// Copyright (c) 2012 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_EXTENSIONS_API_DECLARATIVE_RULES_REGISTRY_H__
#define CHROME_BROWSER_EXTENSIONS_API_DECLARATIVE_RULES_REGISTRY_H__
#include <map>
#include <set>
#include <string>
#include <vector>
#include "base/callback_forward.h"
#include "base/compiler_specific.h"
#include "base/gtest_prod_util.h"
#include "base/memory/scoped_ptr.h"
#include "base/memory/weak_ptr.h"
#include "chrome/common/extensions/api/events.h"
#include "content/public/browser/browser_thread.h"
#include "content/public/browser/notification_observer.h"
#include "content/public/browser/notification_registrar.h"
#include "extensions/common/one_shot_event.h"
class Profile;
namespace base {
class Value;
} // namespace base
namespace extensions {
class RulesCacheDelegate;
// A base class for RulesRegistries that takes care of storing the
// RulesRegistry::Rule objects. It contains all the methods that need to run on
// the registry thread; methods that need to run on the UI thread are separated
// in the RulesCacheDelegate object.
class RulesRegistry : public base::RefCountedThreadSafe<RulesRegistry> {
public:
typedef extensions::api::events::Rule Rule;
struct WebViewKey {
int embedder_process_id;
int webview_instance_id;
WebViewKey(int embedder_process_id, int webview_instance_id)
: embedder_process_id(embedder_process_id),
webview_instance_id(webview_instance_id) {}
bool operator<(const WebViewKey& other) const {
return embedder_process_id < other.embedder_process_id ||
((embedder_process_id == other.embedder_process_id) &&
(webview_instance_id < other.webview_instance_id));
}
};
enum Defaults { DEFAULT_PRIORITY = 100 };
// After the RulesCacheDelegate object (the part of the registry which runs on
// the UI thread) is created, a pointer to it is passed to |*ui_part|.
// In tests, |profile| and |ui_part| can be NULL (at the same time). In that
// case the storage functionality disabled (no RulesCacheDelegate object
// created).
RulesRegistry(Profile* profile,
const std::string& event_name,
content::BrowserThread::ID owner_thread,
RulesCacheDelegate* cache_delegate,
const WebViewKey& webview_key);
const OneShotEvent& ready() const {
return ready_;
}
// RulesRegistry implementation:
// Registers |rules|, owned by |extension_id| to this RulesRegistry.
// If a concrete RuleRegistry does not support some of the rules,
// it may ignore them.
//
// |rules| is a list of Rule instances following the definition of the
// declarative extension APIs. It is guaranteed that each rule in |rules| has
// a unique name within the scope of |extension_id| that has not been
// registered before, unless it has been removed again.
// The ownership of rules remains with the caller.
//
// Returns an empty string if the function is successful or an error
// message otherwise.
//
// IMPORTANT: This function is atomic. Either all rules that are deemed
// relevant are added or none.
std::string AddRules(
const std::string& extension_id,
const std::vector<linked_ptr<RulesRegistry::Rule> >& rules);
// Unregisters all rules listed in |rule_identifiers| and owned by
// |extension_id| from this RulesRegistry.
// Some or all IDs in |rule_identifiers| may not be stored in this
// RulesRegistry and are ignored.
//
// Returns an empty string if the function is successful or an error
// message otherwise.
//
// IMPORTANT: This function is atomic. Either all rules that are deemed
// relevant are removed or none.
std::string RemoveRules(
const std::string& extension_id,
const std::vector<std::string>& rule_identifiers);
// Same as RemoveAllRules but acts on all rules owned by |extension_id|.
std::string RemoveAllRules(const std::string& extension_id);
// Returns all rules listed in |rule_identifiers| and owned by |extension_id|
// registered in this RuleRegistry. Entries in |rule_identifiers| that
// are unknown are ignored.
//
// The returned rules are stored in |out|. Ownership is passed to the caller.
void GetRules(const std::string& extension_id,
const std::vector<std::string>& rule_identifiers,
std::vector<linked_ptr<RulesRegistry::Rule> >* out);
// Same as GetRules but returns all rules owned by |extension_id|.
void GetAllRules(const std::string& extension_id,
std::vector<linked_ptr<RulesRegistry::Rule> >* out);
// Called to notify the RulesRegistry that the extension availability has
// changed, so that the registry can update which rules are active.
void OnExtensionUnloaded(const std::string& extension_id);
void OnExtensionUninstalled(const std::string& extension_id);
void OnExtensionLoaded(const std::string& extension_id);
// Returns the number of entries in used_rule_identifiers_ for leak detection.
// Every ExtensionId counts as one entry, even if it contains no rules.
size_t GetNumberOfUsedRuleIdentifiersForTesting() const;
// Returns the RulesCacheDelegate. This is used for testing.
RulesCacheDelegate* rules_cache_delegate_for_testing() const {
return cache_delegate_.get();
}
// Returns the profile where the rules registry lives.
Profile* profile() const { return profile_; }
// Returns the ID of the thread on which the rules registry lives.
// It is safe to call this function from any thread.
content::BrowserThread::ID owner_thread() const { return owner_thread_; }
// The name of the event with which rules are registered.
const std::string& event_name() const { return event_name_; }
// The key that identifies the webview (or tabs) in which these rules apply.
// If the rules apply to the main browser, then this returns the tuple (0, 0).
const WebViewKey& webview_key() const {
return webview_key_;
}
protected:
virtual ~RulesRegistry();
// The precondition for calling this method is that all rules have unique IDs.
// AddRules establishes this precondition and calls into this method.
