1// Copyright 2014 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef COMPONENTS_KEYED_SERVICE_CONTENT_BROWSER_CONTEXT_KEYED_BASE_FACTORY_H_
6#define COMPONENTS_KEYED_SERVICE_CONTENT_BROWSER_CONTEXT_KEYED_BASE_FACTORY_H_
7
8#include <set>
9
10#include "base/threading/non_thread_safe.h"
11#include "components/keyed_service/core/dependency_node.h"
12#include "components/keyed_service/core/keyed_service_export.h"
13
14class BrowserContextDependencyManager;
15class PrefService;
16
17namespace content {
18class BrowserContext;
19}
20
21namespace user_prefs {
22class PrefRegistrySyncable;
23}
24
25// Base class for Factories that take a BrowserContext object and return some
26// service.
27//
28// Unless you're trying to make a new type of Factory, you probably don't want
29// this class, but its subclasses: BrowserContextKeyedServiceFactory and
30// RefcountedBrowserContextKeyedServiceFactory. This object describes general
31// dependency management between Factories; subclasses react to lifecycle
32// events and implement memory management.
33class KEYED_SERVICE_EXPORT BrowserContextKeyedBaseFactory
34    : public base::NonThreadSafe,
35      NON_EXPORTED_BASE(public DependencyNode) {
36 public:
37  // Registers preferences used in this service on the pref service of
38  // |context|. This is the public interface and is safe to be called multiple
39  // times because testing code can have multiple services of the same type
40  // attached to a single |context|. Only test code is allowed to call this
41  // method.
42  // TODO(gab): This method can be removed entirely when
43  // PrefService::DeprecatedGetPrefRegistry() is phased out.
44  void RegisterUserPrefsOnBrowserContextForTest(
45      content::BrowserContext* context);
46
47#ifndef NDEBUG
48  // Returns our name. We don't keep track of this in release mode.
49  const char* name() const { return service_name_; }
50#endif
51
52 protected:
53  BrowserContextKeyedBaseFactory(const char* name,
54                                 BrowserContextDependencyManager* manager);
55  virtual ~BrowserContextKeyedBaseFactory();
56
57  // The main public interface for declaring dependencies between services
58  // created by factories.
59  void DependsOn(BrowserContextKeyedBaseFactory* rhs);
60
61  // Calls RegisterProfilePrefs() after doing house keeping required to work
62  // alongside RegisterUserPrefsOnBrowserContextForTest().
63  // TODO(gab): This method can be replaced by RegisterProfilePrefs() directly
64  // once RegisterUserPrefsOnBrowserContextForTest() is phased out.
65  void RegisterProfilePrefsIfNecessaryForContext(
66      const content::BrowserContext* context,
67      user_prefs::PrefRegistrySyncable* registry);
68
69  // Interface for people building a concrete FooServiceFactory: --------------
70
71  // Finds which browser context (if any) to use.
72  virtual content::BrowserContext* GetBrowserContextToUse(
73      content::BrowserContext* context) const;
74
75  // By default, we create instances of a service lazily and wait until
76  // GetForBrowserContext() is called on our subclass. Some services need to be
77  // created as soon as the BrowserContext has been brought up.
78  virtual bool ServiceIsCreatedWithBrowserContext() const;
79
80  // By default, TestingBrowserContexts will be treated like normal contexts.
81  // You can override this so that by default, the service associated with the
82  // TestingBrowserContext is NULL. (This is just a shortcut around
83  // SetTestingFactory() to make sure our contexts don't directly refer to the
84  // services they use.)
85  virtual bool ServiceIsNULLWhileTesting() const;
86
87  // Interface for people building a type of BrowserContextKeyedFactory: -------
88
89  // A helper object actually listens for notifications about BrowserContext
90  // destruction, calculates the order in which things are destroyed and then
91  // does a two pass shutdown.
92  //
93  // It is up to the individual factory types to determine what this two pass
94  // shutdown means. The general framework guarantees the following:
95  //
96  // - Each BrowserContextShutdown() is called in dependency order (and you may
97  //   reach out to other services during this phase).
98  //
99  // - Each BrowserContextDestroyed() is called in dependency order. We will
100  //   NOTREACHED() if you attempt to GetForBrowserContext() any other service.
101  //   You should delete/deref/do other final memory management things during
102  //   this phase. You must also call the base class method as the last thing
103  //   you do.
104  virtual void BrowserContextShutdown(content::BrowserContext* context) = 0;
105  virtual void BrowserContextDestroyed(content::BrowserContext* context);
106
107  // Returns whether we've registered the preferences on this context.
108  bool ArePreferencesSetOn(content::BrowserContext* context) const;
109
110  // Mark context as Preferences set.
111  void MarkPreferencesSetOn(content::BrowserContext* context);
112
113  // Which BrowserContextDependencyManager we should communicate with.
114  // In real code, this will always be
115  // BrowserContextDependencyManager::GetInstance(), but unit tests will want
116  // to use their own copy.
117  BrowserContextDependencyManager* dependency_manager_;
118
119 private:
120  friend class BrowserContextDependencyManager;
121  friend class BrowserContextDependencyManagerUnittests;
122
123  // Registers any user preferences on this service. This is called by
124  // RegisterProfilePrefsIfNecessary() and should be overriden by any service
125  // that wants to register profile-specific preferences.
126  virtual void RegisterProfilePrefs(
127      user_prefs::PrefRegistrySyncable* registry) {}
128
129  // These two methods are for tight integration with the
130  // BrowserContextDependencyManager.
131
132  // Because of ServiceIsNULLWhileTesting(), we need a way to tell different
133  // subclasses that they should disable testing.
134  virtual void SetEmptyTestingFactory(content::BrowserContext* context) = 0;
135
136  // Returns true if a testing factory function has been set for |context|.
137  virtual bool HasTestingFactory(content::BrowserContext* context) = 0;
138
139  // We also need a generalized, non-returning method that generates the object
140  // now for when we're creating the context.
141  virtual void CreateServiceNow(content::BrowserContext* context) = 0;
142
143  // BrowserContexts that have this service's preferences registered on them.
144  std::set<const content::BrowserContext*> registered_preferences_;
145
146#if !defined(NDEBUG)
147  // A static string passed in to our constructor. Should be unique across all
148  // services. This is used only for debugging in debug mode. (We can print
149  // pretty graphs with GraphViz with this information.)
150  const char* service_name_;
151#endif
152};
153
154#endif  // COMPONENTS_KEYED_SERVICE_CONTENT_BROWSER_CONTEXT_KEYED_BASE_FACTORY_H_
155