Avoid buffering file download bundles in to memory

2023-08-24 18:31:11 +00:00
parent 83eb274bcb
commit 676c5316f6
3 changed files with 116 additions and 12 deletions
--- a/MareSynchronosServer/MareSynchronosStaticFilesServer/Utils/StreamUtils.cs
+++ b/MareSynchronosServer/MareSynchronosStaticFilesServer/Utils/StreamUtils.cs
@@ -0,0 +1,109 @@
+namespace MareSynchronosStaticFilesServer.Utils;
+
+public class CountedStream : Stream
+{
+    private readonly Stream _stream;
+    public ulong BytesRead { get; private set; }
+    public ulong BytesWritten { get; private set; }
+
+    public CountedStream(Stream underlyingStream)
+    {
+        _stream = underlyingStream;
+    }
+
+    public override bool CanRead => _stream.CanRead;
+
+    public override bool CanSeek => _stream.CanSeek;
+
+    public override bool CanWrite => _stream.CanWrite;
+
+    public override long Length => _stream.Length;
+
+    public override long Position { get => _stream.Position; set => _stream.Position = value; }
+
+    public override void Flush()
+    {
+        _stream.Flush();
+    }
+
+    public override int Read(byte[] buffer, int offset, int count)
+    {
+        int n = _stream.Read(buffer, offset, count);
+        BytesRead += (ulong)n;
+        return n;
+    }
+
+    public override long Seek(long offset, SeekOrigin origin)
+    {
+        return _stream.Seek(offset, origin);
+    }
+
+    public override void SetLength(long value)
+    {
+        _stream.SetLength(value);
+    }
+
+    public override void Write(byte[] buffer, int offset, int count)
+    {
+        BytesWritten += (ulong)count;
+        _stream.Write(buffer, offset, count);
+    }
+}
+
+public class ConcatenatedStreamReader : Stream
+{
+    private IEnumerable<Stream> _streams;
+    private IEnumerator<Stream> _iter;
+    private bool _finished;
+
+    public ConcatenatedStreamReader(IEnumerable<Stream> streams)
+    {
+        _streams = streams;
+        _iter = streams.GetEnumerator();
+        _finished = !_iter.MoveNext();
+    }
+
+    public override bool CanRead => true;
+
+    public override bool CanSeek => false;
+
+    public override bool CanWrite => false;
+
+    public override long Length => throw new NotSupportedException();
+
+    public override long Position { get => throw new NotSupportedException(); set => throw new NotSupportedException(); }
+
+    public override void Flush()
+    {
+    }
+
+    public override int Read(byte[] buffer, int offset, int count)
+    {
+        int n = 0;
+
+        while (n == 0 && !_finished)
+        {
+            n = _iter.Current.Read(buffer, offset, count);
+
+            if (n == 0)
+                _finished = !_iter.MoveNext();
+        }
+
+        return n;
+    }
+
+    public override long Seek(long offset, SeekOrigin origin)
+    {
+        throw new NotSupportedException();
+    }
+
+    public override void SetLength(long value)
+    {
+        throw new NotSupportedException();
+    }
+
+    public override void Write(byte[] buffer, int offset, int count)
+    {
+        throw new NotSupportedException();
+    }
+}