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 "apps/app_lifetime_monitor_factory.h"
   8 #include "base/command_line.h"
   9 #include "base/message_loop/message_loop.h"
  10 #include "chrome/browser/apps/ephemeral_app_service_factory.h"
  11 #include "chrome/browser/chrome_notification_types.h"
  12 #include "chrome/browser/extensions/extension_service.h"
  13 #include "chrome/browser/extensions/extension_util.h"
  14 #include "chrome/browser/profiles/profile.h"
  15 #include "chrome/common/chrome_switches.h"
  16 #include "content/public/browser/notification_service.h"
  17 #include "content/public/browser/notification_source.h"
  18 #include "content/public/browser/notification_types.h"
  19 #include "extensions/browser/extension_prefs.h"
  20 #include "extensions/browser/extension_registry.h"
  21 #include "extensions/browser/extension_system.h"
  22 #include "extensions/browser/extension_util.h"
  23 #include "extensions/browser/notification_types.h"
  24 #include "extensions/browser/uninstall_reason.h"
  25 #include "extensions/common/extension.h"
  26 #include "extensions/common/extension_set.h"
  27
  28 using extensions::Extension;
  29 using extensions::ExtensionPrefs;
  30 using extensions::ExtensionRegistry;
  31 using extensions::ExtensionSet;
  32 using extensions::ExtensionSystem;
  33
  34 namespace {
  35
  36 // The number of seconds after startup before performing garbage collection
  37 // of ephemeral apps.
  38 const int kGarbageCollectAppsStartupDelay = 60;
  39
  40 // The number of seconds after an ephemeral app has been installed before
  41 // performing garbage collection.
  42 const int kGarbageCollectAppsInstallDelay = 15;
  43
  44 // When the number of ephemeral apps reaches this count, trigger garbage
  45 // collection to trim off the least-recently used apps in excess of
  46 // kMaxEphemeralAppsCount.
  47 const int kGarbageCollectAppsTriggerCount = 35;
  48
  49 // The number of seconds after an app has stopped running before it will be
  50 // disabled.
  51 const int kDefaultDisableAppDelay = 1;
  52
  53 // The number of seconds after startup before disabling inactive ephemeral apps.
  54 const int kDisableAppsOnStartupDelay = 5;
  55
  56 }  // namespace
  57
  58 const int EphemeralAppService::kAppInactiveThreshold = 10;
  59 const int EphemeralAppService::kAppKeepThreshold = 1;
  60 const int EphemeralAppService::kMaxEphemeralAppsCount = 30;
  61
  62 // static
  63 EphemeralAppService* EphemeralAppService::Get(Profile* profile) {
  64   return EphemeralAppServiceFactory::GetForProfile(profile);
  65 }
  66
  67 EphemeralAppService::EphemeralAppService(Profile* profile)
  68     : profile_(profile),
  69       extension_registry_observer_(this),
  70       app_lifetime_monitor_observer_(this),
  71       ephemeral_app_count_(-1),
  72       disable_idle_app_delay_(kDefaultDisableAppDelay),
  73       weak_ptr_factory_(this) {
  74   registrar_.Add(this,
  75                  extensions::NOTIFICATION_EXTENSIONS_READY_DEPRECATED,
  76                  content::Source<Profile>(profile_));
  77 }
  78
  79 EphemeralAppService::~EphemeralAppService() {
  80 }
  81
  82 void EphemeralAppService::ClearCachedApps() {
  83   // Cancel any pending garbage collects.
  84   garbage_collect_apps_timer_.Stop();
  85
  86   ExtensionRegistry* registry = ExtensionRegistry::Get(profile_);
  87   DCHECK(registry);
  88   ExtensionPrefs* prefs = ExtensionPrefs::Get(profile_);
  89   DCHECK(prefs);
  90   ExtensionService* service =
  91       ExtensionSystem::Get(profile_)->extension_service();
  92   DCHECK(service);
  93
  94   scoped_ptr<ExtensionSet> extensions =
  95       registry->GenerateInstalledExtensionsSet();
  96
  97   for (ExtensionSet::const_iterator it = extensions->begin();
  98        it != extensions->end();
  99        ++it) {
 100     std::string extension_id = (*it)->id();
 101     if (!prefs->IsEphemeralApp(extension_id))
 102       continue;
 103
 104     // Do not remove apps that are running.
