I tend to do a lot of roster pages on Drupal + CiviCRM sites (Drupal Views, exposing CiviCRM contact record fields). One of the search filters I'd like to try would be to allow visitors to enter a postal/zip code and then have results from contacts that are located in a radius to the postal code. I know CiviCRM has some ability to geocode contact addresses. Is there any way we can harness the goecoding into a postal/zip filter for this type of search?
I have recently updated the module to allow a map and use your location. More info can be found here - https://civicrm.org/blog/anil/drupal-views-civicrm-contact-distance-search-with-a-map
You would need to do some custom work to get this exposed to a public page I suspect, but CiviCRM already provides radius search, based on Zip Code.
First you need to turn on geocoding which will go get the latitude/longitudes for all the contacts you have (based on their zip code). Go here to set up: civicrm/admin/setting/mapping (note you have to allow civi the time to fully geocode your contacts as well.)
Then in Advanced Search, you can search a zip code, and say you would like to search a specific radius around that zip. (Note if geocoding is not turned on, the option to specify a radius is not displayed.)
Using Drupal Views, assuming you are geocoding,you may be able to create a view based on a radius using that stored lat/long (though that may be prohibitive CPU wise). Depends on how many contacts you need to filter. (Probably need to use a PHP filter in the view to calc the distance on each contact to determine inclusion.)
(Google for the algorithm to calc distances on lat/long)
As luck would have it, I was over at the Drupal project review queue and found exactly what I was looking for. It's currently on its path to being approved (hopefully soon) and currently it only supports UK postal codes but this is what I expect will be the answer (it's a sandbox project at this time):
CiviCRM contact distance search https://www.drupal.org/sandbox/vakeesan26/2498395