[Xpipe-developers] Re: [Xpipe-users] Schedule? XRig implementation? Progammatic invocation of XPipe engine?

[Sean M. <sea...@pr...>]

(I'm cc'ing the developers list as I think Rogers questions are relevant
there - especially how to invoke the current stuff from within a Java=20
program.).


At 08:49 20/02/2002 -0500, Roger L. Costello wrote:
>This is a great technology!  Thanks Sean et al.
>
>Still more questions:
>
>1. The xrigs directory is empty.

Yes :-(

>   When will this get implemented?  I'd
>like to start using this technology (and marketing it to my customers),
>but without XRig I don't see it as being very useful (need branches in
>the pipe for error handling).

Yes. I'm going to get to it as soon as possible but I cannot at this
stage say when it will appear. I'm hoping to make big strides
before end of March but cannot be more specific than that
at this point.


>2. Sean, I looked at your briefing at XML SIG.  It seems to me that
>xcomponents are not consistent with xpipe and xrig.  Consider these
>slides (28, 29, 30):
>
>Major Functional Elements - XComponents
>
>XComponents described in XML form. An XComponent consists of:
>   ...
>   - Code (Java / Jython / XSLT / Exec)
>
>Major Functional Elements =AD XPipes
>
>Described in XML:
>   ...
>   - References to XComponents (URIs) which are resolved when the
>     XPipe is installed/executed
>
>Major Functional Elements =AD XRigs
>
>Described in XML:
>
>   ...
>   - References to XPipes (URIs) which are resolved when the
>     XRig is installed/executed
>
>Notice that XPipes and XRigs provide "references" to the lower level
>component, whereas XComponents "inline" code.  To be consistent,
>shouldn't XComponents "reference" code?  (Then, anything could be an
>XComponent.  A web service could be an XComponent!  Then this technology
>can be used at both a micro and macro level.)

XComponents can contain code so as to make it possible to produce
self-contained XComponents. This is particularly useful for XSLT
components.

The <code> element is missing a href attribute which would allow external
references. This will be fixed in the next release.


>3. I see how to kick off the XPipe engine from a command line.  How do I
>do it from a Java program?

An example of how to do this will be in the next release. In the meantime,=
=20
this works:-

import org.python.util.PythonInterpreter;
import org.python.core.*;

public class ExecuteXPipe {
     public static void main(String []args)
         throws PyException
     {
         PythonInterpreter interp =3D
             new PythonInterpreter();

         interp.exec ("import sys");
         interp.exec ("sys.path.extend=20
(['d:/xpipe','d:/xpipe/undercvs/xpipe/src/jython/src','d:/xpipe/jython/Lib']=
)");
         interp.exec ("from ExecuteXPipe import executeXPipe");
         interp.exec ("executeXPipe ('/foo','in.xml','out.xml','log.xml')");
     }
}


You will need to change the line that is extending the PYTHONPATH so that=20
it includes whatever directories you need.

Then just change the last line to point to wherever you have your XPipe=20
installed, your input/output XML and log file and
you are all set.


>4. Sean, perhaps you could notify this list when/where you will be
>giving a presentation on this technology?  I would have liked to attend
>your XML SIG talk.

Sure. Will do.


>5. I am eager to see the format of how you express <pre> and
><post>-conditions.

High on the list :-)

regards,
Sean