[geeklog-devel] Plugin Version Control and Dependencies (feature request #0001154)

[Rouslan Placella]

I'd like to implement the dependency checks for geeklog plugins (bug
#0001154).
So below I wrote down some things that I think I'll have to do for this.
Feedback? Suggestions? Opinions? Tips?

Thanks,
Rouslan.

THINGS TO DO (or to keep in mind):
* Create two database tables: 
	Store each plugin's dependencies in one table
	and each plugin's log from the latest install attempt in the other
table

	TABLE plugin_dependencies
	  pi_name      varchar(30) // Name of the plugin to which an entry
belongs
	  type         varchar(20) // 'geeklog', 'plugin', etc...
      require      varchar(30) // name of the required plugin (leave
empty if $type is 'geeklog')
	  version      varchar(20) // version of the required plugin
	  operator     varchar(10) // type of comparison, e.g: ">=" or ">"

	TABLE plugin_install_log   // here we save custom messages that are
generated when a plugin's install function is called 
	  pi_name      varchar(30)
	  type         varchar(20) // 'notice', 'info', 'warning', 'error',
etc...
	  title        TEXT        // a title
	  msg          TEXT        // a message


* Create a new plugin API call: plugin_dependencies_pluginname()
    The plugin can return a two-dimentional array containing its
dependency information and it's install log.
	Sample usage in the plugin would be:
		<?php
		// plugins/foo/autoinstall.php:
		...
		function plugin_dependencies_foo()
		{
			...
			return array(
				// This array says that the plugin 'foo' requires Geeklog version
greater than or equal to 1.8.0
				array( 'geeklog' => 'core', '1.8.0' => '>=' ),

				// This array says that the plugin 'foo' requires the calendar
plugin with version greater than 1.0.0
				array( 'plugin' => 'calendar', '1.0.0' => '>' ),

				// There can be multiple dependencies
				array( 'plugin' => 'socnet', '1.0.0' => '>=' ),

				// A message from the plugin regarding custom dependency checks
				// $type can be 'notice', 'info', 'warning', 'error', etc...
				array( 'message' => 'error', 'a title' => 'a message' ),

				// There can be multiple messages
				array( 'message' => 'info', 'another title' => 'another message' )
  
				/*  The settings will be saved to 'plugins_dependencies' table and
                    the messages to 'plugins_install_log'  */
			);
		}
		...
		?>

* Introduce a function to update and resolve dependencies, as well as
ensuring that the plugins are loaded in the correct order.
    Call this function:
		* when enabling/disabling a plugin
		* when installing/uninstalling a plugin
		* when changing plugin load order
		* when loading plugins?

* Add the "plugin editor" to uninstalled plugins.
	* If there was an install attempt and it failed, show the entries from
the "plugin_install_log" table there.
	* When warning about unresolved dependencies. Offer the options to:
"try to resolve", "proceed anyway" and "cancel operation".
	* Add a clear_install_log($plugin) function and use it before each
install so that there is only one log entry per plugin.
	* In the plugin admin, make it obvious when there is a message that was
saved during the install and it can be viewed.

* Show dependency information in the plugin editor for enabled plugins

* Show the install log in the plugin editor for enabled plugins
    It'll probably say: "Installation was successful." only, most the
time, but it could be useful to add custom information messages.

* Keep backwards compatibility with all older plugins

* Should be easy to extend to dependencies for databases (maybe even
themes and blocks, too?).

* Add a plugin_dependencies_* functions to the bundled plugins

* Document everything better than this
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://pairlist8.pair.net/pipermail/geeklog-devel/attachments/20110121/7358aa18/attachment.html>