src/chrome/browser/sync_file_system/drive_backend_v1/remote_sync_delegate.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/sync_file_system/drive_backend_v1/remote_sync_delegate.h"
   6
   7 #include "base/file_util.h"
   8 #include "chrome/browser/sync_file_system/drive_backend_v1/remote_sync_operation_resolver.h"
   9 #include "chrome/browser/sync_file_system/logger.h"
  10 #include "chrome/browser/sync_file_system/remote_change_processor.h"
  11 #include "chrome/browser/sync_file_system/syncable_file_system_util.h"
  12
  13 using fileapi::FileSystemURL;
  14
  15 namespace {
  16
  17 void EmptyStatusCallback(sync_file_system::SyncStatusCode status) {}
  18
  19 }  // namespace
  20
  21 namespace sync_file_system {
  22 namespace drive_backend {
  23
  24 RemoteSyncDelegate::RemoteSyncDelegate(
  25     DriveFileSyncService* sync_service,
  26     const RemoteChange& remote_change)
  27     : sync_service_(sync_service),
  28       remote_change_(remote_change),
  29       sync_action_(SYNC_ACTION_NONE),
  30       metadata_updated_(false),
  31       clear_local_changes_(true) {
  32 }
  33
  34 RemoteSyncDelegate::~RemoteSyncDelegate() {}
  35
  36 void RemoteSyncDelegate::Run(const SyncStatusCallback& callback) {
  37   util::Log(logging::LOG_VERBOSE, FROM_HERE,
  38             "ProcessRemoteChange for %s change:%s",
  39             url().DebugString().c_str(),
  40             remote_file_change().DebugString().c_str());
  41
  42   remote_change_processor()->PrepareForProcessRemoteChange(
  43       url(),
  44       base::Bind(&RemoteSyncDelegate::DidPrepareForProcessRemoteChange,
  45                  AsWeakPtr(), callback));
  46 }
  47
  48 void RemoteSyncDelegate::DidPrepareForProcessRemoteChange(
  49     const SyncStatusCallback& callback,
  50     SyncStatusCode status,
  51     const SyncFileMetadata& metadata,
  52     const FileChangeList& local_changes) {
  53   if (status != SYNC_STATUS_OK) {
  54     AbortSync(callback, status);
  55     return;
  56   }
  57
  58   local_metadata_ = metadata;
  59   status = metadata_store()->ReadEntry(url(), &drive_metadata_);
  60   DCHECK(status == SYNC_STATUS_OK || status == SYNC_DATABASE_ERROR_NOT_FOUND);
  61
  62   bool missing_db_entry = (status != SYNC_STATUS_OK);
  63   if (missing_db_entry) {
  64     drive_metadata_.set_resource_id(remote_change_.resource_id);
  65     drive_metadata_.set_md5_checksum(std::string());
  66     drive_metadata_.set_conflicted(false);
  67     drive_metadata_.set_to_be_fetched(false);
  68   }
  69   bool missing_local_file = (metadata.file_type == SYNC_FILE_TYPE_UNKNOWN);
  70
  71   if (drive_metadata_.resource_id().empty()) {
  72     // This (missing_db_entry is false but resource_id is empty) could
  73     // happen when the remote file gets deleted (this clears resource_id
  74     // in drive_metadata) but then a file is added with the same name.
