public static String getAppName(HttpServletRequest request) {
        String result = RequestContextHolder.getContext().getBasicContext().getApp();
        return isUnknownApp(result) ? request.getHeader(CLIENT_APPNAME_HEADER) : result;
    }
@Test
    void testGetAppNameFromContext() {
        RequestContextHolder.getContext().getBasicContext().setApp("contextApp");
        HttpServletRequest request = Mockito.mock(HttpServletRequest.class);
        Mockito.when(request.getHeader(eq(RequestUtil.CLIENT_APPNAME_HEADER))).thenReturn("test");
        assertEquals("contextApp", RequestUtil.getAppName(request));
    }