我需要在由顺序发送->接收->发送->接收并返回最后一个接收值的TCP连接中执行自定义握手，但是我在链接执行时遇到问题。
这是我所拥有的：
DisposableServer server = TcpServer.create()
.host("localhost")
.port(4059)
.wiretap(true)
.handle((nettyInbound, nettyOutbound) ->
nettyInbound.receive().asByteArray().flatMap(bytes -> {
log.info("Server inbound: {}", bytes);
if (Arrays.equals(bytes, new byte[]{1, 2, 3})) {
nettyOutbound.sendByteArray(Mono.just(new byte[]{7, 6, 5})).then().subscribe();
} else if (Arrays.equals(bytes, new byte[]{5, 6, 7})) {
nettyOutbound.sendByteArray(Mono.just(new byte[]{9, 8, 7})).then().subscribe();
}
return Mono.empty();
}))
.bindNow();
TcpClient.create()
.host("localhost")
.port(4059)
.option(ChannelOption.CONNECT_TIMEOUT_MILLIS, 3000)
.wiretap(true)
.connect()
.flatMap(connection ->
connection.outbound().sendByteArray(Mono.just(new byte[]{1, 2, 3}))
.then(connection.inbound().receive().asByteArray().next().flatMap(bytes -> {
log.info("bytes {}", bytes);
return Mono.empty();
})).sendByteArray(Mono.just(new byte[]{5, 6, 7}))
.then(connection.inbound().receive().asByteArray().next().flatMap(bytes -> {
log.info("bytes {}", bytes);
return Mono.empty();
}))
.then()
)
.subscribe();
server.onDispose().block();
最大的问题是TcpClient的第二个receive的{{1}}未执行，并且在日志中flatMap正确地显示了已读取但未读取的数据发射到该wiretap。
日志还显示客户端发送了多个相同的消息：
flatMap有人可以向我指出正确的方向，如何正确链接14:25:04.394 [reactor-tcp-nio-2] DEBUG reactor.netty.tcp.TcpClient - [id: 0x3d2ab8be, L:/127.0.0.1:52044 - R:localhost/127.0.0.1:4059] WRITE: 3B
+-------------------------------------------------+
| 0 1 2 3 4 5 6 7 8 9 a b c d e f |
+--------+-------------------------------------------------+----------------+
|00000000| 01 02 03 |... |
+--------+-------------------------------------------------+----------------+
14:25:04.480 [reactor-tcp-nio-2] DEBUG reactor.netty.tcp.TcpClient - [id: 0x3d2ab8be, L:/127.0.0.1:52044 - R:localhost/127.0.0.1:4059] FLUSH
14:25:04.509 [reactor-tcp-nio-2] DEBUG reactor.netty.channel.FluxReceive - [id: 0x3d2ab8be, L:/127.0.0.1:52044 - R:localhost/127.0.0.1:4059] Subscribing inbound receiver [pending: 0, cancelled:false, inboundDone: false]
14:25:04.525 [reactor-tcp-nio-3] DEBUG reactor.netty.tcp.TcpServer - [id: 0xf6dd2f6d, L:/127.0.0.1:4059 - R:/127.0.0.1:52044] READ: 3B
+-------------------------------------------------+
| 0 1 2 3 4 5 6 7 8 9 a b c d e f |
+--------+-------------------------------------------------+----------------+
|00000000| 01 02 03 |... |
+--------+-------------------------------------------------+----------------+
14:25:04.527 [reactor-tcp-nio-3] INFO hr.omega.software.iot.adapter.dlmsadapter.test.DlmsTest - Server inbound: [1, 2, 3]
14:25:04.528 [reactor-tcp-nio-3] DEBUG reactor.netty.tcp.TcpServer - [id: 0xf6dd2f6d, L:/127.0.0.1:4059 - R:/127.0.0.1:52044] WRITE: 3B
+-------------------------------------------------+
| 0 1 2 3 4 5 6 7 8 9 a b c d e f |
+--------+-------------------------------------------------+----------------+
|00000000| 07 06 05 |... |
+--------+-------------------------------------------------+----------------+
14:25:04.528 [reactor-tcp-nio-3] DEBUG reactor.netty.tcp.TcpServer - [id: 0xf6dd2f6d, L:/127.0.0.1:4059 - R:/127.0.0.1:52044] FLUSH
