How to download/upload files using RestEase with ASP.NET Web API?

[shabakett]

Please add examples to README illustrating how to use RestEase with ASP.NET Web API to download/upload files of any type (application/octet-stream) just by providing the file path as parameter.

[canton7]

There's nothing built in which will take a filename ad a parameter. However you can quite easily just pass a Stream, see here in the README.

Likewise downloading a file - return a Stream (or HttpResponseMessage if you need to access the response headers as well), and copy that to a FileStream.

[shabakett]

what about this method (ASP.NET side)?

[HttpGet("download")]
public async Task<ActionResult> DownloadFile(string path)
{    
    var bytes = await System.IO.File.ReadAllBytesAsync(path);
    return File(bytes, "application/octet-stream");
}

[canton7]

Something simple like this?

Return a Stream, and copy that to a FileStream.

public interface ISomeApi
{
    Task<Stream> DownloadAsync([Query] string path);
}

using var response = await api.DownloadAsync(...);
using var fs = File.Create(...);
await response.CopyToAsync(fs);

[shabakett]

this works for me

// RestEase
[Get("download")]
Task<Stream> DownloadAsync(string path);

[Post("upload")]
[Header("Content-Type", "application/octet-stream")]
Task UploadAsync(string path, [Body] Stream stream);

// ASP.NET

[HttpGet, Route("download")]
public Task<Stream> DownloadAsync(string path) => Task.Run(() => (Stream)new FileStream(path, FileMode.Open));

[HttpPost, Route("upload")]
[Consumes("application/octet-stream")]
public async Task UploadAsync(string path, [FromBody] Stream stream)
{
	using var savedFileStream = new FileStream(path, FileMode.Create);
	await stream.CopyToAsync(savedFileStream);
}

public class Startup
{
	public void ConfigureServices(IServiceCollection services)
	{
		services.AddControllers(options => options.InputFormatters.Add(new InputFormatterStream()));
	}
}

public class InputFormatterStream : InputFormatter
{
	public InputFormatterStream() => SupportedMediaTypes.Add(MediaTypeHeaderValue.Parse("application/octet-stream"));
	protected override bool CanReadType(Type type) => type == typeof(Stream);
	public override Task<InputFormatterResult> ReadRequestBodyAsync(InputFormatterContext context) => InputFormatterResult.SuccessAsync(context.HttpContext.Request.Body);
}

// download usage
using var downloadedStream = await DownloadAsync(@"\remote\path\file.bin");
using var savedFileStream = new FileStream(@"\local\path\file.bin", FileMode.Create);
await downloadedStream.CopyToAsync(savedFileStream);

// upload usage
using var fileStream = File.OpenRead(@"\local\path\file.bin");
await UploadAsync(@"\remote\path\file.bin", fileStream);

[canton7]

Cool. Bear in mind that letting a remote user overwrite any file on the file system is a huge security hole!