Refactor RulesRegistryWithCache to RulesRegistry

chrome/browser/extensions/api/declarative/rules_cache_delegate.cc

+// Copyright 2013 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.
+
+#include "chrome/browser/extensions/api/declarative/rules_cache_delegate.h"
+
+#include "chrome/browser/chrome_notification_types.h"
+#include "chrome/browser/extensions/api/declarative/rules_registry.h"
+#include "chrome/browser/extensions/extension_info_map.h"
+#include "chrome/browser/extensions/extension_service.h"
+#include "chrome/browser/extensions/extension_system.h"
+#include "chrome/browser/extensions/extension_util.h"
+#include "chrome/browser/extensions/state_store.h"
+#include "chrome/browser/profiles/profile.h"
+#include "content/public/browser/notification_details.h"
+#include "content/public/browser/notification_source.h"
+
+namespace {
+
+// Returns the key to use for storing declarative rules in the state store.
+std::string GetDeclarativeRuleStorageKey(const std::string& event_name,
+                                         bool incognito) {
+  if (incognito)
+    return "declarative_rules.incognito." + event_name;
+  else
+    return "declarative_rules." + event_name;
+}
+
+}  // namespace
+
+namespace extensions {
+
+// RulesCacheDelegate
+
+const char RulesCacheDelegate::kRulesStoredKey[] =
+    "has_declarative_rules";
+
+RulesCacheDelegate::RulesCacheDelegate(
+    Profile* profile,
+    const std::string& event_name,
+    content::BrowserThread::ID rules_registry_thread,
+    base::WeakPtr<RulesRegistry> registry,
+    bool log_storage_init_delay)
+    : profile_(profile),
+      storage_key_(GetDeclarativeRuleStorageKey(event_name,
+                                                profile->IsOffTheRecord())),
+      rules_stored_key_(GetRulesStoredKey(event_name,
+                                          profile->IsOffTheRecord())),
+      log_storage_init_delay_(log_storage_init_delay),
+      registry_(registry),
+      rules_registry_thread_(rules_registry_thread),
+      notified_registry_(false),
+      weak_ptr_factory_(this) {}
+
+RulesCacheDelegate::~RulesCacheDelegate() {}
+
+// Returns the key to use for storing whether the rules have been stored.
+// static
+std::string RulesCacheDelegate::GetRulesStoredKey(const std::string& event_name,
+                                                  bool incognito) {
+  std::string result(kRulesStoredKey);
+  result += incognito ? ".incognito." : ".";
+  return result + event_name;
+}
+
+// This is called from the constructor of RulesRegistry, so it is
+// important that it both
+// 1. calls no (in particular virtual) methods of the rules registry, and
+// 2. does not create scoped_refptr holding the registry. (A short-lived
+// scoped_refptr might delete the rules registry before it is constructed.)
+void RulesCacheDelegate::Init() {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+
+  ExtensionSystem& system = *ExtensionSystem::Get(profile_);
+  extensions::StateStore* store = system.rules_store();
+  if (store)
+    store->RegisterKey(storage_key_);
+
+  registrar_.Add(this,
+                 chrome::NOTIFICATION_EXTENSION_LOADED,
+                 content::Source<Profile>(profile_->GetOriginalProfile()));
+
+  if (profile_->IsOffTheRecord())
+    log_storage_init_delay_ = false;
+
+  system.ready().Post(
+      FROM_HERE,
+      base::Bind(&RulesCacheDelegate::ReadRulesForInstalledExtensions,
+                 GetWeakPtr()));
+  system.ready().Post(FROM_HERE,
+                      base::Bind(&RulesCacheDelegate::CheckIfReady,
+                                 GetWeakPtr()));
+}
+
+void RulesCacheDelegate::WriteToStorage(const std::string& extension_id,
+                                     scoped_ptr<base::Value> value) {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+  if (!profile_)
+    return;
+
+  const base::ListValue* rules = NULL;
+  CHECK(value->GetAsList(&rules));
+  bool rules_stored_previously = GetDeclarativeRulesStored(extension_id);
+  bool store_rules = !rules->empty();
+  SetDeclarativeRulesStored(extension_id, store_rules);
+  if (!rules_stored_previously && !store_rules)
+    return;
+
+  StateStore* store = ExtensionSystem::Get(profile_)->rules_store();
+  if (store)
+    store->SetExtensionValue(extension_id, storage_key_, value.Pass());
+}
+
+void RulesCacheDelegate::Observe(
+    int type,
+    const content::NotificationSource& source,
+    const content::NotificationDetails& details) {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+  DCHECK(type == chrome::NOTIFICATION_EXTENSION_LOADED);
+
+  const extensions::Extension* extension =
+      content::Details<const extensions::Extension>(details).ptr();
+  // TODO(mpcomplete): This API check should generalize to any use of
+  // declarative rules, not just webRequest.
