1 // Copyright (c) 2012 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.
5 #ifndef EXTENSIONS_BROWSER_API_DECLARATIVE_RULES_REGISTRY_H__
6 #define EXTENSIONS_BROWSER_API_DECLARATIVE_RULES_REGISTRY_H__
13 #include "base/callback_forward.h"
14 #include "base/compiler_specific.h"
15 #include "base/gtest_prod_util.h"
16 #include "base/memory/scoped_ptr.h"
17 #include "base/memory/weak_ptr.h"
18 #include "content/public/browser/browser_thread.h"
19 #include "content/public/browser/notification_observer.h"
20 #include "content/public/browser/notification_registrar.h"
21 #include "extensions/common/api/events.h"
22 #include "extensions/common/one_shot_event.h"
32 namespace extensions {
34 class RulesCacheDelegate;
36 // A base class for RulesRegistries that takes care of storing the
37 // RulesRegistry::Rule objects. It contains all the methods that need to run on
38 // the registry thread; methods that need to run on the UI thread are separated
39 // in the RulesCacheDelegate object.
40 class RulesRegistry : public base::RefCountedThreadSafe<RulesRegistry> {
42 typedef extensions::core_api::events::Rule Rule;
44 int embedder_process_id;
45 int webview_instance_id;
46 WebViewKey(int embedder_process_id, int webview_instance_id)
47 : embedder_process_id(embedder_process_id),
48 webview_instance_id(webview_instance_id) {}
49 bool operator<(const WebViewKey& other) const {
50 return embedder_process_id < other.embedder_process_id ||
51 ((embedder_process_id == other.embedder_process_id) &&
52 (webview_instance_id < other.webview_instance_id));
56 enum Defaults { DEFAULT_PRIORITY = 100 };
57 // After the RulesCacheDelegate object (the part of the registry which runs on
58 // the UI thread) is created, a pointer to it is passed to |*ui_part|.
59 // In tests, |browser_context| and |ui_part| can be NULL (at the same time).
60 // In that case the storage functionality disabled (no RulesCacheDelegate
62 RulesRegistry(content::BrowserContext* browser_context,
63 const std::string& event_name,
64 content::BrowserThread::ID owner_thread,
65 RulesCacheDelegate* cache_delegate,
66 const WebViewKey& webview_key);
68 const OneShotEvent& ready() const {
72 // RulesRegistry implementation:
74 // Registers |rules|, owned by |extension_id| to this RulesRegistry.
75 // If a concrete RuleRegistry does not support some of the rules,
76 // it may ignore them.
78 // |rules| is a list of Rule instances following the definition of the
79 // declarative extension APIs. It is guaranteed that each rule in |rules| has
80 // a unique name within the scope of |extension_id| that has not been
81 // registered before, unless it has been removed again.
82 // The ownership of rules remains with the caller.
84 // Returns an empty string if the function is successful or an error
87 // IMPORTANT: This function is atomic. Either all rules that are deemed
88 // relevant are added or none.
90 const std::string& extension_id,
91 const std::vector<linked_ptr<RulesRegistry::Rule> >& rules);
93 // Unregisters all rules listed in |rule_identifiers| and owned by
94 // |extension_id| from this RulesRegistry.
95 // Some or all IDs in |rule_identifiers| may not be stored in this
96 // RulesRegistry and are ignored.
98 // Returns an empty string if the function is successful or an error
101 // IMPORTANT: This function is atomic. Either all rules that are deemed
102 // relevant are removed or none.
103 std::string RemoveRules(
104 const std::string& extension_id,
105 const std::vector<std::string>& rule_identifiers);
107 // Same as RemoveAllRules but acts on all rules owned by |extension_id|.
108 std::string RemoveAllRules(const std::string& extension_id);
110 // Returns all rules listed in |rule_identifiers| and owned by |extension_id|
111 // registered in this RuleRegistry. Entries in |rule_identifiers| that
112 // are unknown are ignored.
