This is not currently possible in an 'easy' manner. You could do it manually (avoiding the Undertow object and using XNIO + the listeners directly and writing your own code to handle this) however this is probably not what you are after. If you file a JIRA I should be able to get this into the next Undertow version.

Stuart

----- Original Message -----
> From: "Oliver Dain" <oliver@analyticspot.com>
> To: undertow-dev@lists.jboss.org
> Sent: Tuesday, 9 February, 2016 10:27:02 AM
> Subject: [undertow-dev] Let undertow pick a port
>
>
>
> I'm trying to write some unit tests with an embedded undertow server. I’d
> like to have the server find an open port. This makes the tests more robust
> in many ways. For example, tests can be run in parallel and if a socket is
> held in CLOSE_WAIT or something from a previous test the next test will
> still run and succeed. With most servers I’ve used you can pass 0 for the
> port and the server will find an open port. This doesn’t seem to be the case
> with Undertow. Even if that would work, I don't see a method like getPort()
> on the Undertow object so I don't know how I'd discover the port to which it
> bound. Is this possible??
>
>
> Thanks,
> Oliver
> --
> CTO, Analytic Spot
> 44 West Broadway #222
> Eugene, OR 97401
> analyticspot.com • 425-296-6556
> www.linkedin.com/in/oliverdain
>
> _______________________________________________
> undertow-dev mailing list
> undertow-dev@lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/undertow-dev