/// <summary>
/// Helper method to handle decompression of <see cref="WebResponse"/> streams. If the header contains a "Content-Encoding" that is supported by one of
/// the <see cref="Compressors"/>, the returned stream will automatically be decompressed.
/// </summary>
/// <param name="response">Response to process.</param>
/// <returns>Decompressed stream.</returns>
public static Stream Decompress(WebResponse response)
{
IDeCompressor compressor = CheckSupportedCompression(response.Headers.Get("CONTENT-ENCODING"));
Stream responseStream = response.GetResponseStream();
return(compressor == null ? responseStream : Decompress(compressor, responseStream));
}
/// <summary>
/// Helper method to write the contents of <paramref name="inputStream"/> to the <paramref name="response"/> body. Depending on the
/// accepted encodings (<paramref name="acceptEncoding"/> argument), the result will be compressed or not.
/// </summary>
/// <param name="acceptEncoding">The Request's accepted encodings.</param>
/// <param name="response">Response to be written.</param>
/// <param name="inputStream">The input stream the will be written into the Response.</param>
public static async Task WriteCompressedStream(string acceptEncoding, IOwinResponse response, MemoryStream inputStream)
{
IDeCompressor compressor = CheckSupportedCompression(acceptEncoding);
byte[] buffer;
#if !DISABLE_COMPRESSION
if (compressor == null)
{
#endif
buffer = inputStream.ToArray();
response.ContentLength = buffer.Length;
await response.Body.WriteAsync(buffer, 0, buffer.Length);
return;
#if !DISABLE_COMPRESSION
}
#endif
using (MemoryStream compressedStream = (MemoryStream)Compress(compressor, inputStream))
buffer = compressedStream.ToArray();
response.Headers["Content-Encoding"] = compressor.EncodingName;
// If there were multiple methods supported, we need to indicate the varying header.
if (acceptEncoding != compressor.EncodingName)
{
response.Headers["Vary"] = "Accept-Encoding";
}
response.ContentLength = buffer.Length;
await response.Body.WriteAsync(buffer, 0, buffer.Length);
}
/// <summary>
/// Compresses the content of the given <paramref name="inputStream"/> and returns a compressed stream.
/// </summary>
/// <param name="compressor">The <see cref="IDeCompressor"/> to be used.</param>
/// <param name="inputStream">Input Stream to read from. Reading will start from current <see cref="Stream.Position"/>.</param>
/// <returns>Compressed stream.</returns>
private static Stream Compress(IDeCompressor compressor, Stream inputStream)
{
MemoryStream compressed = new MemoryStream();
Stream compressedStream;
using (compressedStream = compressor.CreateCompressionStream(compressed))
{
byte[] buffer = new byte[BUFFER_SIZE];
int nRead;
while ((nRead = inputStream.Read(buffer, 0, buffer.Length)) > 0)
{
compressedStream.Write(buffer, 0, nRead);
}
}
compressed.Position = 0;
return(compressed);
}
/// <summary>
/// Compresses the content of the given <paramref name="inputStream"/> and returns a compressed stream.
/// </summary>
/// <param name="compressor">The <see cref="IDeCompressor"/> to be used.</param>
/// <param name="inputStream">Input Stream to read from. Reading will start from current <see cref="Stream.Position"/>.</param>
/// <returns>Compressed stream.</returns>
private static Stream Compress(IDeCompressor compressor, Stream inputStream)
{
MemoryStream compressed = new MemoryStream();
Stream compressedStream;
using (compressedStream = compressor.CreateCompressionStream(compressed))
{
byte[] buffer = new byte[BUFFER_SIZE];
int nRead;
while ((nRead = inputStream.Read(buffer, 0, buffer.Length)) > 0)
compressedStream.Write(buffer, 0, nRead);
}
compressed.Position = 0;
return compressed;
}
