components/drive/file_system/download_operation.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 "components/drive/file_system/download_operation.h"
   6
   7 #include "base/callback_helpers.h"
   8 #include "base/files/file_path.h"
   9 #include "base/files/file_util.h"
  10 #include "base/logging.h"
  11 #include "base/task_runner_util.h"
  12 #include "components/drive/drive.pb.h"
  13 #include "components/drive/file_cache.h"
  14 #include "components/drive/file_change.h"
  15 #include "components/drive/file_errors.h"
  16 #include "components/drive/file_system/operation_delegate.h"
  17 #include "components/drive/file_system_core_util.h"
  18 #include "components/drive/job_scheduler.h"
  19 #include "components/drive/resource_metadata.h"
  20 #include "google_apis/drive/drive_api_error_codes.h"
  21
  22 namespace drive {
  23 namespace file_system {
  24 namespace {
  25
  26 // Generates an unused file path with |extension| to |out_path|, as a descendant
  27 // of |dir|, with its parent directory created.
  28 bool GeneratesUniquePathWithExtension(
  29     const base::FilePath& dir,
  30     const base::FilePath::StringType& extension,
  31     base::FilePath* out_path) {
  32   base::FilePath subdir;
  33   if (!base::CreateTemporaryDirInDir(dir, base::FilePath::StringType(),
  34                                      &subdir)) {
  35     return false;
  36   }
  37   *out_path = subdir.Append(FILE_PATH_LITERAL("tmp") + extension);
  38   return true;
  39 }
  40
  41 // Prepares for downloading the file. Allocates the enough space for the file
  42 // in the cache.
  43 // If succeeded, returns FILE_ERROR_OK with |temp_download_file| storing the
  44 // path to the file in the cache.
  45 FileError PrepareForDownloadFile(internal::FileCache* cache,
  46                                  int64 expected_file_size,
  47                                  const base::FilePath& temporary_file_directory,
  48                                  base::FilePath* temp_download_file) {
  49   DCHECK(cache);
  50   DCHECK(temp_download_file);
  51
  52   // Ensure enough space in the cache.
  53   if (!cache->FreeDiskSpaceIfNeededFor(expected_file_size))
  54     return FILE_ERROR_NO_LOCAL_SPACE;
  55
  56   return base::CreateTemporaryFileInDir(
  57       temporary_file_directory,
  58       temp_download_file) ? FILE_ERROR_OK : FILE_ERROR_FAILED;
  59 }
  60
  61 // If the resource is a hosted document, creates a JSON file representing the
  62 // resource locally, and returns FILE_ERROR_OK with |cache_file_path| storing
  63 // the path to the JSON file.
  64 // If the resource is a regular file and its local cache is available,
  65 // returns FILE_ERROR_OK with |cache_file_path| storing the path to the
  66 // cache file.
  67 // If the resource is a regular file but its local cache is NOT available,
  68 // returns FILE_ERROR_OK, but |cache_file_path| is kept empty.
  69 // Otherwise returns error code.
  70 FileError CheckPreConditionForEnsureFileDownloaded(
  71     internal::ResourceMetadata* metadata,
  72     internal::FileCache* cache,
  73     const base::FilePath& temporary_file_directory,
  74     const std::string& local_id,
  75     ResourceEntry* entry,
  76     base::FilePath* cache_file_path,
  77     base::FilePath* temp_download_file_path) {
  78   DCHECK(metadata);
  79   DCHECK(cache);
  80   DCHECK(cache_file_path);
  81
  82   FileError error = metadata->GetResourceEntryById(local_id, entry);
  83   if (error != FILE_ERROR_OK)
  84     return error;
  85
  86   if (entry->file_info().is_directory())
  87     return FILE_ERROR_NOT_A_FILE;
  88
  89   // For a hosted document, we create a special JSON file to represent the
  90   // document instead of fetching the document content in one of the exported
  91   // formats. The JSON file contains the edit URL and resource ID of the
  92   // document.
