ASP .NET Core Web API - Getting and extracting a .zip file from upload controller, using IFormFile

Question

I have an API Upload Controller, which has a parameter IFormFile. From Swagger, I am passing a .zip file which has a few .json files inside. I want to get these .json files from that .zip that I receive from Swagger and pass them to a service that will process them.

So I managed to create a logic like this. I save the .zip file in (~Temp>settings) directory, the next thing I want to do is unzip that file and send the .json files into a different directory named "temp-json-imports". So then I can get the .json files and work with them.

Here is the code that I have written so far, this doesn't work, it fails on the last line - (ZipFile.ExtractToDirectory(filePath, tmpJsonImports);), with an exception of type System.IO.IOException (like shown in the picture below). Any ideas on how can I solve this problem would be very much welcome. :)

[HttpPost("import/{applicationId}")]
public async Task<IActionResult> ImportSettings([FromRoute] Guid applicationId, IFormFile file)
{
    string tempPath = Path.Combine(_hostingEnvironment.ContentRootPath, Path.GetTempPath());
    string tmpSettingsPath = Path.Combine(tempPath, "settings");
    string tmpImportSettings = Path.Combine(tmpSettingsPath, "import");
    string tmpJsonImports = Path.Combine(tmpImportSettings, "temp-json-imports");

    Directory.CreateDirectory(tmpSettingsPath);
    Directory.CreateDirectory(tmpImportSettings);
    Directory.CreateDirectory(tmpJsonImports);

    long size = file.Length;

    if (size > 0)
    {
        var filePath = tmpImportSettings + "\\" + file.FileName;

        using var stream = new FileStream(filePath, FileMode.Create);
        await file.CopyToAsync(stream);

        string zipPath = Path.GetFileName(filePath);
        ZipFile.ExtractToDirectory(filePath, tmpJsonImports);
    }

    return Ok();
}

Answer 1

Try to use your code on my application, it will show this exception:

This exception relates the following code, you didn't close the file handle after copy the file to the path.

    var filePath = tmpImportSettings + "\\" + file.FileName;

    using var stream = new FileStream(filePath, FileMode.Create);
    await file.CopyToAsync(stream);

To solve this exception, try to modify your code as below:

            if (size > 0)
            {
                var filePath = tmpImportSettings + "\\" + fileviewmodel.File.FileName;

                using (var stream = new FileStream(filePath, FileMode.Create))
                {
                    await fileviewmodel.File.CopyToAsync(stream);
                };

                string zipPath = Path.GetFileName(filePath);
                ZipFile.ExtractToDirectory(filePath, tmpJsonImports);
            }