First experimental implementation of the Clear-Site-Data header

content/browser/browsing_data/clear_site_data_throttle.h

+// Copyright 2016 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 CONTENT_BROWSER_BROWSING_DATA_CLEAR_SITE_DATA_THROTTLE_H_
+#define CONTENT_BROWSER_BROWSING_DATA_CLEAR_SITE_DATA_THROTTLE_H_
+
+#include <memory>
+#include <vector>
+
+#include "base/gtest_prod_util.h"
+#include "base/macros.h"
+#include "base/memory/weak_ptr.h"
+#include "base/values.h"
+#include "content/public/browser/navigation_throttle.h"
+#include "content/public/browser/resource_request_info.h"
+#include "content/public/common/console_message_level.h"
+#include "url/gurl.h"
+
+namespace content {
+
+class NavigationHandle;
+
+// This throttle parses the Clear-Site-Data header and executes the clearing
+// of browsing data. The navigation is delayed until the header is parsed and,
+// if valid, until the browsing data are deleted. See the W3C working draft at
+// https://www.w3.org/TR/clear-site-data/.
+class CONTENT_EXPORT ClearSiteDataThrottle : public NavigationThrottle {
+ public:
+  struct ConsoleMessage {
+    GURL url;
+    std::string text;
+    ConsoleMessageLevel level;
+  };
+
+  static std::unique_ptr<NavigationThrottle> CreateThrottleForNavigation(
+      NavigationHandle* handle);
+
+  ~ClearSiteDataThrottle() override;
+
+  // NavigationThrottle implementation:
+  ThrottleCheckResult WillStartRequest() override;
+  ThrottleCheckResult WillRedirectRequest() override;
+  ThrottleCheckResult WillProcessResponse() override;
+
+ private:
+  friend class ClearSiteDataThrottleTest;
+  FRIEND_TEST_ALL_PREFIXES(ClearSiteDataThrottleTest, ParseHeader);
+  FRIEND_TEST_ALL_PREFIXES(ClearSiteDataThrottleTest, InvalidHeader);
+
+  explicit ClearSiteDataThrottle(NavigationHandle* navigation_handle);
+
+  // Scans for the first occurrence of the 'Clear-Site-Data' header, calls
+  // ParseHeader() to parse it, and requests the actual data clearing. This is
+  // the common logic of WillRedirectRequest() and WillProcessResponse().
+  void HandleHeader();
+
+  // Parses the value of the 'Clear-Site-Data' header and outputs whether
+  // the header requests to |clear_cookies|, |clear_storage|, and |clear_cache|.
+  // The |messages| vector will be filled with messages to be output in the
+  // console. Returns true if parsing was successful.
+  bool ParseHeader(const std::string& header,
+                   bool* clear_cookies,
+                   bool* clear_storage,
+                   bool* clear_cache,
+                   std::vector<ConsoleMessage>* messages);
+
+  // Signals that a parsing and deletion task was finished.
+  void TaskFinished();
+
+  // Cached console messages to be output when the RenderFrameHost is ready.
+  std::vector<ConsoleMessage> messages_;
+  GURL current_url_;
+
+  // Whether we are currently waiting for a callback that data clearing has
+  // been completed;
+  bool clearing_in_progress_;
+
+  // Needed for asynchronous parsing and deletion tasks.
+  base::WeakPtrFactory<ClearSiteDataThrottle> weak_ptr_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(ClearSiteDataThrottle);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_BROWSING_DATA_CLEAR_SITE_DATA_THROTTLE_H_