Support the Clear-Site-Data header on resource requests

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 <string>
 #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 "base/time/time.h"
 #include "content/public/browser/resource_request_info.h"
+#include "content/public/browser/resource_throttle.h"
 #include "content/public/common/console_message_level.h"
+#include "net/http/http_response_headers.h"
 #include "url/gurl.h"
 
+namespace net {
+class HttpResponseHeaders;
+struct RedirectInfo;
+class URLRequest;
+}
+
+namespace url {
+class Origin;
+}
+
 namespace content {
 
-class NavigationHandle;
+// This throttle parses the Clear-Site-Data header and executes the clearing
+// of browsing data. The resource load is delayed until the header is parsed
+// and, if valid, until the browsing data are deleted. See the W3C working draft
+// at https://w3c.github.io/webappsec-clear-site-data/.
+class CONTENT_EXPORT ClearSiteDataThrottle : public ResourceThrottle {
+ public:
+  // Stores and outputs console messages.
+  class CONTENT_EXPORT ConsoleMessagesDelegate {
+   public:
+    struct Message {
+      GURL url;
+      std::string text;
+      ConsoleMessageLevel level;
+    };
 
-// 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;
+    ConsoleMessagesDelegate();
+    virtual ~ConsoleMessagesDelegate();
+
+    // Logs a |text| message from |url| with |level|.
+    virtual void AddMessage(const GURL& url,
+                            const std::string& text,
+                            ConsoleMessageLevel level);
+
+    // Outputs stored messages to the console of WebContents identified by
+    // |web_contents_getter|.
+    virtual void OutputMessages(
+        const ResourceRequestInfo::WebContentsGetter& web_contents_getter);
+
+    const std::vector<Message>& messages() const { return messages_; }
+
+   private:
+    std::vector<Message> messages_;
   };
 
-  static std::unique_ptr<NavigationThrottle> CreateThrottleForNavigation(
-      NavigationHandle* handle);
+  // Instantiates a throttle for the given |request|. The caller must
+  // guarantee that |request| outlives the throttle.
+  static std::unique_ptr<ResourceThrottle> CreateThrottleForRequest(

[mmenke, 2017/05/22 19:36:08]

MaybeCreateThrottleForRequest?

[msramek, 2017/05/24 22:59:52]

Done.

+      net::URLRequest* request);
 
   ~ClearSiteDataThrottle() override;
 
-  // NavigationThrottle implementation:
-  ThrottleCheckResult WillStartRequest() override;
-  ThrottleCheckResult WillRedirectRequest() override;
-  ThrottleCheckResult WillProcessResponse() override;
-  const char* GetNameForLogging() override;
-
- private:
-  friend class ClearSiteDataFuzzerTest;
-  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();
+  // ResourceThrottle implementation:
+  const char* GetNameForLogging() const override;
+  void WillRedirectRequest(const net::RedirectInfo& redirect_info,
+                           bool* defer) override;
+  void WillProcessResponse(bool* defer) override;
 
   // 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);
+  // The |delegate| will be filled with messages to be output in the console,
+  // prepended by the |current_url|. Returns true if parsing was successful.
+  static bool ParseHeader(const std::string& header,
+                          bool* clear_cookies,
+                          bool* clear_storage,
+                          bool* clear_cache,
+                          ConsoleMessagesDelegate* delegate,
+                          const GURL& current_url);

[mmenke, 2017/05/22 18:35:35]

I'd suggest making this a public *ForTest / ForTesting wrapper around a private
method, to make it clear this is only exposed for testing.

[msramek, 2017/05/24 22:59:52]

Done. (Although I'd say that since the method is static, misusing this method
can't bring the throttle to an invalid state or anything.)

+
+ protected:
+  ClearSiteDataThrottle(net::URLRequest* request,
+                        std::unique_ptr<ConsoleMessagesDelegate> delegate);
+
+  // Returns HTTP response headers of the underlying URLRequest.
+  // Can be overriden for testing.
+  virtual const net::HttpResponseHeaders* GetResponseHeaders() const;
+
+  // Executes the clearing task. Can be overriden for testing.
+  virtual void ExecuteClearingTask(const url::Origin& origin,
+                                   bool clear_cookies,
+                                   bool clear_storage,
+                                   bool clear_cache,
+                                   const base::Closure& callback);

[mmenke, 2017/05/22 18:35:35]

These can both be private (private virtual methods can be overridden by
subclasses, they just can't be invoked by them).

[msramek, 2017/05/24 22:59:52]

Done.

+
+ private:
+  // Scans for the first occurrence of the 'Clear-Site-Data' header, calls
+  // ParseHeader() to parse it, and then ExecuteClearingTask() if applicable.
+  // This is the common logic of WillRedirectRequest()
+  // and WillProcessResponse(). Returns true if a valid header was found and
+  // the clearing was executed.
+  bool HandleHeader();
 
   // 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_;
+  // The request this throttle is observing.
+  net::URLRequest* request_;
 
-  // Whether we are currently waiting for a callback that data clearing has
-  // been completed;
-  bool clearing_in_progress_;
+  // The delegate that stores and outputs console messages.
+  std::unique_ptr<ConsoleMessagesDelegate> delegate_;
 
   // The time when the last clearing operation started. Used when clearing
   // finishes to compute the duration.
   base::TimeTicks clearing_started_;
 
   // 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_