Resuming interrupted upload using Google drive v3 C# sdk

Question

I want to resume interrupted resumable upload using Google Drive v3 C# SDK. The reason why I want this is to create resumable upload in Restful Web API. There is google drive api instance in this RestAPI, so this is relaying chunk data from client program to google drive. As you know, client program cannot upload whole file data at one time to Web API, so we need to resume interrupted resumable upload.

So my plan is here.

• First, we need to create upload session and receive Session URI.
• Second, Create Upload instance every time from returned URI and add chunk data.
• Third, repeat 2nd process until EOF.

For this, I made test code, but it does not work at all.

var uploadStream = new System.IO.FileStream(UploadFileName, System.IO.FileMode.Open,
            System.IO.FileAccess.Read);
var insert = service.Files.Create(new Google.Apis.Drive.v3.Data.File { Name = title }, uploadStream, ContentType);

Uri uploadUri = insert.InitiateSessionAsync().Result;

int chunk_size = ResumableUpload.MinimumChunkSize;
while (uploadStream.Length != uploadStream.Position)
{
    byte[] temp = new byte[chunk_size];
    uploadStream.Read(temp, 0, temp.Length);
    MemoryStream stream = new MemoryStream(temp);

    ResumableUpload resume_uploader = ResumableUpload.CreateFromUploadUri(uploadUri, stream);

    resume_uploader.ChunkSize = chunk_size;
    IUploadProgress ss =  resume_uploader.Resume();

    Console.WriteLine("Uploaded " + ss.BytesSent.ToString());
}   

Frankly, I expected to receive 308 Resume Incomplete Code, but the result is different.

"Invalid request. According to the Content-Range header, the final size of the upload is 262144 byte(s). This does not match the expected size of 1193188 byte(s), which was specified in an earlier request."

This means that I need to create code that resumes interrupted resumable upload using Google Drive C# SDK.

Anybody can help me?

Answer 1

Finally, I solved issue. Exact code is below. Actually, I could not find any source code on Google, so I was so sad. Every developer who wants to solve this issue, use my code please. Hope you are fine. :)

    public static async Task<Google.Apis.Drive.v3.Data.File> UploadSync(DriveService driveService, string filepath)
    {
        string destfilename = Path.GetFileName(filepath);

        List<string> parents = new List<string>();

        parents.Add("root");
        // Prepare the JSON metadata
        string json = "{\"name\":\"" + destfilename + "\"";
        if (parents.Count > 0)
        {
            json += ", \"parents\": [";
            foreach (string parent in parents)
            {
                json += "\"" + parent + "\", ";
            }
            json = json.Remove(json.Length - 2) + "]";
        }
        json += "}";
        Debug.WriteLine(json);

        Google.Apis.Drive.v3.Data.File uploadedFile = null;
        try
        {
            System.IO.FileInfo info = new System.IO.FileInfo(filepath);

            ulong fileSize = (ulong)info.Length;

            var uploadStream = new System.IO.FileStream(filepath, System.IO.FileMode.Open, System.IO.FileAccess.Read);

            var insert = driveService.Files.Create(new Google.Apis.Drive.v3.Data.File { Name = destfilename, Parents = new List<string> { "root" } }, uploadStream, "application/octet-stream");

            Uri uploadUri = insert.InitiateSessionAsync().Result;

            int chunk_size = ResumableUpload.MinimumChunkSize;
            int bytesSent = 0;
            while (uploadStream.Length != uploadStream.Position)
            {
                byte[] temp = new byte[chunk_size];
                int cnt = uploadStream.Read(temp, 0, temp.Length);
                if (cnt == 0)
                    break;

                HttpWebRequest httpRequest = (HttpWebRequest)WebRequest.Create(uploadUri);

                httpRequest.Method = "PUT";
                httpRequest.Headers["Authorization"] = "Bearer " + ((UserCredential)driveService.HttpClientInitializer).Token.AccessToken;
                httpRequest.ContentLength = (long)cnt;
                httpRequest.Headers["Content-Range"] = string.Format("bytes {0}-{1}/{2}", bytesSent, bytesSent + cnt - 1, fileSize);

                using (System.IO.Stream requestStream = httpRequest.GetRequestStreamAsync().Result)
                {
                    requestStream.Write(temp, 0, cnt);
                }

                HttpWebResponse httpResponse;
                try
                {
                    httpResponse = (HttpWebResponse)httpRequest.GetResponse();
                }
                catch (WebException ex)
                {
                    httpResponse = (HttpWebResponse)ex.Response;
                }

                if (httpResponse.StatusCode == HttpStatusCode.OK)
                { }
                else if ((int)httpResponse.StatusCode != 308)
                    break;

                bytesSent += cnt;

                Console.WriteLine("Uploaded " + bytesSent.ToString());
            }

            if (bytesSent != uploadStream.Length)
            {
                return null;
            }

            // Try to retrieve the file from Google
            FilesResource.ListRequest request = driveService.Files.List();
            if (parents.Count > 0)
                request.Q += "'" + parents[0] + "' in parents and ";
            request.Q += "name = '" + destfilename + "'";
            FileList result = request.Execute();
            if (result.Files.Count > 0)
                uploadedFile = result.Files[0];
        }
        catch (Exception ex)
        {
            Debug.WriteLine(ex.Message);
        }

        return uploadedFile;
    }