The EPrints 3 workflow configuration files are stored in the repository's workflows directory, within folders identifying the Data Objects to which they apply (e.g. eprint or user). Multiple workflows may be defined in each folder, although typically only the default.xml file will be necessary.
At the centre of a workflow is a 'flow' description. This denotes the path through the workflow process from stage to stage. This may contain EPrints Control tags, allowing for the flow to vary depending on parameters of the data object (or other objects). For example, the flow may be different for users with certain roles. The flow is structured like so:
<flow> <stage ref="type"/> <stage ref="files"/> <stage ref="core"/> <stage ref="subjects"/> </flow>
The 'ref' attribute of the stage element refers to the individual stages. The stage elements describe the components within each screen of the process and, like flow, may contain EPrints Control tags. The 'name' attribute of the stage element is identical to that of the stage element in the 'flow' section.
<stage name="core"> <component><field ref="title" required="yes" /></component> <component><field ref="abstract"/></component> </stage>
An EPrints component is responsible for the rendering of a graphical element in a workflow. This may be a text-box for title entry, a collection of fields in an appropriate grouping, or just a piece of XHTML. Six components are provided by default and, as they are plugins, it is straightforward to drop in new components when necessary. The type attribute of the component element corresponds to the plugin to be used.
The majority of field-related components in EPrints 3 make use of the field element in their configuration. This provides a reference to a metafield and any attributes which may be relevant to rendering or operation. Several attributes are available to the element:
|ref||A string||(required) Refers to the name of the metafield this field represents|
|required||yes/no||(optional) Whether a value is required in this field before the workflow may complete|
|help||An XHTML block||(optional) A block of XHTML to be rendered as help for the field|
|input_lookup_url||A URL||(optional) The location of an auto-lookup URL for the field|
|input_lookup_params||A string||(optional) An &-separated list of parameters (e.g. sort=descending&number=3|
The default component, this renders the field title, an input box suitable for the field, a star if the field is required, and any help information. A single field element is required:
<component><field ref="title" required="yes" /></component>
Multiple Field Component
The multiple field component is able to render several fields in a group, such as all fields related to a publication or an event. A title element and a help element may be provided that describe the group itself. One or many field elements are also required.
<component type="Field::Multi"> <title>Event Details</title> <help>Enter information about your event here.</help> <field ref="event_title"/> <field ref="event_type" required="yes" /> <field ref="event_location"/> <field ref="event_dates"/> </component>
The subject component allows for the selection of one or more subjects from a subject tree. In this instance, the field element specifies the subject metafield.
<component type="Field::Subject"> <field ref="subjects" required="yes" /> </component>