Core Rule Set: Nextcloud's calendar and contacts sync pass (closes #280)

rproxy passes MKCALENDAR on. nextcloud.conf allows it on
/remote.php/dav/calendars/ and PROPFIND on /.well-known/caldav and
carddav. The XML of an MKCOL there skips 930120, 932120, 932250 and
932260; that of an MKCALENDAR also 932125 and 932230, for its
description. A PUT of text/calendar or text/vcard there skips 920530:
the Calendar and Contacts apps name the charset twice when they change
an event or a contact.

Recorded from Nextcloud 35.0.2 with Calendar 6.6.5, Contacts 8.9.5 and
requests imitating DAVx5.

Model: opus-5-5

internal/rproxy/question_test.go

@@ -331,7 +331,7 @@ func TestAQuestionCarriesItsBodyWhateverTheMethod(t *testing.T) {
 func TestAMethodNotPassedOnIsAnswered405(t *testing.T) {
 	t.Parallel()
 
-	for _, method := range []string{http.MethodTrace, "MKCALENDAR", "BREW"} {
+	for _, method := range []string{http.MethodTrace, "BREW"} {
 		t.Run(method, func(t *testing.T) {
 			t.Parallel()
 
@@ -344,7 +344,8 @@ func TestAMethodNotPassedOnIsAnswered405(t *testing.T) {
 			got := visit(t, newRequest(t, method, addr, "/", http.NoBody))
 			if got.status != http.StatusMethodNotAllowed ||
 				got.header.Get("Allow") != "GET, HEAD, POST, OPTIONS, PUT, DELETE, PATCH, QUERY, "+
-					"PROPFIND, PROPPATCH, MKCOL, COPY, MOVE, REPORT, SEARCH, LOCK, UNLOCK" {
+					"PROPFIND, PROPPATCH, MKCOL, COPY, MOVE, REPORT, SEARCH, LOCK, UNLOCK, "+
+					"MKCALENDAR" {
 				t.Errorf("answered %+v, want 405 naming the methods passed on", got)
 			}
 
@@ -370,7 +371,7 @@ func TestEachMethodPassedOnReachesDiscriminatorAndTheApp(t *testing.T) {
 		http.MethodGet, http.MethodHead, http.MethodPost, http.MethodOptions,
 		http.MethodPut, http.MethodDelete, http.MethodPatch, "QUERY",
 		"PROPFIND", "PROPPATCH", "MKCOL", "COPY", "MOVE", "REPORT", "SEARCH",
-		"LOCK", "UNLOCK",
+		"LOCK", "UNLOCK", "MKCALENDAR",
 	} {
 		t.Run(method, func(t *testing.T) {
 			t.Parallel()

internal/rproxy/rproxy.go

@@ -53,7 +53,7 @@ const ownEndpointPrefix = "/_sww/"
 // them. It answers any other method 405 itself.
 // The WebDAV ones are for Nextcloud.
 const allowedMethods = "GET, HEAD, POST, OPTIONS, PUT, DELETE, PATCH, QUERY, " +
-	"PROPFIND, PROPPATCH, MKCOL, COPY, MOVE, REPORT, SEARCH, LOCK, UNLOCK"
+	"PROPFIND, PROPPATCH, MKCOL, COPY, MOVE, REPORT, SEARCH, LOCK, UNLOCK, MKCALENDAR"
 
 // Params are what New needs.
 type Params struct {