如何使用netty通过HTTP流式传输响应(how to stream a response over HTTP with netty)

 我正在使用Netty 3.6.6，我想向调用者发送一个大的响应。 我无法将响应主体复制到ChannelBuffer中，因为在某些情况下它会非常大。 
 
 我正在将服务器从CXF迁移到Netty，以前，我可以使用CXF提供的OutputStream来写入数据。 
 
 我原本试图在没有内容的情况下发送响应，然后继续在一系列8k缓冲区中将数据写入Channel。 这失败了，因为客户端似乎得到了原始响应并且看不到任何数据和抱怨。 我尝试将响应设置为chunked，但这似乎没有区别，也没有设置chunked标头，客户端总是看到一个空流。 
 
 我看到3.6.6的文件服务器示例，这与我想要做的类似，除了数据不是文件。 我看到了ChunkedStream和NioStream，它似乎接近我需要的，除了它们采用InputStream / ReadableByteChannel而我有一个OutputStream; 我可以尝试使用PipedInput和OutputStreams，但这似乎会引入一个不幸的瓶颈。 
 
 我确信有一种方法可以将大量数据流回客户端以响应请求，但我只是没有看到如何操作它，除非我有一个文件。 
 
 我也很好奇如果连接保持活动状态，你是如何让客户知道响应是完整的，并且你是流内容，但不知道内容长度。 似乎客户端会在这些情况下永远等待连接关闭。 
 
 修改3.6.6中的静态文件服务器示例以删除内容长度标头（只是将其注释掉），指定它是一个分块响应 
 
   response.setChunked(true);
   response.setHeader(Names.TRANSFER_ENCODING, Values.CHUNKED);
 
 然后使用ChunkedNioStream在写入响应后发送文件： 
 
    // Write the initial line and the header.
    ch.write(response);

    final ReadableByteChannel aIn = java.nio.channels.Channels.newChannel(new FileInputStream(file));
    ChannelFuture writeFuture = ch.write(new ChunkedNioStream(aIn));
 
 产生不希望的行为，客户端得到几百个字节，然后停止接收，基本上我在我的应用程序中看到的。 正确的事情似乎只发生在内容长度上，这在我的用例中是不可行的。 

I'm using Netty 3.6.6 and I'd like to send a large response back to the caller. I can't copy the response body into a ChannelBuffer as in some cases it will be very large.
 
I'm migrating a server from CXF to Netty, previously, I could just use the OutputStream provided by CXF to write the data. 
 
I originally tried to just send the response without content, and then continued to write data to the Channel in a series of 8k buffers. This failed as the client seemed to get the original response and see no data and complain. I tried setting the response as chunked, but this didnt seem to make a difference, nor did setting the chunked header, the client always saw an empty stream.
 
I saw the file server example for 3.6.6, and that's similar to what I want to do, except the data will not be a file. I saw the ChunkedStream & NioStream, which seemed close to what I need, except they take InputStream/ReadableByteChannel whereas I have an OutputStream; I could try using the PipedInput & OutputStreams, but that seems like it would introduce an unfortunate bottleneck.
 
I'm sure there's a way to stream a lot of data back to the client in response to a request, but I'm just not seeing how to do it unless I have a file.
 
I am also curious how you let the client know the response is complete if the connection is keep-alive, and you're streaming content, but don't know the content length. Seems like the client would wait forever for the connection to close in those cases.
 
Modifying the static file server example from 3.6.6 to remove the content-length header (just comment it out), specify that its a chunked response
 
   response.setChunked(true);
   response.setHeader(Names.TRANSFER_ENCODING, Values.CHUNKED);
 
and then using ChunkedNioStream to send the file after writing the response:
 
    // Write the initial line and the header.
    ch.write(response);

    final ReadableByteChannel aIn = java.nio.channels.Channels.newChannel(new FileInputStream(file));
    ChannelFuture writeFuture = ch.write(new ChunkedNioStream(aIn));
 
Yields the undesired behavior, the client gets a couple hundred bytes and then stop receiving, basically what I'm seeing in my application. The correct thing only seems to happen with a content-length, which is not feasible in my use case.

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