All processing within Cocoon is handled within a pipeline. i.e. input, zero or more processing stages, and ultimately some output.
Processing steps are modelled as different types of Components, the simplest pipeline is:
Therefore a pipeline consists of a generator, zero or more transformers and a serializer. A pipeline may also define its own ErrorHandling.
Aggregator allow pipeline to be configured into a hierarchy, producing a compound document.
The map:pipeline element can contain:
- map:match -- Selects pipeline processing depending on Matcher
- map:select, map:when, map:otherwise -- Selector pipeline processing depending on Selector
map:mount -- Mounts a sub Sitemap
map:redirect-to -- Redirects to another pipeline
- map:parameter -- Defines additional parameters for the sitemap components
- map:act -- Peform Action processing
- map:generate -- Defines the Generator step
- map:aggregate, map:part -- Defines an alternate generation step by merging pipelines
- map:transform -- Defines zero or more Transformer steps
- map:serialize -- Defines the final Serializer step
map:handle-errors -- ErrorHandling
Types of Pipeline
- Normal pipelines
Internal pipelines -- can't be accessed externally, can only be addressed from within a sitemap. Specified by internal-only="true" attribute on map:pipeline
Resource pipelines -- basically normal pipelines that act as reusable definitions that can be called by others. See Resources
Error pipelines -- defined within handle-errors section. Fixed error Generator which is provided automatically by Cocoon, subsequent processing under user definition. See ErrorHandling