chrome/browser/apps/ephemeral_app_service.cc

   1 // Copyright 2013 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 #include "chrome/browser/apps/ephemeral_app_service.h"
   6
   7 #include "base/command_line.h"
   8 #include "chrome/browser/apps/ephemeral_app_service_factory.h"
   9 #include "chrome/browser/chrome_notification_types.h"
  10 #include "chrome/browser/extensions/data_deleter.h"
  11 #include "chrome/browser/extensions/extension_service.h"
  12 #include "chrome/browser/extensions/extension_util.h"
  13 #include "chrome/browser/profiles/profile.h"
  14 #include "chrome/common/chrome_switches.h"
  15 #include "content/public/browser/notification_service.h"
  16 #include "content/public/browser/notification_source.h"
  17 #include "content/public/browser/notification_types.h"
  18 #include "extensions/browser/extension_prefs.h"
  19 #include "extensions/browser/extension_registry.h"
  20 #include "extensions/browser/extension_system.h"
  21 #include "extensions/browser/extension_util.h"
  22 #include "extensions/common/extension.h"
  23 #include "extensions/common/extension_set.h"
  24
  25 using extensions::Extension;
  26 using extensions::ExtensionInfo;
  27 using extensions::ExtensionPrefs;
  28 using extensions::ExtensionSet;
  29 using extensions::ExtensionSystem;
  30 using extensions::InstalledExtensionInfo;
  31
  32 namespace {
  33
  34 // The number of seconds after startup before performing garbage collection
  35 // of ephemeral apps.
  36 const int kGarbageCollectAppsStartupDelay = 60;
  37
  38 // The number of seconds after an ephemeral app has been installed before
  39 // performing garbage collection.
  40 const int kGarbageCollectAppsInstallDelay = 15;
  41
  42 // When the number of ephemeral apps reaches this count, trigger garbage
  43 // collection to trim off the least-recently used apps in excess of
  44 // kMaxEphemeralAppsCount.
  45 const int kGarbageCollectAppsTriggerCount = 35;
  46
  47 // The number of seconds after startup before performing garbage collection
  48 // of the data of evicted ephemeral apps.
  49 const int kGarbageCollectDataStartupDelay = 120;
  50
  51 }  // namespace
  52
  53 const int EphemeralAppService::kAppInactiveThreshold = 10;
  54 const int EphemeralAppService::kAppKeepThreshold = 1;
  55 const int EphemeralAppService::kMaxEphemeralAppsCount = 30;
  56 const int EphemeralAppService::kDataInactiveThreshold = 90;
  57
  58 // static
  59 EphemeralAppService* EphemeralAppService::Get(Profile* profile) {
  60   return EphemeralAppServiceFactory::GetForProfile(profile);
  61 }
  62
  63 EphemeralAppService::EphemeralAppService(Profile* profile)
  64     : profile_(profile),
  65       extension_registry_observer_(this),
  66       ephemeral_app_count_(-1) {
  67   if (!CommandLine::ForCurrentProcess()->HasSwitch(
  68             switches::kEnableEphemeralApps))
  69     return;
  70
  71   extension_registry_observer_.Add(
  72       extensions::ExtensionRegistry::Get(profile_));
  73   registrar_.Add(this, chrome::NOTIFICATION_EXTENSIONS_READY,
  74                  content::Source<Profile>(profile_));
  75   registrar_.Add(this, chrome::NOTIFICATION_PROFILE_DESTROYED,
  76                  content::Source<Profile>(profile_));
  77 }
  78
  79 EphemeralAppService::~EphemeralAppService() {
  80 }
  81
  82 void EphemeralAppService::Observe(
  83     int type,
  84     const content::NotificationSource& source,
  85     const content::NotificationDetails& details) {
  86   switch (type) {
  87     case chrome::NOTIFICATION_EXTENSIONS_READY: {
  88       Init();
  89       break;
  90     }
  91     case chrome::NOTIFICATION_PROFILE_DESTROYED: {
  92       // Ideally we need to know when the extension system is shutting down.
