From sean.oriordain at gmail.com  Sun Aug 21 18:46:49 2005
From: sean.oriordain at gmail.com (Sean O'Riordain)
Date: Sun, 21 Aug 2005 17:46:49 +0100
Subject: [Rd] IPC
In-Reply-To: <20050821154001.GC21511@wald.ucdavis.edu>
References: <1124628383.20671.49.camel@schrodinger>
	<8ed68eed05082106117545e667@mail.gmail.com>
	<20050821154001.GC21511@wald.ucdavis.edu>
Message-ID: <8ed68eed05082109462f63e371@mail.gmail.com>

Absolutely - only the simplest of requests with the lowest of
bandwidth requirements should use plain GET requests.

Beyond that you must use some form of detail encapsulation.  SOAP is
layer ontop of HTTP POST requests which is semi-standardized - ie how
a number is encoded is standardized, you still have to code what
parameters are going across the gap at both ends.  There is a lot of
hype about how standard SOAP is... you are still left with a lot of
work to do! :-)

Sometimes it is useful not to have too many dependancies on other
packages or outside software, ie, if you can get away with a simple
GET request in plain R, go for it, but as Duncan says, you need to
beware of character encoding.

s/

On 21/08/05, Duncan Temple Lang <duncan at wald.ucdavis.edu> wrote:
> Sean O'Riordain wrote:
> > for very low bandwidth IPC I'd just use a standard web page form using
> > a GET... so all you have to do is call a URL with the parameters
> > embedded in the URL, e.g.
> >
> > http://silly.name.for.server.com/javaServlet?a=42&b=394&c=1982&d=complex
> >
> > If your bandwidth requirements are a bit higher then you have to start
> > using POST which is a bit more complicated though... so at that stage
> > I might use SOAP.
> 
> POST is not equivalent to SOAP.  SOAP uses POST.
> 
> In order to avoid all the details dealing with HTTP requests
> such as escaping characters, SSL, passwords, POST/GET, etc., it is simplest
> to use something that already takes care of  these.
> The RCurl package (www.omegahat.org/RCurl) is in interface libcurl which takes care of
> so many of these details.  httpRequest (regular CRAN package) is implemented entirely
> within R, but doesn't handle as many of these extra details.
> 
>   D.
> 
> >
> > cheers!
> > Sean
> >
> > On 21/08/05, Nigel Sim <nigel.sim at jcu.edu.au> wrote:
> > > Hi, I need to somehow make R communicate with another remote JAVA
> > > process which provides compute services. I have control over the
> > > communications protocol, but I would like to keep it to a standardised
> > > protocol, such as SOAP, CORBA, etc.
> > >
> > > What I would like to know is, what do other people use to do this? The
> > > nature of the communications will be low bandwidth procedure calls, with
> > > little data. (The data is stored in a DBMS). To date I have tried the
> > > RCORBA and SSOAP packages. Corba I couldn't get to compile, and soap I
> > > couldn't get to talk properly to soapanywhere (the embedded soap
> > > implementation I am trialing).
> > >
> > > I'm sure with persistence I can get both working, but I would like to
> > > hear others experiences before I invest the time.
> > >
> > > Thank you for your time.
> > > --
> > > Nigel Sim
> > >
> > > PhD Candidate
> > > School of Mathematics and Physical Sciences
> > > James Cook University
> > > +61 7 4781 4247
> > > +61 409 277 641
> > >
> > > ______________________________________________
> > > R-devel at r-project.org mailing list
> > > https://stat.ethz.ch/mailman/listinfo/r-devel
> > >
> >
> > ______________________________________________
> > R-devel at r-project.org mailing list
> > https://stat.ethz.ch/mailman/listinfo/r-devel
> 
> --
> Duncan Temple Lang                duncan at wald.ucdavis.edu
> Department of Statistics          work:  (530) 752-4782
> 371 Kerr Hall                     fax:   (530) 752-7099
> One Shields Ave.
> University of California at Davis
> Davis, CA 95616, USA
> 
> 
> 
> 
> 
>



[Rd] IPC
Sean O'Riordain