Module Development

Attachments and Caching with the Render API for Drupal 7

Check your version

This tutorial covers a topic in Drupal 7 which may or may not be the version you're using. We're keeping this tutorial online as a courtesy to users of Drupal 7, but we consider it archived.

Alternate resources

Sprout Video

This chapter walks through how you can conditionally add either JavaScript or CSS to a content element as well as how to cache the content with Drupal's caching system. Additional notes: The cache will clear the first time cron.php is run AFTER whatever time you've specified as the cache expiration date in your code. Which you could easily calculate to be 30 seconds in the future and then store that timestamp in the database. However, you would also need to make sure that cron was running frequently enough to clear the cache every 30 seconds.

Render Arrays overview (