+  if (extension->HasAPIPermission(APIPermission::kDeclarativeContent) ||
+      extension->HasAPIPermission(APIPermission::kDeclarativeWebRequest)) {
+    ExtensionInfoMap* extension_info_map =
+        ExtensionSystem::Get(profile_)->info_map();
+    if (profile_->IsOffTheRecord() &&
+        !extension_info_map->IsIncognitoEnabled(extension->id())) {
+      // Ignore this extension.
+    } else {
+      ReadFromStorage(extension->id());
+    }
+  }
+}
+
+void RulesCacheDelegate::CheckIfReady() {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+  if (notified_registry_ || !waiting_for_extensions_.empty())
+    return;
+
+  content::BrowserThread::PostTask(
+      rules_registry_thread_,
+      FROM_HERE,
+      base::Bind(
+          &RulesRegistry::MarkReady, registry_, storage_init_time_));
+  notified_registry_ = true;
+}
+
+void RulesCacheDelegate::ReadRulesForInstalledExtensions() {
+  ExtensionSystem& system = *ExtensionSystem::Get(profile_);
+  ExtensionService* extension_service = system.extension_service();
+  DCHECK(extension_service);
+  // In an OTR profile, we start on top of a normal profile already, so the
+  // extension service should be ready.
+  DCHECK(!profile_->IsOffTheRecord() || extension_service->is_ready());
+  if (extension_service->is_ready()) {
+    const ExtensionSet* extensions = extension_service->extensions();
+    for (ExtensionSet::const_iterator i = extensions->begin();
+         i != extensions->end();
+         ++i) {
+      bool needs_apis_storing_rules =
+          (*i)->HasAPIPermission(APIPermission::kDeclarativeContent) ||
+          (*i)->HasAPIPermission(APIPermission::kDeclarativeWebRequest);
+      bool respects_off_the_record =
+          !(profile_->IsOffTheRecord()) ||
+          extension_util::IsIncognitoEnabled((*i)->id(), extension_service);
+      if (needs_apis_storing_rules && respects_off_the_record)
+        ReadFromStorage((*i)->id());
+    }
+  }
+}
+
+void RulesCacheDelegate::ReadFromStorage(const std::string& extension_id) {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+  if (!profile_)
+    return;
+
+  if (log_storage_init_delay_ && storage_init_time_.is_null())
+    storage_init_time_ = base::Time::Now();
+
+  if (!GetDeclarativeRulesStored(extension_id)) {
+    ExtensionSystem::Get(profile_)->ready().Post(
+        FROM_HERE, base::Bind(&RulesCacheDelegate::CheckIfReady, GetWeakPtr()));
+    return;
+  }
+
+  extensions::StateStore* store = ExtensionSystem::Get(profile_)->rules_store();
+  if (!store)
+    return;
+  waiting_for_extensions_.insert(extension_id);
+  store->GetExtensionValue(
+      extension_id,
+      storage_key_,
+      base::Bind(&RulesCacheDelegate::ReadFromStorageCallback,
+                 weak_ptr_factory_.GetWeakPtr(),
+                 extension_id));
+}
+
+void RulesCacheDelegate::ReadFromStorageCallback(
+    const std::string& extension_id,
+    scoped_ptr<base::Value> value) {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+  content::BrowserThread::PostTask(
+      rules_registry_thread_,
+      FROM_HERE,
+      base::Bind(&RulesRegistry::DeserializeAndAddRules,
+                 registry_,
+                 extension_id,
+                 base::Passed(&value)));
+
+  waiting_for_extensions_.erase(extension_id);
+
+  if (waiting_for_extensions_.empty())
+    ExtensionSystem::Get(profile_)->ready().Post(
+        FROM_HERE, base::Bind(&RulesCacheDelegate::CheckIfReady, GetWeakPtr()));
+}
+
+bool RulesCacheDelegate::GetDeclarativeRulesStored(
+    const std::string& extension_id) const {
+  CHECK(profile_);
+  const ExtensionScopedPrefs* extension_prefs = ExtensionPrefs::Get(profile_);
+
+  bool rules_stored = true;
+  if (extension_prefs->ReadPrefAsBoolean(
+          extension_id, rules_stored_key_, &rules_stored))
+    return rules_stored;
+
+  // Safe default -- if we don't know that the rules are not stored, we force
+  // a read by returning true.
+  return true;
+}
+
+void RulesCacheDelegate::SetDeclarativeRulesStored(
+    const std::string& extension_id,
+    bool rules_stored) {
+  CHECK(profile_);
+  ExtensionScopedPrefs* extension_prefs = ExtensionPrefs::Get(profile_);
+  extension_prefs->UpdateExtensionPref(
+      extension_id,
+      rules_stored_key_,
+      new base::FundamentalValue(rules_stored));
+}
+
+}  // namespace extensions