  75     drive_metadata_.set_resource_id(remote_change_.resource_id);
  76   }
  77
  78   SyncOperationType operation =
  79       RemoteSyncOperationResolver::Resolve(remote_file_change(),
  80                                            local_changes,
  81                                            local_metadata_.file_type,
  82                                            drive_metadata_.conflicted());
  83
  84   util::Log(logging::LOG_VERBOSE, FROM_HERE,
  85             "ProcessRemoteChange for %s %s%sremote_change: %s ==> %s",
  86             url().DebugString().c_str(),
  87             drive_metadata_.conflicted() ? " (conflicted)" : " ",
  88             missing_local_file ? " (missing local file)" : " ",
  89             remote_file_change().DebugString().c_str(),
  90             SyncOperationTypeToString(operation));
  91   DCHECK_NE(SYNC_OPERATION_FAIL, operation);
  92
  93   switch (operation) {
  94     case SYNC_OPERATION_ADD_FILE:
  95     case SYNC_OPERATION_ADD_DIRECTORY:
  96       sync_action_ = SYNC_ACTION_ADDED;
  97       break;
  98     case SYNC_OPERATION_UPDATE_FILE:
  99       sync_action_ = SYNC_ACTION_UPDATED;
 100       break;
 101     case SYNC_OPERATION_DELETE:
 102       sync_action_ = SYNC_ACTION_DELETED;
 103       break;
 104     case SYNC_OPERATION_NONE:
 105     case SYNC_OPERATION_DELETE_METADATA:
 106       sync_action_ = SYNC_ACTION_NONE;
 107       break;
 108     default:
 109       break;
 110   }
 111
 112   switch (operation) {
 113     case SYNC_OPERATION_ADD_FILE:
 114     case SYNC_OPERATION_UPDATE_FILE:
 115       DownloadFile(callback);
 116       return;
 117     case SYNC_OPERATION_ADD_DIRECTORY:
 118     case SYNC_OPERATION_DELETE:
 119       ApplyRemoteChange(callback);
 120       return;
 121     case SYNC_OPERATION_NONE:
 122       CompleteSync(callback, SYNC_STATUS_OK);
 123       return;
 124     case SYNC_OPERATION_CONFLICT:
 125       HandleConflict(callback, remote_file_change().file_type());
 126       return;
 127     case SYNC_OPERATION_RESOLVE_TO_LOCAL:
 128       ResolveToLocal(callback);
 129       return;
 130     case SYNC_OPERATION_RESOLVE_TO_REMOTE:
 131       ResolveToRemote(callback);
 132       return;
 133     case SYNC_OPERATION_DELETE_METADATA:
 134       if (missing_db_entry)
 135         CompleteSync(callback, SYNC_STATUS_OK);
 136       else
 137         DeleteMetadata(callback);
 138       return;
 139     case SYNC_OPERATION_FAIL:
 140       AbortSync(callback, SYNC_STATUS_FAILED);
 141       return;
 142   }
 143   NOTREACHED();
 144   AbortSync(callback, SYNC_STATUS_FAILED);
 145 }
 146
 147 void RemoteSyncDelegate::ApplyRemoteChange(const SyncStatusCallback& callback) {
 148   remote_change_processor()->ApplyRemoteChange(
 149       remote_file_change(), temporary_file_.path(), url(),
 150       base::Bind(&RemoteSyncDelegate::DidApplyRemoteChange, AsWeakPtr(),
 151                  callback));
 152 }
 153
 154 void RemoteSyncDelegate::DidApplyRemoteChange(
 155     const SyncStatusCallback& callback,
 156     SyncStatusCode status) {
 157   if (status != SYNC_STATUS_OK) {
 158     AbortSync(callback, status);
 159     return;
 160   }
 161
 162   if (remote_file_change().IsDelete()) {
 163     DeleteMetadata(callback);
 164     return;
 165   }
 166
 167   drive_metadata_.set_resource_id(remote_change_.resource_id);
 168   drive_metadata_.set_conflicted(false);
 169   if (remote_file_change().IsFile()) {
 170     drive_metadata_.set_type(DriveMetadata::RESOURCE_TYPE_FILE);
 171   } else {
 172     NOTREACHED();
 173     drive_metadata_.set_type(DriveMetadata::RESOURCE_TYPE_FOLDER);
 174   }
 175
 176   metadata_store()->UpdateEntry(
 177       url(), drive_metadata_,
 178       base::Bind(&RemoteSyncDelegate::CompleteSync,
 179                  AsWeakPtr(), callback));
 180 }
 181
 182 void RemoteSyncDelegate::DeleteMetadata(const SyncStatusCallback& callback) {
 183   metadata_store()->DeleteEntry(
 184       url(),
 185       base::Bind(&RemoteSyncDelegate::CompleteSync, AsWeakPtr(), callback));
 186 }
 187
 188 void RemoteSyncDelegate::DownloadFile(const SyncStatusCallback& callback) {
 189   // We should not use the md5 in metadata for FETCH type to avoid the download
 190   // finishes due to NOT_MODIFIED.
