I receive "Cannot create an upload session on a folder" when trying to create upload session

[davidbabayan]

I created a function which is identical to the function described in documentation except I identify the folder where I want to put the file with SharePoint object ID instead of the path.

Here is my function code

    public async Task<DriveItem> UploadFile(string fileName, string folderId, MemoryStream fileContent)
        {
            int maxSliceSize = 320 * 1024;
            long totalLength = fileContent.Length;
            DriveItemUploadableProperties uploadProps = new()
            {
                AdditionalData = new Dictionary<string, object>
                {
                    { "@microsoft.graph.conflictBehavior", "replace" }
                }
            };

            var uploadSession = await GraphServiceClient.Sites[this.SiteId].Drive.Items[folderId]
                                    .CreateUploadSession(uploadProps)
                                    .Request()
                                    .PostAsync();

            LargeFileUploadTask<DriveItem> fileUploadTask = new(uploadSession, fileContent, maxSliceSize);

            IProgress<long> progress = new Progress<long>(prog =>
            {
                Console.WriteLine($"Uploaded {prog} bytes of {totalLength} bytes");
            });

            UploadResult<DriveItem> uploadResult = new();

            try
            {
                uploadResult = await fileUploadTask.UploadAsync(progress);

                Console.WriteLine(uploadResult.UploadSucceeded ?
                    $"Upload complete, item ID: {uploadResult.ItemResponse.Id}" :
                    "Upload failed");
            }
            catch (ServiceException ex)
            {
                Console.WriteLine($"Error uploading: {ex.ToString()}");
            }

            return uploadResult.ItemResponse;
        }

Here is the outcome of the code:

var uploadSession = await GraphServiceClient.Sites[this.SiteId].Drive.Items[folderId]
                                    .CreateUploadSession(uploadProps)
                                    .Request()
                                    .PostAsync();

An unhandled exception occurred while processing the request.
ServiceException: Code: nameAlreadyExists
Message: Cannot create an upload session on a folder
Inner error:
AdditionalData:
date: 2022-05-20T02:37:28
request-id: b7ff5418-47c4-4522-b682-36d8ee435987
client-request-id: b7ff5418-47c4-4522-b682-36d8ee435987
ClientRequestId: b7ff5418-47c4-4522-b682-36d8ee435987

Help me understand what am I doing wrong?

[andrueastman]

Hey @davidbabayan,

Thanks for raising this.

I believe the issue is that you are trying to create an upload session for a folder rather than a file. Any chance you have any luck when you add a segment for a file ItemWithPath("file.txt)" like in the snippet below?

var uploadSession = await graphClient.Sites["site-id"].Drive.Items["folderId"].ItemWithPath("file.txt")
                            .CreateUploadSession(uploadProps)
                            .Request()
                            .PostAsync();

[ghost]

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