Null response creating file using Google Drive .NET API - asp.net

Question

I am trying to upload a file onto my Drive using Google Drive .NET API v3. My code is below
static string[] Scopes = { DriveService.Scope.Drive,
DriveService.Scope.DriveAppdata,
DriveService.Scope.DriveFile,
DriveService.Scope.DriveMetadataReadonly,
DriveService.Scope.DriveReadonly,
DriveService.Scope.DriveScripts };
static string ApplicationName = "Drive API .NET Quickstart";
public ActionResult Index()
{
UserCredential credential;
using (var stream =
new FileStream("C:/Users/admin1/Documents/visual studio 2017/Projects/TryGoogleDrive/TryGoogleDrive/client_secret.json", FileMode.Open, FileAccess.Read))
{
string credPath = Environment.GetFolderPath(
System.Environment.SpecialFolder.Personal);
credPath = Path.Combine(credPath, ".credentials/drive-dotnet-quickstart.json");
credential = GoogleWebAuthorizationBroker.AuthorizeAsync(
GoogleClientSecrets.Load(stream).Secrets,
Scopes,
"user",
CancellationToken.None,
new FileDataStore(credPath, true)).Result;
Debug.WriteLine("Credential file saved to: " + credPath);
}
// Create Drive API service.
var service = new DriveService(new BaseClientService.Initializer()
{
HttpClientInitializer = credential,
ApplicationName = ApplicationName,
});
// Define parameters of request.
FilesResource.ListRequest listRequest = service.Files.List();
listRequest.PageSize = 10;
listRequest.Fields = "nextPageToken, files(id, name)";
// List files.
IList<Google.Apis.Drive.v3.Data.File> files = listRequest.Execute()
.Files;
Debug.WriteLine("Files:");
if (files != null && files.Count > 0)
{
foreach (var file in files)
{
Debug.WriteLine("{0} ({1})", file.Name, file.Id);
}
}
else
{
Debug.WriteLine("No files found.");
}
var fileMetadata = new Google.Apis.Drive.v3.Data.File()
{
Name = "report.csv",
MimeType = "text/csv",
};
FilesResource.CreateMediaUpload request;
using (var stream = new FileStream("C:/debugging/report.csv",
FileMode.Open))
{
request = service.Files.Create(
fileMetadata, stream, "text/csv");
request.Fields = "id";
request.Upload();
}
var response = request.ResponseBody;
Console.WriteLine("File ID: " + response.Id);
return View();
}
The problem I'm facing is that response is always null. I looked into it a bit further and found that the request returned a 403 resultCode. I also took a look at some other questions on SO this and this but neither were of any help.
Edit: I forgot to mention that the first part of the code is working correctly - it lists all the files in my Drive. Only the second part is not working (the upload file part)

Answer 1

string[] Scopes = { DriveService.Scope.Drive };
Change the Drive scope then delete the file token.json
in vs2017 you can see token.json file in token.json folder when client_secret.json file present.

Answer 2

Try to visit this post from ASP.NET forum.
The same idea as what you want to do in your app, since you are dealing with uploading a file in Google Drive using .net.
You may try to call rest api directly to achieve your requirement :
The quickstart from .net will help you to make requests from/to the Drive API.
Upload Files:
The Drive API allows you to upload file data when create or
updating a File resource.
You can send upload requests in any of the following ways:
Simple upload: uploadType=media. For quick transfer of a small file (5 MB or less). To perform a simple upload, refer to Performing
a Simple Upload.
Multipart upload: uploadType=multipart. For quick transfer of a small file (5 MB or less) and metadata describing the file, all in a
single request. To perform a multipart upload, refer to Performing a
Multipart Upload.
Resumable upload: uploadType=resumable. For more reliable transfer, especially important with large files. Resumable uploads are
a good choice for most applications, since they also work for small
files at the cost of one additional HTTP request per upload. To
perform a resumable upload, refer to Performing a Resumable
Upload.
You may try this code from the documentation on uploading sample file.
var fileMetadata = new File()
{
Name = "photo.jpg"
};
FilesResource.CreateMediaUpload request;
using (var stream = new System.IO.FileStream("files/photo.jpg",
System.IO.FileMode.Open))
{
request = driveService.Files.Create(
fileMetadata, stream, "image/jpeg");
request.Fields = "id";
request.Upload();
}
var file = request.ResponseBody;
Console.WriteLine("File ID: " + file.Id);
You may check the errors you may encounter in this documentation.

Answer 3

Have a look at what request.Upload() returns. For me when I was having this issue it returned:
Insufficient Permission Errors [Message[Insufficient Permission] Location[ - ]
I changed my scope from DriveService.Scope.DriveReadonly to DriveService.Scope.Drive and I was in business.

Answer 4

Change static string[] Scopes = { DriveService.Scope.DriveReadonly }; to static string[] Scopes = { DriveService.Scope.Drive };.
After changes, take a look into token.json file and check does it change its scope from DriveReadonly to Drive.
If you are seeing DriveReadonly then delete the token.json file and run the application again.