RE: [docbook] how to throw error if imagedata not found

Ok, here’s a way using Saxon 9:

 

<?xml version="1.0" encoding="UTF-8"?>

<xsl:stylesheet
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"

    xmlns:db="http://docbook.org/ns/docbook"

    xmlns:file="java.io.File"

    version="2.0">

    

    <xsl:template match="db:imagedata">

        <xsl:message><xsl:value-of
select="@fileref"/>: <xsl:value-of
select="file:exists(file:new(resolve-uri(@fileref,
base-uri(.))))"/></xsl:message><!--True if it’s there False if
it’s not -->

    </xsl:template>

    

</xsl:stylesheet>

 

David

 

From: Cramer, David W
(David) [mailto:] 

Sent: Wednesday, October 20, 2010 4:45 PM

To: chris snow

Cc: ; Jim Campbell

Subject: RE: [docbook] how to throw error if imagedata not found

 

Oops..I wasn’t thinking. That will only work if all your images
are svg files…you’ll errors asking it to parse binary files :-)

 

Sorry for the noise, 

David

 

From: Cramer, David W
(David) [mailto:] 

Sent: Wednesday, October 20, 2010 4:13 PM

To: chris snow

Cc: ; Jim Campbell

Subject: RE: [docbook] how to throw error if imagedata not found

 

Hi Chris,

Btw, I ran across a potentially better answer to your question
(depending on the behavior of  your xslt processor): 

http://www.dpawson.co.uk/xsl/sect2/N2602.html#d3859e19

 

David

 

From: Cramer, David W
(David) [mailto:] 

Sent: Wednesday, October 13, 2010 11:42 AM

To: Jim Campbell; chris snow

Cc: 

Subject: RE: [docbook] how to throw error if imagedata not found

 

Hi Chris,

Here’s what we do:

 

The build runs an xslt that produces a list of images used. Ant
then checks to make sure all are the images available and kills with a useful
error message the build if any are missing. To avoid an annoying
build/fail/fix/repeat cycle, the error message shows all missing images rather
than only listing the first missing image it finds.

 

I think to do something like this within the xslt would require
that you write an extension/call out to java. 

 

David

 

From:
 [mailto:] On Behalf Of Jim
Campbell

Sent: Wednesday, October 13, 2010 11:27 AM

To: chris snow

Cc: 

Subject: Re: [docbook] how to throw error if imagedata not found

 

Hi there, Chris,

On Wed, Oct 13, 2010 at 9:16 AM, chris snow <> wrote:

Is it possible for an error to
be thrown during processing if a file

referred to by imagedata is not found?

   <mediaobject>

     <imageobject>

       <imagedata
fileref="../../images/coding-cycle.png"/>

     </imageobject>

   </mediaobject>

Many thanks,

Chris

It might not be exactly what you are looking for, but one
option would be to include the image via an xinclude mechanism, and then
include a xinclude fallback.  It might go something like this:

 

   <mediaobject>

     <imageobject>

       <xi:include
fileref="../../images/coding-cycle.png">

         <xi:fallback>Image file
is unavailable.</xi:fallback>

       </xi:include>

     </imageobject>

   </mediaobject>

 

You would need to use a DTD or schema (or at least a
DTD fragment) that allows for use of xinclude.

 

I hope this helps,

Jim