The following is the standard for plugin structure in Elgg as of Elgg 2.0.
The following is an example of a plugin with standard structure. For further explanation of this structure, see the details in the following sections. Your plugin may not need all the files listed
The following files for plugin example
would go in /mod/example/
actions/ example/ action.php other_action.php classes/ VendorNamespace/ ExampleClass.php languages/ en.php vendors/ example_3rd_party_lib/ views/ default/ example/ component.css component.js component.png forms/ example/ action.php other_action.php object/ example.php example/ context1.php context2.php plugins/ example/ settings.php usersettings.php resources/ example/ all.css all.js all.php owner.css owner.js owner.php widgets/ example_widget/ content.php edit.php activate.php deactivate.php CHANGES.txt COPYRIGHT.txt INSTALL.txt LICENSE.txt manifest.xml README.txt start.php
Plugins must provide a start.php
and manifest.xml
file in the plugin root in order to be recognized by Elgg.
Therefore the following is the minimally compliant structure:
mod/example/ start.php manifest.xml
Plugins should place scripts for actions an actions/
directory, and furthermore should use the name of the action to determine the location within that directory.
For example, the action my/example/action
would go in my_plugin/actions/my/example/action.php
. This makes it very obvious which script is associated with which action.
Similarly, the body of the form that submits to this action should be located in forms/my/example/action.php
. Not only does this make the connection b/w action handler, form code, and action name obvious, but it allows you to use the new (as of Elgg 1.8) elgg_view_form()
function easily.
Plugins may provide various *.txt as additional documentation for the plugin. These files must be in Markdown syntax and will generate links on the plugin management sections.
- README.txt
- should provide additional information about the plugin of an unspecified nature
- COPYRIGHT.txt
- If included, must provide an explanation of the plugin's copyright, besides what is included in
manifest.xml
- LICENSE.txt
- If included, must provide the text of the license that the plugin is released under.
- INSTALL.txt
- If included, must provide additional instructions for installing the plugin if the process is sufficiently complicated (e.g. if it requires installing third party libraries on the host machine, or requires acquiring an API key from a third party).
- CHANGES.txt
- If included, must provide a list of changes for their plugin, grouped by version number, with the most recent version at the top.
Plugins may include additional *.txt files besides these, but no interface is given for reading them.
To render full pages, plugins should use resource views (which have names beginning with resources/
). This allows other plugins
to easily replace functionality via the view system.
Note
The reason we encourage this structure is
- To form a logical relationship between urls and scripts, so that people examining the code can have an idea of what it does just by examining the structure.
- To clean up the root plugin directory, which historically has quickly gotten cluttered with the page handling scripts.
Elgg provides PSR-0 autoloading out of every active plugin's classes/
directory.
You're encouraged to follow the PHP-FIG standards when writing your classes.
Note
Files with a ".class.php" extension will not be recognized by Elgg.
Included third-party libraries of any kind should be included in the vendors/
folder in the plugin root. Though this folder has no special significance to the Elgg engine, this has historically been the location where Elgg core stores its third-party libraries, so we encourage the same format for the sake of consistency and familiarity.
In order to override core views, a plugin's views must be placed in a views/
. This directory has special meaning to Elgg as views defined here automatically override Elgg core's version of those views. For more info, see :doc:`/guides/views`.
Javascript and CSS will live in the views system. See :doc:`/guides/javascript`.
The activate.php
and deactivate.php
files contain procedural code that will run respectively upon plugin activation or deactivation. Use these files to perform one-time events such as registering a persistent admin notice, registering subtypes, or performing garbage collection when deactivated.