  93       garbage_collect_apps_timer_.Stop();
  94       break;
  95     }
  96     default:
  97       NOTREACHED();
  98   }
  99 }
 100
 101 void EphemeralAppService::OnExtensionWillBeInstalled(
 102     content::BrowserContext* browser_context,
 103     const extensions::Extension* extension,
 104     bool is_update,
 105     bool from_ephemeral,
 106     const std::string& old_name) {
 107   if (from_ephemeral) {
 108     // An ephemeral app was just promoted to a regular installed app.
 109     --ephemeral_app_count_;
 110     DCHECK_GE(ephemeral_app_count_, 0);
 111   } else if (!is_update &&
 112              extensions::util::IsEphemeralApp(extension->id(), profile_)) {
 113     ++ephemeral_app_count_;
 114     if (ephemeral_app_count_ >= kGarbageCollectAppsTriggerCount) {
 115       TriggerGarbageCollect(
 116           base::TimeDelta::FromSeconds(kGarbageCollectAppsInstallDelay));
 117     }
 118   }
 119 }
 120
 121 void EphemeralAppService::OnExtensionUninstalled(
 122     content::BrowserContext* browser_context,
 123     const extensions::Extension* extension) {
 124   if (extensions::util::IsEphemeralApp(extension->id(), profile_)) {
 125     --ephemeral_app_count_;
 126     DCHECK_GE(ephemeral_app_count_, 0);
 127   }
 128 }
 129
 130 void EphemeralAppService::Init() {
 131   InitEphemeralAppCount();
 132   TriggerGarbageCollect(
 133       base::TimeDelta::FromSeconds(kGarbageCollectAppsStartupDelay));
 134
 135   garbage_collect_data_timer_.Start(
 136       FROM_HERE,
 137       base::TimeDelta::FromSeconds(kGarbageCollectDataStartupDelay),
 138       this,
 139       &EphemeralAppService::GarbageCollectData);
 140 }
 141
 142 void EphemeralAppService::InitEphemeralAppCount() {
 143   scoped_ptr<ExtensionSet> extensions =
 144       extensions::ExtensionRegistry::Get(profile_)
 145           ->GenerateInstalledExtensionsSet();
 146   ExtensionPrefs* prefs = ExtensionPrefs::Get(profile_);
 147   DCHECK(prefs);
 148
 149   ephemeral_app_count_ = 0;
 150   for (ExtensionSet::const_iterator it = extensions->begin();
 151        it != extensions->end(); ++it) {
 152     const Extension* extension = *it;
 153     if (prefs->IsEphemeralApp(extension->id()))
 154       ++ephemeral_app_count_;
 155   }
 156 }
 157
 158 void EphemeralAppService::TriggerGarbageCollect(const base::TimeDelta& delay) {
 159   if (!garbage_collect_apps_timer_.IsRunning()) {
 160     garbage_collect_apps_timer_.Start(
 161         FROM_HERE,
 162         delay,
 163         this,
 164         &EphemeralAppService::GarbageCollectApps);
 165   }
 166 }
 167
 168 void EphemeralAppService::GarbageCollectApps() {
 169   scoped_ptr<ExtensionSet> extensions =
 170       extensions::ExtensionRegistry::Get(profile_)
 171           ->GenerateInstalledExtensionsSet();
 172   ExtensionPrefs* prefs = ExtensionPrefs::Get(profile_);
 173   DCHECK(prefs);
 174
 175   int app_count = 0;
 176   LaunchTimeAppMap app_launch_times;
 177   std::set<std::string> remove_app_ids;
 178
 179   // Populate a list of ephemeral apps, ordered by their last launch time.
 180   for (ExtensionSet::const_iterator it = extensions->begin();
 181        it != extensions->end(); ++it) {
 182     const Extension* extension = *it;
 183     if (!prefs->IsEphemeralApp(extension->id()))
 184       continue;
 185
 186     ++app_count;
 187
 188     // Do not remove ephemeral apps that are running.
 189     if (!extensions::util::IsExtensionIdle(extension->id(), profile_))
 190       continue;
 191
 192     base::Time last_launch_time = prefs->GetLastLaunchTime(extension->id());
 193
 194     // If the last launch time is invalid, this may be because it was just
 195     // installed. So use the install time. If this is also null for some reason,
 196     // the app will be removed.
