drive: Add DownloadOperation::EnsureFileDownloadedByResourceId

chrome/browser/chromeos/drive/file_system/download_operation.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_CHROMEOS_DRIVE_FILE_SYSTEM_DOWNLOAD_OPERATION_H_
 #define CHROME_BROWSER_CHROMEOS_DRIVE_FILE_SYSTEM_DOWNLOAD_OPERATION_H_
 
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
 #include "chrome/browser/chromeos/drive/file_errors.h"
@@ skipping 27 matching lines @@
 
 class DownloadOperation {
  public:
   DownloadOperation(base::SequencedTaskRunner* blocking_task_runner,
                     OperationObserver* observer,
                     JobScheduler* scheduler,
                     internal::ResourceMetadata* metadata,
                     internal::FileCache* cache);
   ~DownloadOperation();
 
   // Ensures that the file content is locally downloaded.

[satorux1, 2013/05/30 01:14:35]

the file content, specified by |resource_id|,

[hashimoto, 2013/05/30 01:47:25]

Done.

   // For hosted documents, this method may create a JSON file representing the
   // file.
   // For regular files, if the locally cached file is found, returns it.
   // If not found, start to download the file from the server.
   // When a JSON file is created, the cache file is found or downloading is
   // being started, |initialized_callback| is called with |local_file|
   // for JSON file or the cache file, or with |cancel_download_closure| for
   // downloading.
   // During the downloading |get_content_callback| will be called periodically
   // with the downloaded content.
   // Upon completion or an error is found, |completion_callback| will be
   // called.
   // |initialized_callback| and |get_content_callback| can be null if not
   // needed.
   // |completion_callback| must not be null.
-  void EnsureFileDownloaded(
+  void EnsureFileDownloadedByResourceId(

[satorux1, 2013/05/30 01:14:35]

Could you add a test for this function? you might want to introduce
download_operation_unittest.cc first... kinaba@ is in the process of moving test
code from file_system_unittest.cc to file_system/*_unittest.cc, so he may have
already started doing this for download_operation.

if it's too much of hassle, you can file a bug and do it later.  

[hashimoto, 2013/05/30 01:47:25]

This method is tested by FileSystemTest.GetFileByResourceID*.
To make independent unit test for download_operation.cc, kinaba@ has filed
http://crbug.com/244344.

+      const std::string& resource_id,
+      const ClientContext& context,
+      const GetFileContentInitializedCallback& initialized_callback,
+      const google_apis::GetContentCallback& get_content_callback,
+      const GetFileCallback& completion_callback);
+
+  // Does the same thing as EnsureFileDownloadedByResourceId for the file
+  // specified with |file_path|.
+  void EnsureFileDownloadedByPath(
       const base::FilePath& file_path,
       const ClientContext& context,
       const GetFileContentInitializedCallback& initialized_callback,
       const google_apis::GetContentCallback& get_content_callback,
       const GetFileCallback& completion_callback);
 
  private:
   // Thin wrapper of Callbacks for EnsureFileDownloaded.
   class DownloadCallback;
 
   // Parameters for JobScheduler::DownloadFile.
   struct DownloadParams;
 
   // Part of EnsureFileDownloaded(). Called upon the completion of precondition
   // check.
   void EnsureFileDownloadedAfterCheckPreCondition(
-      const base::FilePath& file_path,
       const ClientContext& context,
       const DownloadCallback& callback,
       scoped_ptr<ResourceEntry> entry,
       base::FilePath* cache_file_path,
       FileError error);
 
   // Part of EnsureFileDownloaded(). Called upon the completion of fetching
   // ResourceEntry from the server.
   void EnsureFileDownloadedAfterGetResourceEntry(
       const ClientContext& context,
@@ skipping 37 matching lines @@
   // Note: This should remain the last member so it'll be destroyed and
   // invalidate its weak pointers before any other members are destroyed.
   base::WeakPtrFactory<DownloadOperation> weak_ptr_factory_;
   DISALLOW_COPY_AND_ASSIGN(DownloadOperation);
 };
 
 }  // namespace file_system
 }  // namespace drive
 
 #endif  // CHROME_BROWSER_CHROMEOS_DRIVE_FILE_SYSTEM_DOWNLOAD_OPERATION_H_