Re: XSLT-accessed query params and testing existance
On onsdag 7. juli 2004, 18:41, Michael A Nachbaur wrote: But then, I need to test whether a parameter exists... In XSP that's straightforward, thanks to the many good taglibs, but I haven't found anything on checking the parameters in XSLT, is it doable? Well, the most common method I know of doing that is: xsl:param name=foo select=''/ Is that line really necessary? xsl:if test=$foo = '' !-- Test to see if no value has been supplied -- /xsl:if xsl:if test=not($foo = '') !-- Test to see if a value has been supplied -- /xsl:if Yhm, yes of course... The reason why I first thought this was inadequate was that it checks for an empty string rather than a non-existant variable. Which would make a situation where I want to delete a string harder to work with. But since you say it, of course, the query parameters are not making that distinction, a parameter is passed on from a request even if the field wasn't given a value. Which means I would have to work around the around problem anyway. So thanks! You can probably clean this up a bit by using named templates. xsl:template name=param.foo xsl:choose xsl:when test=$foo = '' xsl:value-of select=$foo/ /xsl:when xsl:otherwise xsl:value-of select=foo/ /xsl:otherwise /xsl:choose /xsl:template Yup, nice! Is there more documentation on the parameters AxKit pass to XSLT somewhere now? I remembered an old thread about them and found it in the archives, but that was about all. IIRC, by default it adds the query string parameters supplied to the URL, and any additional parameters added by any AxKit plugins that are supplied. For instance, you can use one of the Apache::AxKit::Plugin::AddXSLParams::* modules to put in additional parameters as needed. Yup, but things like if a xsl:param name=foo select=''/ variable declaration is really necessary is rather unclear... Kip wrote a module to parse out the HTTP Request object and supply detailed parameters for them (::Request) and I have a module that can take values stored in your BasicSession and supply them to your stylesheet. Yup! Kip, anything about that in your new book? It's in the mail on its way here... :-) Good choice! Its a really great book. I've been an AxKit regular for a while now, and I've learned quite a few things in there. Good! http://nachbaur.com/pgpkey.asc Uhm, you didn't get the new key right, but I'll take that in a private e-mail. :-) Best, Kjetil -- Kjetil Kjernsmo Astrophysicist/IT Consultant/Skeptic/Ski-orienteer/Orienteer/Mountaineer [EMAIL PROTECTED] [EMAIL PROTECTED] [EMAIL PROTECTED] Homepage: http://www.kjetil.kjernsmo.net/OpenPGP KeyID: 6A6A0BBC - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: XSLT-accessed query params and testing existance
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On July 8, 2004 03:53 am, Kjetil Kjernsmo wrote: On onsdag 7. juli 2004, 18:41, Michael A Nachbaur wrote: But then, I need to test whether a parameter exists... In XSP that's straightforward, thanks to the many good taglibs, but I haven't found anything on checking the parameters in XSLT, is it doable? Well, the most common method I know of doing that is: xsl:param name=foo select=''/ Is that line really necessary? Not really. It mainly can be used to supply a default, non-empty, value. So, if you say: xsl:param name=foo select='NULL'/ and then later say xsl:if test=$foo = 'NULL' # No value was supplied /xsl:if that'd do the trick in determining if simply an empty string was supplied. http://nachbaur.com/pgpkey.asc Uhm, you didn't get the new key right, but I'll take that in a private e-mail. :-) Blast it! *sigh* :-) - -- Michael A. Nachbaur [EMAIL PROTECTED] http://nachbaur.com/pgpkey.asc -BEGIN PGP SIGNATURE- Version: GnuPG v1.2.4 (GNU/Linux) iD8DBQFA7WFfQy51zN2518IRAomrAKDtizeBq2YLGJO74e0nEh3zjnFIkgCgi2OU w8ysDYB5j5lILQRlSrNvquE= =dVcR -END PGP SIGNATURE- - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: XSLT-accessed query params and testing existance
On torsdag 8. juli 2004, 16:59, Michael A Nachbaur wrote: Is that line really necessary? Not really. It mainly can be used to supply a default, non-empty, value. So, if you say: xsl:param name=foo select='NULL'/ and then later say xsl:if test=$foo = 'NULL' # No value was supplied /xsl:if that'd do the trick in determining if simply an empty string was supplied. Ah, that's a good idea! But I bumped into something funny, it seems like the line in fact is needed for some applications: My templates now look like this: xsl:param name=title select=''/ xsl:template match=//val:[EMAIL PROTECTED]'title'] xsl:if test=$title = '' xsl:value-of select=//story:story/story:title/ /xsl:if xsl:if test=not($title = '') xsl:value-of select=$title/ /xsl:if /xsl:template xsl:param name=minicontent select=''/ xsl:template match=//val:[EMAIL