 191   std::string md5_checksum;
 192   if (!drive_metadata_.to_be_fetched())
 193     md5_checksum = drive_metadata_.md5_checksum();
 194
 195   api_util()->DownloadFile(
 196       remote_change_.resource_id,
 197       md5_checksum,
 198       base::Bind(&RemoteSyncDelegate::DidDownloadFile,
 199                  AsWeakPtr(),
 200                  callback));
 201 }
 202
 203 void RemoteSyncDelegate::DidDownloadFile(
 204     const SyncStatusCallback& callback,
 205     google_apis::GDataErrorCode error,
 206     const std::string& md5_checksum,
 207     int64 file_size,
 208     const base::Time& updated_time,
 209     webkit_blob::ScopedFile downloaded_file) {
 210   if (error == google_apis::HTTP_NOT_MODIFIED) {
 211     sync_action_ = SYNC_ACTION_NONE;
 212     DidApplyRemoteChange(callback, SYNC_STATUS_OK);
 213     return;
 214   }
 215
 216   // File may be deleted. If this was for new file it's ok, if this was
 217   // for existing file we'll process the delete change later.
 218   if (error == google_apis::HTTP_NOT_FOUND) {
 219     sync_action_ = SYNC_ACTION_NONE;
 220     DidApplyRemoteChange(callback, SYNC_STATUS_OK);
 221     return;
 222   }
 223
 224   SyncStatusCode status = GDataErrorCodeToSyncStatusCodeWrapper(error);
 225   if (status != SYNC_STATUS_OK) {
 226     AbortSync(callback, status);
 227     return;
 228   }
 229
 230   temporary_file_ = downloaded_file.Pass();
 231   drive_metadata_.set_md5_checksum(md5_checksum);
 232   remote_change_processor()->ApplyRemoteChange(
 233       remote_file_change(), temporary_file_.path(), url(),
 234       base::Bind(&RemoteSyncDelegate::DidApplyRemoteChange,
 235                  AsWeakPtr(), callback));
 236 }
 237
 238 void RemoteSyncDelegate::HandleConflict(
 239     const SyncStatusCallback& callback,
 240     SyncFileType remote_file_type) {
 241   ConflictResolution resolution = conflict_resolution_resolver()->Resolve(
 242       local_metadata_.file_type,
 243       local_metadata_.last_modified,
 244       remote_file_type,
 245       remote_change_.updated_time);
 246
 247   switch (resolution) {
 248     case CONFLICT_RESOLUTION_LOCAL_WIN:
 249       HandleLocalWin(callback);
 250       return;
 251     case CONFLICT_RESOLUTION_REMOTE_WIN:
 252       HandleRemoteWin(callback, remote_file_type);
 253       return;
 254     case CONFLICT_RESOLUTION_MARK_CONFLICT:
 255       HandleManualResolutionCase(callback);
 256       return;
 257     case CONFLICT_RESOLUTION_UNKNOWN:
 258       // Get remote file time and call this method again.
 259       api_util()->GetResourceEntry(
 260           remote_change_.resource_id,
 261           base::Bind(
 262               &RemoteSyncDelegate::DidGetEntryForConflictResolution,
 263               AsWeakPtr(), callback));
 264       return;
 265   }
 266   NOTREACHED();
 267   AbortSync(callback, SYNC_STATUS_FAILED);
 268 }
 269
 270 void RemoteSyncDelegate::HandleLocalWin(
 271     const SyncStatusCallback& callback) {
 272   util::Log(logging::LOG_VERBOSE, FROM_HERE,
 273             "Resolving conflict for remote sync: %s: LOCAL WIN",
 274             url().DebugString().c_str());
 275   ResolveToLocal(callback);
 276 }
 277
 278 void RemoteSyncDelegate::HandleRemoteWin(
 279     const SyncStatusCallback& callback,
 280     SyncFileType remote_file_type) {
 281   // Make sure we reset the conflict flag and start over the remote sync
 282   // with empty local changes.
