2.2. Attributes / Fields / Indexing

Archetypes are using schemas (also called schemata) with fields to define the form-fields on your content. The schema and its fields of your content types is generated from the attributes of your classes in your model and their tagged values. Each field has a type and a widget.

The Archetypes documentation and the quick reference at the end of this document describes which fields are available and what parameters they take as configuration.

Usage of tagged values

If you set a tagged value on an attribute of your class, in general that tagged value will be passed through as a parameter to the generated Archetypes field. Hence, if you set a tagged value enforceVocabulary to the value 1 on an attribute, you will get enforceVocabulary=1 for that field in the generated schema. Similarly, you can set a field's widget properties by prefixing the tagged value with widget:. widget:label sets the label of a widget, for instance.

Non-string tagged values

As before, when reading tagged values, ArchGenXML will generally treat them as strings, with a few exceptions where only non-string values are permitted, such as the required tagged value. If you do not wish your value to be quoted as a string, prefix it with python:. For example, if you set the tagged value default to python:["high", "low"] on a lines attribute, you will get default=["high", "low"] in a LinesField in your schema.

field recycling - copy from parents schema or another source schema and modify

This feature alows you to copy a field from another source schema and rename the field.

Rather than subclass an entire class then delete unwanted fields, you can explicitly copy just the fields you need. You can keep the copied field "as-is" or modify it by overriding properties with tag values as needed.

For example you may need a Description field that is usually defined in your parent classes (BaseContent, BaseFolder) Schema. You would create a new attribute in your class named description with a type of copy. If you want it to appear in your base_edit form rather then the default of properties/metadata page you just need to change one property of the field by adding the tag schemata = "default".

You may also copy from any other schema or from within the same schema. You need to specify the source schema using the tag copy_from and if you need to rename the field use the source_name tag to indicate the source field Id, otherwise the Id of the field in you schema is used.

Index and metadata in catalogs and Collection

ArchgenXML can create configuration files to create an index and/or metadata entries in the catalog such as portal_catalog.

Available are the following tagged values:

catalog:index

add the field to the index. Boolean, 1 or 0. Default is 0. If set, you may need to provide index:* tagged values too.

catalog:metadata

add the field to the metadata record on the query result? Boolean, 1 or 0. If you do not provide index:attributes, the name of the accessor of the field is the default. If catalog:metadata_accessor is given it will be used instead.

catalog:metadata_accessor

the accessor used for the metadata (string).

catalog:name

sometimes you need to add an index to a other catalog than portal_catalog and its XML-File catalog.xml. Provide a tuple of comma separated strings, id of the catalog and the filename of its configuration file. default is "portal_catalog, Plone Catalog Tool'.

index:type

the type of index used as (string), for example FieldIndex, KeywordIndex, DateIndex or any available index in your portal. For known types a default is guessed, such as FieldIndex for StringFields or DateIndex for DateFields. If no guess is possible, we assume a FieldIndex.

index:attributes

the attributes to use for index (string or comma separated list of strings). This are the methods called at indexing time. Normally it is enough to provide one index method, but for some specific use cases you might need to provide alternatives. If you do not provide this tagged value, the name of the accessor of the field is the default.

index:name

the name of the index used (string). Use this name in your queries. If you do not provide a name, the name of the accessor of the field is the default.

index:extras

some indexes are using so called extras on installation as configuration. If the index need extras you'll need to declare them here. provide a comma separated list.

index:properties

some indexes are using properties on installation as configuration. If the index need properties you'll need to declare them here. Provide a comma separated list.

collection:criteria

add the index to the Collection (aka Smart Folder) Indexes available for defining Criteria. Provide a comma seprated list of criteria that will be available by default. Available criterias are: ATBooleanCriterion, ATDateCriteria, ATDateRangeCriterion, ATListCriterion, ATPortalTypeCriterion, ATReferenceCriterion, ATSelectionCriterion, ATSimpleIntCriterion, ATSimpleStringCriterion, ATSortCriterion, ATCurrentAuthorCriterion, ATPathCriterion, ATRelativePathCriterion. You must provide an index:type as well.

collection:criteria_label

the display name of the collection:criteria, called friendly name (string). Its added to the generated.pot as a literal. If not given the widget:label is taken if provided.

collection:criteria_description

a help text (string), used for collection:criteria. Its added to the generated.pot as a literal. if not provided the widget:description is used.

collection:metadata

register the catalog:metadata as an available column in a Collection. Can be used as an alternative for catalog:metadata. catalog:metadata_accessor is used if given.

collection:metadata_label

the display name of the collection:metadata, called friendly name (string), used for index:criteria. Its added to the generated.pot as a literal. If not given the widget:label is taken if provided.

collection:metadata_description

a help text (string), used for collection:criteria. Its added to the generated.pot as a literal. If not provided the collection:criteria_help or - if not provided - widget:description is used.

DEPRECATED For backward compatibility reasons we support a sub part of the old style in ArchGenxML Version 1.6 and earlier using the tagged value index. This is deprecated and will be removed in one of the next version of ArchGenXML. A tagged value index with value like index:type above creates an index with the accessor. To include the index in catalog metadata (and have the attribute ready to use in the brain objects), append :brains (same as older :schema), (e.g. FieldIndex:brains). ArchGenXML does longer provides the ability to define multiple indexes using the old declaration style.

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