Logging improvement for HTTP/2

[rstoyanchev]

Currently ReactorNetty formats log messages with the channel id. However for HTTP/2 with multiplexing there needs to be some enhancement, such as also including the stream id, so that log messages can be correlated by request. The same information also needs to be accessible in code that uses Reactor Netty, so that it can format log messages as well.

Related ticket and discussion in the Spring Framework SPR-17507.

[violetagg]

The current (0.8.x releases) logging supported for the HTTP server with HTTP/2 configuration is the following:

16:57:28.201 [reactor-http-nio-2] DEBUG r.n.http.server.HttpServerOperations - [id: 0x790210b8, L:/0:0:0:0:0:0:0:1:8080 - R:/0:0:0:0:0:0:0:1:52050](H2 - 1) New http2 connection, requesting read
16:57:28.208 [reactor-http-nio-2] DEBUG reactor.netty.http.server.HttpServer - [id: 0x790210b8, L:/0:0:0:0:0:0:0:1:8080 - R:/0:0:0:0:0:0:0:1:52050](H2 - 1) Initialized HTTP/2 pipeline Http2MultiplexCodec$DefaultHttp2StreamChannel$1{(HttpServerBind$Http2StreamInitializer#0 = reactor.netty.http.server.HttpServerBind$Http2StreamInitializer), (Http2StreamBridgeHandler#0 = reactor.netty.http.server.Http2StreamBridgeHandler), (Http2StreamFrameToHttpObjectCodec#0 = io.netty.handler.codec.http2.Http2StreamFrameToHttpObjectCodec), (reactor.right.reactiveBridge = reactor.netty.channel.ChannelOperationsHandler)}
16:57:28.290 [reactor-http-nio-2] DEBUG reactor.netty.http.server.HttpServer - [id: 0x790210b8, L:/0:0:0:0:0:0:0:1:8080 - R:/0:0:0:0:0:0:0:1:52050](H2 - 1) Handler is being applied: reactor.netty.http.HttpTests$$Lambda$11/454325163@2569b389

In the handler if you do the following:

.handle((req, res) -> {
        res.withConnection(conn -> System.out.println("CHANNEL long: " + conn.channel().toString() + " short: " + conn.channel().id()));
        return res.sendString(Mono.just("Hello"));
})

You will receive:

CHANNEL long:  [id: 0x790210b8, L:/0:0:0:0:0:0:0:1:8080 - R:/0:0:0:0:0:0:0:1:52050](H2 - 1) short: 790210b8/1

@rstoyanchev Is that what you want?

[rstoyanchev]

@violetagg, sorry for missing this. Yes that seems fine. We currently use channel().id().asShortText() so it seems like it should be a transparent change for us.

[violetagg]

Available since 0.8.x version