 283   util::Log(logging::LOG_VERBOSE, FROM_HERE,
 284             "Resolving conflict for remote sync: %s: REMOTE WIN",
 285             url().DebugString().c_str());
 286
 287   drive_metadata_.set_conflicted(false);
 288   drive_metadata_.set_to_be_fetched(false);
 289   drive_metadata_.set_type(
 290       DriveFileSyncService::SyncFileTypeToDriveMetadataResourceType(
 291           remote_file_type));
 292   metadata_store()->UpdateEntry(
 293       url(), drive_metadata_,
 294       base::Bind(&RemoteSyncDelegate::StartOver, AsWeakPtr(), callback));
 295 }
 296
 297 void RemoteSyncDelegate::HandleManualResolutionCase(
 298     const SyncStatusCallback& callback) {
 299   sync_action_ = SYNC_ACTION_NONE;
 300   sync_service_->MarkConflict(
 301       url(), &drive_metadata_,
 302       base::Bind(&RemoteSyncDelegate::CompleteSync, AsWeakPtr(), callback));
 303 }
 304
 305 void RemoteSyncDelegate::DidGetEntryForConflictResolution(
 306     const SyncStatusCallback& callback,
 307     google_apis::GDataErrorCode error,
 308     scoped_ptr<google_apis::ResourceEntry> entry) {
 309   SyncStatusCode status = GDataErrorCodeToSyncStatusCodeWrapper(error);
 310   if (status != SYNC_STATUS_OK || entry->updated_time().is_null()) {
 311     HandleLocalWin(callback);
 312     return;
 313   }
 314
 315   SyncFileType file_type = SYNC_FILE_TYPE_UNKNOWN;
 316   if (entry->is_file())
 317     file_type = SYNC_FILE_TYPE_FILE;
 318   if (entry->is_folder())
 319     file_type = SYNC_FILE_TYPE_DIRECTORY;
 320
 321   remote_change_.updated_time = entry->updated_time();
 322   HandleConflict(callback, file_type);
 323 }
 324
 325 void RemoteSyncDelegate::ResolveToLocal(
 326     const SyncStatusCallback& callback) {
 327   sync_action_ = SYNC_ACTION_NONE;
 328   clear_local_changes_ = false;
 329
 330   // Re-add a fake local change to resolve it later in next LocalSync.
 331   remote_change_processor()->RecordFakeLocalChange(
 332       url(),
 333       FileChange(FileChange::FILE_CHANGE_ADD_OR_UPDATE,
 334                  local_metadata_.file_type),
 335       base::Bind(&RemoteSyncDelegate::DidResolveToLocal,
 336                  AsWeakPtr(), callback));
 337 }
 338
 339 void RemoteSyncDelegate::DidResolveToLocal(
 340     const SyncStatusCallback& callback,
 341     SyncStatusCode status) {
 342   if (status != SYNC_STATUS_OK) {
 343     DCHECK_NE(SYNC_STATUS_HAS_CONFLICT, status);
 344     AbortSync(callback, status);
 345     return;
 346   }
 347
 348   if (remote_file_change().IsDelete()) {
 349     metadata_store()->DeleteEntry(
 350         url(),
 351         base::Bind(&RemoteSyncDelegate::CompleteSync,
 352                    AsWeakPtr(), callback));
 353   } else {
 354     DCHECK(!remote_change_.resource_id.empty());
 355     drive_metadata_.set_resource_id(remote_change_.resource_id);
 356     drive_metadata_.set_conflicted(false);
 357     drive_metadata_.set_to_be_fetched(false);
 358     drive_metadata_.set_md5_checksum(std::string());
 359     metadata_store()->UpdateEntry(
 360         url(), drive_metadata_,
 361         base::Bind(&RemoteSyncDelegate::CompleteSync,
 362                    AsWeakPtr(), callback));
 363   }
 364 }
 365
 366 void RemoteSyncDelegate::ResolveToRemote(
 367     const SyncStatusCallback& callback) {
 368   drive_metadata_.set_conflicted(false);
 369   drive_metadata_.set_to_be_fetched(true);
 370   metadata_store()->UpdateEntry(
 371       url(), drive_metadata_,
 372       base::Bind(&RemoteSyncDelegate::DidResolveToRemote,
 373                  AsWeakPtr(), callback));
 374 }
 375
 376 void RemoteSyncDelegate::DidResolveToRemote(
 377     const SyncStatusCallback& callback,
 378     SyncStatusCode status) {
 379   if (status != SYNC_STATUS_OK) {
 380     AbortSync(callback, status);
 381     return;
 382   }
 383
 384   sync_action_ = SYNC_ACTION_ADDED;
 385   if (remote_file_change().file_type() == SYNC_FILE_TYPE_FILE) {
 386     DownloadFile(callback);
 387     return;
 388   }
 389
 390   // ApplyRemoteChange should replace any existing local file or
 391   // directory with remote_change_.