PROTECTED]'minicontent'] xsl:if test=$minicontent = '' xsl:value-of select=//story:story/story:minicontent/ /xsl:if xsl:if test=not($minicontent = '') xsl:value-of select=$minicontent/ /xsl:if /xsl:template This works as intended. But if I comment out the variable declaration in the xsl:param element, I get an Internal Server Error, and the error message: runtime error: file /news/insert-values-edit.xsl element if unregistered variable title ...but it happens only if title is not supplied at all. Which means, it is more or less needed for robustness. The two above templates aren't a very nice display of Laziness, as you can see... And I need a dozen of those unless I'm able to rewrite it, so that's the other, original question... The variable name is available to the template in //val:[EMAIL PROTECTED], but the problem is making that a variable name... It itches terribly... Cheers, Kjetil -- Kjetil Kjernsmo Astrophysicist/IT Consultant/Skeptic/Ski-orienteer/Orienteer/Mountaineer [EMAIL PROTECTED] [EMAIL PROTECTED] [EMAIL PROTECTED] Homepage: http://www.kjetil.kjernsmo.net/OpenPGP KeyID: 6A6A0BBC - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: XSLT-accessed query params and testing existance
There is of course an entirely different approach which is possible... Have your XSP capture the required input parameters and construct some output XML containing the data you need. Then you have some added flexibility by doing it with perl. I've found that generally thats the better overall technique from a standpoint of general web application structure, since you probably want to validate and scrub those inputs anyway (ie maybe for purposes of avoiding XSS attacks etc. Kjetil Kjernsmo wrote: On torsdag 8. juli 2004, 16:59, Michael A Nachbaur wrote: Is that line really necessary? Not really. It mainly can be used to supply a default, non-empty, value. So, if you say: xsl:param name=foo select='NULL'/ and then later say xsl:if test=$foo = 'NULL' # No value was supplied /xsl:if that'd do the trick in determining if simply an empty string was supplied. Ah, that's a good idea! But I bumped into something funny, it seems like the line in fact is needed for some applications: My templates now look like this: xsl:param name=title select=''/ xsl:template match=//val:[EMAIL PROTECTED]'title'] xsl:if test=$title = '' xsl:value-of select=//story:story/story:title/ /xsl:if xsl:if test=not($title = '') xsl:value-of select=$title/ /xsl:if /xsl:template xsl:param name=minicontent select=''/ xsl:template match=//val:[EMAIL PROTECTED]'minicontent'] xsl:if test=$minicontent = '' xsl:value-of select=//story:story/story:minicontent/ /xsl:if xsl:if test=not($minicontent = '') xsl:value-of select=$minicontent/ /xsl:if /xsl:template This works as intended. But if I comment out the variable declaration in the xsl:param element, I get an Internal Server Error, and the error message: runtime error: file /news/insert-values-edit.xsl element if unregistered variable title ...but it happens only if title is not supplied at all. Which means, it is more or less needed for robustness. The two above templates aren't a very nice display of Laziness, as you can see... And I need a dozen of those unless I'm able to rewrite it, so that's the other, original question... The variable name is available to the template in //val:[EMAIL PROTECTED], but the problem is making that a variable name... It itches terribly... Cheers, Kjetil - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: XSLT-accessed query params and testing existance
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On July 8, 2004 09:01 am, Kjetil Kjernsmo wrote: On torsdag 8. juli 2004, 16:59, Michael A Nachbaur wrote: Is that line really necessary? Not really. It mainly can be used to supply a default, non-empty, value. So, if you say: xsl:param name=foo select='NULL'/ and then later say xsl:if test=$foo = 'NULL' # No value was supplied /xsl:if that'd do the trick in determining if simply an empty string was supplied. Ah, that's a good idea! snip The two above templates aren't a very nice display of Laziness, as you can see... And I need a dozen of those unless I'm able to rewrite it, so that's the other, original question... The variable name is available to the template in //val:[EMAIL PROTECTED], but the problem is making that a variable name... It itches terribly... Well, you can either use the magic of Copy Paste, or you can do some fancy footwork with EXSLT. I don't think CopyPaste needs any explanation. With EXSLT (http://www.exslt.org) you could probably use the eval() function to create an XPath expression and evaluate it, to perform your test. At this point however, I think it might be worth taking a step back and trying to determine what you're getting done, and perhaps refactor what you're doing, instead of trying to force the XSL params functionality into place. Perl-space would be a good spot to look for that. - -- Michael A. Nachbaur [EMAIL PROTECTED] http://nachbaur.com/pgpkey.asc -BEGIN PGP SIGNATURE- Version: GnuPG v1.2.4 (GNU/Linux) iD8DBQFA7YaPvow0fXaFDZQRAtcUAJwO+pAokXjPC6nHg0Q0W+bsYeFoDQCcCKTh KL/gj0LZ0KzRTDRg9hDfCKw= =zfth -END PGP SIGNATURE- - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: XSLT-accessed query params and testing existance