  93   if (entry->file_specific_info().is_hosted_document()) {
  94     base::FilePath::StringType extension = base::FilePath::FromUTF8Unsafe(
  95         entry->file_specific_info().document_extension()).value();
  96     base::FilePath gdoc_file_path;
  97     base::File::Info file_info;
  98     // We add the gdoc file extension in the temporary file, so that in cross
  99     // profile drag-and-drop between Drive folders, the destination profiles's
 100     // CopyOperation can detect the special JSON file only by the path.
 101     if (!GeneratesUniquePathWithExtension(temporary_file_directory,
 102                                           extension,
 103                                           &gdoc_file_path) ||
 104         !util::CreateGDocFile(gdoc_file_path,
 105                               GURL(entry->file_specific_info().alternate_url()),
 106                               entry->resource_id()) ||
 107         !base::GetFileInfo(gdoc_file_path,
 108                            reinterpret_cast<base::File::Info*>(&file_info)))
 109       return FILE_ERROR_FAILED;
 110
 111     *cache_file_path = gdoc_file_path;
 112     entry->mutable_file_info()->set_size(file_info.size);
 113     return FILE_ERROR_OK;
 114   }
 115
 116   if (!entry->file_specific_info().cache_state().is_present()) {
 117     // This file has no cache file.
 118     if (!entry->resource_id().empty()) {
 119       // This entry exists on the server, leave |cache_file_path| empty to
 120       // start download.
 121       return PrepareForDownloadFile(cache, entry->file_info().size(),
 122                                     temporary_file_directory,
 123                                     temp_download_file_path);
 124     }
 125
 126     // This entry does not exist on the server, store an empty file and mark it
 127     // as dirty.
 128     base::FilePath empty_file;
 129     if (!base::CreateTemporaryFileInDir(temporary_file_directory, &empty_file))
 130       return FILE_ERROR_FAILED;
 131     error = cache->Store(local_id, std::string(), empty_file,
 132                          internal::FileCache::FILE_OPERATION_MOVE);
 133     if (error != FILE_ERROR_OK)
 134       return error;
 135
 136     error = metadata->GetResourceEntryById(local_id, entry);
 137     if (error != FILE_ERROR_OK)
 138       return error;
 139   }
 140
 141   // Leave |cache_file_path| empty when the stored file is obsolete and has no
 142   // local modification.
 143   if (!entry->file_specific_info().cache_state().is_dirty() &&
 144       entry->file_specific_info().md5() !=
 145       entry->file_specific_info().cache_state().md5()) {
 146     return PrepareForDownloadFile(cache, entry->file_info().size(),
 147                                   temporary_file_directory,
 148                                   temp_download_file_path);
 149   }
 150
 151   // Fill |cache_file_path| with the path to the cached file.
 152   error = cache->GetFile(local_id, cache_file_path);
 153   if (error != FILE_ERROR_OK)
 154     return error;
 155
 156   // If the cache file is to be returned as the download result, the file info
 157   // of the cache needs to be returned via |entry|.
 158   // TODO(kinaba): crbug.com/246469. The logic below is similar to that in
 159   // drive::FileSystem::CheckLocalModificationAndRun. We should merge them.
 160   base::File::Info file_info;
 161   if (base::GetFileInfo(*cache_file_path, &file_info))
 162     entry->mutable_file_info()->set_size(file_info.size);
 163
 164   return FILE_ERROR_OK;
 165 }
 166
 167 struct CheckPreconditionForEnsureFileDownloadedParams {
 168   internal::ResourceMetadata* metadata;
 169   internal::FileCache* cache;
 170   base::FilePath temporary_file_directory;
 171 };
 172
 173 // Calls CheckPreConditionForEnsureFileDownloaded() with the entry specified by
 174 // the given ID. Also fills |drive_file_path| with the path of the entry.
