What causes "CalDAV: calendar object path is invalid" in siyuan-note/siyuan?

Append the .ics extension to the object file name in the URL before calling the API (ICalendarFileExt = ".ics").

CalDAV: calendar object path is invalid

Error message

CalDAV: calendar object path is invalid

What it means

ErrorCalDavCalendarObjectPathInvalid is returned by ParseCalendarObjectPath (kernel/model/caldav.go:110-113) when the file name portion of a calendar object URL does not end with the iCalendar extension '.ics'. The calendar path depth check passed, so the URL targets a calendar, but the last segment is not a well-formed object file name. GetObject/DeleteObject propagate it after path parsing fails.

Source

Thrown at kernel/model/caldav.go:85

		Path:                  CalDavDefaultCalendarPath,
		Name:                  CalDavDefaultCalendarName,
		Description:           "Default calendar",
		MaxResourceSize:       calendarMaxResourceSize,
		SupportedComponentSet: calendarSupportedComponentSet,
	}
	calendars = Calendars{
		loaded:            false,
		changed:           false,
		lock:              sync.Mutex{},
		calendars:         sync.Map{},
		calendarsMetaData: []*caldav.Calendar{},
	}

	ErrorCalDavCalendarNotFound    = errors.New("CalDAV: calendar not found")
	ErrorCalDavCalendarPathInvalid = errors.New("CalDAV: calendar path is invalid")

	ErrorCalDavCalendarObjectNotFound    = errors.New("CalDAV: calendar object not found")
	ErrorCalDavCalendarObjectPathInvalid = errors.New("CalDAV: calendar object path is invalid")
)

// CalendarsMetaDataFilePath returns the absolute path of the calendars' meta data file
func CalendarsMetaDataFilePath() string {
	return DavPath2DirectoryPath(CalDavCalendarsMetaDataFilePath)
}

func GetCalDavPathDepth(urlPath string) CalDavPathDepth {
	urlPath = PathCleanWithSlash(urlPath)
	return CalDavPathDepth(len(strings.Split(urlPath, "/")) - 1)
}

// GetCardDavPathDepth parses
func ParseCalendarObjectPath(objectPath string) (calendarPath string, objectID string, err error) {
	calendarPath, objectFileName := path.Split(objectPath)
	calendarPath = PathCleanWithSlash(calendarPath)
	objectID = path.Base(objectFileName)
	objectFileExt := util.Ext(objectFileName)

View on GitHub (pinned to 8641553a1f)

Solutions

Append the .ics extension to the object file name in the URL before calling the API (ICalendarFileExt = ".ics").
If the server generates the path, verify it returns URLs ending in .ics as declared by the calendar's resource list.
Check path building code for dropped extensions (e.g. using path.Base of an ID instead of id + ".ics").
Confirm the URL depth matches /caldav/principals/main/calendars/<calendar>/<object>.ics (6 segments).

Example fix

// before
objectPath := calPath + "/" + eventID
obj, err := ParseCalendarObjectPath(objectPath) // ErrorCalDavCalendarObjectPathInvalid

// after
objectPath := calPath + "/" + eventID + ".ics"
obj, err := ParseCalendarObjectPath(objectPath)

Defensive patterns

Strategy: validation

Validate before calling

if !strings.HasSuffix(objectPath, ".ics") {
    return fmt.Errorf("calendar object path must end with .ics: %s", objectPath)
}
if _, _, err := model.ParseCalendarObjectPath(objectPath); err != nil {
    return err
}

Type guard

func hasICalendarExt(objectPath string) bool {
    return path.Ext(objectPath) == ".ics"
}

Try / catch

if _, _, err := model.ParseCalendarObjectPath(p); err != nil {
    if errors.Is(err, model.ErrorCalDavCalendarObjectPathInvalid) {
        p = strings.TrimSuffix(p, path.Ext(p)) + ".ics" // normalize once
    }
}

Prevention

Build object paths with the ICalendarFileExt constant instead of hard-coded or omitted extensions.
Normalize client-supplied object URLs early: append .ics when the final segment has no extension.
Unit-test path builders to assert every generated URL parses via ParseCalendarObjectPath without error.
Keep object IDs extension-free internally and only add .ics when composing the URL.

When it happens

Trigger: ParseCalendarObjectPath is given a path whose final segment lacks the .ics extension (e.g. /caldav/principals/main/calendars/default/evt-1, .../evt-1.ical, or .../calendars.json), typically via Calendars.GetObject, Calendars.DeleteObject, or a CalDAV request handler routing an object URL.

Common situations: A client PUTs or requests an object without appending .ics (some hand-rolled CalDAV scripts do this); a plugin or integration builds the object URL by concatenation and forgets the extension; a directory listing URL is mistakenly treated as an object URL.

Understand the failure class

Background: "Invalid ... format", "must be in format X", "does not look like a ..." — invalid argument format errors across CLI tools and libraries — this error's family across 17 libraries.

Related errors

AI-assisted analysis of siyuan-note/siyuan@8641553a1f (2026-09-11). Data as JSON: /api/errors/603f683f48864094. Report an issue: GitHub.