On Jul 8, 2004, at 6:53 AM, Kjetil Kjernsmo wrote: xsl:param name=foo select=''/ Is that line really necessary? Yes, but you can simplify it to xsl:param name=foo/ it will automatically default to '' (empty string) if nothing is passed in. You need it in order to define the param inside the xslt. simon -- http://simonwoodside.com - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: XSLT-accessed query params and testing existance
On torsdag 8. juli 2004, 19:38, Michael A Nachbaur wrote: At this point however, I think it might be worth taking a step back and trying to determine what you're getting done, and perhaps refactor what you're doing, instead of trying to force the XSL params functionality into place. Perl-space would be a good spot to look for that. Hmpf! Yep, I guess so. The reason why I rejected doing it in Perl-space at first was that I couldn't find a way to not load the data twice. Since it is allready available in the document, XSLT seemed ideal to get the data from one place in the document to another... But it seems I should rethink this, indeed. Thanks to all who responded! Kip's book just came in the door! Juhuuu! I'm currently being clued in about the existence of Dahuts! :-) Cheers, Kjetil -- Kjetil Kjernsmo Astrophysicist/IT Consultant/Skeptic/Ski-orienteer/Orienteer/Mountaineer [EMAIL PROTECTED] [EMAIL PROTECTED] [EMAIL PROTECTED] Homepage: http://www.kjetil.kjernsmo.net/OpenPGP KeyID: 6A6A0BBC - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: XSLT-accessed query params and testing existance
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On July 7, 2004 07:56 am, Kjetil Kjernsmo wrote: But this is of little use, because I'd like to have a single template replacing all the possible parameters, so instead of $title, I should use the @name (i.e. the name attribute of the val:insert element), to identify the parameter. That's a pure XSLT/XQuery question I guess, but I might as well ask: Any ideas on how to do that? But then, I need to test whether a parameter exists... In XSP that's straightforward, thanks to the many good taglibs, but I haven't found anything on checking the parameters in XSLT, is it doable? Well, the most common method I know of doing that is: xsl:param name=foo select=''/ xsl:if test=$foo = '' !-- Test to see if no value has been supplied -- /xsl:if xsl:if test=not($foo = '') !-- Test to see if a value has been supplied -- /xsl:if You can probably clean this up a bit by using named templates. xsl:template name=param.foo xsl:choose xsl:when test=$foo = '' xsl:value-of select=$foo/ /xsl:when xsl:otherwise xsl:value-of select=foo/ /xsl:otherwise /xsl:choose /xsl:template Is there more documentation on the parameters AxKit pass to XSLT somewhere now? I remembered an old thread about them and found it in the archives, but that was about all. IIRC, by default it adds the query string parameters supplied to the URL, and any additional parameters added by any AxKit plugins that are supplied. For instance, you can use one of the Apache::AxKit::Plugin::AddXSLParams::* modules to put in additional parameters as needed. Kip wrote a module to parse out the HTTP Request object and supply detailed parameters for them (::Request) and I have a module that can take values stored in your BasicSession and supply them to your stylesheet. Kip, anything about that in your new book? It's in the mail on its way here... :-) Good choice! Its a really great book. I've been an AxKit regular for a while now, and I've learned quite a few things in there. - -- Michael A. Nachbaur [EMAIL PROTECTED] http://nachbaur.com/pgpkey.asc -BEGIN PGP SIGNATURE- Version: GnuPG v1.2.4 (GNU/Linux) iD8DBQFA7Ce5Qy51zN2518IRAuYsAJ0fcK4uz+EXyyNTdFgdVNv+HaGLWACdFmIJ hEVAbuiWrcH45dqYRHa/ng4= =QWDn -END PGP SIGNATURE- - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: XSLT-accessed query params and testing existance
xsl:choose xsl:when test=$url_parameter != '' !-- it was set -- /xsl:when xsl:otherwise !-- it was not set -- /xsl:otherwise /xsl:choose simon On Jul 7, 2004, at 10:56 AM, Kjetil Kjernsmo wrote: But then, I need to test whether a parameter exists... In XSP that's straightforward, thanks to the many good taglibs, but I haven't found anything on checking the parameters in XSLT, is it doable? -- http://simonwoodside.com - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
