Bug 1407276 - Avoid creating InterceptedHttpChannel if the service worker has no fetch event handler r=dom-workers-and-storage-reviewers,asuth

Differential Revision: https://phabricator.services.mozilla.com/D64092

--HG--
extra : moz-landing-system : lando

dom/serviceworkers/IPCServiceWorkerDescriptor.ipdlh

@@ -21,6 +21,7 @@ struct IPCServiceWorkerDescriptor
   nsCString scope;
   nsCString scriptURL;
   ServiceWorkerState state;
+  bool handlesFetch;
 };
 
 } // namespace dom

dom/serviceworkers/ServiceWorkerDescriptor.cpp

@@ -29,6 +29,8 @@ ServiceWorkerDescriptor::ServiceWorkerDescriptor(
   mData->scope() = aScope;
   mData->scriptURL() = aScriptURL;
   mData->state() = aState;
+  // Set HandlesFetch as true in default
+  mData->handlesFetch() = true;
 }
 
 ServiceWorkerDescriptor::ServiceWorkerDescriptor(
@@ -37,7 +39,7 @@ ServiceWorkerDescriptor::ServiceWorkerDescriptor(
     const nsACString& aScriptURL, ServiceWorkerState aState)
     : mData(MakeUnique<IPCServiceWorkerDescriptor>(
           aId, aRegistrationId, aRegistrationVersion, aPrincipalInfo,
-          nsCString(aScriptURL), nsCString(aScope), aState)) {}
+          nsCString(aScriptURL), nsCString(aScope), aState, true)) {}
 
 ServiceWorkerDescriptor::ServiceWorkerDescriptor(
     const IPCServiceWorkerDescriptor& aDescriptor)
@@ -118,6 +120,14 @@ void ServiceWorkerDescriptor::SetRegistrationVersion(uint64_t aVersion) {
   mData->registrationVersion() = aVersion;
 }
 
+bool ServiceWorkerDescriptor::HandlesFetch() const {
+  return mData->handlesFetch();
+}
+
+void ServiceWorkerDescriptor::SetHandlesFetch(bool aHandlesFetch) {
+  mData->handlesFetch() = aHandlesFetch;
+}
+
 bool ServiceWorkerDescriptor::Matches(
     const ServiceWorkerDescriptor& aDescriptor) const {
   return Id() == aDescriptor.Id() && Scope() == aDescriptor.Scope() &&

dom/serviceworkers/ServiceWorkerDescriptor.h

@@ -82,6 +82,10 @@ class ServiceWorkerDescriptor final {
 
   void SetRegistrationVersion(uint64_t aVersion);
 
+  bool HandlesFetch() const;
+
+  void SetHandlesFetch(bool aHandlesFetch);
+
   // Try to determine if two workers match each other.  This is less strict
   // than an operator==() call since it ignores mutable values like State().
   bool Matches(const ServiceWorkerDescriptor& aDescriptor) const;

dom/serviceworkers/ServiceWorkerInfo.h

@@ -126,6 +126,7 @@ class ServiceWorkerInfo final : public nsIServiceWorkerInfo {
     MOZ_ASSERT(NS_IsMainThread());
     MOZ_DIAGNOSTIC_ASSERT(mHandlesFetch == Unknown);
     mHandlesFetch = aHandlesFetch ? Enabled : Disabled;
+    mDescriptor.SetHandlesFetch(aHandlesFetch);
   }
 
   void SetRegistrationVersion(uint64_t aVersion);

dom/serviceworkers/ServiceWorkerInterceptController.cpp

@@ -32,7 +32,14 @@ ServiceWorkerInterceptController::ShouldPrepareForIntercept(
   if (!nsContentUtils::IsNonSubresourceRequest(aChannel)) {
     const Maybe<ServiceWorkerDescriptor>& controller =
         loadInfo->GetController();
-    *aShouldIntercept = controller.isSome();
+    // If the controller doesn't handle fetch events, return false
+    // TODO: https://w3c.github.io/ServiceWorker/#on-fetch-request-algorithm
+    //       17.2. May need to schedule a soft-update.
+    if (controller.isSome()) {
+      *aShouldIntercept = controller.ref().HandlesFetch();
+    } else {
+      *aShouldIntercept = false;
+    }
     return NS_OK;
   }
 
