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       ephemeral_app_count_(-1) {
  66   if (!CommandLine::ForCurrentProcess()->HasSwitch(
  67             switches::kEnableEphemeralApps))
  68     return;
  69
  70   registrar_.Add(this,
  71                  chrome::NOTIFICATION_EXTENSION_INSTALLED_DEPRECATED,
  72                  content::Source<Profile>(profile_));
  73   registrar_.Add(this, chrome::NOTIFICATION_EXTENSION_UNINSTALLED,
  74                  content::Source<Profile>(profile_));
  75   registrar_.Add(this, chrome::NOTIFICATION_EXTENSIONS_READY,
  76                  content::Source<Profile>(profile_));
  77   registrar_.Add(this, chrome::NOTIFICATION_PROFILE_DESTROYED,
  78                  content::Source<Profile>(profile_));
  79 }
  80
  81 EphemeralAppService::~EphemeralAppService() {
  82 }
  83
  84 void EphemeralAppService::Observe(
  85     int type,
  86     const content::NotificationSource& source,
  87     const content::NotificationDetails& details) {
  88   switch (type) {
  89     case chrome::NOTIFICATION_EXTENSIONS_READY: {
  90       Init();
  91       break;
  92     }
  93     case chrome::NOTIFICATION_EXTENSION_INSTALLED_DEPRECATED: {
  94       const Extension* extension =
  95           content::Details<const InstalledExtensionInfo>(details)->extension;
  96       DCHECK(extension);
  97       if (extensions::util::IsEphemeralApp(extension->id(), profile_)) {
  98         ++ephemeral_app_count_;
  99         if (ephemeral_app_count_ >= kGarbageCollectAppsTriggerCount)
 100           TriggerGarbageCollect(
 101               base::TimeDelta::FromSeconds(kGarbageCollectAppsInstallDelay));
 102       }
 103       break;
 104     }
 105     case chrome::NOTIFICATION_EXTENSION_UNINSTALLED: {
 106       const Extension* extension =
 107           content::Details<const Extension>(details).ptr();
 108       DCHECK(extension);
 109       if (extensions::util::IsEphemeralApp(extension->id(), profile_))
 110         --ephemeral_app_count_;
 111       break;
 112     }
 113     case chrome::NOTIFICATION_PROFILE_DESTROYED: {
 114       // Ideally we need to know when the extension system is shutting down.
 115       garbage_collect_apps_timer_.Stop();
 116       break;
 117     }
 118     default:
 119       NOTREACHED();
 120   }
 121 }
 122
 123 void EphemeralAppService::Init() {
 124   InitEphemeralAppCount();
 125   TriggerGarbageCollect(
 126       base::TimeDelta::FromSeconds(kGarbageCollectAppsStartupDelay));
 127
 128   garbage_collect_data_timer_.Start(
 129       FROM_HERE,
 130       base::TimeDelta::FromSeconds(kGarbageCollectDataStartupDelay),
 131       this,
 132       &EphemeralAppService::GarbageCollectData);
 133 }
 134
 135 void EphemeralAppService::InitEphemeralAppCount() {
 136   scoped_ptr<ExtensionSet> extensions =
 137       extensions::ExtensionRegistry::Get(profile_)
 138           ->GenerateInstalledExtensionsSet();
 139   ExtensionPrefs* prefs = ExtensionPrefs::Get(profile_);
 140   DCHECK(prefs);
 141
 142   ephemeral_app_count_ = 0;
 143   for (ExtensionSet::const_iterator it = extensions->begin();
 144        it != extensions->end(); ++it) {
 145     const Extension* extension = *it;
 146     if (prefs->IsEphemeralApp(extension->id()))
 147       ++ephemeral_app_count_;
 148   }
 149 }
 150
 151 void EphemeralAppService::TriggerGarbageCollect(const base::TimeDelta& delay) {
 152   if (!garbage_collect_apps_timer_.IsRunning()) {
 153     garbage_collect_apps_timer_.Start(
 154         FROM_HERE,
 155         delay,
 156         this,
 157         &EphemeralAppService::GarbageCollectApps);
 158   }
 159 }
 160
 161 void EphemeralAppService::GarbageCollectApps() {
 162   scoped_ptr<ExtensionSet> extensions =
 163       extensions::ExtensionRegistry::Get(profile_)
 164           ->GenerateInstalledExtensionsSet();
 165   ExtensionPrefs* prefs = ExtensionPrefs::Get(profile_);
 166   DCHECK(prefs);
 167
 168   int app_count = 0;
 169   LaunchTimeAppMap app_launch_times;
 170   std::set<std::string> remove_app_ids;
 171
 172   // Populate a list of ephemeral apps, ordered by their last launch time.
