enhance xml error response

internal/http/services/owncloud/ocdav/error.go

@@ -0,0 +1,50 @@
+// Copyright 2018-2020 CERN
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// In applying this license, CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+
+package ocdav
+
+import (
+	"encoding/xml"
+)
+
+type code int
+
+const (
+	SabredavMethodNotAllowed code = iota
+)
+
+var (
+	codesEnum = []string{
+		"Sabre\\DAV\\Exception\\MethodNotAllowed",
+	}
+)
+
+type exception struct {
+	code    code
+	message string
+}
+
+func Marshal(e exception) ([]byte, error) {
+
+	return xml.Marshal(&errorXML{
+		Xmlnsd:    "DAV",
+		Xmlnss:    "http://sabredav.org/ns",
+		Exception: codesEnum[e.code],
+		Message:   e.message,
+	})
+}

internal/http/services/owncloud/ocdav/propfind.go

@@ -61,6 +61,17 @@ func (s *svc) handlePropfind(w http.ResponseWriter, r *http.Request, ns string)
 	if r.URL.Path == "/" {
 		log.Debug().Str("path", r.URL.Path).Msg("method not allowed")
 		w.WriteHeader(http.StatusMethodNotAllowed)
+		b, err := Marshal(exception{
+			code:    SabredavMethodNotAllowed,
+			message: "Listing members of this collection is disabled",
+		})
+		if err != nil {
+			log.Error().Msgf("error marshaling xml response: %s", b)
+			w.WriteHeader(http.StatusInternalServerError)
+			return
+		}
+		w.Write(b)
+		return
 	}
 
 	// see https://tools.ietf.org/html/rfc4918#section-10.2
@@ -647,8 +658,12 @@ type propertyXML struct {
 
 // http://www.webdav.org/specs/rfc4918.html#ELEMENT_error
 type errorXML struct {
-	XMLName  xml.Name `xml:"d:error"`
-	InnerXML []byte   `xml:",innerxml"`
+	XMLName   xml.Name `xml:"d:error"`
+	Xmlnsd    string   `xml:"xmlns:d,attr"`
+	Xmlnss    string   `xml:"xmlns:s,attr"`
+	Exception string   `xml:"s:exception"`
+	Message   string   `xml:"s:message"`
+	InnerXML  []byte   `xml:",innerxml"`
 }
 
 var errInvalidPropfind = errors.New("webdav: invalid propfind")