[wp-hackers] Strider Core plugin framework

[Stephen Rider]

Hi all --

This has been in the works for a while, and it's not complete, but  
going by the "release early and release often" philosophy...

I'd like to introduce you to Strider Core.

http://code.google.com/p/strider-core/

Straight from the readme and source:

Strider Core is a framework for use in other plugins.  It is not a  
plugin unto itself.  It includes many points of minor functionality  
and polish, such as Settings page links from the Plugins page, and an  
attribution in the footer of the Settings page.  A significant feature  
is the ability to activate integrated version checking for plugins not  
hosted on WP-Extend.

Strider Core also has an interesting feature in that if multiple  
plugins are built on it, they will all use whichever is the highest  
version present.  Thus, upgrading one plugin can improve all of the  
Strider Core plugins.

NOTE: This framework is still in early development, and thus
	functions may not be entirely stable.  There is no guarantee
	that later pre-1.0 versions will be backward compatible.
	As a public framework, consider it alpha, folks!

How Strider Core versioning works:
  * Every Strider Core plugin loads its own strider_core.php file.
  * The first strider_core.php to be loaded creates the  
load_strider_core()
	function, and sets it to run on the plugins_loaded hook.
  * For each strider_core.php file, the __FILE__ and version (above)
	are loaded into $this_strider_core[], and then passed into
	the $strider_core_info[] array.  $this_strider_core[] is unset.
  * After all plugins are loaded, load_strider_core() runs, in which
	$strider_core_info[] is UNset, and the strider_core.php
	file with the highest version is loaded again
  * This time, the strider_core class is created.  (also,  
$strider_core_info
	is recreated, with data for the current strider_core file only)
  * Finally, the list of Strider Core plugins is looped through
	and each SC plugin "main" file is loaded.  Those files are
	the heart of their respective plugins.

  In the end, you are left with:
	* global $strider_core_info[], which == the $this_strider_core
		array from the top of the active core only
	* global $strider_core_plugins[] -- keys are the plugin
		basename and ['core file'] the "main" file full path for every
		active Strider Core plugin
	* ...and of course, the strider_core class

Known Limitations:
	* "main" plugin file isn't called until plugins_loaded hook.  This is  
soon after normal plugin load, but some things do happen before that.   
Such as...
	* activate and deactivate hooks don't work from the "main" plugin  
files, because those files aren't called until after those hooks are  
fired.

  * Future compatibility note: If an upgrade is ever significantly
	non-backwards compatible, we can simply create load_strider_core_2()
	which will only load legacy SC1 code if needed.  The code that
	hooks plugins_loaded will also un-hook the old load_strider_core()
	as needed.

Known Issues:
	* The Version Check routine is not complete.  Fully WP integrated,
	but lacks the actual code that goes and checks a server for a new
	version.  You can test by upping the version returned by
	filter_set_update_plugins()
	
	* As it is set up currently, the register_version_check_header()
	function is dependent on http://trac.wordpress.org/ticket/8964
	(Though it is not yet used in this beta -- it will be called
	from filter_set_update_plugins() )

	* You can't use activate or deactivate hooks, as neither the
	strider_core_b1 file, nor the "main" plugin file, are called as of
	actual plugin activation/deactivation.

To Do:
	* Fix activate/deactivate hook problem.  Probably can hook a simple
		"container" function from the main plugin file.
		* see core_activate function

Each Admin page should have a second tab for "Strider Core" universal  
settings:
	* Toggle Version Check (default true)
		* Toggle - include compatible non-Strider Core plugins
	* Toggle menu icons

Version Check routine:
	* TEST INPUT of "Version Check URI" w/ wp_kses();
	* fetch latest versions --> TEST INPUT of returned string w wp_kses()
	* after_line_$plugin hook:
		* "skip this version" button ? (use nonces)
		* "Disable updates for this plugin" button ? (use nonces)
	* update_plugin may be written twice per check (in WP) - once for  
update
		time, and once for actual results.  Only run our update routine once!


/* License:
	Strider Core is released under a modified GPL2 license.
	The modification is as follows:
	
	1. If you make _any_ changes to the code, other than for purposes
	of private testing, you are required to change all in-code instances
	of the string "strider_core" -- do a search/replace and replace
	"strider_core" with something unique, e.g. "<yourname>_core".

	2. Do not perform the above replacement using anything containing
	"strider_core".  That is, don't call it "strider_core_2" or
	"my_strider_core" or something.  If you modify it, it isn't
	Strider Core, so really rename it.  (Yes, something very much like this
	has happened in the past.  Somebody branched a program of mine and
	renamed it by adding a "2" to the end. :-\ )

	3. File names and directory names must be similarly altered
	per #2.
	
	4. If you do not do the above (#1, #2, and #3), then Strider Core
	MUST NOT BE MODIFIED IN ANY WAY.
	This is important, because otherwise your modifications could
	adversely affect plugins or software *other than your own!*
	
	--

	If you make modifications and come up with something good,
	please let me know -- I may add it to the original.  :-)


Regards,
Stephen Rider