components/drive/file_system/download_operation.h

   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 #ifndef COMPONENTS_DRIVE_FILE_SYSTEM_DOWNLOAD_OPERATION_H_
   6 #define COMPONENTS_DRIVE_FILE_SYSTEM_DOWNLOAD_OPERATION_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/memory/scoped_ptr.h"
  10 #include "base/threading/thread_checker.h"
  11 #include "components/drive/file_errors.h"
  12 #include "components/drive/file_system_interface.h"
  13 #include "components/drive/job_list.h"
  14 #include "google_apis/drive/drive_api_error_codes.h"
  15
  16 namespace base {
  17 class FilePath;
  18 class SequencedTaskRunner;
  19 }  // namespace base
  20
  21 namespace google_apis {
  22 class ResourceEntry;
  23 }  // namespace google_apis
  24
  25 namespace drive {
  26
  27 class JobScheduler;
  28 class ResourceEntry;
  29 struct ClientContext;
  30
  31 namespace internal {
  32 class FileCache;
  33 class ResourceMetadata;
  34 }  // namespace internal
  35
  36 namespace file_system {
  37
  38 class OperationDelegate;
  39
  40 class DownloadOperation {
  41  public:
  42   DownloadOperation(base::SequencedTaskRunner* blocking_task_runner,
  43                     OperationDelegate* delegate,
  44                     JobScheduler* scheduler,
  45                     internal::ResourceMetadata* metadata,
  46                     internal::FileCache* cache,
  47                     const base::FilePath& temporary_file_directory);
  48   ~DownloadOperation();
  49
  50   // Ensures that the file content specified by |local_id| is locally
  51   // downloaded and returns a closure to cancel the task.
  52   // For hosted documents, this method may create a JSON file representing the
  53   // file.
  54   // For regular files, if the locally cached file is found, returns it.
  55   // If not found, start to download the file from the server.
  56   // When a JSON file is created, the cache file is found or downloading is
  57   // being started, |initialized_callback| is called with |local_file|
  58   // for JSON file or the cache file, or with |cancel_download_closure| for
  59   // downloading.
  60   // During the downloading |get_content_callback| will be called periodically
  61   // with the downloaded content.
  62   // Upon completion or an error is found, |completion_callback| will be called.
  63   // |initialized_callback| and |get_content_callback| can be null if not
  64   // needed.
  65   // |completion_callback| must not be null.
  66   base::Closure EnsureFileDownloadedByLocalId(
  67       const std::string& local_id,
  68       const ClientContext& context,
  69       const GetFileContentInitializedCallback& initialized_callback,
  70       const google_apis::GetContentCallback& get_content_callback,
  71       const GetFileCallback& completion_callback);
  72
  73   // Does the same thing as EnsureFileDownloadedByLocalId for the file
  74   // specified by |file_path|.
  75   base::Closure EnsureFileDownloadedByPath(
  76       const base::FilePath& file_path,
  77       const ClientContext& context,
  78       const GetFileContentInitializedCallback& initialized_callback,
  79       const google_apis::GetContentCallback& get_content_callback,
  80       const GetFileCallback& completion_callback);
  81
  82  private:
  83   // Parameters for EnsureFileDownloaded.
  84   class DownloadParams;
  85
  86   // Part of EnsureFileDownloaded(). Called upon the completion of precondition
  87   // check.
  88   void EnsureFileDownloadedAfterCheckPreCondition(
  89       scoped_ptr<DownloadParams> params,
  90       const ClientContext& context,
  91       base::FilePath* drive_file_path,
  92       base::FilePath* cache_file_path,
  93       base::FilePath* temp_download_file_path,
  94       FileError error);
  95
  96   // Part of EnsureFileDownloaded(). Called after the actual downloading.
  97   void EnsureFileDownloadedAfterDownloadFile(
  98       const base::FilePath& drive_file_path,
  99       scoped_ptr<DownloadParams> params,
 100       google_apis::DriveApiErrorCode gdata_error,
 101       const base::FilePath& downloaded_file_path);
 102
 103   // Part of EnsureFileDownloaded(). Called after updating local state is
 104   // completed.
 105   void EnsureFileDownloadedAfterUpdateLocalState(
 106       const base::FilePath& file_path,
 107       scoped_ptr<DownloadParams> params,
 108       scoped_ptr<ResourceEntry> entry_after_update,
 109       base::FilePath* cache_file_path,
 110       FileError error);
 111
 112   // Cancels the job with |job_id| in the scheduler.
 113   void CancelJob(JobID job_id);
 114
 115   scoped_refptr<base::SequencedTaskRunner> blocking_task_runner_;
 116   OperationDelegate* delegate_;
 117   JobScheduler* scheduler_;
 118   internal::ResourceMetadata* metadata_;
 119   internal::FileCache* cache_;
 120   const base::FilePath temporary_file_directory_;
 121
 122   base::ThreadChecker thread_checker_;
 123
 124   // Note: This should remain the last member so it'll be destroyed and
 125   // invalidate its weak pointers before any other members are destroyed.
 126   base::WeakPtrFactory<DownloadOperation> weak_ptr_factory_;
 127   DISALLOW_COPY_AND_ASSIGN(DownloadOperation);
 128 };
 129
 130 }  // namespace file_system
 131 }  // namespace drive
 132
 133 #endif  // COMPONENTS_DRIVE_FILE_SYSTEM_DOWNLOAD_OPERATION_H_