drive: Make DownloadOperation aware of locally created files

Store an empty file to the cache when the entry is locally created one.

BUG=260539
TEST=unit_tests
R=kinaba@chromium.org

Review URL: https://codereview.chromium.org/132883010

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@247434 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 71 insertions, 6 deletions

diff --git a/chrome/browser/chromeos/drive/file_system/download_operation.cc b/chrome/browser/chromeos/drive/file_system/download_operation.cc
index 0df9748..6bb88ac 100644
--- a/chrome/browser/chromeos/drive/file_system/download_operation.cc
+++ b/chrome/browser/chromeos/drive/file_system/download_operation.cc
@@ -4,6 +4,7 @@
 
 #include "chrome/browser/chromeos/drive/file_system/download_operation.h"
 
+#include "base/callback_helpers.h"
 #include "base/file_util.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
@@ -52,9 +53,6 @@ FileError CheckPreConditionForEnsureFileDownloaded(
   if (entry->file_info().is_directory())
     return FILE_ERROR_NOT_A_FILE;
 
-  // The file's entry should have its file specific info.
-  DCHECK(entry->has_file_specific_info());
-
   // For a hosted document, we create a special JSON file to represent the
   // document instead of fetching the document content in one of the exported
   // formats. The JSON file contains the edit URL and resource ID of the
@@ -77,10 +75,32 @@ FileError CheckPreConditionForEnsureFileDownloaded(
     return FILE_ERROR_OK;
   }
 
-  // Leave |cache_file_path| empty when no cache entry is found.
   FileCacheEntry cache_entry;
-  if (!cache->GetCacheEntry(local_id, &cache_entry))
-    return FILE_ERROR_OK;
+  if (!cache->GetCacheEntry(local_id, &cache_entry) ||
+      !cache_entry.is_present()) {  // This file has no cache file.
+    if (!entry->resource_id().empty()) {
+      // This entry exists on the server, leave |cache_file_path| empty to
+      // start download.
+      return FILE_ERROR_OK;
+    }
+
+    // This entry does not exist on the server, store an empty file and mark it
+    // as dirty.
+    base::FilePath empty_file;
+    if (!base::CreateTemporaryFileInDir(temporary_file_directory, &empty_file))
+      return FILE_ERROR_FAILED;
+    error = cache->Store(local_id, base::MD5String(""), empty_file,
+                         internal::FileCache::FILE_OPERATION_MOVE);
+    if (error != FILE_ERROR_OK)
+      return error;
+    scoped_ptr<base::ScopedClosureRunner> file_closer;
+    error = cache->OpenForWrite(entry->local_id(), &file_closer);
+    if (error != FILE_ERROR_OK)
+      return error;
+
+    if (!cache->GetCacheEntry(local_id, &cache_entry))
+      return FILE_ERROR_NOT_FOUND;
+  }
 
   // Leave |cache_file_path| empty when the stored file is obsolete and has no
   // local modification.
@@ -383,6 +403,8 @@ void DownloadOperation::EnsureFileDownloadedAfterCheckPreCondition(
     return;
   }
 
+  DCHECK(!params->entry().resource_id().empty());
+
   // If cache file is not found, try to download the file from the server
   // instead. Check if we have enough space, based on the expected file size.
   // - if we don't have enough space, try to free up the disk space
diff --git a/chrome/browser/chromeos/drive/file_system/download_operation_unittest.cc b/chrome/browser/chromeos/drive/file_system/download_operation_unittest.cc
index 5aaedfc..a706a37 100644
--- a/chrome/browser/chromeos/drive/file_system/download_operation_unittest.cc
+++ b/chrome/browser/chromeos/drive/file_system/download_operation_unittest.cc
@@ -469,5 +469,48 @@ TEST_F(DownloadOperationTest, EnsureFileDownloadedByPath_DirtyCache) {
   EXPECT_EQ(static_cast<int64>(dirty_size), entry->file_info().size());
 }
 
+TEST_F(DownloadOperationTest, EnsureFileDownloadedByPath_LocallyCreatedFile) {
+  // Add a new file with an empty resource ID.
+  base::FilePath file_path(FILE_PATH_LITERAL("drive/root/New File.txt"));
+  ResourceEntry parent;
+  ASSERT_EQ(FILE_ERROR_OK, GetLocalResourceEntry(file_path.DirName(), &parent));
+
+  ResourceEntry new_file;
+  new_file.set_title("New File.txt");
+  new_file.set_parent_local_id(parent.local_id());
+
+  FileError error = FILE_ERROR_FAILED;
+  std::string local_id;
+  base::PostTaskAndReplyWithResult(
+      blocking_task_runner(),
+      FROM_HERE,
+      base::Bind(&internal::ResourceMetadata::AddEntry,
+                 base::Unretained(metadata()),
+                 new_file,
+                 &local_id),
+      google_apis::test_util::CreateCopyResultCallback(&error));
+  test_util::RunBlockingPoolTask();
+  EXPECT_EQ(FILE_ERROR_OK, error);
+
+  // Empty cache file should be returned.
+  base::FilePath cache_file_path;
+  scoped_ptr<ResourceEntry> entry;
+  operation_->EnsureFileDownloadedByPath(
+      file_path,
+      ClientContext(USER_INITIATED),
+      GetFileContentInitializedCallback(),
+      google_apis::GetContentCallback(),
+      google_apis::test_util::CreateCopyResultCallback(
+          &error, &cache_file_path, &entry));
+  test_util::RunBlockingPoolTask();
+  EXPECT_EQ(FILE_ERROR_OK, error);
+
+  int64 cache_file_size = 0;
+  EXPECT_TRUE(base::GetFileSize(cache_file_path, &cache_file_size));
+  EXPECT_EQ(static_cast<int64>(0), cache_file_size);
+  ASSERT_TRUE(entry);
+  EXPECT_EQ(cache_file_size, entry->file_info().size());
+}
+
 }  // namespace file_system
 }  // namespace drive