use etags

index.ts

@@ -68,6 +68,9 @@ async function getTBAEndpoint(endpoint: string): Promise<TBAResponse> {
 
   console.log("Fetching... " + endpoint);
   const headers = new Headers(authHeaders);
+  if (tbaCache[endpoint]) {
+    headers.append("If-None-Match", tbaCache[endpoint].etag);
+  }
   const response = await fetch(BASE_URL + endpoint, { headers });
 
   let data;