These extensions process content, i.e. they either convert data from one format to another or make other changes to the data. Content processors are used, for example, in the transformation pipeline of page and template paths.

It is not specified how content processors have to process the content, they are free to do anything, even binary transformations (e.g. creating a thumbnail from a picture). Each content processor is identified by one or more short names (used, for example, in the pipeline option of a block in a path in Webgen Page Format) which are listed on the documentation page of a content processor.

Information about how to create a content processor is found in the Webgen::ContentProcessor API documentation.

Content processors can be divided into several groups which are shown below.

Special purpose processors

These processors perform very useful tasks which are nearly always used in the transformation pipeline of page/template paths.

Replaces a special xml tag with the rendered block of a node in Webgen Page Format
Provides a very easy way for adding dynamic content
Generates fragment nodes from all HTML headers which have an id attribute set
Inserts various HTML tags like links to CSS/Javascript files into the HTML head tag

Markup Processors

These processors convert markup text that is easy to read and write to a more structured format like HTML. This allows you to write an HTML page without knowing HTML.

Fast superset-of-Markdown to HTML converter
Converts content written in a superset of Markdown to HTML
Converts content written in Markdown to HTML
Converts content written in RDoc markup to HTML
Converts content written in Textile markup to HTML

Template Engines

These processors are used to add dynamic parts to the processed content.

Allows one to programatically create valid XHTML/XML documents
Allows one to use ERB (embedded Ruby) in the content
Allows one to use ERB (embedded Ruby) in the content (faster than the erb processor)
Allows one to write HTML with the Haml markup language
Generate arbitrary output using plain Ruby

CSS Preprocessors

These processors allow you to write CSS files in an easier way, for example, they allow the usage of variables to avoid spreading the same data over the whole file.

Converts content written in the Sass meta language to valid CSS
Converts content written in the Sassy CSS language to valid CSS

Post Processors

These processors are used to post-process HTML files.

Compresses CSS files
Uses the tidy program to convert the content into valid (X)HTML
Uses the xmllint program to check the content for well-formedness and/or validness

Other Processors

These processors don’t fit into any of the above categories.

Converts the content (LaTeX TikZ picture commands) into an image