Implement delaying resource requests until privacy blacklists are ready.

chrome/browser/privacy_blacklist/blacklist_listener.cc

Index: chrome/browser/privacy_blacklist/blacklist_listener.cc
diff --git a/chrome/browser/privacy_blacklist/blacklist_listener.cc b/chrome/browser/privacy_blacklist/blacklist_listener.cc
new file mode 100644
index 0000000000000000000000000000000000000000..5e00236ededb86f62861cd8ab5d9946a0b660e34
--- /dev/null
+++ b/chrome/browser/privacy_blacklist/blacklist_listener.cc
@@ -0,0 +1,92 @@
+// Copyright (c) 2009 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 "chrome/browser/privacy_blacklist/blacklist_listener.h"
+
+#include "chrome/browser/chrome_thread.h"
+#include "chrome/browser/privacy_blacklist/blacklist.h"
+#include "chrome/browser/privacy_blacklist/blacklist_manager.h"
+#include "chrome/browser/privacy_blacklist/blacklist_request_info.h"
+#include "chrome/browser/profile.h"
+#include "chrome/browser/renderer_host/global_request_id.h"
+#include "chrome/common/notification_service.h"
+#include "chrome/common/notification_type.h"
+#include "net/url_request/url_request.h"
+
+BlacklistListener::BlacklistListener(ResourceQueue* resource_queue)
+    : resource_queue_(resource_queue) {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
+
+  registrar_.Add(this,
+                 NotificationType::BLACKLIST_MANAGER_ERROR,
+                 NotificationService::AllSources());
+  registrar_.Add(this,
+                 NotificationType::BLACKLIST_MANAGER_BLACKLIST_READ_FINISHED,
+                 NotificationService::AllSources());
+}
+
+BlacklistListener::~BlacklistListener() {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
+}
+
+void BlacklistListener::Observe(NotificationType type,
+                                const NotificationSource& source,
+                                const NotificationDetails& details) {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
+
+  switch (type.value) {
+    // TODO(phajdan.jr): Do not resume requests silently after an error.
+    case NotificationType::BLACKLIST_MANAGER_ERROR:
+    case NotificationType::BLACKLIST_MANAGER_BLACKLIST_READ_FINISHED:
+      {
+        Profile* profile = Source<Profile>(source).ptr();
+        ChromeThread::PostTask(ChromeThread::IO, FROM_HERE,
+            NewRunnableMethod(this, &BlacklistListener::StartDelayedRequests,
+                              profile->GetBlacklistManager()));
+      }
+      break;
+    default:
+      NOTREACHED();
+  }
+}
+
+bool BlacklistListener::ShouldDelayRequest(
+    URLRequest* request,
+    const ResourceDispatcherHostRequestInfo& request_info,
+    const GlobalRequestID& request_id) {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::IO));
+
+  BlacklistRequestInfo* blacklist_request_info =
+      BlacklistRequestInfo::FromURLRequest(request);
+  const BlacklistManager* blacklist_manager =
+      blacklist_request_info->GetBlacklistManager();
+
+  if (blacklist_manager->GetCompiledBlacklist()) {
+    // We have a blacklist ready. No need to delay the request.
+    return false;
+  }
+
+  delayed_requests_[blacklist_manager].push_back(request_id);
+  return true;
+}
+
+void BlacklistListener::WillShutdownResourceQueue() {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::IO));
+  resource_queue_ = NULL;
+}
+
+void BlacklistListener::StartDelayedRequests(
+    BlacklistManager* blacklist_manager) {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::IO));
+
+  if (resource_queue_) {
+    const RequestList& requests = delayed_requests_[blacklist_manager];
+    for (RequestList::const_iterator i = requests.begin();
+         i != requests.end(); ++i) {
+      resource_queue_->StartDelayedRequest(this, *i);
+    }
+  }
+
+  delayed_requests_[blacklist_manager].clear();
+}