MVC/WebApi Stream from HTTPPostedFileBase

Question

I am trying to a pass a stream from a HttpPostedFileBase to a service method without saving to disk.

//Controller Action
[HttpPost]
    public void Import()
    {
        if (Request.Files.Count == 0)
            return new HttpStatusCodeResult(404);

        var file = Request.Files[0];

        _departmentAppService.Import(file.InputStream);
    }

//Service Method
public string Import(Stream stream)
    {
        var excelFile = ExcelFile.Load(stream, LoadOptions.CsvDefault);
        var worksheet = excelFile.Worksheets[0];
        var jsonString = worksheet.ToJsonString();
        return jsonString;
    }

An error of "Property accessor 'ReadTimeout' on object 'System.Web.HttpInputStream' threw the following exception:'Timeouts are not supported on this stream.'" is thrown when the stream is passed to the method. Is there an idiomatic method of doing this?

Answer 1

I was not able to reproduce this issue so I cannot inspect the stack trace that you get, but nevertheless I presume you get timed out because you're processing large CSV file in which case I would try to increase the 'executionTimeout' in web.config.

Also you could try using a temporary memory stream to store an uploaded file, something like the following:

var file = Request.Files[0];
using (var tempStream = new MemoryStream())
{
    file.InputStream.CopyTo(tempStream);
    tempStream.Position = 0;
    _departmentAppService.Import(tempStream);
}

I hope this helps.