Deflate with Pako and inflate with asp net core

Question

I'm trying to deflate a .xlsx file on the front end and inflate it in the server side, in a asp net core 2.2 server.

I tried everything and i have this now:

//JS code
handleSaveFile = (file) => {
    var compressedFile = pako.deflate(JSON.stringify(file), { to: 'string' });
    this.setState({ file: compressedFile });
  }

Completely straight forward, pako.deflate is enough to do the trick.

Now on the back-end i tried everything but according to the documentation ends up like this:

I tried also GZipStream, but the result is the same. I cant find anything regarding compress/decompress but there is plenty of info regarding the other way around.

What's the documentation you referred to? It would be better if you share the complete view code that can reproduce the issue(include how to call the server-side method from js). — Xueli Chen, Mar 31 '20 at 05:53
There not much to say, the pako compression is one line of code. Works just fine in the server because i already have it working without compression. What i'm now doing is trying to deflate the body in the server, until now without success. — Júlio Almeida, Apr 04 '20 at 06:06
kinda ignored the situation because my use case doesn't require a file bigger than 25 mb, but eventually will come about. But for sure is not an easy task — Júlio Almeida, Jul 15 '20 at 05:06

score 2 · Answer 1 · answered Mar 27 '21 at 00:05

Please take a look this, hope will help:

Client:

let output = pako.gzip(JSON.stringify(obj));

Server:

public static string Decompress(byte[] data)
{
    // Read the last 4 bytes to get the length
    byte[] lengthBuffer = new byte[4];
    Array.Copy(data, data.Length - 4, lengthBuffer, 0, 4);
    int uncompressedSize = BitConverter.ToInt32(lengthBuffer, 0);

    var buffer = new byte[uncompressedSize];
    using (var ms = new MemoryStream(data))
    {
        using (var gzip = new GZipStream(ms, CompressionMode.Decompress))
        {
            gzip.Read(buffer, 0, uncompressedSize);
        }
    }
    string json = Encoding.UTF8.GetString(buffer); 
    return json;
}

detail in : https://stackoverflow.com/a/66825721/1979406

Deflate with Pako and inflate with asp net core

1 Answers1