14:25:04.529 [reactor-tcp-nio-3] DEBUG reactor.netty.tcp.TcpServer - [id: 0xf6dd2f6d, L:/127.0.0.1:4059 - R:/127.0.0.1:52044] READ COMPLETE
14:25:04.529 [reactor-tcp-nio-2] DEBUG reactor.netty.tcp.TcpClient - [id: 0x3d2ab8be, L:/127.0.0.1:52044 - R:localhost/127.0.0.1:4059] READ: 3B
+-------------------------------------------------+
| 0 1 2 3 4 5 6 7 8 9 a b c d e f |
+--------+-------------------------------------------------+----------------+
|00000000| 07 06 05 |... |
+--------+-------------------------------------------------+----------------+
14:25:04.530 [reactor-tcp-nio-2] INFO hr.omega.software.iot.adapter.dlmsadapter.test.DlmsTest - bytes [7, 6, 5]
14:25:04.531 [reactor-tcp-nio-2] DEBUG reactor.netty.tcp.TcpClient - [id: 0x3d2ab8be, L:/127.0.0.1:52044 - R:localhost/127.0.0.1:4059] WRITE: 3B
+-------------------------------------------------+
| 0 1 2 3 4 5 6 7 8 9 a b c d e f |
+--------+-------------------------------------------------+----------------+
|00000000| 01 02 03 |... |
+--------+-------------------------------------------------+----------------+
14:25:04.536 [reactor-tcp-nio-2] DEBUG reactor.netty.tcp.TcpClient - [id: 0x3d2ab8be, L:/127.0.0.1:52044 - R:localhost/127.0.0.1:4059] FLUSH
14:25:04.536 [reactor-tcp-nio-2] DEBUG reactor.netty.tcp.TcpClient - [id: 0x3d2ab8be, L:/127.0.0.1:52044 - R:localhost/127.0.0.1:4059] WRITE: 3B
+-------------------------------------------------+
| 0 1 2 3 4 5 6 7 8 9 a b c d e f |
+--------+-------------------------------------------------+----------------+
|00000000| 05 06 07 |... |
+--------+-------------------------------------------------+----------------+
14:25:04.536 [reactor-tcp-nio-3] DEBUG reactor.netty.tcp.TcpServer - [id: 0xf6dd2f6d, L:/127.0.0.1:4059 - R:/127.0.0.1:52044] READ: 3B
+-------------------------------------------------+
| 0 1 2 3 4 5 6 7 8 9 a b c d e f |
+--------+-------------------------------------------------+----------------+
|00000000| 01 02 03 |... |
+--------+-------------------------------------------------+----------------+
14:25:04.536 [reactor-tcp-nio-2] DEBUG reactor.netty.tcp.TcpClient - [id: 0x3d2ab8be, L:/127.0.0.1:52044 - R:localhost/127.0.0.1:4059] FLUSH
14:25:04.536 [reactor-tcp-nio-3] INFO hr.omega.software.iot.adapter.dlmsadapter.test.DlmsTest - Server inbound: [1, 2, 3]
14:25:04.536 [reactor-tcp-nio-3] DEBUG reactor.netty.tcp.TcpServer - [id: 0xf6dd2f6d, L:/127.0.0.1:4059 - R:/127.0.0.1:52044] WRITE: 3B
+-------------------------------------------------+
| 0 1 2 3 4 5 6 7 8 9 a b c d e f |
+--------+-------------------------------------------------+----------------+
|00000000| 07 06 05 |... |
+--------+-------------------------------------------------+----------------+
14:25:04.537 [reactor-tcp-nio-2] DEBUG reactor.netty.channel.FluxReceive - [id: 0x3d2ab8be, L:/127.0.0.1:52044 - R:localhost/127.0.0.1:4059] Subscribing inbound receiver [pending: 0, cancelled:true, inboundDone: false]
14:25:04.537 [reactor-tcp-nio-2] DEBUG reactor.netty.tcp.TcpClient - [id: 0x3d2ab8be, L:/127.0.0.1:52044 - R:localhost/127.0.0.1:4059] READ COMPLETE
14:25:04.537 [reactor-tcp-nio-3] DEBUG reactor.netty.tcp.TcpServer - [id: 0xf6dd2f6d, L:/127.0.0.1:4059 - R:/127.0.0.1:52044] FLUSH
