• You have a development machine with root access
• You have at a minimum, access to the log files on the production machine
• You have some way to stop and start the mod_perl (httpd) process on the production server easily.
• You are doing large scale applications.

Thank you very much for your incisive response! I actually don't have any particular project in mind but wanted to invest my learning wisely. Your response has been very helpful in giving me some criteria to apply to my thinking!
jg
_____________________________________________________
If it gets a little bit out of hand sometimes, don't let it fool you into thinkin' you don't care.TvZ

How common is mod_perl? Common enough for me. ;)

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

Like jeffa, I'm a big fan of HTML::Template. It works well with mod_perl and vanilla CGI, and it's easy to install (and use!). The web designers I work with don't have any problems with it, most importantly dreamweaver seems not to break it.

This node might help you out -- using CGI, DBI and HTML::Template (a mini tutorial with example code)

gav^

To answer your question another way: mod_perl usage statistics were recently discussed on the mod_perl mailing list.

And once you use Template Toolkit for templating, you'll be spoiled for everything else :-)

Chris
M-x auto-bs-mode

It may, perhaps, be rude to answer a question with a question, but I certainly think it in the spirit of the Monastery:

Why would the mod_perl requirement dissuade you from learning HTML::Mason?

I can think of a few possibilities. One, that you feel a bit daunted by the task of learning two new systems whereas HTML::Template does not require that extra bit of work. This is a valid objection, and if you are very eager to get a templating system under your belt, certainly work on HTML::Template first, but put both mod_perl and Mason on your to-do list.

My second thought is that you may not be interested in learning mod_perl because you may not think it applies to what you're doing right now. That may very well be true, but it never hurts to learn something new. You can always find new places to apply knowledge, and acquiring more never hurts.

-Mike-

Actually, my line of thought was basically just my subject line. If mod_perl were significantly uncommon the HTML::Mason becomes less attractive 'cause I couldn't use it on many servers. Thanks for your input. I think I may well follow your advice and do Template first the learn about mod_perl later. I am still a perl newbie, no sense muddling my head with deeper levels just yet.
jg
_____________________________________________________
Never get into a land war in Asia, and never go in against a Sicilian when death is on the line!

It is not true. Mason doesn't actually require mod_perl. It can run as CGI (however it will be very slow). Moreover I've been using it as standalone command line HTML generator.

See HTML::Mason FAQ. Here and here.

--
Ilya Martynov (http://martynov.org/)

Mason doesn't actually require mod_perl. It can run as CGI (however it will be very slow).

Does this mean, mod_perl only provides Mason the persistent CGI process capability? Or, are any other capabilities of mod_perl taken advantage of by Mason?

Put in another way, if the persistence of CGI processes is provided by in a non-mod_perl way (example, FastCGI or SpeedyCGI), does Mason work as effectively as in a mod_perl environment?

Thanks,
/prakash

Does this mean, mod_perl only provides Mason the persistent CGI process capability? Or, are any other capabilities of mod_perl taken advantage of by Mason?

That's right. Mason mostly needs mod_perl for persistence. However there are some sweeties only avialable if you use Mason under mod_perl. Like simple configuration via apache config files and access to Apache API.

Put in another way, if the persistence of CGI processes is provided by in a non-mod_perl way (example, FastCGI or SpeedyCGI)

I heard about people who use Mason this way. You can find some info about it in mason maillist archives.

--
Ilya Martynov (http://martynov.org/)

However, I think HTML::Mason doesn't really require much mod_perl knowledge. It would help you understand what's going on underneath, but you could learn HTML::Mason at a more conceptual level if you wanted. If the main reason you wouldn't learn HTML::Mason is because you're intimidated by mod_perl, I think you can eliminate that reason. The hardest part of HTML::Mason when I first learned it was the initial Apache configuration, but it's well documented and there's a mailing list to read archives or ask questions.

Typically with HTML::Mason, you put HTML at the top of a template page and some Perl at the bottom. The HTML will have special tags in it, similar to JSP or ASP. Then below it, you'll put some Perl code to initialize variables. But I think the powerful thing about HTML::Mason is its "object-orientedness". You can use "autohandlers" to automatically produce parts of the pages, and you can use "methods" that are object-oriented so you can override them and whatnot. I guess in the end it might be just what fits best with your style, so maybe HTML::Template or Template Toolkit makes more sense for you. But knowing mod_perl will still be useful anyway.

I've been using mason for a while now, and I am very happy with it's capabilities. Cool stuff like automatic interception and processing of 404s, argument handling, autohandles, sub-components, inheritable methods keeps me busy trying to figure out how best to utilize it all. The thing that I have found I love most of all, though is the snappy way Mason handles parameters.

A while back, I wanted to learn a templating system. Since I run a little intranet server, and I'm always on the lookout for useful applications I can install and put to use, I looked at what tools were available that I wanted to use, and what they were made with. Tools like Mason-CM, RT, Bricks and Bricolage are all implemented in Mason. We are currently using Mason-CM, customizing RT for use as a workflow tool, and are considering moving some of our documentation to Bricolage. There's some mighty cool stuff out there.

The one thing that mars my love-affair with Mason, is the difficulty I am having finding a cheap host for mason-stuff. To get mason to run in CGI mode, you still need to make changes to the apache config file, which may not be available. Many sites also use mod_perl compiled as a DSO instead of staticly compiled into Apache. There is a bug in mod_perl that Mason treads on hard and often. When used in this configuration Apache tends to seg-fault or die at startup. Not good. Several companies I have contacted were not willing to do a static compile of Apache/mod_perl. It's tempting to use one of them anyway and crash, crash, crash their servers until they repent. But I'm a nice guy.

I have been working with someone on the Mason-Users list to come up with a technique for using mason on a server where you have very minimal access (must install modules into your homedirectory, minimal .htaccess controls, and perl cgi only). I haven't heard from him in a while, so I'm not sure when it will be ready. When it is done, I will post it at masonhq.

TGI says moo