Check the format to determine if link headers should be added, allow disabling on-the-fly generation

Author: indykoning

src/Middleware/AddHttp3EarlyHints.php

@@ -25,7 +25,7 @@ public function handle(Request $request, Closure $next, ?int $sizeLimit = null):
     {
         $lastPath = Str::afterLast($request->path(), '/');
         if (
-            $request->isJson()
+            $request->format() !== 'html'
             || (str_contains($lastPath, '.') && ! in_array(Str::afterLast($lastPath, '.'), config('http3earlyhints.extensions', ['', 'php', 'html'])))
         ) {
             $this->skipCurrentRequest = true;
@@ -38,6 +38,9 @@ public function handle(Request $request, Closure $next, ?int $sizeLimit = null):
         $linkHeaders = Cache::store(config('http3earlyhints.cache_driver'))->get('earlyhints-'.md5($request->url()));
         if (! $linkHeaders) {
             $response = $next($request);
+            if (! config('http3earlyhints.generate_during_request', true)) {
+                return $response;
+            }
             $linkHeaders = $this->handleGeneratingLinkHeaders($request, $response);
             if ($linkHeaders) {
                 $this->addLinkHeaders($response, $linkHeaders);

src/config.php

@@ -7,6 +7,11 @@
      */
     'cache_duration' => env('EARLY_HINTS_CACHE_DURATION', 864000 /* 24h */),
     'cache_driver' => env('EARLY_HINTS_CACHE_DRIVER', null),
+    /**
+     * We always crawl the response after the response has been sent.
+     * If we do not have it in cache, should we crawl during the request to always send link headers?
+     */
+    'generate_during_request' => env('EARLY_HINTS_GENERATE_DURING_REQUEST', true),
     /** Wether to send the 103. This means we do not need an external party to handle early hints but is currently only supported by FrankenPHP */
     'send_103' => env('EARLY_HINTS_SEND_103', false) && \function_exists('headers_send'),
     /** Size limit in bytes */