14:25:04.537 [reactor-tcp-nio-3] DEBUG reactor.netty.tcp.TcpServer - [id: 0xf6dd2f6d, L:/127.0.0.1:4059 - R:/127.0.0.1:52044] READ COMPLETE
14:25:04.537 [reactor-tcp-nio-2] DEBUG reactor.netty.tcp.TcpClient - [id: 0x3d2ab8be, L:/127.0.0.1:52044 - R:localhost/127.0.0.1:4059] READ: 3B
+-------------------------------------------------+
| 0 1 2 3 4 5 6 7 8 9 a b c d e f |
+--------+-------------------------------------------------+----------------+
|00000000| 07 06 05 |... |
+--------+-------------------------------------------------+----------------+
14:25:04.537 [reactor-tcp-nio-3] DEBUG reactor.netty.tcp.TcpServer - [id: 0xf6dd2f6d, L:/127.0.0.1:4059 - R:/127.0.0.1:52044] READ: 3B
+-------------------------------------------------+
| 0 1 2 3 4 5 6 7 8 9 a b c d e f |
+--------+-------------------------------------------------+----------------+
|00000000| 05 06 07 |... |
+--------+-------------------------------------------------+----------------+
14:25:04.538 [reactor-tcp-nio-3] INFO hr.omega.software.iot.adapter.dlmsadapter.test.DlmsTest - Server inbound: [5, 6, 7]
14:25:04.538 [reactor-tcp-nio-3] DEBUG reactor.netty.tcp.TcpServer - [id: 0xf6dd2f6d, L:/127.0.0.1:4059 - R:/127.0.0.1:52044] WRITE: 3B
+-------------------------------------------------+
| 0 1 2 3 4 5 6 7 8 9 a b c d e f |
+--------+-------------------------------------------------+----------------+
|00000000| 09 08 07 |... |
+--------+-------------------------------------------------+----------------+
14:25:04.538 [reactor-tcp-nio-3] DEBUG reactor.netty.tcp.TcpServer - [id: 0xf6dd2f6d, L:/127.0.0.1:4059 - R:/127.0.0.1:52044] FLUSH
14:25:04.538 [reactor-tcp-nio-2] DEBUG reactor.netty.channel.FluxReceive - [id: 0x3d2ab8be, L:/127.0.0.1:52044 - R:localhost/127.0.0.1:4059] Dropping frame PooledUnsafeDirectByteBuf(ridx: 0, widx: 3, cap: 1024), 0 in buffer
14:25:04.539 [reactor-tcp-nio-2] DEBUG reactor.netty.tcp.TcpClient - [id: 0x3d2ab8be, L:/127.0.0.1:52044 - R:localhost/127.0.0.1:4059] READ COMPLETE
14:25:04.539 [reactor-tcp-nio-3] DEBUG reactor.netty.tcp.TcpServer - [id: 0xf6dd2f6d, L:/127.0.0.1:4059 - R:/127.0.0.1:52044] READ COMPLETE
14:25:04.539 [reactor-tcp-nio-2] DEBUG reactor.netty.tcp.TcpClient - [id: 0x3d2ab8be, L:/127.0.0.1:52044 - R:localhost/127.0.0.1:4059] READ: 3B
+-------------------------------------------------+
| 0 1 2 3 4 5 6 7 8 9 a b c d e f |
+--------+-------------------------------------------------+----------------+
|00000000| 09 08 07 |... |
+--------+-------------------------------------------------+----------------+
14:25:04.539 [reactor-tcp-nio-2] DEBUG reactor.netty.channel.FluxReceive - [id: 0x3d2ab8be, L:/127.0.0.1:52044 - R:localhost/127.0.0.1:4059] Dropping frame PooledUnsafeDirectByteBuf(ridx: 0, widx: 3, cap: 512), 0 in buffer
14:25:04.539 [reactor-tcp-nio-2] DEBUG reactor.netty.tcp.TcpClient - [id: 0x3d2ab8be, L:/127.0.0.1:52044 - R:localhost/127.0.0.1:4059] READ COMPLETE
TcpClient-> send-> receive-> send，并返回最后一个获得价值？
答案 0 :(得分：1)
弄清楚了。问题中的解决方案不起作用的原因是，您不能调用connection.inbound().receive()两次，而只能调用一次，因此必须在该调用中处理整个通信流程。
我写了一篇具有正确解决方案的文章：How to Implement a Custom Handshaking Protocol via TCP Using Reactor Netty