@@ -41,7 +48,7 @@ ServiceWorkerInterceptController::ShouldPrepareForIntercept(
 
   // First check with the ServiceWorkerManager for a matching service worker.
   RefPtr<ServiceWorkerManager> swm = ServiceWorkerManager::GetInstance();
-  if (!swm || !swm->IsAvailable(principal, aURI)) {
+  if (!swm || !swm->IsAvailable(principal, aURI, aChannel)) {
     return NS_OK;
   }
 

dom/serviceworkers/ServiceWorkerManager.cpp

@@ -2313,13 +2313,59 @@ void ServiceWorkerManager::DispatchFetchEvent(nsIInterceptedChannel* aChannel,
   aRv = uploadChannel->EnsureUploadStreamIsCloneable(permissionsRunnable);
 }
 
-bool ServiceWorkerManager::IsAvailable(nsIPrincipal* aPrincipal, nsIURI* aURI) {
+bool ServiceWorkerManager::IsAvailable(nsIPrincipal* aPrincipal, nsIURI* aURI,
+                                       nsIChannel* aChannel) {
   MOZ_ASSERT(aPrincipal);
   MOZ_ASSERT(aURI);
+  MOZ_ASSERT(aChannel);
 
   RefPtr<ServiceWorkerRegistrationInfo> registration =
       GetServiceWorkerRegistrationInfo(aPrincipal, aURI);
-  return registration && registration->GetActive();
+
+  // For child interception, just check the availability.
+  if (!ServiceWorkerParentInterceptEnabled()) {
+    return registration && registration->GetActive();
+  }
+
+  if (!registration || !registration->GetActive()) {
+    return false;
+  }
+
+  // Checking if the matched service worker handles fetch events or not.
+  // If it does, directly return true and handle the client controlling logic
+  // in DispatchFetchEvent(). otherwise, do followings then return false.
+  // 1. Set the matched service worker as the controller of LoadInfo and
+  //    correspoinding ClinetInfo
+  // 2. Maybe schedule a soft update
+  if (!registration->GetActive()->HandlesFetch()) {
+    // Checkin if the channel is not storage allowed first.
+    if (StorageAllowedForChannel(aChannel) != StorageAccess::eAllow) {
+      return false;
+    }
+
+    // ServiceWorkerInterceptController::ShouldPrepareForIntercept() handles the
+    // subresource cases. Must be non-subresource case here.
+    MOZ_ASSERT(nsContentUtils::IsNonSubresourceRequest(aChannel));
+
+    nsCOMPtr<nsILoadInfo> loadInfo = aChannel->LoadInfo();
+
+    Maybe<ClientInfo> clientInfo = loadInfo->GetReservedClientInfo();
+    if (clientInfo.isNothing()) {
+      clientInfo = loadInfo->GetInitialClientInfo();
+    }
+
+    if (clientInfo.isSome()) {
+      StartControllingClient(clientInfo.ref(), registration);
+    }
+    loadInfo->SetController(registration->GetActive()->Descriptor());
+
+    // https://w3c.github.io/ServiceWorker/#on-fetch-request-algorithm 17.1
+    // try schedule a soft-update for non-subresource case.
+    registration->MaybeScheduleTimeCheckAndUpdate();
+    return false;
+  }
+  // Found a matching service worker which handles fetch events, return true.
+  return true;
 }
 
 nsresult ServiceWorkerManager::GetClientRegistration(

dom/serviceworkers/ServiceWorkerManager.h

@@ -116,7 +116,14 @@ class ServiceWorkerManager final : public nsIServiceWorkerManager,
   NS_DECL_NSISERVICEWORKERMANAGER
   NS_DECL_NSIOBSERVER
 
-  bool IsAvailable(nsIPrincipal* aPrincipal, nsIURI* aURI);
+  // Return true if the given principal and URI matches a registered service
+  // worker which handles fetch event.
+  // If there is a matched service worker but doesn't handle fetch events, this
+  // method will try to set the matched service worker as the controller of the
+  // passed in channel. Then also schedule a soft-update job for the service
+  // worker.
+  bool IsAvailable(nsIPrincipal* aPrincipal, nsIURI* aURI,
+                   nsIChannel* aChannel);
 
   // Return true if the given content process could potentially be executing
   // service worker code with the given principal.  At the current time, this