diff --git a/weed/s3api/s3api_server.go b/weed/s3api/s3api_server.go
index 8c2c4f8f3..53d99055c 100644
--- a/weed/s3api/s3api_server.go
+++ b/weed/s3api/s3api_server.go
@@ -24,6 +24,10 @@ import (
 	"google.golang.org/grpc"
 )
 
+const (
+	BucketPathTpl = "/{object:[a-z0-9][a-z0-9-]+[a-z0-9]}"
+)
+
 type S3ApiServerOption struct {
 	Filer                     pb.ServerAddress
 	Port                      int
@@ -163,55 +167,55 @@ func (s3a *S3ApiServer) registerRouter(router *mux.Router) {
 		// objects with query
 
 		// CopyObjectPart
-		bucket.Methods(http.MethodPut).Path("/{object:.+}").HeadersRegexp("X-Amz-Copy-Source", `.*?(\/|%2F).*?`).HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.CopyObjectPartHandler, ACTION_WRITE)), "PUT")).Queries("partNumber", "{partNumber:[0-9]+}", "uploadId", "{uploadId:.*}")
+		bucket.Methods(http.MethodPut).Path(BucketPathTpl).HeadersRegexp("X-Amz-Copy-Source", `.*?(\/|%2F).*?`).HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.CopyObjectPartHandler, ACTION_WRITE)), "PUT")).Queries("partNumber", "{partNumber:[0-9]+}", "uploadId", "{uploadId:.*}")
 		// PutObjectPart
-		bucket.Methods(http.MethodPut).Path("/{object:.+}").HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.PutObjectPartHandler, ACTION_WRITE)), "PUT")).Queries("partNumber", "{partNumber:[0-9]+}", "uploadId", "{uploadId:.*}")
+		bucket.Methods(http.MethodPut).Path(BucketPathTpl).HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.PutObjectPartHandler, ACTION_WRITE)), "PUT")).Queries("partNumber", "{partNumber:[0-9]+}", "uploadId", "{uploadId:.*}")
 		// CompleteMultipartUpload
-		bucket.Methods(http.MethodPost).Path("/{object:.+}").HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.CompleteMultipartUploadHandler, ACTION_WRITE)), "POST")).Queries("uploadId", "{uploadId:.*}")
+		bucket.Methods(http.MethodPost).Path(BucketPathTpl).HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.CompleteMultipartUploadHandler, ACTION_WRITE)), "POST")).Queries("uploadId", "{uploadId:.*}")
 		// NewMultipartUpload
-		bucket.Methods(http.MethodPost).Path("/{object:.+}").HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.NewMultipartUploadHandler, ACTION_WRITE)), "POST")).Queries("uploads", "")
+		bucket.Methods(http.MethodPost).Path(BucketPathTpl).HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.NewMultipartUploadHandler, ACTION_WRITE)), "POST")).Queries("uploads", "")
 		// AbortMultipartUpload
-		bucket.Methods(http.MethodDelete).Path("/{object:.+}").HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.AbortMultipartUploadHandler, ACTION_WRITE)), "DELETE")).Queries("uploadId", "{uploadId:.*}")
+		bucket.Methods(http.MethodDelete).Path(BucketPathTpl).HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.AbortMultipartUploadHandler, ACTION_WRITE)), "DELETE")).Queries("uploadId", "{uploadId:.*}")
 		// ListObjectParts
-		bucket.Methods(http.MethodGet).Path("/{object:.+}").HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.ListObjectPartsHandler, ACTION_READ)), "GET")).Queries("uploadId", "{uploadId:.*}")
+		bucket.Methods(http.MethodGet).Path(BucketPathTpl).HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.ListObjectPartsHandler, ACTION_READ)), "GET")).Queries("uploadId", "{uploadId:.*}")
 		// ListMultipartUploads
 		bucket.Methods(http.MethodGet).HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.ListMultipartUploadsHandler, ACTION_READ)), "GET")).Queries("uploads", "")
 
 		// GetObjectTagging
-		bucket.Methods(http.MethodGet).Path("/{object:.+}").HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.GetObjectTaggingHandler, ACTION_READ)), "GET")).Queries("tagging", "")
+		bucket.Methods(http.MethodGet).Path(BucketPathTpl).HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.GetObjectTaggingHandler, ACTION_READ)), "GET")).Queries("tagging", "")
 		// PutObjectTagging
-		bucket.Methods(http.MethodPut).Path("/{object:.+}").HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.PutObjectTaggingHandler, ACTION_TAGGING)), "PUT")).Queries("tagging", "")
+		bucket.Methods(http.MethodPut).Path(BucketPathTpl).HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.PutObjectTaggingHandler, ACTION_TAGGING)), "PUT")).Queries("tagging", "")
 		// DeleteObjectTagging
-		bucket.Methods(http.MethodDelete).Path("/{object:.+}").HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.DeleteObjectTaggingHandler, ACTION_TAGGING)), "DELETE")).Queries("tagging", "")
+		bucket.Methods(http.MethodDelete).Path(BucketPathTpl).HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.DeleteObjectTaggingHandler, ACTION_TAGGING)), "DELETE")).Queries("tagging", "")
 