 105     if (!extensions::util::IsExtensionIdle(extension_id, profile_))
 106       continue;
 107
 108     DCHECK(registry->GetExtensionById(extension_id,
 109                                       ExtensionRegistry::EVERYTHING));
 110     service->UninstallExtension(
 111         extension_id,
 112         extensions::UNINSTALL_REASON_ORPHANED_EPHEMERAL_EXTENSION,
 113         base::Bind(&base::DoNothing),
 114         NULL);
 115   }
 116 }
 117
 118 void EphemeralAppService::Observe(
 119     int type,
 120     const content::NotificationSource& source,
 121     const content::NotificationDetails& details) {
 122   switch (type) {
 123     case extensions::NOTIFICATION_EXTENSIONS_READY_DEPRECATED: {
 124       Init();
 125       break;
 126     }
 127     default:
 128       NOTREACHED();
 129   }
 130 }
 131
 132 void EphemeralAppService::OnExtensionWillBeInstalled(
 133     content::BrowserContext* browser_context,
 134     const extensions::Extension* extension,
 135     bool is_update,
 136     bool from_ephemeral,
 137     const std::string& old_name) {
 138   if (from_ephemeral) {
 139     // An ephemeral app was just promoted to a regular installed app.
 140     --ephemeral_app_count_;
 141     DCHECK_GE(ephemeral_app_count_, 0);
 142     HandleEphemeralAppPromoted(extension);
 143   } else if (!is_update &&
 144              extensions::util::IsEphemeralApp(extension->id(), profile_)) {
 145     // A new ephemeral app was launched.
 146     ++ephemeral_app_count_;
 147     if (ephemeral_app_count_ >= kGarbageCollectAppsTriggerCount) {
 148       TriggerGarbageCollect(
 149           base::TimeDelta::FromSeconds(kGarbageCollectAppsInstallDelay));
 150     }
 151   }
 152 }
 153
 154 void EphemeralAppService::OnExtensionUninstalled(
 155     content::BrowserContext* browser_context,
 156     const extensions::Extension* extension,
 157     extensions::UninstallReason reason) {
 158   if (extensions::util::IsEphemeralApp(extension->id(), profile_)) {
 159     --ephemeral_app_count_;
 160     DCHECK_GE(ephemeral_app_count_, 0);
 161   }
 162 }
 163
 164 void EphemeralAppService::OnAppStop(Profile* profile,
 165                                     const std::string& app_id) {
 166   if (!extensions::util::IsEphemeralApp(app_id, profile_))
 167     return;
 168
 169   base::MessageLoop::current()->PostDelayedTask(
 170       FROM_HERE,
 171       base::Bind(&EphemeralAppService::DisableEphemeralApp,
 172                  weak_ptr_factory_.GetWeakPtr(),
 173                  app_id),
 174       base::TimeDelta::FromSeconds(disable_idle_app_delay_));
 175 }
 176
 177 void EphemeralAppService::OnChromeTerminating() {
 178   garbage_collect_apps_timer_.Stop();
 179
 180   extension_registry_observer_.RemoveAll();
 181   app_lifetime_monitor_observer_.RemoveAll();
 182 }
 183
 184 void EphemeralAppService::Init() {
 185   InitEphemeralAppCount();
 186
 187   // Start observing.
 188   extension_registry_observer_.Add(ExtensionRegistry::Get(profile_));
 189   app_lifetime_monitor_observer_.Add(
 190       apps::AppLifetimeMonitorFactory::GetForProfile(profile_));
 191
 192   // Execute startup clean up tasks (except during tests).
