change according to connection from frontend

src/helpers/typeTester.ts

@@ -0,0 +1,18 @@
+import { PlanTimeDefinition } from "../viewmodel/admin/unit/inspection/inspectionPlan.models";
+
+export default abstract class TypeTester {
+  static testPlanTimeDefinition(val: string, key: string = "", throwErr: boolean = false): PlanTimeDefinition | null {
+    if (/^(\d+-(d|m|y)|\d+\/(\d+|\*))$/.test(val)) {
+      return val as PlanTimeDefinition;
+    } else if (throwErr) {
+      throw Error(
+        [
+          key,
+          "provided String does not match PlanTimeDefinition Format: ${number}-${'d'|'m'|'y'} or ${number}/${number|'*'}",
+        ].join(": ")
+      );
+    } else {
+      return null;
+    }
+  }
+}