 173   for (ExtensionSet::const_iterator it = extensions->begin();
 174        it != extensions->end(); ++it) {
 175     const Extension* extension = *it;
 176     if (!prefs->IsEphemeralApp(extension->id()))
 177       continue;
 178
 179     ++app_count;
 180
 181     // Do not remove ephemeral apps that are running.
 182     if (!extensions::util::IsExtensionIdle(extension->id(), profile_))
 183       continue;
 184
 185     base::Time last_launch_time = prefs->GetLastLaunchTime(extension->id());
 186
 187     // If the last launch time is invalid, this may be because it was just
 188     // installed. So use the install time. If this is also null for some reason,
 189     // the app will be removed.
 190     if (last_launch_time.is_null())
 191       last_launch_time = prefs->GetInstallTime(extension->id());
 192
 193     app_launch_times.insert(std::make_pair(last_launch_time, extension->id()));
 194   }
 195
 196   ExtensionService* service =
 197       ExtensionSystem::Get(profile_)->extension_service();
 198   DCHECK(service);
 199   // Execute the replacement policies and remove apps marked for deletion.
 200   if (!app_launch_times.empty()) {
 201     GetAppsToRemove(app_count, app_launch_times, &remove_app_ids);
 202     for (std::set<std::string>::const_iterator id = remove_app_ids.begin();
 203          id != remove_app_ids.end(); ++id) {
 204       if (service->UninstallExtension(*id, false, NULL))
 205         --app_count;
 206     }
 207   }
 208
 209   ephemeral_app_count_ = app_count;
 210 }
 211
 212 // static
 213 void EphemeralAppService::GetAppsToRemove(
 214     int app_count,
 215     const LaunchTimeAppMap& app_launch_times,
 216     std::set<std::string>* remove_app_ids) {
 217   base::Time time_now = base::Time::Now();
 218   const base::Time inactive_threshold =
 219       time_now - base::TimeDelta::FromDays(kAppInactiveThreshold);
 220   const base::Time keep_threshold =
 221       time_now - base::TimeDelta::FromDays(kAppKeepThreshold);
 222
 223   // Visit the apps in order of least recently to most recently launched.
 224   for (LaunchTimeAppMap::const_iterator it = app_launch_times.begin();
 225        it != app_launch_times.end(); ++it) {
 226     // Cannot remove apps that have been launched recently. So break when we
 227     // reach the new apps.
 228     if (it->first > keep_threshold)
 229         break;
 230
 231     // Remove ephemeral apps that have been inactive for a while or if the cache
 232     // is larger than the desired size.
 233     if (it->first < inactive_threshold || app_count > kMaxEphemeralAppsCount) {
 234       remove_app_ids->insert(it->second);
 235       --app_count;
 236     } else {
 237       break;
 238     }
 239   }
 240 }
 241
 242 void EphemeralAppService::GarbageCollectData() {
 243   ExtensionService* service =
 244       ExtensionSystem::Get(profile_)->extension_service();
 245   DCHECK(service);
 246   ExtensionPrefs* prefs = ExtensionPrefs::Get(profile_);
 247   DCHECK(prefs);
 248   scoped_ptr<ExtensionPrefs::ExtensionsInfo> evicted_apps_info(
 249       prefs->GetEvictedEphemeralAppsInfo());
 250
 251   base::Time time_now = base::Time::Now();
 252   const base::Time inactive_threshold =
 253       time_now - base::TimeDelta::FromDays(kDataInactiveThreshold);
 254
 255   for (size_t i = 0; i < evicted_apps_info->size(); ++i) {
 256     ExtensionInfo* info = evicted_apps_info->at(i).get();
 257     base::Time last_launch_time = prefs->GetLastLaunchTime(info->extension_id);
 258     if (last_launch_time > inactive_threshold)
 259       continue;
 260
 261     // Sanity check to ensure the app is not currently installed.
 262     if (service->GetInstalledExtension(info->extension_id)) {
 263       NOTREACHED();
 264       continue;
 265     }
 266
 267     // Ensure the app is not waiting to be installed.
 268     scoped_ptr<ExtensionInfo> delayed_install(
 269         prefs->GetDelayedInstallInfo(info->extension_id));
 270     if (delayed_install.get())
 271       continue;
 272
 273     if (info->extension_manifest.get()) {
 274       std::string error;
 275       scoped_refptr<const Extension> extension(Extension::Create(
 276           info->extension_path,
 277           info->extension_location,
 278           *info->extension_manifest,
 279           prefs->GetCreationFlags(info->extension_id),
 280           info->extension_id,
 281           &error));
 282
 283       if (extension.get())
 284         extensions::DataDeleter::StartDeleting(profile_, extension.get());
 285     }
 286
 287     prefs->RemoveEvictedEphemeralApp(info->extension_id);
 288   }
 289 }