 |
- |
+ |
+ |
The content repository accomodates these situations in the +
The content repository accommodates these situations in the following ways:
-
-
- An API procedure, content_type.register_child_type, may be +
- An API procedure, content_type.register_child_type, may be used to specify the minimum and maximum number of children of a particular content type that an item may have. You may optionally specify a "tag" for identifying child items of the same type. For example, you may want to allow only 1 image with the "featured" tag, and up to 8 other images without this. -
- A Boolean API function, content_item.is_valid_child, +
- A Boolean API function, content_item.is_valid_child, which checks all registered child constraints on the content type of an item and returns true if it is currently possible to add an child of a particular type to tan item. Note that this function does not protect against concurrent transactions; it is only foolproof if you -lock the cr_child_rels table beforehand. +lock the cr_child_rels table beforehand. -
- A mapping table, cr_child_rels, which contains two -attributes, order_n and relation_tag, that may be +
- A mapping table, cr_child_rels, which contains two
+attributes, order_n and relation_tag, that may be
used to characterize the parent-child relationship. Parent-child
relationships are themselves treated as ACS Objects, so this table may
be extended with additional attributes as required by the
@@ -82,7 +82,7 @@
Note that there is no currently no explicit API to "add a child." You specify the parent of an item upon creating it. You can use the -API procedure content_item.move to change the parent of an +API procedure content_item.move to change the parent of an item.
Item-Object Relationships
@@ -99,24 +99,24 @@ is provided for parent-child relationships:-
-
- An API procedure, content_type.register_relation_type, +
- An API procedure, content_type.register_relation_type, may be used to specify the minimum and maximum number of relations with a particular object type that an item may have. There is no limitation on the type of objects that may be related to content items. If you wish to relate content items to other content items, however, the object type should specify a content type (a subtype of -content_revision) rather than simply content_item. +content_revision) rather than simply content_item. As for parent-child relationship constraints, ou may optionally specify a "tag" for identifying related objects of the same type. -
- A Boolean API function, content_item.is_valid_relation, +
- A Boolean API function, content_item.is_valid_relation, which checks all registered constraints on the content type of an item and returns true if it is currently possible to relate an object of a particular type to an item. -
- A mapping table, cr_item_rels, which contains two -attributes, order_n and relation_tag, that may be +
- A mapping table, cr_item_rels, which contains two
+attributes, order_n and relation_tag, that may be
used to characterize the item-object relationship. Item-object
relationships are themselves treated as ACS Objects, so this table may
be extended with additional attributes as required by the
@@ -133,7 +133,7 @@
karlg@arsdigita.com
-Last modified: $Id$ +Last modified: $Id$