 193   if (base::CommandLine::ForCurrentProcess()->HasSwitch(switches::kTestType))
 194     return;
 195
 196   TriggerGarbageCollect(
 197       base::TimeDelta::FromSeconds(kGarbageCollectAppsStartupDelay));
 198
 199   base::MessageLoop::current()->PostDelayedTask(
 200       FROM_HERE,
 201       base::Bind(&EphemeralAppService::DisableEphemeralAppsOnStartup,
 202                  weak_ptr_factory_.GetWeakPtr()),
 203       base::TimeDelta::FromSeconds(kDisableAppsOnStartupDelay));
 204 }
 205
 206 void EphemeralAppService::InitEphemeralAppCount() {
 207   scoped_ptr<ExtensionSet> extensions =
 208       ExtensionRegistry::Get(profile_)->GenerateInstalledExtensionsSet();
 209   ExtensionPrefs* prefs = ExtensionPrefs::Get(profile_);
 210   DCHECK(prefs);
 211
 212   ephemeral_app_count_ = 0;
 213   for (ExtensionSet::const_iterator it = extensions->begin();
 214        it != extensions->end(); ++it) {
 215     const Extension* extension = it->get();
 216     if (prefs->IsEphemeralApp(extension->id()))
 217       ++ephemeral_app_count_;
 218   }
 219 }
 220
 221 void EphemeralAppService::DisableEphemeralApp(const std::string& app_id) {
 222   if (!extensions::util::IsEphemeralApp(app_id, profile_) ||
 223       !extensions::util::IsExtensionIdle(app_id, profile_)) {
 224     return;
 225   }
 226
 227   // After an ephemeral app has stopped running, unload it from extension
 228   // system and disable it to prevent all background activity.
 229   ExtensionService* service =
 230       ExtensionSystem::Get(profile_)->extension_service();
 231   DCHECK(service);
 232   service->DisableExtension(app_id, Extension::DISABLE_INACTIVE_EPHEMERAL_APP);
 233 }
 234
 235 void EphemeralAppService::DisableEphemeralAppsOnStartup() {
 236   ExtensionPrefs* prefs = ExtensionPrefs::Get(profile_);
 237   DCHECK(prefs);
 238   ExtensionService* service =
 239       ExtensionSystem::Get(profile_)->extension_service();
 240   DCHECK(service);
 241
 242   // Ensure that all inactive ephemeral apps are disabled to prevent all
 243   // background activity. This is done on startup to catch any apps that escaped
 244   // being disabled on shutdown.
 245   scoped_ptr<ExtensionSet> extensions =
 246       ExtensionRegistry::Get(profile_)->GenerateInstalledExtensionsSet();
 247   for (ExtensionSet::const_iterator it = extensions->begin();
 248        it != extensions->end();
 249        ++it) {
 250     const Extension* extension = it->get();
 251     if (!prefs->IsEphemeralApp(extension->id()))
 252       continue;
 253
 254     // Only V2 apps are installed ephemerally. Remove other ephemeral app types
 255     // that were cached before this policy was introduced.
 256     if (!extension->is_platform_app()) {
 257       service->UninstallExtension(
 258           extension->id(),
 259           extensions::UNINSTALL_REASON_ORPHANED_EPHEMERAL_EXTENSION,
 260           base::Bind(&base::DoNothing),
 261           NULL);
 262       continue;
 263     }
 264
 265     if (!prefs->HasDisableReason(extension->id(),
 266                                  Extension::DISABLE_INACTIVE_EPHEMERAL_APP) &&
 267         !prefs->IsExtensionRunning(extension->id()) &&
 268         extensions::util::IsExtensionIdle(extension->id(), profile_)) {
 269       service->DisableExtension(extension->id(),
 270                                 Extension::DISABLE_INACTIVE_EPHEMERAL_APP);
 271     }
 272   }
 273 }
 274
 275 void EphemeralAppService::HandleEphemeralAppPromoted(const Extension* app) {
 276   // When ephemeral apps are promoted to regular install apps, remove the
 277   // DISABLE_INACTIVE_EPHEMERAL_APP reason and enable the app if there are no
 278   // other reasons.