 		// PutObjectACL
-		bucket.Methods(http.MethodPut).Path("/{object:.+}").HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.PutObjectAclHandler, ACTION_WRITE_ACP)), "PUT")).Queries("acl", "")
+		bucket.Methods(http.MethodPut).Path(BucketPathTpl).HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.PutObjectAclHandler, ACTION_WRITE_ACP)), "PUT")).Queries("acl", "")
 		// PutObjectRetention
-		bucket.Methods(http.MethodPut).Path("/{object:.+}").HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.PutObjectRetentionHandler, ACTION_WRITE)), "PUT")).Queries("retention", "")
+		bucket.Methods(http.MethodPut).Path(BucketPathTpl).HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.PutObjectRetentionHandler, ACTION_WRITE)), "PUT")).Queries("retention", "")
 		// PutObjectLegalHold
-		bucket.Methods(http.MethodPut).Path("/{object:.+}").HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.PutObjectLegalHoldHandler, ACTION_WRITE)), "PUT")).Queries("legal-hold", "")
+		bucket.Methods(http.MethodPut).Path(BucketPathTpl).HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.PutObjectLegalHoldHandler, ACTION_WRITE)), "PUT")).Queries("legal-hold", "")
 		// PutObjectLockConfiguration
-		bucket.Methods(http.MethodPut).Path("/{object:.+}").HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.PutObjectLockConfigurationHandler, ACTION_WRITE)), "PUT")).Queries("object-lock", "")
+		bucket.Methods(http.MethodPut).Path(BucketPathTpl).HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.PutObjectLockConfigurationHandler, ACTION_WRITE)), "PUT")).Queries("object-lock", "")
 
 		// GetObjectACL
-		bucket.Methods(http.MethodGet).Path("/{object:.+}").HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.GetObjectAclHandler, ACTION_READ_ACP)), "GET")).Queries("acl", "")
+		bucket.Methods(http.MethodGet).Path(BucketPathTpl).HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.GetObjectAclHandler, ACTION_READ_ACP)), "GET")).Queries("acl", "")
 
 		// objects with query
 
 		// raw objects
 
 		// HeadObject
-		bucket.Methods(http.MethodHead).Path("/{object:.+}").HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.HeadObjectHandler, ACTION_READ)), "GET"))
+		bucket.Methods(http.MethodHead).Path(BucketPathTpl).HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.HeadObjectHandler, ACTION_READ)), "GET"))
 
 		// GetObject, but directory listing is not supported
-		bucket.Methods(http.MethodGet).Path("/{object:.+}").HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.GetObjectHandler, ACTION_READ)), "GET"))
+		bucket.Methods(http.MethodGet).Path(BucketPathTpl).HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.GetObjectHandler, ACTION_READ)), "GET"))
 
 		// CopyObject
-		bucket.Methods(http.MethodPut).Path("/{object:.+}").HeadersRegexp("X-Amz-Copy-Source", ".*?(\\/|%2F).*?").HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.CopyObjectHandler, ACTION_WRITE)), "COPY"))
+		bucket.Methods(http.MethodPut).Path(BucketPathTpl).HeadersRegexp("X-Amz-Copy-Source", ".*?(\\/|%2F).*?").HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.CopyObjectHandler, ACTION_WRITE)), "COPY"))
 		// PutObject
-		bucket.Methods(http.MethodPut).Path("/{object:.+}").HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.PutObjectHandler, ACTION_WRITE)), "PUT"))
+		bucket.Methods(http.MethodPut).Path(BucketPathTpl).HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.PutObjectHandler, ACTION_WRITE)), "PUT"))
 		// DeleteObject
-		bucket.Methods(http.MethodDelete).Path("/{object:.+}").HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.DeleteObjectHandler, ACTION_WRITE)), "DELETE"))
+		bucket.Methods(http.MethodDelete).Path(BucketPathTpl).HandlerFunc(track(s3a.iam.Auth(s3a.cb.Limit(s3a.DeleteObjectHandler, ACTION_WRITE)), "DELETE"))
 
 		// raw objects