ngx_stream_pass_module: add an option to allow keeping the incoming stream server_port

[linsite]

Describe the feature you'd like to add to nginx

With ngx_stream_pass_module, one can pass a connection directly from stream to a http server. For now, the passed connection into http context will see the http server_port instead of the real incoming stream server_port.

When a HTTP request can come from both the http server and stream server, one may want see the incoming stream server_port, so one can tell where the request is coming from.

Describe the problem this feature solves

For now there is no such option. Connections' local_addr is forced to set to the http server listening address.

Additional context

A simple boolean option can be added to pass directive.

[arut]

Indeed the target sockaddr is set to the connection before passing. This is viewed as a feature since the connection looks like a native connection at the destination. Currently it seems like there's no way to tell if the connection has been passed from another port, except if it's passed to a special port. I'll think about a way to tell that. It can be a directive to keep the original port, or for example a variable is_passed.

[linsite]

Indeed the target sockaddr is set to the connection before passing. This is viewed as a feature since the connection looks like a native connection at the destination. Currently it seems like there's no way to tell if the connection has been passed from another port, except if it's passed to a special port. I'll think about a way to tell that. It can be a directive to keep the original port, or for example a variable is_passed.

Thanks for your reply, Roman. I'm available for those tests, please let me know if needed.