在 Netty 客户端从 HttpResponse 获取正文字节

如何解决在 Netty 客户端从 HttpResponse 获取正文字节

我正在尝试使用 netty 创建 HTTP 客户端并且一切正常，但是我很难解析正文。我的管道如下所示：

      pipeline.addLast(new HttpClientCodec())
      pipeline.addLast(new HttpContentDecompressor())
      pipeline.addLast(new HttpObjectAggregator(1024*10))
      pipeline.addLast(new HttpClientHandler[A](key,metrics))

和客户端处理程序（用Scala编写）

class HttpClientHandler[A: BodyParser](key: AttributeKey[Callback[A]],metrics: Metrics)
    extends SimpleChannelInboundHandler[FullHttpResponse]
    with LazyLogging {

  override def channelRead0(ctx: ChannelHandlerContext,msg: FullHttpResponse): Unit = {
    val callback = ctx.channel().attr(key).get()
    if (callback != null) {
      val response = buildResponse(msg)
      callback(response)
    } else {
      throw new Exception("Callback not present in channel context ... this is a bug")
    }
  }

  private def buildResponse(msg: FullHttpResponse): Either[Throwable,Response[A]] = {
    val result = {
      try {
        val parsedBody = BodyParser[A].parse(msg.content().asReadOnly())
        if (msg.status() == HttpResponseStatus.OK) {
          Right(Response.Ok(parsedBody))
        } else {
          Right(Response.Other(msg.status().code(),parsedBody))
        }
      } catch {
        case e: Throwable =>
          Left(e)
      }
    }
    result.fold(metrics.bodyParseFailure,metrics.successfulResponse)
    result
  }

  override def exceptionCaught(ctx: ChannelHandlerContext,cause: Throwable): Unit = {
    logger.warn(s"error observed for channel ${ctx.channel()},closing",cause)
    ctx.channel().attr(key).get().apply(Left(cause))
  }

}

主要问题是 msg.content() 还包含 Http 数据（方法、版本、标题...）但我只对正文感兴趣。我究竟做错了什么？谢谢！

解决方法

这太奇怪了... msg.content() 是一个 ByteBuf，它只应该包含请求/响应的有效负载。

,

事实证明这是由于对重复整个 http 请求的回显服务器进行测试引起的，如以下证明：

$ curl -X POST localhost:3000/a/b/c -v
*   Trying ::1...
* TCP_NODELAY set
* Connected to localhost (::1) port 3000 (#0)
> POST /a/b/c HTTP/1.1
> Host: localhost:3000
> User-Agent: curl/7.64.1
> Accept: */*
>
< HTTP/1.1 200 OK
< Date: Sat,19 Dec 2020 09:50:56 GMT
< X-Http-Echo-Server-Id: 9fcf5d57-2ac7-4a92-8aed-775879bf3ac2
< Content-Type: text/plain;charset=utf-8
< Transfer-Encoding: chunked
< Server: Jetty(9.4.24.v20191120)
<
POST /a/b/c HTTP/1.1
Accept: */*
User-Agent: curl/7.64.1
Host: localhost:3000

* Connection #0 to host localhost left intact
* Closing connection 0