NotificationPromo

chrome/browser/web_resource/promo_notification.h

+// Copyright (c) 2011 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_WEB_RESOURCE_PROMO_NOTIFICATION_H_
+#define CHROME_BROWSER_WEB_RESOURCE_PROMO_NOTIFICATION_H_
+#pragma once

[Dan Beam, 2011/09/27 03:27:55]

Why are you using this ^, exactly?  Shouldn't a header guard be enough?  I've
heard there can be cross-platform issues with #pragma directives.  On further
research (http://goo.gl/4GMwE), I guess it's OK if you leave it here, but it
doesn't really do anything (and I don't see it in any other files) and in one
case GCC recommends not using it (but this was a really long time ago...,
http://goo.gl/wmXgo).

[achuithb, 2011/09/27 08:03:19]

You're supposed to use it:
http://dev.chromium.org/developers/coding-style#TOC-File-headers

+
+#include <string>
+
+#include "base/basictypes.h"
+#include "base/gtest_prod_util.h"
+
+namespace base {
+  class DictionaryValue;
+}
+
+class PrefService;
+
+// Helper class for PromoResourceService that parses promo notification info
+// from json or prefs.
+class PromoNotification {
+ public:
+  class Delegate {
+   public:
+     virtual ~Delegate() {}
+     virtual void OnNewNotification(double start, double end) = 0;
+     // For testing.
+     virtual bool IsBuildAllowed(int builds_targeted) const { return false; }
+  };
+
+  explicit PromoNotification(PrefService* prefs, Delegate* delegate);
+
+  // Initialize from json/prefs.
+  void InitFromJson(const base::DictionaryValue& json);
+  void InitFromPrefs();
+
+  // Can this promo be shown?
+  bool CanShow() const;
+
+  static void RegisterUserPrefs(PrefService* prefs);
+
+  // Calculates promo notification start time with group-based time slice
+  // offset.
+  double StartTimeWithOffset() const;
+
+ private:
+  // For testing.
+  friend class PromoNotificationTestDelegate;
+  FRIEND_TEST_ALL_PREFIXES(PromoResourceServiceTest, GetNextQuestionValueTest);
+  FRIEND_TEST_ALL_PREFIXES(PromoResourceServiceTest, NewGroupTest);
+
+  // Users are randomly assigned to one of kMaxGroupSize + 1 buckets, in order
+  // to be able to roll out promos slowly, or display different promos to
+  // different groups.
+  static const int kMaxGroupSize = 99;
+  static const int kMaxViews = 1000;

[Miranda Callahan, 2011/09/27 09:18:40]

Can you add a comment for kMaxViews as well?

+
+  // Parse the answers array element.
+  void Parse(const base::DictionaryValue* dict);
+
+  // Set promo notification params from a question string, which is of the form
+  // <build_type>:<time_slice>:<max_group>:<max_views>
+  void GetParams(const base::DictionaryValue* dict);
+
+  // Check if this promo notification is new based on start/end times,
+  // and trigger events accordingly.
+  void CheckForNewNotification();
+
+  // Actions on receiving a new promo notification.
+  void OnNewNotification();
+
+  // Create a new promo notification group.
+  static int NewGroup();
+
+  // Parses question string.
+  static int GetNextQuestionValue(const std::string& question,
+                                  size_t* index,
+                                  bool* err);
+
+  static bool OutOfBounds(int var, int min, int max);
+
+  // Time getters.
+  static double GetTimeFromDict(const base::DictionaryValue* dict);
+  static double GetTimeFromString(const std::string& time_str);
+  double GetTimeFromPrefs(const char* pref) const;

[Dan Beam, 2011/09/27 03:27:55]

Should these be returning Times or doubles?  I guess it doesn't matter that
much, but I just remember reading in the time class that's it's better to do
calculation on Time objects instead of on doubles.  Eh, I just re-looked at the
note in the code (http://goo.gl/jVmdg) and I guess we don't really care, so
whatevs...

[achuithb, 2011/09/27 08:03:19]

start_ and end_ are stored as doubles (because the underlying prefs are
doubles), so we convert everything to double. This is unchanged from the
PromoResourceService code.

+
+  // Flush data members to prefs for storage.
+  void WritePrefs();
+
+  // Match our channel with specified build type.
+  bool IsBuildAllowed(int builds_allowed) const;
+
+  // For testing.
+  bool operator==(const PromoNotification& other) const;
+
+  PrefService* prefs_;
+  Delegate* delegate_;
+
+  double start_;
+  double end_;
+
+  int build_;
+  int time_slice_;
+  int max_group_;
+  int max_views_;
+
+  int group_;
+  int views_;
+  std::string text_;
+  bool closed_;
+
+  DISALLOW_COPY_AND_ASSIGN(PromoNotification);
+};
+
+#endif  // CHROME_BROWSER_WEB_RESOURCE_PROMO_NOTIFICATION_H_
+