Re: [Xpipe-users] Meaning of the command line parameters of InstallXPipe and ExecuteXPipe? Finding xcomponents?

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

At 10:16 23/02/2002 -0500, Roger L. Costello wrote:
>I have 2 questions:
>
>1. I would like to understand better the meaning of the command line
>parameters to InstallXPipe.py and ExecuteXPipe.py.
>
>In the example described in the README file it gives this example:
>
>jython InstallXPipe.py xp0.xpi testdir
>
>I interpret this command as: "Install the XPipe, xp0.xpi, that is in the
>folder, testdir". Is this a correct interpretation?

The correct interpretation is "install the pipe housed in xp0.xpi into
the directory rooted at testdir".

For executing an XPipe the README file gives this example:

>jython ExecuteXPipe.py xp0.xpi testdir in.xml out.xml log.log


The README says
  jython ExecuteXPipe.py testdir in.xml out.xml log.log

There is no xp0.xpi in the command.

Does this clear it up?


2. In the XPipe, xp0.xpi, it references 3 xcomponents:

><xcomponents>
>         <xcomponentRef href = "xc1.xco">
>                 <doc><p>A null transformation in Java</p></doc>
>                 <parameters></parameters>
>         </xcomponentRef>
>
>         <xcomponentRef href = "xc2.xco">
>                 <doc><p>A null transformation in XSLT</p></doc>
>                 <parameters></parameters>
>         </xcomponentRef>
>
>         <xcomponentRef href = "xc3.xco">
>                 <doc><p>A null transformation in Jython</p></doc>
>                 <parameters></parameters>
>         </xcomponentRef>
>
></xcomponents>
>
>Note the href to each xcomponent, for example: href = "xc1.xco".  When
>the XPipe is Installed:
>
>jython InstallXPipe.py xp0.xpi testdir
>
>the xcomponents are somehow obtained.  This href seems to indicate the
>the xcomponents are in the current folder.  In fact, they are in a
>different folder (../xcomponents).  Shouldn't the href be something like
>this: href="../xcomponents/xc1.xco"?  How did InstallXPipe know how to
>fetch the xcomponents given these hrefs?

The idea is that the hrefs be URIs. In this release XPIPE_HOME environment
variable is used to specify a home directory for XPIPE. The software looks
in this directory + in an xcomponents sub-directory to find
components.


>   It seems that there is some
>implicit understanding by InstallXPipe that the xcomponents will always
>be in the xcomponents folder.


>  Is that true?

Yes.

>   Isn't that bad?

Yes and no. In an ideal world all filesystems would have HTTP interfaces
and we could just use URLs without further thought. We are not
there yet though so XPIPE_HOME trickery is. I think, a worthwhile
feature for now.

regards,
Sean