 197     if (last_launch_time.is_null())
 198       last_launch_time = prefs->GetInstallTime(extension->id());
 199
 200     app_launch_times.insert(std::make_pair(last_launch_time, extension->id()));
 201   }
 202
 203   ExtensionService* service =
 204       ExtensionSystem::Get(profile_)->extension_service();
 205   DCHECK(service);
 206   // Execute the replacement policies and remove apps marked for deletion.
 207   if (!app_launch_times.empty()) {
 208     GetAppsToRemove(app_count, app_launch_times, &remove_app_ids);
 209     for (std::set<std::string>::const_iterator id = remove_app_ids.begin();
 210          id != remove_app_ids.end(); ++id) {
 211       if (service->UninstallExtension(*id, false, NULL))
 212         --app_count;
 213     }
 214   }
 215
 216   ephemeral_app_count_ = app_count;
 217 }
 218
 219 // static
 220 void EphemeralAppService::GetAppsToRemove(
 221     int app_count,
 222     const LaunchTimeAppMap& app_launch_times,
 223     std::set<std::string>* remove_app_ids) {
 224   base::Time time_now = base::Time::Now();
 225   const base::Time inactive_threshold =
 226       time_now - base::TimeDelta::FromDays(kAppInactiveThreshold);
 227   const base::Time keep_threshold =
 228       time_now - base::TimeDelta::FromDays(kAppKeepThreshold);
 229
 230   // Visit the apps in order of least recently to most recently launched.
 231   for (LaunchTimeAppMap::const_iterator it = app_launch_times.begin();
 232        it != app_launch_times.end(); ++it) {
 233     // Cannot remove apps that have been launched recently. So break when we
 234     // reach the new apps.
 235     if (it->first > keep_threshold)
 236         break;
 237
 238     // Remove ephemeral apps that have been inactive for a while or if the cache
 239     // is larger than the desired size.
 240     if (it->first < inactive_threshold || app_count > kMaxEphemeralAppsCount) {
 241       remove_app_ids->insert(it->second);
 242       --app_count;
 243     } else {
 244       break;
 245     }
 246   }
 247 }
 248
 249 void EphemeralAppService::GarbageCollectData() {
 250   ExtensionService* service =
 251       ExtensionSystem::Get(profile_)->extension_service();
 252   DCHECK(service);
 253   ExtensionPrefs* prefs = ExtensionPrefs::Get(profile_);
 254   DCHECK(prefs);
 255   scoped_ptr<ExtensionPrefs::ExtensionsInfo> evicted_apps_info(
 256       prefs->GetEvictedEphemeralAppsInfo());
 257
 258   base::Time time_now = base::Time::Now();
 259   const base::Time inactive_threshold =
 260       time_now - base::TimeDelta::FromDays(kDataInactiveThreshold);
 261
 262   for (size_t i = 0; i < evicted_apps_info->size(); ++i) {
 263     ExtensionInfo* info = evicted_apps_info->at(i).get();
 264     base::Time last_launch_time = prefs->GetLastLaunchTime(info->extension_id);
 265     if (last_launch_time > inactive_threshold)
 266       continue;
 267
 268     // Sanity check to ensure the app is not currently installed.
 269     if (service->GetInstalledExtension(info->extension_id)) {
 270       NOTREACHED();
 271       continue;
 272     }
 273
 274     // Ensure the app is not waiting to be installed.
 275     scoped_ptr<ExtensionInfo> delayed_install(
 276         prefs->GetDelayedInstallInfo(info->extension_id));
 277     if (delayed_install.get())
 278       continue;
 279
 280     if (info->extension_manifest.get()) {
 281       std::string error;
 282       scoped_refptr<const Extension> extension(Extension::Create(
 283           info->extension_path,
 284           info->extension_location,
 285           *info->extension_manifest,
 286           prefs->GetCreationFlags(info->extension_id),
 287           info->extension_id,
 288           &error));
 289
 290       if (extension.get())
 291         extensions::DataDeleter::StartDeleting(profile_, extension.get());
 292     }
 293
 294     prefs->RemoveEvictedEphemeralApp(info->extension_id);
 295   }
 296 }