Question

我正在尝试将消息压缩添加到我的WCF服务中，但我有点卡住......

到目前为止，我有：

MessageEncoder的实现：

public class CompressionEncoder : MessageEncoder  
{

    public CompressionEncoderFactory _factory;  
    public const string GZipContentType = "application/x-gzip";

    public override string ContentType
    {
        get
        {
            return GZipContentType;
        }
    }

    public override string MediaType
    {
        get { return ContentType; }
    }

    public override MessageVersion MessageVersion
    {
        get { return _factory.MessageVersion; }
    }

    public CompressionEncoder(CompressionEncoderFactory factory)
    {
        _factory = factory;
    }

    public override Message ReadMessage(Stream stream, int maxSizeOfHeaders,     string contentType)
    {
        var decompressedStream = new GZipStream(stream, System.IO.Compression.CompressionMode.Decompress, false);
        XmlReader reader = XmlReader.Create(decompressedStream);
        Message msg = Message.CreateMessage(reader, maxSizeOfHeaders, _factory.MessageVersion);
        msg.Properties.Encoder = this;
        return msg;
    }

    public override Message ReadMessage(ArraySegment<byte> buffer, BufferManager bufferManager, string contentType)
    {
        MemoryStream stream = new MemoryStream(buffer.Array, buffer.Offset, buffer.Count);
        GZipStream decompressedStream = new GZipStream(stream, System.IO.Compression.CompressionMode.Decompress);
        return ReadMessage(decompressedStream, int.MaxValue);
    }

    public override void WriteMessage(Message message, Stream stream)
    {
        GZipStream compressedStream = new GZipStream(stream, System.IO.Compression.CompressionMode.Compress, true);
        XmlWriter writer = XmlWriter.Create(compressedStream);
        message.WriteMessage(writer);
    }

    public override ArraySegment<byte> WriteMessage(Message message, int maxMessageSize, BufferManager bufferManager, int messageOffset)
    {
        MemoryStream stream = new MemoryStream();
        GZipStream compressedStream = new GZipStream(stream, System.IO.Compression.CompressionMode.Compress, true);
        XmlWriter writer = XmlWriter.Create(compressedStream);
        message.WriteMessage(writer);
        writer.Close();

        int messageLength = (int)compressedStream.Length;
        byte[] messageBytes = new byte[messageLength];
       compressedStream.Read(messageBytes, 0, messageLength);

        int totalLength = messageLength + messageOffset;
        byte[] totalBytes = bufferManager.TakeBuffer(totalLength);
        Array.Copy(messageBytes, 0, totalBytes, messageOffset, messageLength);

        ArraySegment<byte> byteArray = new ArraySegment<byte>(totalBytes, messageOffset, messageLength);
        return byteArray;
    }

}

MessageEncoderFactory的实现：

public class CompressionEncoderFactory : MessageEncoderFactory
{
    CompressionMessageEncodingBindingElement _element;

    public CompressionEncoderFactory(CompressionMessageEncodingBindingElement element)
    {
        _element = element;
    }

    public override MessageEncoder Encoder
    {
        get { return new CompressionEncoder(this); }
    }

    public override MessageVersion MessageVersion
    {
        get { return _element.MessageVersion; }
    }
}

MessageEncodingBindingElement的实现：

public sealed class CompressionMessageEncodingBindingElement : MessageEncodingBindingElement 
{
    MessageVersion _messageVersion = MessageVersion.None;

    public override MessageEncoderFactory CreateMessageEncoderFactory()
    {
        return new CompressionEncoderFactory(this);
    }

    public override MessageVersion MessageVersion
    {
        get
        {
            return _messageVersion;
        }
        set
        {
            _messageVersion = value;
        }
    }

    public override BindingElement Clone()
    {
        return new CompressionMessageEncodingBindingElement();
    }
}

BindingElementExtensionElement的实现：

public class CompressionBindingElementExtensionElement : BindingElementExtensionElement
{
    public override Type BindingElementType
    {
        get { return typeof(CompressionMessageEncodingBindingElement); }
    }

    protected override System.ServiceModel.Channels.BindingElement      CreateBindingElement()
    {
        return new CompressionMessageEncodingBindingElement();
    }
}

在web.config中我添加了这个：

<service name="MyService">
    <endpoint address="" binding="customBinding" bindingConfiguration="CompressionBinding" contract="IMyService" />
    <endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange" />
</service>
...
<bindings>
  <customBinding>
    <binding name="CompressionBinding">
      <messageCompression />
      <httpTransport authenticationScheme="Anonymous"></httpTransport>
    </binding>
  </customBinding>
</bindings>
...
<extensions>
  <bindingElementExtensions>
    <add name="messageCompression" type="MyNamespace.CompressionBindingElementExtensionElement, MyNamespace" />
  </bindingElementExtensions>
</extensions>

但是当我运行客户端并调用一些服务代码时，我收到以下错误：

The message version of the outgoing message (EnvelopeNone (http://schemas.microsoft.com/ws/2005/05/envelope/none) AddressingNone (http://schemas.microsoft.com/ws/2005/05/addressing/none)) does not match that of the encoder (Soap12 (http://www.w3.org/2003/05/soap-envelope) Addressing10 (http://www.w3.org/2005/08/addressing)). Make sure the binding is configured with the same version as the message.

我做错了什么？

Answer 1

尝试在（3.）处更改MessageVersion _messageVersion = MessageVersion.Soap12WSAddressing10;。查看Microsoft技术示例“TechnologySamples \ Extensibility \ MessageEncoder \ Compression \”。

用于消息压缩的WCF绑定扩展

1 个答案: