Drupal 7’s Fields API – Initial Perspective

Drupal 7’s Fields API – Initial Perspective

Posted on: Thursday, December 8th 2011 by Richard Mo

I’m sure that there's a lot of blogs, tutorials, and presentations out in the public already, which educate us about the Fields API. I’m not going to write “another blog post” about that. Instead, I'm going to share my initial impression as well as what I’ve discovered helpful to people who are new to the API.

Fields creation for content-types behaves exactly the same as CCK module of Drupal 6: selection of fields that can be attached, widget types that can be used with a field, and configuration of fields. The UI, in particular, looks almost identical to CCK module. So, a lot of the basic field types from the CCK module are part of core Drupal 7, however, like I said, it’s only the basic, if I want to have a more complex setup, I must default to something more appropriate…

From experience, CCK API is not easy to work with. If you want to create a set of textfield and textarea, group them as a whole, and allows for multiple sets. CCK can give you a headache. I’m actually quite impressed of how Fields API greatly simplifies the creation process. Although the learning curve is quite steep, yet once you learned where things are its quite easy. (As a side note, the API documentation on Drupal.org is not beginner-friendly.) So to help out our fellow Drupal 7 developers, there are five things you must implement in order for a field to work:

1. hook_field_info()
2. hook_field_is_empty()
3. hook_field_widget_info()
4. hook_field_widget_form()
5. hook_field_schema()

The hook_field_validate(), hook_field_formatter_info(), and hook_field_formatter_view() is not required for the field to work.