Service Worker: Change last update check location and HTTP cache bypass rule (2/2)

content/browser/service_worker/service_worker_dispatcher_host.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/service_worker/service_worker_dispatcher_host.h"
 
 #include "base/logging.h"
 #include "base/profiler/scoped_tracker.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/trace_event/trace_event.h"
@@ skipping 417 matching lines @@
   if (!registration->GetNewestVersion()) {
     // This can happen if update() is called during initial script evaluation.
     // Abort the following steps according to the spec.
     Send(new ServiceWorkerMsg_ServiceWorkerUpdateError(
         thread_id, request_id, WebServiceWorkerError::ErrorTypeState,
         base::ASCIIToUTF16(kServiceWorkerUpdateErrorPrefix) +
             base::ASCIIToUTF16(kInvalidStateErrorMessage)));
     return;
   }
 
-  // The spec says, "update() pings the server for an updated version of this
-  // script without consulting caches", so set |force_bypass_cache| to true.
+  // update() does not always bypass the browser cache. It obeys the same rule
+  // as other update attempts that bypasses the browser cache only when
+  // min(Cache-Control's max-age value, 86400) seconds have passed since the
+  // last update.

[nhiroki, 2015/08/24 07:57:51]

Probably this comment should be moved to service_worker_context_core.h and only
mention 86400 seconds (24-hours) update because the Cache-Control header is
actually handled in the lower network layer like a regular request and SW does
not have to take care of it.

For example, "Updates the service worker. If |force_bypass_cache| is true or
86400 seconds (24 hours) have passed since the last update, bypasses the browser
cache."

[jungkees, 2015/08/25 09:36:51]

Agreed. I'll move the suggested comment to service_worker_context_core.h.

   GetContext()->UpdateServiceWorker(
-      registration, true, /* force_bypass_cache */
+      registration, false, /* force_bypass_cache */
       provider_host, base::Bind(&ServiceWorkerDispatcherHost::UpdateComplete,
                                 this, thread_id, provider_id, request_id));
 }
 
 void ServiceWorkerDispatcherHost::OnUnregisterServiceWorker(
     int thread_id,
     int request_id,
     int provider_id,
     int64 registration_id) {
   TRACE_EVENT0("ServiceWorker",
@@ skipping 834 matching lines @@
   if (!handle) {
     bad_message::ReceivedBadMessage(this,
                                     bad_message::SWDH_TERMINATE_BAD_HANDLE);
     return;
   }
   handle->version()->StopWorker(
       base::Bind(&ServiceWorkerUtils::NoOpStatusCallback));
 }
 
 }  // namespace content