[opencms-dev] Dynamic Pages (template cache)

[Ivan Biddles]

Thanks, Alex.

Each page has two JSPs associated with it - one for displaying the page,
and the second for routing the incoming requests from that page.

Template
--------

<?xml version="1.0" encoding="utf-8"?>
<PAGE>
    <class>com.opencms.template.CmsXmlTemplate</class>
    <masterTemplate>/system/modules/.../Master</masterTemplate>
    <ELEMENTDEF name="body">
        <CLASS>com.opencms.flex.CmsJspTemplate</CLASS>
        <TEMPLATE>/system/modules/.../Register1Display.jsp</TEMPLATE>
    </ELEMENTDEF>
</PAGE>

Display JSP:
------------

(LinkResolver is just a class with a static method which wraps
LinkSubstitution.getLinkSubstitution, from before the latter became a
static method.)

<%
   CmsObject myCmsObject  = ((CmsFlexRequest) request).getCmsObject ();
   String mySubmitJsp = LinkResolver.resolve (myCmsObject, "/..../
Register1Submitter.jsp ");
%>

<form method="post" name="register" action="<%=mySubmitJsp%>">
etc.

Routing JSP:
-----------

It extracts the request data from the form, makes a back-end validation
call and then either proceeds to the next page or redisplays the
original page with an error message highlighted.

There is no HTML in this JSP at all.

<jsp:useBean       id="testBean" class="TestBean"    scope="session" />
<jsp:setProperty name="testBean" property="*" /> 
<%
   String  myLinkPage = "";
   boolean myIsValid  = testBean.validate ();

   if (myIsValid) {
      myLinkPage = LinkResolver.resolve (request,
"/..../register2.html");
   }
   else {
      myLinkPage = LinkResolver.resolve (request,
"/..../register1.html");
   }
   response.sendRedirect (myLinkPage);
%>

Java Classes
------------

I use the normal CmsXmlTemplate class. My back-end classes are called by
the routing JSP, so they are not really relevant.

That is just about it. I have the control page for "register1.html" set
to "export=dynamic". (I need it to be "export=https", but that's another
issue I'm tracking down.)

Thanks for your help.

Best wishes,   Ivan


-----Original Message-----
From: owner-opencms-dev at www.opencms.org
[mailto:owner-opencms-dev at www.opencms.org] On Behalf Of Alexander
Kandzior
Sent: Monday, January 20, 2003 09:53
To: opencms-dev at www.opencms.org
Subject: RE: [opencms-dev] Dynamic Pages (template cache)

Ivan,

I can assure you integrating dynamic parts from JSP in a template is no
general problem. Maybe it's in your way of using the JSP integration. If
you post the significant parts from your template, JSP and your java
classes here I will take a look. 

Best Regards,
Alex.

Alexander Kandzior
Alkacon Software - The OpenCms Experts
http://www.alkacon.com

> -----Original Message-----
> From: owner-opencms-dev at www.opencms.org 
> [mailto:owner-opencms-dev at www.opencms.org] On Behalf Of Ivan Biddles
> Sent: Monday, January 20, 2003 6:23 PM
> To: opencms-dev at www.opencms.org
> Subject: RE: [opencms-dev] Dynamic Pages (template cache)
> 
> 
> Hi Christian,
> 
> Thanks, but I already do that. It is not the element cache 
> that is causing the problem - it is this "template cache".
> 
> I created my own subclass of CmsXmlTemplate just for the 
> purpose of trying to solve this problem. All it has is an 
> override of the getCacheDirectives method in which I return 
> "new CachDirectives(false)", as it says to do in the manual. 
> But the manual also says that it is for the "element cache".
> 
> I have disabled the element cache, and added a logging line 
> to CmsObject that proves that the element cache reference 
> returned from the "init" method is always null.
> 
> However nothing seems to turn off the "template cache", which 
> is hard-coded to create a cache of 1000 entries.
> 
> I have an ugly temporary workaround in that I have changed 
> the CmsTemplateCache "put" method to not store template 
> content in the template cache if the supplied key matches one 
> of my dynamic pages. This is the only thing I have found that 
> stops the behaviour, but this cannot be the solution.
> 
> Can someone tell me how to turn this thing off selectively 
> and by configuration, or at least without having to change 
> the OpenCms code?
> 
> Thanks,
>          Ivan
> 
> -----Original Message-----
> From: owner-opencms-dev at www.opencms.org 
> [mailto:owner-opencms-dev at www.opencms.org] On Behalf Of 
> Hoffmann, Christian
> Sent: Monday, January 20, 2003 00:39
> To: 'opencms-dev at www.opencms.org'
> Subject: AW: [opencms-dev] Dynamic Pages (template cache)
> 
> Hi Ivan,
> 
> maybe you should use getCacheDirectives()? It is described in 
> Section 2.3.9 (pages 63-69) in the Manual.
> 
> Christian
> 
> > -----Ursprüngliche Nachricht-----
> > Von: Ivan Biddles [mailto:ivanb at scientology.net]
> > Gesendet: Montag, 20. Januar 2003 09:17
> > An: opencms-dev at www.opencms.org
> > Betreff: [opencms-dev] Dynamic Pages (template cache)
> > 
> > 
> > Hi,
> > 
> > I have been struggling with an issue that my dynamic pages
> > are generated once, when online, but then the JSPs are never 
> > run again and the same version is always displayed.
> > 
> > I have specified these pages as "export=dynamic", and
> > everything works perfectly in the off-line project.
> > 
> > I tracked it down to the "template cache". I had already
> > tried disabling both the element and flex caches without success.
> > 
> > (The template cache is only mentioned twice in the Manual,
> > both times in the Javadoc section - pages 200 and 215.)
> > 
> > What I found was that my JSP would run once and then its
> > _output_ would be stored in the template cache. From then on 
> > OpenCms simply serves up the page as it was originally created.
> > 
> > This means that Person A logs in and goes to some page and
> > gets a display of some personal information, let's say. Then 
> > Person B does the same thing but he sees Person A's 
> > information, because OpenCms is only se5rving up one version 
> > of this page.
> > 
> > In CmsTemplate Cache, I found the following code:
> > 
> >       // TODO: get the cache-size from properties
> >       private CmsCache templateCache = new CmsCache(1000);
> > 
> > So there is no way to turn off this cache from the property file.
> > 
> > There must be some way of controlling this behaviour.
> > 
> > I'm sure others must tried to create dynamic pages, so it
> > must be some setting that I have got wrong somewhere, but I 
> > haven't been able to find what it is.
> > 
> > So any help is urgently needed and would be greatly appreciated.
> > 
> > Thanks,
> >            Ivan
> > 
>