added next

src/main/java/de/jottyfan/bico/modules/CommonController.java

@@ -42,7 +42,20 @@ public abstract class CommonController {
 			return false;
 		}
 	}
-
+	
+	@ModelAttribute("hasDiakoneRole")
+	public Boolean hasDiakoneRole(Principal principal) {
+		OAuth2AuthenticationToken token = (OAuth2AuthenticationToken) principal;
+		if (token != null) {
+			OAuth2User user = token.getPrincipal();
+			@SuppressWarnings("unchecked")
+			List<String> roles = (List<String>) user.getAttributes().get("roles");
+			return roles.contains("Diakone");
+		} else {
+			LOGGER.warn("token is null, no roles can be detected");
+			return false;
+		}
+	}
 	/**
 	 * get the theme for the current session
 	 *