 392   ApplyRemoteChange(callback);
 393 }
 394
 395 void RemoteSyncDelegate::StartOver(
 396     const SyncStatusCallback& callback,
 397     SyncStatusCode status) {
 398   DidPrepareForProcessRemoteChange(
 399       callback, status, local_metadata_, FileChangeList());
 400 }
 401
 402 void RemoteSyncDelegate::CompleteSync(
 403     const SyncStatusCallback& callback,
 404     SyncStatusCode status) {
 405   if (status != SYNC_STATUS_OK) {
 406     AbortSync(callback, status);
 407     return;
 408   }
 409
 410   sync_service_->RemoveRemoteChange(url());
 411
 412   if (drive_metadata_.to_be_fetched()) {
 413     // Clear |to_be_fetched| flag since we completed fetching the remote change
 414     // and applying it to the local file.
 415     DCHECK(!drive_metadata_.conflicted());
 416     drive_metadata_.set_conflicted(false);
 417     drive_metadata_.set_to_be_fetched(false);
 418     metadata_store()->UpdateEntry(url(), drive_metadata_,
 419                                   base::Bind(&EmptyStatusCallback));
 420   }
 421
 422   if (remote_change_.changestamp > 0) {
 423     DCHECK(metadata_store()->IsIncrementalSyncOrigin(url().origin()));
 424     metadata_store()->SetLargestChangeStamp(
 425         remote_change_.changestamp,
 426         base::Bind(&RemoteSyncDelegate::DidFinish, AsWeakPtr(), callback));
 427     return;
 428   }
 429
 430   if (drive_metadata_.conflicted())
 431     status = SYNC_STATUS_HAS_CONFLICT;
 432
 433   DidFinish(callback, status);
 434 }
 435
 436 void RemoteSyncDelegate::AbortSync(
 437     const SyncStatusCallback& callback,
 438     SyncStatusCode status) {
 439   clear_local_changes_ = false;
 440   DidFinish(callback, status);
 441 }
 442
 443 void RemoteSyncDelegate::DidFinish(
 444     const SyncStatusCallback& callback,
 445     SyncStatusCode status) {
 446   remote_change_processor()->FinalizeRemoteSync(
 447       url(), clear_local_changes_,
 448       base::Bind(&RemoteSyncDelegate::DispatchCallbackAfterDidFinish,
 449                  AsWeakPtr(), callback, status));
 450 }
 451
 452 void RemoteSyncDelegate::DispatchCallbackAfterDidFinish(
 453     const SyncStatusCallback& callback,
 454     SyncStatusCode status) {
 455   if (status == SYNC_STATUS_OK && sync_action_ != SYNC_ACTION_NONE) {
 456     sync_service_->NotifyObserversFileStatusChanged(
 457         url(),
 458         SYNC_FILE_STATUS_SYNCED,
 459         sync_action_,
 460         SYNC_DIRECTION_REMOTE_TO_LOCAL);
 461   }
 462
 463   callback.Run(status);
 464 }
 465
 466 SyncStatusCode RemoteSyncDelegate::GDataErrorCodeToSyncStatusCodeWrapper(
 467     google_apis::GDataErrorCode error) {
 468   return sync_service_->GDataErrorCodeToSyncStatusCodeWrapper(error);
 469 }
 470
 471 DriveMetadataStore* RemoteSyncDelegate::metadata_store() {
 472   return sync_service_->metadata_store_.get();
 473 }
 474
 475 APIUtilInterface* RemoteSyncDelegate::api_util() {
 476   return sync_service_->api_util_.get();
 477 }
 478
 479 RemoteChangeHandler* RemoteSyncDelegate::remote_change_handler() {
 480   return &sync_service_->remote_change_handler_;
 481 }
 482
 483 RemoteChangeProcessor* RemoteSyncDelegate::remote_change_processor() {
 484   return sync_service_->remote_change_processor_;
 485 }
 486
 487 ConflictResolutionResolver* RemoteSyncDelegate::conflict_resolution_resolver() {
 488   return &sync_service_->conflict_resolution_resolver_;
 489 }
 490
 491 }  // namespace drive_backend
 492 }  // namespace sync_file_system