// Stored rules already meet this precondition and so they avoid calling
// CheckAndFillInOptionalRules for improved performance.
//
// Returns an empty string if the function is successful or an error
// message otherwise.
std::string AddRulesNoFill(
const std::string& extension_id,
const std::vector<linked_ptr<RulesRegistry::Rule> >& rules);
// These functions need to apply the rules to the browser, while the base
// class will handle defaulting empty fields before calling *Impl, and will
// automatically cache the rules and re-call *Impl on browser startup.
virtual std::string AddRulesImpl(
const std::string& extension_id,
const std::vector<linked_ptr<RulesRegistry::Rule> >& rules) = 0;
virtual std::string RemoveRulesImpl(
const std::string& extension_id,
const std::vector<std::string>& rule_identifiers) = 0;
virtual std::string RemoveAllRulesImpl(
const std::string& extension_id) = 0;
private:
friend class base::RefCountedThreadSafe<RulesRegistry>;
friend class RulesCacheDelegate;
typedef std::string ExtensionId;
typedef std::string RuleId;
typedef std::pair<ExtensionId, RuleId> RulesDictionaryKey;
typedef std::map<RulesDictionaryKey, linked_ptr<RulesRegistry::Rule> >
RulesDictionary;
enum ProcessChangedRulesState {
// ProcessChangedRules can never be called, |cache_delegate_| is NULL.
NEVER_PROCESS,
// A task to call ProcessChangedRules is scheduled for future execution.
SCHEDULED_FOR_PROCESSING,
// No task to call ProcessChangedRules is scheduled yet, but it is possible
// to schedule one.
NOT_SCHEDULED_FOR_PROCESSING
};
typedef std::map<ExtensionId, ProcessChangedRulesState> ProcessStateMap;
base::WeakPtr<RulesRegistry> GetWeakPtr() {
DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
return weak_ptr_factory_.GetWeakPtr();
}
// Common processing after extension's rules have changed.
void ProcessChangedRules(const std::string& extension_id);
// Calls ProcessChangedRules if
// |process_changed_rules_requested_(extension_id)| ==
// NOT_SCHEDULED_FOR_PROCESSING.
void MaybeProcessChangedRules(const std::string& extension_id);
// This method implements the functionality of RemoveAllRules, except for not
// calling MaybeProcessChangedRules. That way updating the rules store and
// extension prefs is avoided. This method is called when an extension is
// uninstalled, that way there is no clash with the preferences being wiped.
std::string RemoveAllRulesNoStoreUpdate(const std::string& extension_id);
void MarkReady(base::Time storage_init_time);
// Deserialize the rules from the given Value object and add them to the
// RulesRegistry.
void DeserializeAndAddRules(const std::string& extension_id,
scoped_ptr<base::Value> rules);
// The profile to which this rules registry belongs.
Profile* profile_;
// The ID of the thread on which the rules registry lives.
const content::BrowserThread::ID owner_thread_;
// The name of the event with which rules are registered.
const std::string event_name_;
// The key that identifies the context in which these rules apply.
WebViewKey webview_key_;
RulesDictionary rules_;
// Signaled when we have finished reading from storage for all extensions that
// are loaded on startup.
OneShotEvent ready_;
// The factory needs to be declared before |cache_delegate_|, so that it can
// produce a pointer as a construction argument for |cache_delegate_|.
base::WeakPtrFactory<RulesRegistry> weak_ptr_factory_;
// |cache_delegate_| is owned by the registry service. If |cache_delegate_| is
// NULL, then the storage functionality is disabled (this is used in tests).
// This registry cannot own |cache_delegate_| because during the time after
// rules registry service shuts down on UI thread, and the registry is
// destroyed on its thread, the use of the |cache_delegate_| would not be
// safe. The registry only ever associates with one RulesCacheDelegate
// instance.
base::WeakPtr<RulesCacheDelegate> cache_delegate_;
ProcessStateMap process_changed_rules_requested_;
// Returns whether any existing rule is registered with identifier |rule_id|
// for extension |extension_id|.
bool IsUniqueId(const std::string& extension_id,
const std::string& rule_id) const;
// Creates an ID that is unique within the scope of|extension_id|.
std::string GenerateUniqueId(const std::string& extension_id);
// Verifies that all |rules| have unique IDs or initializes them with
// unique IDs if they don't have one. In case of duplicate IDs, this function
// returns a non-empty error message.
std::string CheckAndFillInOptionalRules(
const std::string& extension_id,
const std::vector<linked_ptr<RulesRegistry::Rule> >& rules);
// Initializes the priority fields in case they have not been set.
void FillInOptionalPriorities(
const std::vector<linked_ptr<RulesRegistry::Rule> >& rules);
// Removes all |identifiers| of |extension_id| from |used_rule_identifiers_|.
void RemoveUsedRuleIdentifiers(const std::string& extension_id,
const std::vector<std::string>& identifiers);
// Same as RemoveUsedRuleIdentifiers but operates on all rules of
// |extension_id|.
void RemoveAllUsedRuleIdentifiers(const std::string& extension_id);
typedef std::string RuleIdentifier;
typedef std::map<ExtensionId, std::set<RuleIdentifier> > RuleIdentifiersMap;
RuleIdentifiersMap used_rule_identifiers_;
int last_generated_rule_identifier_id_;
DISALLOW_COPY_AND_ASSIGN(RulesRegistry);
};
} // namespace extensions
#endif // CHROME_BROWSER_EXTENSIONS_API_DECLARATIVE_RULES_REGISTRY_H__