Scripting

Scripting

XWiki integrates both Velocity and Groovy scripting. Together, these two mechanisms allow you to create basic to complex web applications at the XWiki page (or view) layer without the need for compiling code or deploying software components. In other words, you can use Velocity and Groovy script syntax in addition to wiki and HTML syntax as the contents of an XWiki page.

XWiki's Velocity API

The concept of the 'context' is central to Velocity. The context is a 'carrier' of data between the Java layer of the XWiki engine and the template or page layer. The programmers of the XWiki core have gathered objects of various types and placed them in the Velocity context. These objects, and their methods and properties, are accessable via template elements called references and effectively form an API for XWiki.

The API is documented in Javadoc format and can be accessed here: XWiki API Javadoc. If you are not familiar with Java or object oriented programming, you will probably be confused by the API documentation. It is not within the scope of our documentation to teach you all the details about Velocity, Java, or object oriented programming. You can find all of that information already online. Instead, we provide only a high-level overview in Basic Velocity Scripting Tutorial; it will give you a good sense for how Velocity scripting works in XWiki. You should then refer to the Velocity User Guide as an ongoing reference. Finally, you can explore the page code found throughout the Code Zone area to see how others have figured out how to achieve a variety of results.

You can access in your velocity script to :

• The current document: $doc
• The Context of the request: $context
• the request object: $request
• the XWiki Object: $xwiki

To include Velocity scripts in other Velocity scripts, see How to include a velocity page into another page.

XWiki's Groovy API

Currently Groovy is only allowed for admins of a wiki (or users having the 'programming' right).

• See Groovy examples in the Code Zone, more specifically in the Code Snippets area
• Feeling Groovy
• MVC programming with Groovy templates
• Guillaume Laforge on Groovy, XWiki etc.