[development] DEP - cascading variable system

[Adrian Rossouw]

On 30 Nov 2005, at 2:00 AM, Zack Rosen wrote:

> This is a very cool idea Adrian.  I have a few questions...
>
> * Other than the theme_get_variable function is there other code  
> this helps you abstract?
> * Do you got good ideas of use cases where different users want  
> different settings variables?  I definitely see the coolness of  
> letting people have different configs for their blog / organic  
> groups, but not quite getting the advantage of letting users  
> configure the site to their own preference.
We already do this for all user specific settings (like whether or  
not tinymce is enabled.)

> * What in the heck is the user interface going to look like for  
> managing different sets of settings?

(i'll add this to the bottom)

User interface doesn't change, only the flexibility of where saved  
settings take effect is added.
So instead of saving settings to the data column in the user table,  
or stuffing all of the theme specific settings
in a single variable, we store them in a nice normalised table.

You would set variables using
function variable_set($variable, $value, $domain = null, $id = null) {

and you would get variable using
function variable_set($variable, $default, $domain = null, $id = null) {

The code specified default would go to the bottom of the queue, followed
by the defaults the install profile specified (install profiles need  
this. otherwise
any default setting change involves changing code wherever it happens)
followed by the system wide settings, followed by the layout/section/ 
theme specific
settings (this is the next DEP I want to write) and then at the very  
top of the stacks,
the system overrides (like when a hosting provider doesn't want  
people to touch
the files dir)

[5] $GLOBALS['override']
[4] user settings. system table, user domain, userid key.
[3] theme settings. system table, theme domain, theme name key.
[2] system settings. system table, system domain.
[1] $GLOBALS['defaults']
[0] $default



--
Adrian Rossouw
Drupal developer and Bryght Guy
http://drupal.org | http://bryght.com