feat: add string caching optimization to fetchf function and benchmark test

Author: MattCCC

src/request-handler.ts

@@ -63,6 +63,22 @@ export async function fetchf<
     RequestBody
   > | null = null,
 ): Promise<FetchResponse<ResponseData, RequestBody, QueryParams, PathParams>> {
+  // Ultra-fast early cache check if cacheKey is provided as a string
+  // For workloads dominated by repeated requests, this string caching optimization
+  // can potentially support millions of requests per second with minimal CPU overhead
+  if (reqConfig && typeof reqConfig.cacheKey === 'string') {
+    const cached = getCachedResponse<
+      ResponseData,
+      RequestBody,
+      QueryParams,
+      PathParams
+    >(reqConfig.cacheKey, reqConfig.cacheTime, reqConfig);
+
+    if (cached) {
+      return cached;
+    }
+  }
+
   const fetcherConfig = buildConfig<
     ResponseData,
     RequestBody,

test/benchmarks/fetchf.bench.mjs

@@ -37,6 +37,13 @@ const requestWithCache = () =>
     strategy: 'softFail',
   });
 
+const requestWithStringCache = () =>
+  fetchf('https://api.example.com/posts/1', {
+    cacheKey: 'post-1',
+    cacheTime: 300,
+    strategy: 'softFail',
+  });
+
 suite
   .add('Simple fetchf request', () => {
     return simpleRequest();
@@ -47,6 +54,9 @@ suite
   .add('fetchf with caching enabled', () => {
     return requestWithCache();
   })
+  .add('fetchf with string cache key', () => {
+    return requestWithStringCache();
+  })
   .on('cycle', (event) => {
     console.log(String(event.target));
   })