From: "Anders Engström" <aengstrom@...>
Date: 2005-02-24T07:03:07+09:00
Subject: Re: Ways of obtaining a remote peer's IP address from distributed ruby?

On Thu, Feb 24, 2005 at 06:44:12AM +0900, Dido Sevilla wrote:
> Is there a way to let a method called via druby over TCP/IP learn the
> IP address of the remote peer invoking it? If not, is there a way to
> allow a local node to obtain its own IP address? I'm writing a program
> that involves having clients connect to a server and register
> addresses where they can be contacted via druby whenever asynchronous
> events later occur.  They will then get called by the server when the
> asynchronous event occurs. DRb.uri gives useless results for this
> application because DRb seems to always use the machine's actual
> hostname in the URI,  which usually doesn't resolve because many of
> the clients have dynamic IP's and don't have valid hostnames as such,
> especially the Windows boxes which run the client.
> 

I had the same question a couple of months ago - and thanks to
#ruby-lang@FreeNode and some code-browsing I found out that the
following should work (in most cases):

    (in a distributed object instance)
    def client_address()
        if client = Thread.current['DRb']['client']
            return client.peeraddr if client.respond_to?(:peeraddr)
        end
    end

DRb binds some useful stuff to the executing thread - but this is very
un-documented :/ I'm not sure how reliable this is from one version to
the next.

//Anders

-- 
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