 175 FileError CheckPreConditionForEnsureFileDownloadedByLocalId(
 176     const CheckPreconditionForEnsureFileDownloadedParams& params,
 177     const std::string& local_id,
 178     base::FilePath* drive_file_path,
 179     base::FilePath* cache_file_path,
 180     base::FilePath* temp_download_file_path,
 181     ResourceEntry* entry) {
 182   FileError error = params.metadata->GetFilePath(local_id, drive_file_path);
 183   if (error != FILE_ERROR_OK)
 184     return error;
 185   return CheckPreConditionForEnsureFileDownloaded(
 186       params.metadata, params.cache, params.temporary_file_directory, local_id,
 187       entry, cache_file_path, temp_download_file_path);
 188 }
 189
 190 // Calls CheckPreConditionForEnsureFileDownloaded() with the entry specified by
 191 // the given file path.
 192 FileError CheckPreConditionForEnsureFileDownloadedByPath(
 193     const CheckPreconditionForEnsureFileDownloadedParams& params,
 194     const base::FilePath& file_path,
 195     base::FilePath* cache_file_path,
 196     base::FilePath* temp_download_file_path,
 197     ResourceEntry* entry) {
 198   std::string local_id;
 199   FileError error = params.metadata->GetIdByPath(file_path, &local_id);
 200   if (error != FILE_ERROR_OK)
 201     return error;
 202   return CheckPreConditionForEnsureFileDownloaded(
 203       params.metadata, params.cache, params.temporary_file_directory, local_id,
 204       entry, cache_file_path, temp_download_file_path);
 205 }
 206
 207 // Stores the downloaded file at |downloaded_file_path| into |cache|.
 208 // If succeeded, returns FILE_ERROR_OK with |cache_file_path| storing the
 209 // path to the cache file.
 210 // If failed, returns an error code with deleting |downloaded_file_path|.
 211 FileError UpdateLocalStateForDownloadFile(
 212     internal::ResourceMetadata* metadata,
 213     internal::FileCache* cache,
 214     const ResourceEntry& entry_before_download,
 215     google_apis::DriveApiErrorCode gdata_error,
 216     const base::FilePath& downloaded_file_path,
 217     ResourceEntry* entry_after_update,
 218     base::FilePath* cache_file_path) {
 219   DCHECK(cache);
 220
 221   // Downloaded file should be deleted on errors.
 222   base::ScopedClosureRunner file_deleter(base::Bind(
 223       base::IgnoreResult(&base::DeleteFile),
 224       downloaded_file_path, false /* recursive */));
 225
 226   FileError error = GDataToFileError(gdata_error);
 227   if (error != FILE_ERROR_OK)
 228     return error;
 229
 230   const std::string& local_id = entry_before_download.local_id();
 231
 232   // Do not overwrite locally edited file with server side contents.
 233   ResourceEntry entry;
 234   error = metadata->GetResourceEntryById(local_id, &entry);
 235   if (error != FILE_ERROR_OK)
 236     return error;
 237   if (entry.file_specific_info().cache_state().is_dirty())
 238     return FILE_ERROR_IN_USE;
 239
 240   // Here the download is completed successfully, so store it into the cache.
