Allow custom ChannelHandlers to control their position

[whiskeysierra]

See zalando/logbook#629. I have a custom netty channel handler that I need to register after the http request decoder/response encoder so that I can observe the request/response as messages in my channel handler.

Plain netty supports this in their HttpServer setup like this:

HttpServer.create()
        .tcpConfiguration(tcpServer ->
                tcpServer.doOnConnection(connection ->
                        connection.addHandlerLast(new LogbookServerHandler(logbook))))

Task List

• Steps to reproduce provided
• Stacktrace (if present) provided
• Example that reproduces the problem uploaded to Github
• Full description of the issue provided (see below)

Steps to Reproduce

1. TODO
2. TODO
3. TODO

Expected Behaviour

Tell us what should happen

Actual Behaviour

Position in the channel pipeline can't be controlled.

Environment Information

• Operating System: TODO
• Micronaut Version: TODO
• JDK Version: TODO

Example Application

• TODO: link to github repository with example that reproduces the issue

[croudet]

I have an HttpServerAccessLogger class, that can help you for the moment:
https://gist.github.com/croudet/52386eb4a315fb7764b83bc12f522db5

[dstepanov]

I think the best idea would be to allow to set custom handlers in HttpClientConfiguration.

[graemerocher]

Relates to #1113

[graemerocher]

Fixed in 2.x and added documentation on how to use logbook https://docs.micronaut.io/snapshot/guide/index.html#nettyPipeline

[dstepanov]

@graemerocher Looks great!
Is it possible to have a separate customizer for server and client?

[graemerocher]

Sure just check the isServerChannel() method