// - corsResponse: the CORS response if evaluation succeeded
+// - responseWritten: true if an error response was already written
+// - shouldContinue: true if the request should continue to the next handler
+func (m *Middleware) evaluateCORSRequest(w http.ResponseWriter, r *http.Request) (*CORSResponse, bool, bool) {
 	// Parse CORS request
 	corsReq := ParseRequest(r)
 	if corsReq.Origin == "" {
 		// Not a CORS request
-		return nil, false
+		return nil, false, true
 	}
 
 	// Extract bucket from request
 	bucket, _ := s3_constants.GetBucketAndObject(r)
 	if bucket == "" {
-		return nil, false
+		return nil, false, true
 	}
 
 	// Check if bucket exists
 	if err := m.bucketChecker.CheckBucket(r, bucket); err != s3err.ErrNone {
-		s3err.WriteErrorResponse(w, r, err)
-		return nil, true // Return true to indicate response was written
+		// For non-existent buckets, let the normal handler deal with it
+		return nil, false, true
 	}
 
 	// Load CORS configuration from cache
 	config, errCode := m.corsConfigGetter.GetCORSConfiguration(bucket)
 	if errCode != s3err.ErrNone || config == nil {
-		s3err.WriteErrorResponse(w, r, s3err.ErrAccessDenied)
-		return nil, true // Return true to indicate response was written
+		// No CORS configuration, handle based on request type
+		if corsReq.IsPreflightRequest {
+			// Preflight request without CORS config should fail
+			s3err.WriteErrorResponse(w, r, s3err.ErrAccessDenied)
+			return nil, true, false // Response written, don't continue
+		}
+		// Non-preflight request, continue normally
+		return nil, false, true
 	}
 
 	// Evaluate CORS request
 	corsResp, err := EvaluateRequest(config, corsReq)
 	if err != nil {
 		glog.V(3).Infof("CORS evaluation failed for bucket %s: %v", bucket, err)
-		s3err.WriteErrorResponse(w, r, s3err.ErrAccessDenied)
-		return nil, true // Return true to indicate response was written
+		if corsReq.IsPreflightRequest {
+			// Preflight request that doesn't match CORS rules should fail
+			s3err.WriteErrorResponse(w, r, s3err.ErrAccessDenied)
+			return nil, true, false // Response written, don't continue
+		}
+		// Non-preflight request, continue normally but without CORS headers
+		return nil, false, true
 	}
 
-	return corsResp, false
+	return corsResp, false, false
 }
 
 // Handler returns the CORS middleware handler
 func (m *Middleware) Handler(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		// Check if this is a CORS request
-		corsReq := ParseRequest(r)
-		if corsReq.Origin == "" {
-			// Not a CORS request, continue normally
-			next.ServeHTTP(w, r)
-			return
-		}
-
-		// Extract bucket from request
-		bucket, _ := s3_constants.GetBucketAndObject(r)
-		if bucket == "" {
-			// No bucket in request, continue normally
-			next.ServeHTTP(w, r)
+		// Use the common evaluation logic
+		corsResp, responseWritten, shouldContinue := m.evaluateCORSRequest(w, r)
+		if responseWritten {
+			// Response was already written (error case)
 			return
 		}
 
-		// Check if bucket exists
-		if err := m.bucketChecker.CheckBucket(r, bucket); err != s3err.ErrNone {
-			// Bucket doesn't exist, let the normal handler deal with it
+		if shouldContinue {
+			// Continue with normal request processing
 			next.ServeHTTP(w, r)
 			return
 		}
 
-		// Load CORS configuration from cache
-		config, errCode := m.corsConfigGetter.GetCORSConfiguration(bucket)
-		if errCode != s3err.ErrNone || config == nil {
-			// No CORS configuration, handle based on request type
-			if corsReq.IsPreflightRequest {
-				// Preflight request without CORS config should fail
-				s3err.WriteErrorResponse(w, r, s3err.ErrAccessDenied)
-				return
-			}
-			// Non-preflight request, continue normally
-			next.ServeHTTP(w, r)
-			return
-		}
-
-		// Evaluate CORS request
-		corsResp, err := EvaluateRequest(config, corsReq)
-		if err != nil {
-			glog.V(3).Infof("CORS evaluation failed for bucket %s: %v", bucket, err)
-			if corsReq.IsPreflightRequest {
-				// Preflight request that doesn't match CORS rules should fail
-				s3err.WriteErrorResponse(w, r, s3err.ErrAccessDenied)
-				return
-			}
-			// Non-preflight request, continue normally but without CORS headers
-			next.ServeHTTP(w, r)
-			return
-		}
+		// Parse request to check if it's a preflight request
+		corsReq := ParseRequest(r)
 
 		// Apply CORS headers to response
 		ApplyHeaders(w, corsResp)
@@ -145,14 +125,14 @@ func (m *Middleware) Handler(next http.Handler) http.Handler {
 // HandleOptionsRequest handles OPTIONS requests for CORS preflight
 func (m *Middleware) HandleOptionsRequest(w http.ResponseWriter, r *http.Request) {
 	// Use the common evaluation logic
-	corsResp, responseWritten := m.evaluateCORSRequest(w, r)
+	corsResp, responseWritten, shouldContinue := m.evaluateCORSRequest(w, r)
 	if responseWritten {
 		// Response was already written (error case)
 		return
 	}
 
-	if corsResp == nil {
-		// Not a CORS request
+	if shouldContinue || corsResp == nil {
+		// Not a CORS request or should continue normally
 		w.WriteHeader(http.StatusOK)
 		return
 	}