Listen to unix socket instead of tcp ?

[matthieularere-msq]

Is there currently a way to make prebid-server listen to a unix socket instead of tcp port ? My prebid-server isn't exposed but behind a app acting as a proxy to build the openrtb request send to prebid-server, so using unix socket could avoid me to reach tcp limits.

[bretg]

@matthieularere-msq - can you please elaborate on this request?

• Prebid Server is HTTP, which is TCP.
• Why can't you just raise the TCP limit? Or lower the keepalive?
• Would HTTP2 connection pooling be a solution?

Sounds like you have a server running on the same box and can assume a same-box connection to PBS?

[matthieularere-msq]

Indeed, it's a same-box connection to PBS.
I can try fine tune TCP but at the end the issue could reappear later as a limit would remain. That's why I thought about unix socket.
HTTP2 could worth a try. Apart from using http2 package would it requires a lot of code changes ?

[bretg]

One of the engineers will have to weigh in on whether there's much work to support HTTP2 inbound for PBS-Go and/or PBS-Java. That seems like the easiest approach here, IMO.

[SyntaxNode]

@matthieularere-msq So you are looking to use HTTP over Unix Sockets?

There is not currently an option to listen on Unix Sockets, but I don't see a reason why not to give the Host an option. Are you interested in putting up a PR for this?

I found an example here for how to bind to Unix Sockets in Go. Looks simple. The appropriate place to implement this in PBS-Go is:

prebid-server/server/server.go

Line 96 in 2ac9d20

func newListener(address string, metrics metrics.MetricsEngine) (net.Listener, error) {

You would need to pass the configuration down to those calls (one for admin endpoints and another for the main endpoints). Are you using Prometheus? I haven't looked into how to add Unix Socket support on that endpoint.

I'm also cool with using HTTP2. I think PBS-Go already has support for HTTP2 incoming connections if you'd like to give it a try.

[matthieularere-msq]

@SyntaxNode Thanks, I'll try to see if I manage to make unix socket work, if so I'll submit a PR.

I've tested pbs-go with http2 but it's not supported:

$ curl -I --http2-prior-knowledge http://localhost:8000/openrtb2/auction
curl: (16) Error in the HTTP2 framing layer

[SyntaxNode]

Implemented in PBS-Go 0.208.0 by community contributor @mediasquare-alexandre.

To use this feature, set the unix_socket_enable configuration value to "true" and optionally change the unix_socket_name configuration default value from prebid-server.sock to a value of your choosing. Enabling Unix Sockets will disable the TCP endpoint, as we don't foresee a use case where both would be used.

[SyntaxNode]

@bretg Does PBS-Java plan on adding a similar feature?

[bretg]

Maybe VertX already supports it. Adding @SerhiiNahornyi to confirm

[bretg]

Done in PBS-Java 1.91