 241   error = cache->Store(local_id,
 242                        entry_before_download.file_specific_info().md5(),
 243                        downloaded_file_path,
 244                        internal::FileCache::FILE_OPERATION_MOVE);
 245   if (error != FILE_ERROR_OK)
 246     return error;
 247   base::Closure unused_file_deleter_closure = file_deleter.Release();
 248
 249   error = metadata->GetResourceEntryById(local_id, entry_after_update);
 250   if (error != FILE_ERROR_OK)
 251     return error;
 252
 253   return cache->GetFile(local_id, cache_file_path);
 254 }
 255
 256 }  // namespace
 257
 258 class DownloadOperation::DownloadParams {
 259  public:
 260   DownloadParams(
 261       const GetFileContentInitializedCallback initialized_callback,
 262       const google_apis::GetContentCallback get_content_callback,
 263       const GetFileCallback completion_callback,
 264       scoped_ptr<ResourceEntry> entry)
 265       : initialized_callback_(initialized_callback),
 266         get_content_callback_(get_content_callback),
 267         completion_callback_(completion_callback),
 268         entry_(entry.Pass()),
 269         was_cancelled_(false),
 270         weak_ptr_factory_(this) {
 271     DCHECK(!completion_callback_.is_null());
 272     DCHECK(entry_);
 273   }
 274
 275   base::Closure GetCancelClosure() {
 276     return base::Bind(&DownloadParams::Cancel, weak_ptr_factory_.GetWeakPtr());
 277   }
 278
 279   void OnCacheFileFound(const base::FilePath& cache_file_path) {
 280     if (!initialized_callback_.is_null()) {
 281       initialized_callback_.Run(FILE_ERROR_OK, cache_file_path,
 282                                 make_scoped_ptr(new ResourceEntry(*entry_)));
 283     }
 284     completion_callback_.Run(FILE_ERROR_OK, cache_file_path, entry_.Pass());
 285   }
 286
 287   void OnStartDownloading(const base::Closure& cancel_download_closure) {
 288     cancel_download_closure_ = cancel_download_closure;
 289     if (initialized_callback_.is_null()) {
 290       return;
 291     }
 292
 293     DCHECK(entry_);
 294     initialized_callback_.Run(FILE_ERROR_OK, base::FilePath(),
 295                               make_scoped_ptr(new ResourceEntry(*entry_)));
 296   }
 297
 298   void OnError(FileError error) const {
 299     completion_callback_.Run(
 300         error, base::FilePath(), scoped_ptr<ResourceEntry>());
 301   }
 302
 303   void OnDownloadCompleted(const base::FilePath& cache_file_path,
 304                            scoped_ptr<ResourceEntry> entry) const {
 305     completion_callback_.Run(FILE_ERROR_OK, cache_file_path, entry.Pass());
 306   }
 307
 308   const google_apis::GetContentCallback& get_content_callback() const {
 309     return get_content_callback_;
 310   }
 311
 312   const ResourceEntry& entry() const { return *entry_; }
 313
 314   bool was_cancelled() const { return was_cancelled_; }
 315
 316  private:
 317   void Cancel() {
 318     was_cancelled_ = true;
 319     if (!cancel_download_closure_.is_null())
 320       cancel_download_closure_.Run();
 321   }
 322
 323   const GetFileContentInitializedCallback initialized_callback_;
 324   const google_apis::GetContentCallback get_content_callback_;
 325   const GetFileCallback completion_callback_;
 326
 327   scoped_ptr<ResourceEntry> entry_;
 328   base::Closure cancel_download_closure_;
 329   bool was_cancelled_;
 330
 331   base::WeakPtrFactory<DownloadParams> weak_ptr_factory_;
 332   DISALLOW_COPY_AND_ASSIGN(DownloadParams);
 333 };
 334
 335 DownloadOperation::DownloadOperation(
 336     base::SequencedTaskRunner* blocking_task_runner,
 337     OperationDelegate* delegate,
 338     JobScheduler* scheduler,
 339     internal::ResourceMetadata* metadata,
 340     internal::FileCache* cache,
 341     const base::FilePath& temporary_file_directory)
 342     : blocking_task_runner_(blocking_task_runner),
 343       delegate_(delegate),
 344       scheduler_(scheduler),
 345       metadata_(metadata),
 346       cache_(cache),
 347       temporary_file_directory_(temporary_file_directory),
 348       weak_ptr_factory_(this) {
 349 }
 350
 351 DownloadOperation::~DownloadOperation() {
 352 }
 353
 354 base::Closure DownloadOperation::EnsureFileDownloadedByLocalId(
 355     const std::string& local_id,
 356     const ClientContext& context,
