Joe’s hacky approach to getting arbitrary behavior out of Drupal
Wherein I disqualify myself for work as a “drupal developer”
Self indulgent history part
Way back in 1999 when I started out writing web apps, Embperl seemed like the logical tool to use — so I’m used to having direct access to every step in the request-to-response process. In years since, I’ve progressed through a bunch of different tools and approaches, which have included writing a few rudimentary content management systems and using a bunch of prexisting ones.
Over the last few years I’ve become a big fan of ruby on rails, so if a site does much of anything (simple, recent example: The Food Project’s online summer program application), that’d be my starting point.
so, why use Drupal?
Even so, when a site is basically about some content that’s written and edited on an ongoing basis by other folks, Drupal starts looking like a reasonable tool. It’s pretty easy to get it to generate semantic output with reasonable URLs, and the editor-facing UI does a fair job of offerring a large degree of control and customizability without being overwhelmingly complex.
Despite having done some custom work on a few live Drupal sites, I still get confused about the best way to do some of the arbitrary web interaction tasks that were so straightforward back in the Embperl days. There are a billion modules in the Drupal ecosystem, but I often find that it takes more time to figure out if there is an appropriate one for my task & if it works with the current version of Drupal than it would to code up a solution on my own. Also, while I’ve made several attempts to solve programming tasks in what I understand to be the Drupal way, wrapping my head around all the relevant APIs (which can totally change every 6-12 months, with each Drupal release) similarly tends to take more time than bypassing Drupal’s functionality & handling things in Plain Old PHP.
Here’s a common approach I’ll take, then. I have no interest in extensive coding through a web browser (i.e. putting a bunch of PHP in a node or block), so I’ll set up a Drupal module to hold my application’s arbitrary php functions. Then I’ll create a page at the desired URL and enter a line of PHP to route the GET and/or POST to my code, as appropriate.
Example
I’m working on an email list signup that needs to communicate with a FileMaker database. An HTML form POSTs to http://thefoodproject.org/mailing_list_signup, which is just a Drupal page using the PHP input filter (which you now need to turn on via admin settings) containing <?php tfp_process_list_signup($_POST); The code for that function lives in sites/all/modules/tfp/tfp.module, and does the normal PHP things to pull information out of the POST & hand that info off to the FileMaker database. Here’s a bit of it:
function tfp_process_list_signup($_POST) {
$reply = '';
$sent_plausible_address = FALSE;
if ($_POST['email']) {
$supplied_email = $_POST['email'];
if (preg_match(PLAUSIBLE_EMAIL, $supplied_email)) {
$sent_plausible_address = TRUE;
$reply = "Thanks! We'll add your to our mailing list.";
} else {
$reply = "'$supplied_email' doesn't look like an email address to me. ";
}
//. . .
}
return $reply;
}
On the upside, this is quick & easy. The downside with this approach vs. writing a module the Drupal way is that I’m losing out on Drupal’s form API and its associated validation, antispoofing, etc. services. On the upside, last time I checked the linked documentation for the form API, it said
Warning - this page has only been partially updated for the Drupal 6.x API
Until it has been fully updated, reference this page as well: Drupal 5.x to 6.x FormAPI changes
so I’m quite happy to not have to wade through all of that!