Cache feedback reports to disk in case of send failure.

chrome/browser/feedback/feedback_report.h

+// Copyright 2014 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 CHROME_BROWSER_FEEDBACK_FEEDBACK_REPORT_H_
+#define CHROME_BROWSER_FEEDBACK_FEEDBACK_REPORT_H_
+
+#include <string>
+
+#include "base/basictypes.h"
+#include "base/callback_forward.h"
+#include "base/files/file_path.h"
+#include "base/memory/ref_counted.h"
+#include "base/time/time.h"
+
+namespace base {
+class SequencedTaskRunner;
+}
+
+namespace content {
+class BrowserContext;
+}
+
+namespace feedback {
+
+typedef base::Callback<void(const std::string&)> QueueCallback;
+
+// This class holds a feedback report. Once a report is created, a disk backup
+// for it is created automatically. This backup needs to explicitly be
+// deleted by calling DeleteReportOnDisk.
+class FeedbackReport : public base::RefCounted<FeedbackReport> {
+ public:
+  FeedbackReport(content::BrowserContext* context,
+                 const base::Time& upload_at,
+                 const std::string& data);
+
+  // Stops the disk write of the report and deletes the report file if already
+  // written.
+  void DeleteReportOnDisk();
+
+  const base::Time& upload_at() const { return upload_at_; }
+  const std::string& data() const { return data_; }
+
+  // Loads the reports still on disk and queues then using the given callback.
+  // This call blocks on the file reads.
+  static void LoadReportsAndQueue(content::BrowserContext* context,
+                                  QueueCallback callback);
+
+ private:
+  friend class base::RefCounted<FeedbackReport>;
+  virtual ~FeedbackReport();
+
+  // Name of the file corresponding to this report.
+  base::FilePath file_;
+
+  base::FilePath reports_path_;
+  base::Time upload_at_;  // Upload this report at or after this time.
+  std::string data_;
+
+  scoped_refptr<base::SequencedTaskRunner> reports_task_runner_;
+
+  DISALLOW_COPY_AND_ASSIGN(FeedbackReport);
+};
+
+}  // namespace feedback
+
+#endif  // CHROME_BROWSER_FEEDBACK_FEEDBACK_REPORT_H_