[subresource_filter] SB throttle can send multiple speculative requests.

components/subresource_filter/content/browser/subresource_filter_safe_browsing_client_request.h

+// Copyright 2017 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.
+
+#ifndef COMPONENTS_SUBRESOURCE_FILTER_CONTENT_BROWSER_SUBRESOURCE_FILTER_SAFE_BROWSING_CLIENT_REQUEST_H_
+#define COMPONENTS_SUBRESOURCE_FILTER_CONTENT_BROWSER_SUBRESOURCE_FILTER_SAFE_BROWSING_CLIENT_REQUEST_H_
+
+#include <stddef.h>
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/time/time.h"
+#include "base/timer/timer.h"
+#include "components/safe_browsing_db/database_manager.h"
+#include "components/safe_browsing_db/util.h"
+#include "components/safe_browsing_db/v4_local_database_manager.h"
+#include "url/gurl.h"
+
+namespace base {
+class SingleThreadTaskRunner;
+}  // namespace base
+
+namespace safe_browsing {
+struct ThreatMetadata;
+}  // namespace safe_browsing
+
+namespace subresource_filter {
+
+class SubresourceFilterSafeBrowsingClient;
+
+// This class is scoped to a single database check, and it lives on the IO
+// thread exclusively.
+class SubresourceFilterSafeBrowsingClientRequest
+    : public safe_browsing::SafeBrowsingDatabaseManager::Client {
+ public:
+  SubresourceFilterSafeBrowsingClientRequest(
+      const GURL& url,
+      size_t request_id,
+      scoped_refptr<safe_browsing::SafeBrowsingDatabaseManager>
+          database_manager,
+      scoped_refptr<base::SingleThreadTaskRunner> io_task_runner,
+      SubresourceFilterSafeBrowsingClient* client);
+  ~SubresourceFilterSafeBrowsingClientRequest() override;
+
+  void Start();
+
+  // safe_browsing::SafeBrowsingDatabaseManager::Client:
+  void OnCheckBrowseUrlResult(
+      const GURL& url,
+      safe_browsing::SBThreatType threat_type,
+      const safe_browsing::ThreatMetadata& metadata) override;
+
+  const GURL& url() const { return url_; }
+  size_t request_id() const { return request_id_; }
+
+  // Maximum time in milliseconds to wait for the Safe Browsing service to
+  // verify a URL. After this amount of time the outstanding check will be
+  // aborted, and the URL will be treated as if it didn't belong to the
+  // Subresource Filter only list.
+  static constexpr base::TimeDelta kCheckURLTimeout =
+      base::TimeDelta::FromSeconds(5);
+
+ private:
+  // Callback for when the safe browsing check has taken longer than
+  // kCheckURLTimeout.
+  void OnCheckUrlTimeout();
+
+  void SendCheckResultToClient(bool served_from_network,
+                               safe_browsing::SBThreatType threat_type,
+                               const safe_browsing::ThreatMetadata& metadata);
+
+  const GURL url_;
+
+  // The |request_id_| identifies a particular request, as issued from the
+  // SubresourceFilterSafeBrowsingClient. It will be unique in the scope of a
+  // single navigation (i.e. the scope of the
+  // SubresourceFilterSafeBrowsingClient).
+  const size_t request_id_;
+
+  scoped_refptr<safe_browsing::SafeBrowsingDatabaseManager> database_manager_;
+  SubresourceFilterSafeBrowsingClient* client_ = nullptr;
+
+  // Timer to abort the safe browsing check if it takes too long.
+  base::OneShotTimer timer_;
+
+  base::TimeTicks start_time_;
+
+  bool request_completed_ = false;
+
+  DISALLOW_COPY_AND_ASSIGN(SubresourceFilterSafeBrowsingClientRequest);
+};
+
+}  // namespace subresource_filter
+
+#endif  // COMPONENTS_SUBRESOURCE_FILTER_CONTENT_BROWSER_SUBRESOURCE_FILTER_SAFE_BROWSING_CLIENT_REQUEST_H_