ServiceWorker: Bypass SW when the script doesn't have fetch handler

content/browser/service_worker/service_worker_controllee_request_handler.cc

 // Copyright 2014 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_controllee_request_handler.h"
 
 #include <memory>
 #include <string>
 
 #include "base/trace_event/trace_event.h"
 #include "content/browser/service_worker/service_worker_context_core.h"
 #include "content/browser/service_worker/service_worker_metrics.h"
 #include "content/browser/service_worker/service_worker_provider_host.h"
 #include "content/browser/service_worker/service_worker_registration.h"
 #include "content/browser/service_worker/service_worker_response_info.h"
 #include "content/browser/service_worker/service_worker_url_request_job.h"
 #include "content/common/resource_request_body.h"
 #include "content/common/service_worker/service_worker_types.h"
 #include "content/common/service_worker/service_worker_utils.h"
 #include "content/public/browser/content_browser_client.h"
 #include "content/public/common/content_client.h"
 #include "content/public/common/resource_response_info.h"
 #include "net/base/load_flags.h"
 #include "net/base/url_util.h"
 #include "net/url_request/url_request.h"
 
 namespace content {
 
+namespace {
+
+void MaybeForwardToServiceWorker(ServiceWorkerURLRequestJob* job,
+                                 ServiceWorkerVersion* version) {
+  DCHECK(job);
+  DCHECK(version);
+  if (version->has_fetch_handler())
+    job->ForwardToServiceWorker();
+  else
+    job->FallbackToNetwork();
+}
+
+}  // namespace
+
 ServiceWorkerControlleeRequestHandler::ServiceWorkerControlleeRequestHandler(
     base::WeakPtr<ServiceWorkerContextCore> context,
     base::WeakPtr<ServiceWorkerProviderHost> provider_host,
     base::WeakPtr<storage::BlobStorageContext> blob_storage_context,
     FetchRequestMode request_mode,
     FetchCredentialsMode credentials_mode,
     FetchRedirectMode redirect_mode,
     ResourceType resource_type,
     RequestContextType request_context_type,
     RequestContextFrameType frame_type,
@@ skipping 205 matching lines @@
         "ServiceWorker",
         "ServiceWorkerControlleeRequestHandler::PrepareForMainResource",
         job_.get(),
         "Status", status,
         "Info",
         "ServiceWorkerVersion is not available, so falling back to network");
     return;
   }
 
   ServiceWorkerMetrics::CountControlledPageLoad(stripped_url_);
+  MaybeForwardToServiceWorker(job_.get(), active_version.get());
 
-  job_->ForwardToServiceWorker();
   TRACE_EVENT_ASYNC_END2(
       "ServiceWorker",
       "ServiceWorkerControlleeRequestHandler::PrepareForMainResource",
       job_.get(),
       "Status", status,
       "Info",
       "Forwarded to the ServiceWorker");

[falken, 2016/05/30 06:11:29]

nit: can you update this trace to say whether it was forwarded or skipped?

[shimazu, 2016/05/30 09:45:33]

Done.

 }
 
 void ServiceWorkerControlleeRequestHandler::OnVersionStatusChanged(
     ServiceWorkerRegistration* registration,
     ServiceWorkerVersion* version) {
   // The job may have been canceled and then destroyed before this was invoked.
   if (!job_)
     return;
 
   if (provider_host_)
     provider_host_->SetAllowAssociation(true);
   if (version != registration->active_version() ||
       version->status() != ServiceWorkerVersion::ACTIVATED ||
       !provider_host_) {
     job_->FallbackToNetwork();
     return;
   }
 
   ServiceWorkerMetrics::CountControlledPageLoad(stripped_url_);
 
   provider_host_->AssociateRegistration(registration,
                                         false /* notify_controllerchange */);
-  job_->ForwardToServiceWorker();
+
+  MaybeForwardToServiceWorker(job_.get(), version);
 }
 
 void ServiceWorkerControlleeRequestHandler::DidUpdateRegistration(
     const scoped_refptr<ServiceWorkerRegistration>& original_registration,
     ServiceWorkerStatusCode status,
     const std::string& status_message,
     int64_t registration_id) {
   DCHECK(force_update_started_);
 
   // The job may have been canceled and then destroyed before this was invoked.
@@ skipping 49 matching lines @@
   }
   version->RegisterStatusChangeCallback(
       base::Bind(&self::OnUpdatedVersionStatusChanged,
                  weak_factory_.GetWeakPtr(), registration, version));
 }
 
 void ServiceWorkerControlleeRequestHandler::PrepareForSubResource() {
   DCHECK(job_.get());
   DCHECK(context_);
   DCHECK(provider_host_->active_version());
-  job_->ForwardToServiceWorker();
+  MaybeForwardToServiceWorker(job_.get(), provider_host_->active_version());
 }
 
 void ServiceWorkerControlleeRequestHandler::OnPrepareToRestart() {
   use_network_ = true;
   ClearJob();
 }
 
 ServiceWorkerVersion*
 ServiceWorkerControlleeRequestHandler::GetServiceWorkerVersion(
     ServiceWorkerMetrics::URLRequestJobResult* result) {
@@ skipping 23 matching lines @@
   DCHECK(provider_host_);
   // Detach the controller so subresource requests also skip the worker.
   provider_host_->NotifyControllerLost();
 }
 
 void ServiceWorkerControlleeRequestHandler::ClearJob() {
   job_.reset();
 }
 
 }  // namespace content