 357     const GetFileContentInitializedCallback& initialized_callback,
 358     const google_apis::GetContentCallback& get_content_callback,
 359     const GetFileCallback& completion_callback) {
 360   DCHECK(thread_checker_.CalledOnValidThread());
 361   DCHECK(!completion_callback.is_null());
 362
 363   CheckPreconditionForEnsureFileDownloadedParams params;
 364   params.metadata = metadata_;
 365   params.cache = cache_;
 366   params.temporary_file_directory = temporary_file_directory_;
 367   base::FilePath* drive_file_path = new base::FilePath;
 368   base::FilePath* cache_file_path = new base::FilePath;
 369   base::FilePath* temp_download_file_path = new base::FilePath;
 370   ResourceEntry* entry = new ResourceEntry;
 371   scoped_ptr<DownloadParams> download_params(new DownloadParams(
 372       initialized_callback, get_content_callback, completion_callback,
 373       make_scoped_ptr(entry)));
 374   base::Closure cancel_closure = download_params->GetCancelClosure();
 375   base::PostTaskAndReplyWithResult(
 376       blocking_task_runner_.get(),
 377       FROM_HERE,
 378       base::Bind(&CheckPreConditionForEnsureFileDownloadedByLocalId,
 379                  params,
 380                  local_id,
 381                  drive_file_path,
 382                  cache_file_path,
 383                  temp_download_file_path,
 384                  entry),
 385       base::Bind(&DownloadOperation::EnsureFileDownloadedAfterCheckPreCondition,
 386                  weak_ptr_factory_.GetWeakPtr(),
 387                  base::Passed(&download_params),
 388                  context,
 389                  base::Owned(drive_file_path),
 390                  base::Owned(cache_file_path),
 391                  base::Owned(temp_download_file_path)));
 392   return cancel_closure;
 393 }
 394
 395 base::Closure DownloadOperation::EnsureFileDownloadedByPath(
 396     const base::FilePath& file_path,
 397     const ClientContext& context,
 398     const GetFileContentInitializedCallback& initialized_callback,
 399     const google_apis::GetContentCallback& get_content_callback,
 400     const GetFileCallback& completion_callback) {
 401   DCHECK(thread_checker_.CalledOnValidThread());
 402   DCHECK(!completion_callback.is_null());
 403
 404   CheckPreconditionForEnsureFileDownloadedParams params;
 405   params.metadata = metadata_;
 406   params.cache = cache_;
 407   params.temporary_file_directory = temporary_file_directory_;
 408   base::FilePath* drive_file_path = new base::FilePath(file_path);
 409   base::FilePath* cache_file_path = new base::FilePath;
 410   base::FilePath* temp_download_file_path = new base::FilePath;
 411   ResourceEntry* entry = new ResourceEntry;
 412   scoped_ptr<DownloadParams> download_params(new DownloadParams(
 413       initialized_callback, get_content_callback, completion_callback,
 414       make_scoped_ptr(entry)));
 415   base::Closure cancel_closure = download_params->GetCancelClosure();
 416   base::PostTaskAndReplyWithResult(
 417       blocking_task_runner_.get(),
 418       FROM_HERE,
 419       base::Bind(&CheckPreConditionForEnsureFileDownloadedByPath,
 420                  params,
 421                  file_path,
 422                  cache_file_path,
 423                  temp_download_file_path,
 424                  entry),
 425       base::Bind(&DownloadOperation::EnsureFileDownloadedAfterCheckPreCondition,
 426                  weak_ptr_factory_.GetWeakPtr(),
 427                  base::Passed(&download_params),
 428                  context,
 429                  base::Owned(drive_file_path),
 430                  base::Owned(cache_file_path),
 431                  base::Owned(temp_download_file_path)));
 432   return cancel_closure;
 433 }
 434
 435 void DownloadOperation::EnsureFileDownloadedAfterCheckPreCondition(
 436     scoped_ptr<DownloadParams> params,
 437     const ClientContext& context,
 438     base::FilePath* drive_file_path,
 439     base::FilePath* cache_file_path,
 440     base::FilePath* temp_download_file_path,
 441     FileError error) {
 442   DCHECK(thread_checker_.CalledOnValidThread());
 443   DCHECK(params);
 444   DCHECK(drive_file_path);
 445   DCHECK(cache_file_path);
 446
 447   if (error != FILE_ERROR_OK) {
 448     // During precondition check, an error is found.