114 // The returned rules are stored in |out|. Ownership is passed to the caller.
115 void GetRules(const std::string& extension_id,
116 const std::vector<std::string>& rule_identifiers,
117 std::vector<linked_ptr<RulesRegistry::Rule> >* out);
119 // Same as GetRules but returns all rules owned by |extension_id|.
120 void GetAllRules(const std::string& extension_id,
121 std::vector<linked_ptr<RulesRegistry::Rule> >* out);
123 // Called to notify the RulesRegistry that the extension availability has
124 // changed, so that the registry can update which rules are active.
125 void OnExtensionUnloaded(const std::string& extension_id);
126 void OnExtensionUninstalled(const std::string& extension_id);
127 void OnExtensionLoaded(const std::string& extension_id);
129 // Returns the number of entries in used_rule_identifiers_ for leak detection.
130 // Every ExtensionId counts as one entry, even if it contains no rules.
131 size_t GetNumberOfUsedRuleIdentifiersForTesting() const;
133 // Returns the RulesCacheDelegate. This is used for testing.
134 RulesCacheDelegate* rules_cache_delegate_for_testing() const {
135 return cache_delegate_.get();
138 // Returns the context where the rules registry lives.
139 content::BrowserContext* browser_context() { return browser_context_; }
141 // Returns the ID of the thread on which the rules registry lives.
142 // It is safe to call this function from any thread.
143 content::BrowserThread::ID owner_thread() const { return owner_thread_; }
145 // The name of the event with which rules are registered.
146 const std::string& event_name() const { return event_name_; }
148 // The key that identifies the webview (or tabs) in which these rules apply.
149 // If the rules apply to the main browser, then this returns the tuple (0, 0).
150 const WebViewKey& webview_key() const {
155 virtual ~RulesRegistry();
157 // The precondition for calling this method is that all rules have unique IDs.
158 // AddRules establishes this precondition and calls into this method.
159 // Stored rules already meet this precondition and so they avoid calling
160 // CheckAndFillInOptionalRules for improved performance.
162 // Returns an empty string if the function is successful or an error
163 // message otherwise.
164 std::string AddRulesNoFill(
165 const std::string& extension_id,
166 const std::vector<linked_ptr<RulesRegistry::Rule> >& rules);
168 // These functions need to apply the rules to the browser, while the base
169 // class will handle defaulting empty fields before calling *Impl, and will
170 // automatically cache the rules and re-call *Impl on browser startup.
171 virtual std::string AddRulesImpl(
172 const std::string& extension_id,
173 const std::vector<linked_ptr<RulesRegistry::Rule> >& rules) = 0;
174 virtual std::string RemoveRulesImpl(
175 const std::string& extension_id,
176 const std::vector<std::string>& rule_identifiers) = 0;
177 virtual std::string RemoveAllRulesImpl(
178 const std::string& extension_id) = 0;
181 friend class base::RefCountedThreadSafe<RulesRegistry>;
182 friend class RulesCacheDelegate;
184 typedef std::string ExtensionId;
185 typedef std::string RuleId;
186 typedef std::pair<ExtensionId, RuleId> RulesDictionaryKey;
187 typedef std::map<RulesDictionaryKey, linked_ptr<RulesRegistry::Rule> >
189 enum ProcessChangedRulesState {
190 // ProcessChangedRules can never be called, |cache_delegate_| is NULL.
192 // A task to call ProcessChangedRules is scheduled for future execution.
193 SCHEDULED_FOR_PROCESSING,
194 // No task to call ProcessChangedRules is scheduled yet, but it is possible
196 NOT_SCHEDULED_FOR_PROCESSING
198 typedef std::map<ExtensionId, ProcessChangedRulesState> ProcessStateMap;
200 base::WeakPtr<RulesRegistry> GetWeakPtr() {
201 DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
202 return weak_ptr_factory_.GetWeakPtr();
205 // Common processing after extension's rules have changed.
