Defining Tasks
All tasks to be used in a publication must be declared in the file [publication-directory]/content/tasks.xconf. A typical task configuration file looks like follows:
<?xml version="1.0"?>
<tasks>
<!-- publish page -->
<task id="publish">
<label>Publish</label>
<task id="publish" class="org.lenya.cms.publishing.DefaultFilePublisher">
<parameter name="live-path" value="content/live"/>
<parameter name="tree-live-path" value="content/live/tree.xml"/>
</task>
<task id="export" class="org.lenya.cms.publishing.StaticHTMLExporter">
<parameter name="export-path" value="resources/export/pending"/>
<parameter name="substitute-regexp" value="s/\/lenya\/your-publication//g"/>
</task>
</task>
</tasks>
Every task must have a unique id attribute. This identifier is used to address the task from the sitemap. Every top-level task must have a child element <label>. The content of this element is used, e. g., by the scheduler to let the user choose a task from a list. The actual implementation of a task is identified using the class attribute.
Parameters
Usually, a task needs some parameters to be executed properly. There are two possibilities to pass parameters to a task:
- You can define all parameters or a subset of them in the tasks.xconf file.
- The remainig parameters can be handled to the TaskAction or the TaskJob that executes the task. Request parameters always have a higher priority than parameters from the tasks.xconf file.
To simplifiy the passing of parameters to tasks, the TaskAction and TaskJob objects create some default parameters based on the request and session objects:
-
Task.PARAMETER_SERVLET_CONTEXT - the path of the servlet context
/home/user_id/build/jakarta-tomcat/webapps/lenya -
Task.PARAMETER_SERVER_URI - the server URI
http://www.yourhost.com:8080/lenya/publication/index.html -
Task.PARAMETER_SERVER_PORT - the server port
http://www.yourhost.com:8080/lenya/publication/index.html -
Task.PARAMETER_CONTEXT_PREFIX - the part of the URI that precedes the publication ID
http://www.yourhost.com:8080/lenya/publication/index.html -
Task.PARAMETER_PUBLICATION_ID - the publication ID
http://www.yourhost.com:8080/lenya/publication/index.html
Task Sequences
Tasks can be nested using so-called task sequences. Sub-tasks of other tasks don't need to have <label> elements because they can't be addressed independently. Whenever a task sequence is executed, all sub-tasks are executed in the same order as they are declared.
When you group tasks, the enclosing <task> element does not need a <class> attribute. If you omit it, the TaskSequence class is used as default. If you want to implement your own task grouping mechanism using a subclass of TaskSequence, you can append a class attribute.
All parameters that are passed to a TaskSequence are forwarded to all tasks in the sequence. By creating a subclass of TaskSequence you could implement a parameter selection mechanism, e. g. using namespace prefixes.
Assigning Tasks to Document Types
Every document type can support a set of tasks. The labels of these tasks are displayed on the scheduler screen of a document of this type. To assign a task to a document type, you have to edit the file [publication-directory]/config/doctypes/doctypes.xconf:
<doctypes>
<doc type="Simple-Document">
<tasks>
<task id="publish"/>
<task id="backup"/>
...
</tasks>
</doc>
...
</doctypes>
You can associate every task with an arbitrary number of document types.