Chapter 16. Extending Smarty With Plugins
Version 2.0 introduced the plugin architecture that is used
for almost all the customizable functionality of Smarty. This includes:
- functions
- modifiers
- block functions
- compiler functions
- prefilters
- postfilters
- outputfilters
- resources
- inserts
With the exception of resources, backwards compatibility with the old
way of registering handler functions via register_* API is preserved. If
you did not use the API but instead modified the class variables
$custom_funcs,
$custom_mods, and
other ones directly, then you will need to adjust your scripts to either
use the API or convert your custom functionality into plugins.
How Plugins Work
Plugins are always loaded on demand. Only the specific modifiers,
functions, resources, etc invoked in the templates scripts will be
loaded. Moreover, each plugin is loaded only once, even if you have
several different instances of Smarty running within the same request.
Pre/postfilters and output filters are a bit of a special case. Since
they are not mentioned in the templates, they must be registered or
loaded explicitly via API functions before the template is processed.
The order in which multiple filters of the same type are executed
depends on the order in which they are registered or loaded.
The plugins directory
can be a string containing a path or an array containing multiple
paths. To install a plugin, simply place it in one of the
directories and Smarty will use it automatically.