 449     params->OnError(error);
 450     return;
 451   }
 452
 453   if (!cache_file_path->empty()) {
 454     // The cache file is found.
 455     params->OnCacheFileFound(*cache_file_path);
 456     return;
 457   }
 458
 459   if (params->was_cancelled()) {
 460     params->OnError(FILE_ERROR_ABORT);
 461     return;
 462   }
 463
 464   DCHECK(!params->entry().resource_id().empty());
 465   DownloadParams* params_ptr = params.get();
 466   JobID id = scheduler_->DownloadFile(
 467       *drive_file_path,
 468       params_ptr->entry().file_info().size(),
 469       *temp_download_file_path,
 470       params_ptr->entry().resource_id(),
 471       context,
 472       base::Bind(&DownloadOperation::EnsureFileDownloadedAfterDownloadFile,
 473                  weak_ptr_factory_.GetWeakPtr(),
 474                  *drive_file_path,
 475                  base::Passed(&params)),
 476       params_ptr->get_content_callback());
 477
 478   // Notify via |initialized_callback| if necessary.
 479   params_ptr->OnStartDownloading(
 480       base::Bind(&DownloadOperation::CancelJob,
 481                  weak_ptr_factory_.GetWeakPtr(), id));
 482 }
 483
 484 void DownloadOperation::EnsureFileDownloadedAfterDownloadFile(
 485     const base::FilePath& drive_file_path,
 486     scoped_ptr<DownloadParams> params,
 487     google_apis::DriveApiErrorCode gdata_error,
 488     const base::FilePath& downloaded_file_path) {
 489   DCHECK(thread_checker_.CalledOnValidThread());
 490
 491   DownloadParams* params_ptr = params.get();
 492   ResourceEntry* entry_after_update = new ResourceEntry;
 493   base::FilePath* cache_file_path = new base::FilePath;
 494   base::PostTaskAndReplyWithResult(
 495       blocking_task_runner_.get(),
 496       FROM_HERE,
 497       base::Bind(&UpdateLocalStateForDownloadFile,
 498                  metadata_,
 499                  cache_,
 500                  params_ptr->entry(),
 501                  gdata_error,
 502                  downloaded_file_path,
 503                  entry_after_update,
 504                  cache_file_path),
 505       base::Bind(&DownloadOperation::EnsureFileDownloadedAfterUpdateLocalState,
 506                  weak_ptr_factory_.GetWeakPtr(),
 507                  drive_file_path,
 508                  base::Passed(&params),
 509                  base::Passed(make_scoped_ptr(entry_after_update)),
 510                  base::Owned(cache_file_path)));
 511 }
 512
 513 void DownloadOperation::EnsureFileDownloadedAfterUpdateLocalState(
 514     const base::FilePath& file_path,
 515     scoped_ptr<DownloadParams> params,
 516     scoped_ptr<ResourceEntry> entry_after_update,
 517     base::FilePath* cache_file_path,
 518     FileError error) {
 519   DCHECK(thread_checker_.CalledOnValidThread());
 520
 521   if (error != FILE_ERROR_OK) {
 522     params->OnError(error);
 523     return;
 524   }
 525   DCHECK(!entry_after_update->file_info().is_directory());
 526
 527   FileChange changed_files;
 528   changed_files.Update(file_path, FileChange::FILE_TYPE_FILE,
 529                        FileChange::CHANGE_TYPE_ADD_OR_UPDATE);
 530   // Storing to cache changes the "offline available" status, hence notify.
 531   delegate_->OnFileChangedByOperation(changed_files);
 532   params->OnDownloadCompleted(*cache_file_path, entry_after_update.Pass());
 533 }
 534
 535 void DownloadOperation::CancelJob(JobID job_id) {
 536   scheduler_->CancelJob(job_id);
 537 }
 538
 539 }  // namespace file_system
 540 }  // namespace drive