206 void ProcessChangedRules(const std::string& extension_id);
208 // Calls ProcessChangedRules if
209 // |process_changed_rules_requested_(extension_id)| ==
210 // NOT_SCHEDULED_FOR_PROCESSING.
211 void MaybeProcessChangedRules(const std::string& extension_id);
213 // This method implements the functionality of RemoveAllRules, except for not
214 // calling MaybeProcessChangedRules. That way updating the rules store and
215 // extension prefs is avoided. This method is called when an extension is
216 // uninstalled, that way there is no clash with the preferences being wiped.
217 std::string RemoveAllRulesNoStoreUpdate(const std::string& extension_id);
219 void MarkReady(base::Time storage_init_time);
221 // Deserialize the rules from the given Value object and add them to the
223 void DeserializeAndAddRules(const std::string& extension_id,
224 scoped_ptr<base::Value> rules);
226 // The context to which this rules registry belongs.
227 content::BrowserContext* browser_context_;
229 // The ID of the thread on which the rules registry lives.
230 const content::BrowserThread::ID owner_thread_;
232 // The name of the event with which rules are registered.
233 const std::string event_name_;
235 // The key that identifies the context in which these rules apply.
236 WebViewKey webview_key_;
238 RulesDictionary rules_;
240 // Signaled when we have finished reading from storage for all extensions that
241 // are loaded on startup.
244 // The factory needs to be declared before |cache_delegate_|, so that it can
245 // produce a pointer as a construction argument for |cache_delegate_|.
246 base::WeakPtrFactory<RulesRegistry> weak_ptr_factory_;
248 // |cache_delegate_| is owned by the registry service. If |cache_delegate_| is
249 // NULL, then the storage functionality is disabled (this is used in tests).
250 // This registry cannot own |cache_delegate_| because during the time after
251 // rules registry service shuts down on UI thread, and the registry is
252 // destroyed on its thread, the use of the |cache_delegate_| would not be
253 // safe. The registry only ever associates with one RulesCacheDelegate
255 base::WeakPtr<RulesCacheDelegate> cache_delegate_;
257 ProcessStateMap process_changed_rules_requested_;
259 // Returns whether any existing rule is registered with identifier |rule_id|
260 // for extension |extension_id|.
261 bool IsUniqueId(const std::string& extension_id,
262 const std::string& rule_id) const;
264 // Creates an ID that is unique within the scope of|extension_id|.
265 std::string GenerateUniqueId(const std::string& extension_id);
267 // Verifies that all |rules| have unique IDs or initializes them with
268 // unique IDs if they don't have one. In case of duplicate IDs, this function
269 // returns a non-empty error message.
270 std::string CheckAndFillInOptionalRules(
271 const std::string& extension_id,
272 const std::vector<linked_ptr<RulesRegistry::Rule> >& rules);
274 // Initializes the priority fields in case they have not been set.
275 void FillInOptionalPriorities(
276 const std::vector<linked_ptr<RulesRegistry::Rule> >& rules);
278 // Removes all |identifiers| of |extension_id| from |used_rule_identifiers_|.
279 void RemoveUsedRuleIdentifiers(const std::string& extension_id,
280 const std::vector<std::string>& identifiers);
282 // Same as RemoveUsedRuleIdentifiers but operates on all rules of
284 void RemoveAllUsedRuleIdentifiers(const std::string& extension_id);
286 typedef std::string RuleIdentifier;
287 typedef std::map<ExtensionId, std::set<RuleIdentifier> > RuleIdentifiersMap;
288 RuleIdentifiersMap used_rule_identifiers_;
289 int last_generated_rule_identifier_id_;
291 DISALLOW_COPY_AND_ASSIGN(RulesRegistry);
294 } // namespace extensions
296 #endif // EXTENSIONS_BROWSER_API_DECLARATIVE_RULES_REGISTRY_H__