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<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>That’s a pretty broad question, but three basic ideas come
to mind. First start by factoring as much common code as possible out
into separate classes. If they are asking for major differences in their
custom versions, using a version control system and branching for their changes
might be a good idea, but it brings with it the overhead of maintaining
branches and backporting fixes as needed. If the customizations are not
so vast, you can use a Strategy pattern to codify the customizable behaviors
into interchangeable classes and then either create an Admin page or a config
file where they can select the ones they want.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>But I think the solution you choose will depend on the sort of
customization you’re facing. In general I think the design practise
of creating well-defined interfaces for the various components of your app
makes it easy to create interchangeable components and behaviors. Whether
you are picking the components at runtime with some configuration options or at
compile time by actually selecting a subset of files to deploy (via makefiles
or version control) is not as important in my mind.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>I’m sure there are many other possible solutions as
well. If you could provide some more info about the sorts of
customizations I think you’ll probably get some interesting answers.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Byron</span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
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<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Michael Reddick
[mailto:michael.reddick@gmail.com] <br>
<b>Sent:</b> Thursday, April 02, 2009 1:32 PM<br>
<b>To:</b> catalyst@lists.scsys.co.uk<br>
<b>Subject:</b> [Catalyst] Custom changes to different instances of the same
app<o:p></o:p></span></p>
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<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>If you have a Catalyst app installed at several different customers,
and they all want their own customizations, whether it be to the interface or
the business logic, what are some different strategies for doing that using
good coding standards?<br>
<br>
Thanks,<br>
Michael<o:p></o:p></p>
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