Developer documentation

Note: New developer documentation pages should be added to the Development namespace by typing Development: before the new page name i.e. [[New page name]].

If you are a developer, you probably want to change your preferences to include the Development namespace in searches.

Guidelines

The following guidelines are crucial reading for anyone wanting to contribute to the Moodle code base:

• Coding guidelines have to be followed by all Moodle developers
• Moodle design goals spells out the basic design goals behind Moodle
• Interface guidelines aim to provide a common feel to the Moodle user interface
• Moodle CVS for developers explains how to work with the Moodle code in CVS
• Unit tests explains how to run the unit tests, and how to write new test cases.
• Tracker explains the Moodle Tracker for keeping track of bugs, issues, feature requests etc
• Working with the Community explains how to engage with the dev community and discuss changes

Resources and tools

• Developer FAQ - frequently asked questions, especially useful for newcomers to Moodle
• Moodle tracker - bug reports, feature requests and other tracked issues
• General developer forum
• CVS code - browse the Moodle code via the web
• Cross reference - phpxref output for browsing Moodle source code
• Moodle PHP doc reference - automatically generated documentation
• Database Schema - for recent releases
• Development news and discussion section of Using Moodle course
• YUI documentation - YUI is the official AJAX library in moodle.
• Setting up Eclipse for Moodle development - Eclipse is a great editor to use for php development, if you can work out how to set it up.
• Unmerged files - changes on the stable branch in CVS that have not been merged to HEAD
• Firefox tracker search - How to setup a firefox quicksearch to easily navigate to moodle bugs
• Ctags - Using a tags file to navigate code

How you can contribute

The M in Moodle stands for 'Modular'. There are many different types of components that you can contribute that can be plugged into Moodle to provide additional functionality. When you have developed a new component please publish it in the database of Moodle modules and plugins. The following types of plugins currently exist (in alphabetical order):

• Activity modules
• Admin reports
• Assignment types
• Authentication methods
• Blocks
• Course formats
• Database fields
• Database presets
• Enrolment plugins
• Filters
• Question engine
• Question import/export formats
• Quiz reports
• Resource types
• SSO plugins

There are also ways you can contribute that don't involve PHP programming:

• Themes
• Translation
• Database schemas

You can also help a lot by

• Testing
• Participating in the bug tracker

Plans for the future

Ideas for and details of planned future features of Moodle are initially discussed on the forums in the Using Moodle course at moodle.org. That developer discussions are intermixed with user discussions in the same forums may seem strange at first but is one of the reasons for the success of Moodle. It is important that both end-users and developers discuss the future features together.

Once ideas begin to crystalize on the forums they can be summarized in this wiki, either as part of the Roadmap or in the form of Developer notes. These pages then form the basis for further discussion in the forums.

• Roadmap
• Developer notes
• Student projects
• Developer conferences

Documentation for core components

This section is for documentation of specific components of the existing core Moodle code. Discussion of components that are under discussion or in development can be found in the Developer notes or on the Roadmap.

Core components that affect everything

• lib/moodlelib.php
• lib/weblib.php for outputting stuff.
• Database abstraction layer @ v1.7
• Roles and Capabilities system @ v1.7 for controlling who can do what.
• Forms library @ v1.8 for creating accessible and secure HTML forms that let users edit things.

Core libraries with a more specific uses

• Authentication API
• Cookieless Sessions
• Moodle Network
• Email processing
• Environment checking before install, check the user's server to ensure Moodle will work there.
• Question engine
• Stats package
• Migration to UTF-8 @ v1.6

Modules included in the standard distribution

• Quiz module
• SCORM module 1.5 schema

Documentation for contributed code

Many Moodle users contribute code for the benefit of other Moodle users. This can take the form of new activity modules, blocks, themes, resource plug-ins, assignment plug-ins, question type plug-ins, question import/export formats, quiz report plug-ins, course formats, ... This code is initially posted on the forums in the Using Moodle course and then often goes into the contrib area of the Moodle CVS repository. When you have developed a new component please publish it in the database of Moodle modules and plugins. Developer documentation for these components should be listed here.

See also

• Moodle Security Centre
• Moodle Partners - providers of custom Moodle development services