Compile Brotli into a DLL .NET can reference

Question

So I'd like to take advantage of Brotli but I am not familiar with Python and C++..

I know someone had compiled it into a Windows .exe. But how do I wrap it into a DLL or something that a .NET app can reference? I know there's IronPython, do I just bring in all the source files into an IronPython project and write a .NET adapter that calls into the Brotli API and exposes them? But actually, I'm not even sure if the Brotli API is Python or C++..

Looking at tools/bro.cc, it looks like the "entry" methods are defined in encode.c and decode.c as BrotliCompress(), BrotliDecompressBuffer(), BrotliDecompressStream() methods. So I suppose a DLL can be compiled from the C++ classes.

Answer 1

You may use Brotli.NET which provides full stream support.

1. github: https://github.com/XieJJ99/brotli.net/.
2. Nuget: https://www.nuget.org/packages/Brotli.NET/.

To compress a stream to brotli data:

   public Byte[] Encode(Byte[] input)
   {
       Byte[] output = null;
       using (System.IO.MemoryStream msInput = new System.IO.MemoryStream(input))
       using (System.IO.MemoryStream msOutput = new System.IO.MemoryStream())
       using (BrotliStream bs = new BrotliStream(msOutput, System.IO.Compression.CompressionMode.Compress))
       {
           bs.SetQuality(11);
           bs.SetWindow(22);
           msInput.CopyTo(bs);
           bs.Close();
           output = msOutput.ToArray();
           return output;
       }
   }

To decompress a brotli stream:

   public Byte[] Decode(Byte[] input)
   {
       using (System.IO.MemoryStream msInput = new System.IO.MemoryStream(input))
       using (BrotliStream bs = new BrotliStream(msInput, System.IO.Compression.CompressionMode.Decompress))
       using (System.IO.MemoryStream msOutput = new System.IO.MemoryStream())
       {
           bs.CopyTo(msOutput);
           msOutput.Seek(0, System.IO.SeekOrigin.Begin);
           output = msOutput.ToArray();
           return output;
       }

   }

To support dynamic compress in web applications,add the code like this in the Global.asax.cs:

    protected void Application_PostAcquireRequestState(object sender, EventArgs e)
    {
                       var app = Context.ApplicationInstance;
            String acceptEncodings = app.Request.Headers.Get("Accept-Encoding");

            if (!String.IsNullOrEmpty(acceptEncodings))
            {
                System.IO.Stream baseStream = app.Response.Filter;
                acceptEncodings = acceptEncodings.ToLower();

                if (acceptEncodings.Contains("br") || acceptEncodings.Contains("brotli"))
                {
                    app.Response.Filter = new Brotli.BrotliStream(baseStream, System.IO.Compression.CompressionMode.Compress);
                    app.Response.AppendHeader("Content-Encoding", "br");
                }
                else
                if (acceptEncodings.Contains("deflate"))
                {
                    app.Response.Filter = new System.IO.Compression.DeflateStream(baseStream, System.IO.Compression.CompressionMode.Compress);
                    app.Response.AppendHeader("Content-Encoding", "deflate");
                }
                else if (acceptEncodings.Contains("gzip"))
                {
                    app.Response.Filter = new System.IO.Compression.GZipStream(baseStream, System.IO.Compression.CompressionMode.Compress);
                    app.Response.AppendHeader("Content-Encoding", "gzip");
                }

            }
       }