by Chadwick Wood
December 17th, 2008
Because of some recent need I had to do some search engine optimization (SEO) and spam blocking, I've come across some really great Drupal modules that I wanted to mention. A lot of you out there who build Drupal sites may already know about them, but here goes...
Mollom is a spam-blocking module for all of your content on a Drupal site, including your comment forms, contact forms, sign-up form, etc. You can set it up to only protect the forms you want, too.
If any of you use Akismet for blocking spam in WordPress, Mollom works the same way: when new content is submitted, the content gets sent to the Mollom servers and checked against their database of known spam, and returns a result to your site, indicating whether or not the content is spam. It goes a little further than Akismet, though (as far as I can tell): if it's not "sure" about whether the content is spam, it displays a CAPTCHA to the user that can be filled out to indicate that the content is legit.
Thanks to Justin Ziccardi for informing me on this one!
XML Sitemap automatically builds a sitemap for you, and optionally submits the sitemap to a number of search engines. Sitemaps are used by Google and other search engines to more efficiently crawl your content and display search results. From my reading, there is debate over how important sitemaps are at the moment, but this module makes it easy to generate them, so why not?
If you're using Drupal 6, be aware that this module is still in development and doesn't yet have a stable release. However, I'm using the development version of it and it seems to be working fine so far. The version of this module for Drupal 5 is stable.
Global Redirect essentially makes sure that each page on your site has one and only one URL that points to it. For instance, by default Drupal will accept a URL with our without a trailing slash; both URLs will go to the same page. This is potentially bad for SEO as search engines might penalize your site for having "duplicate content" (the same content at more than one address). Global Redirect will strip those trailing slashes, as well as perform a handful of other operations with the same goal. You can read the specifics of it on the module page (linked to above).
Page Title gives you better control over what goes in the