 279   ExtensionPrefs* prefs = ExtensionPrefs::Get(profile_);
 280   DCHECK(prefs);
 281
 282   int disable_reasons = prefs->GetDisableReasons(app->id());
 283   if (disable_reasons & Extension::DISABLE_INACTIVE_EPHEMERAL_APP) {
 284     prefs->RemoveDisableReason(app->id(),
 285                                Extension::DISABLE_INACTIVE_EPHEMERAL_APP);
 286     if (disable_reasons == Extension::DISABLE_INACTIVE_EPHEMERAL_APP)
 287       prefs->SetExtensionState(app->id(), Extension::ENABLED);
 288   }
 289 }
 290
 291 void EphemeralAppService::TriggerGarbageCollect(const base::TimeDelta& delay) {
 292   if (!garbage_collect_apps_timer_.IsRunning()) {
 293     garbage_collect_apps_timer_.Start(
 294         FROM_HERE,
 295         delay,
 296         this,
 297         &EphemeralAppService::GarbageCollectApps);
 298   }
 299 }
 300
 301 void EphemeralAppService::GarbageCollectApps() {
 302   ExtensionRegistry* registry = ExtensionRegistry::Get(profile_);
 303   DCHECK(registry);
 304   ExtensionPrefs* prefs = ExtensionPrefs::Get(profile_);
 305   DCHECK(prefs);
 306
 307   scoped_ptr<ExtensionSet> extensions =
 308       registry->GenerateInstalledExtensionsSet();
 309
 310   int app_count = 0;
 311   LaunchTimeAppMap app_launch_times;
 312   std::set<std::string> remove_app_ids;
 313
 314   // Populate a list of ephemeral apps, ordered by their last launch time.
 315   for (ExtensionSet::const_iterator it = extensions->begin();
 316        it != extensions->end(); ++it) {
 317     const Extension* extension = it->get();
 318     if (!prefs->IsEphemeralApp(extension->id()))
 319       continue;
 320
 321     ++app_count;
 322
 323     // Do not remove ephemeral apps that are running.
 324     if (!extensions::util::IsExtensionIdle(extension->id(), profile_))
 325       continue;
 326
 327     base::Time last_launch_time = prefs->GetLastLaunchTime(extension->id());
 328
 329     // If the last launch time is invalid, this may be because it was just
 330     // installed. So use the install time. If this is also null for some reason,
 331     // the app will be removed.
 332     if (last_launch_time.is_null())
 333       last_launch_time = prefs->GetInstallTime(extension->id());
 334
 335     app_launch_times.insert(std::make_pair(last_launch_time, extension->id()));
 336   }
 337
 338   ExtensionService* service =
 339       ExtensionSystem::Get(profile_)->extension_service();
 340   DCHECK(service);
 341   // Execute the eviction policies and remove apps marked for deletion.
 342   if (!app_launch_times.empty()) {
 343     GetAppsToRemove(app_count, app_launch_times, &remove_app_ids);
 344
 345     for (std::set<std::string>::const_iterator id = remove_app_ids.begin();
 346          id != remove_app_ids.end(); ++id) {
 347       // Protect against cascading uninstalls.
 348       if (!registry->GetExtensionById(*id, ExtensionRegistry::EVERYTHING))
 349         continue;
 350
 351       service->UninstallExtension(
 352           *id,
 353           extensions::UNINSTALL_REASON_ORPHANED_EPHEMERAL_EXTENSION,
 354           base::Bind(&base::DoNothing),
 355           NULL);
 356     }
 357   }
 358 }
 359
 360 // static
 361 void EphemeralAppService::GetAppsToRemove(
 362     int app_count,
 363     const LaunchTimeAppMap& app_launch_times,
 364     std::set<std::string>* remove_app_ids) {
 365   base::Time time_now = base::Time::Now();
 366   const base::Time inactive_threshold =
 367       time_now - base::TimeDelta::FromDays(kAppInactiveThreshold);
 368   const base::Time keep_threshold =
 369       time_now - base::TimeDelta::FromDays(kAppKeepThreshold);
 370
 371   // Visit the apps in order of least recently to most recently launched.
 372   for (LaunchTimeAppMap::const_iterator it = app_launch_times.begin();
 373        it != app_launch_times.end(); ++it) {
 374     // Cannot remove apps that have been launched recently. So break when we
 375     // reach the new apps.
 376     if (it->first > keep_threshold)
 377         break;
 378
 379     // Remove ephemeral apps that have been inactive for a while or if the cache
 380     // is larger than the desired size.
 381     if (it->first < inactive_threshold || app_count > kMaxEphemeralAppsCount) {
 382       remove_app_ids->insert(it->second);
 383       --app_count;
 384     } else {
 385       break;
 386     }
 387   }
 388 }