1. Best Practices for Elgg Plugin
Developers
Cash Costello
ElggCamp San Francisco

2. Best Practices for Elgg Plugin
Developers
Cash Costello
ElggCamp San Francisco

3. About Me
Elgg core developer
Author of Elgg Social Networking 1.8
Employed by Johns Hopkins University Applied
Physics Laboratory (JHU/APL)
R&D in machine learning
Driving force behind JHU/APL's collaborative
platform built on Elgg

4. 1. Namespace your functions, classes, actions,
views, CSS, JavaScript

5. 2. Make dependencies between plugins explicit
Plugin manifest, function_exists(), elgg_is_active_plugin()

6. 3. Create a site customization plugin as a catch all
for small modifications
Maintain a readme with list of customizations!

7. 4. Keep your plugin's start.php trim
elgg_register_library(), elgg_load_library(), class with static
methods

8. 5. Use inheritance with Elgg's data model
Remember to unregister your class when your plugin is disabled
using the deactivate.php script with update_subtype()

9. 6. Document what metadata is used with your
entities
@property in documentation of class or use getter/setter methods

10. 7. Avoid using many metadata key-value pairs
with elgg_get_entities*()

11. 8. Use Elgg's functions and classes when
interacting with the data model

12. 9. Be aware that setting metadata on an entity
clears Elgg's database cache

13. 10. Use relationships to connect entities
Not metadata!

14. 11. Do not create large views

15. 12. Create views that correspond to visual
elements
Also look for common elements that can be reused

16. 13. Use the core views and CSS classes
whenever possible

17. 14. Learn the principles behind Elgg's new HTML/
CSS
Example: CSS selectors should not cross element boundaries

18. 15. Test with non-admin user and while logged
out