Files.app: Add an private API to get a download URL

chrome/browser/drive/drive_api_service.cc

 // Copyright (c) 2012 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.
 
 #include "chrome/browser/drive/drive_api_service.h"
 
 #include <string>
 #include <vector>
 
 #include "base/bind.h"
@@ skipping 26 matching lines @@
 using google_apis::EntryActionCallback;
 using google_apis::FileList;
 using google_apis::FileListCallback;
 using google_apis::FileResource;
 using google_apis::FileResourceCallback;
 using google_apis::GDATA_OTHER_ERROR;
 using google_apis::GDATA_PARSE_ERROR;
 using google_apis::GDataErrorCode;
 using google_apis::GetContentCallback;
 using google_apis::GetResourceEntryRequest;
-using google_apis::GetShareUrlCallback;
+using google_apis::GetUrlCallback;
 using google_apis::HTTP_NOT_IMPLEMENTED;
 using google_apis::HTTP_SUCCESS;
 using google_apis::InitiateUploadCallback;
 using google_apis::Link;
 using google_apis::ProgressCallback;
 using google_apis::RequestSender;
 using google_apis::UploadRangeResponse;
 using google_apis::drive::AboutGetRequest;
 using google_apis::drive::AppsListRequest;
 using google_apis::drive::ChangesListRequest;
@@ skipping 36 matching lines @@
 // only the total time matters. However, the server seems to have a time limit
 // per single request, which disables us to set the largest value (1000).
 // TODO(kinaba): make it larger when the server gets faster.
 const int kMaxNumFilesResourcePerRequest = 300;
 const int kMaxNumFilesResourcePerRequestForSearch = 100;
 
 // For performance, we declare all fields we use.
 const char kAboutResourceFields[] =
     "kind,quotaBytesTotal,quotaBytesUsed,largestChangeId,rootFolderId";
 const char kFileResourceFields[] =
-    "kind,id,title,createdDate,sharedWithMeDate,mimeType,"
+    "kind,id,title,createdDate,sharedWithMeDate,downloadUrl,mimeType,"
     "md5Checksum,fileSize,labels/trashed,imageMediaMetadata/width,"
     "imageMediaMetadata/height,imageMediaMetadata/rotation,etag,"
     "parents(id,parentLink),alternateLink,"
     "modifiedDate,lastViewedByMeDate,shared";
 const char kFileResourceOpenWithLinksFields[] =
     "kind,id,openWithLinks/*";
 const char kFileListFields[] =
-    "kind,items(kind,id,title,createdDate,sharedWithMeDate,"
+    "kind,items(kind,id,title,createdDate,sharedWithMeDate,downloadUrl,"

[kinaba, 2014/07/09 06:02:48]

If we don't store downloadUrl in ResourceMetadata DB,
I think we can omit including the field in FileList and ChangeList.

Well, but on the other hand, if this inclusion does not affect performance, we
should not add divergence. @hashimoto, do you have any thoughts?

[hashimoto, 2014/07/09 07:48:57]

When last time I investigated this, "downloadUrl" was one of the "slow" fields
which makes the request about 50% slower.

But today it seems "downloadUrl" does not affect the performance much.
https://docs.google.com/spreadsheets/d/1Gi2NcoTkTfNjY8HYSuAjVZPj3BKTXkki2y4yI...

Getting a FileList with 300 entries takes 1.7 seconds both with and without
"downloadUrl".
Maybe the Drive server implementation has improved since then?

     "mimeType,md5Checksum,fileSize,labels/trashed,imageMediaMetadata/width,"
     "imageMediaMetadata/height,imageMediaMetadata/rotation,etag,"
     "parents(id,parentLink),alternateLink,"
     "modifiedDate,lastViewedByMeDate,shared),nextLink";
 const char kChangeListFields[] =
-    "kind,items(file(kind,id,title,createdDate,sharedWithMeDate,"
+    "kind,items(file(kind,id,title,createdDate,sharedWithMeDate,downloadUrl,"

[kinaba, 2014/07/09 06:02:48]

ditto

     "mimeType,md5Checksum,fileSize,labels/trashed,imageMediaMetadata/width,"
     "imageMediaMetadata/height,imageMediaMetadata/rotation,etag,"
     "parents(id,parentLink),alternateLink,modifiedDate,"
     "lastViewedByMeDate,shared),deleted,id,fileId,modificationDate),nextLink,"
     "largestChangeId";
 
 void ExtractOpenUrlAndRun(const std::string& app_id,
                           const AuthorizeAppCallback& callback,
                           GDataErrorCode error,
                           scoped_ptr<FileResource> value) {
@@ skipping 224 matching lines @@
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(!callback.is_null());
 
   FilesGetRequest* request = new FilesGetRequest(
       sender_.get(), url_generator_, callback);
   request->set_file_id(resource_id);
   request->set_fields(kFileResourceFields);
   return sender_->StartRequestWithRetry(request);
 }
 
-CancelCallback DriveAPIService::GetShareUrl(
-    const std::string& resource_id,
-    const GURL& embed_origin,
-    const GetShareUrlCallback& callback) {
+CancelCallback DriveAPIService::GetShareUrl(const std::string& resource_id,
+                                            const GURL& embed_origin,
+                                            const GetUrlCallback& callback) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(!callback.is_null());
 
   // Unfortunately "share url" is not yet supported on Drive API v2.
   // So, as a fallback, we use GData WAPI protocol for this method.
   // TODO(hidehiko): Get rid of this implementation when share url is
   // supported on Drive API v2.
   return sender_->StartRequestWithRetry(
       new GetResourceEntryRequest(sender_.get(),
                                   wapi_url_generator_,
@@ skipping 373 matching lines @@
   if (CanSendRequest()) {
     FOR_EACH_OBSERVER(
         DriveServiceObserver, observers_, OnReadyToSendRequests());
   } else if (!HasRefreshToken()) {
     FOR_EACH_OBSERVER(
         DriveServiceObserver, observers_, OnRefreshTokenInvalid());
   }
 }
 
 }  // namespace drive