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This model can retrieve information about the resource category hierarchy in different ways.<\/p>\n

Categories are the principal categorization (typing) system of resources. Every page is assigned to exactly one\ncategory. Categories themselves are organized in a tree-like hierarchy.<\/p>\n

A category is a resource with a special category<\/code> record attached to it to store metadata related to the category\nhierarchy. The m_category<\/code> model provides accessors to this category tree and individual category information.<\/p>\n

An example of a category tree, as returned by {% print m.category.tree %}<\/code>:<\/p>\n

[[{id,101},\n  {parent_id,undefined},\n  {level,1},\n  {children,[]},\n  {path,"e"},\n  {left,1000000},\n  {right,1000000}],\n [{id,104},\n  {parent_id,undefined},\n  {level,1},\n  {children,[[{id,106},\n              {parent_id,104},\n              {level,2},\n              {children,[[{id,109},\n                          {parent_id,106},\n                          {level,3},\n                          {children,[]},\n                          {path,"hjm"},\n                          {left,4000000},\n                          {right,4000000}]]},\n              {path,"hj"},\n              {left,3000000},\n              {right,4000000}]]},\n  {path,"h"},\n  {left,2000000},\n  {right,4000000}],\n  ...]\n<\/code><\/pre>\n
About the complete category tree<\/h2>\n
The following m_category model properties are available in templates:<\/p>\n
Property<\/th>Description<\/th>Example value<\/th><\/tr><\/thead>
tree<\/td>Return the complete forest of category trees as nested property lists.<\/td>See above.<\/code><\/td><\/tr>
tree2<\/td>Return the forest of category trees as nested property lists. Up to the children of the children.<\/td>See above.<\/code><\/td><\/tr>
tree_flat<\/td>Return a list of tuples for the category tree. This list is intended for select lists. There is a special field for the indentation. The returned list consists of proplists. The list does not contain the "meta" category, which contains the categories "predicate", "category" etc.<\/td>See above entries.<\/code><\/td><\/tr>
tree_flat_meta<\/td>Same as tree_flat but with the categories in the meta category.<\/td>See above entries.<\/code><\/td><\/tr><\/tbody><\/table>\n
About a single category<\/h2>\n
The m_category has some special properties defined when fetching a category, they are accessed by id or category name.\nFor example:<\/p>\n
{{ m.category[104].tree }}\n{{ m.category.text.tree }}\n<\/code><\/pre>\n
Property<\/th>Description<\/th>Example value<\/th><\/tr><\/thead>
tree<\/td>The category tree below and including the indexing category.<\/td>See above.<\/code><\/td><\/tr>
tree1<\/td>The list of direct children below the indexing category.<\/td>See above.<\/code><\/td><\/tr>
tree2<\/td>The category tree below and including the indexing category, up to the children of the children.<\/td>See above.<\/code><\/td><\/tr>
tree_flat<\/td>The category tree below and including the indexing category, up to the children of the children. As a flattened list.<\/td>See above.<\/code><\/td><\/tr>
path<\/td>List of parent category ids from the root till the category, excluding the indexing category.<\/td>[ 104, 106 ]<\/code><\/td><\/tr>
is_a<\/td>List of the parent category names form the root till the category, including the current category.<\/td>[ text, article, news ]<\/code><\/td><\/tr>
image<\/td>A random depiction for this category. The returned image filename comes from one of the pages within this category.<\/td><<"2009\/10\/20\/flat-world-proof.jpg">><\/code><\/td><\/tr>
parent_id<\/td>The page id of the parent category. Returns an integer or, for a root category, undefined.<\/td>104<\/code><\/td><\/tr>
nr<\/td>The category nr. Used for building the tree, will change when categories are added or removed. An integer.<\/td>2<\/code><\/td><\/tr>
level<\/td>The depth of the category. Level 1 is the root, 2 and more are below the root.<\/td>1<\/code><\/td><\/tr>
left<\/td>The lowest value of the nr range of this category, including its sub categories.<\/td>2<\/code><\/td><\/tr>
right<\/td>The highest value of the nr range of this category, including its sub categories.<\/td>8<\/code><\/td><\/tr>
name<\/td>The unique page name of this category. A binary.<\/td><<"text">><\/code><\/td><\/tr>
path<\/td>The path through the hierarchy of categories to this category.<\/td>[104, 106]<\/code><\/td><\/tr><\/tbody><\/table>\n
Available Model API Paths<\/h2>\n
Method<\/th>Path pattern<\/th>Description<\/th><\/tr><\/thead>
get<\/code><\/td>\/tree\/...<\/code><\/td>Return full category forest as nested hierarchy records (all non-meta roots and descendants).<\/td><\/tr>
get<\/code><\/td>\/tree2\/...<\/code><\/td>Return category forest in the limited tree2<\/code> representation (up to grandchildren level).<\/td><\/tr>
get<\/code><\/td>\/menu\/...<\/code><\/td>Return category forest formatted for menu rendering (hierarchy plus display metadata).<\/td><\/tr>
get<\/code><\/td>\/tree_flat\/...<\/code><\/td>Return flattened category list for selection UIs, excluding the meta<\/code> branch.<\/td><\/tr>
get<\/code><\/td>\/tree_flat_meta\/...<\/code><\/td>Return flattened category list including the meta<\/code> branch categories.<\/td><\/tr>
get<\/code><\/td>\/is_used\/+cat\/...<\/code><\/td>Return whether any resource is assigned to +cat<\/code> or one of its descendant categories.<\/td><\/tr>
get<\/code><\/td>\/+cat\/path\/...<\/code><\/td>Return ancestor category id path for +cat<\/code>; returns undefined<\/code> when category is unknown.<\/td><\/tr>
get<\/code><\/td>\/+cat\/is_a\/...<\/code><\/td>Return is_a<\/code> ancestry (category names) for +cat<\/code>; returns undefined<\/code> when category is unknown.<\/td><\/tr>
get<\/code><\/td>\/+cat\/tree\/...<\/code><\/td>Return nested subtree rooted at +cat<\/code>; returns undefined<\/code> when category is unknown.<\/td><\/tr>
get<\/code><\/td>\/+cat\/tree_flat\/...<\/code><\/td>Return flattened subtree list rooted at +cat<\/code>; returns undefined<\/code> when category is unknown.<\/td><\/tr>
get<\/code><\/td>\/+cat\/tree1\/...<\/code><\/td>Return direct-child tree level for +cat<\/code>; returns undefined<\/code> when category is unknown.<\/td><\/tr>
get<\/code><\/td>\/+cat\/tree2\/...<\/code><\/td>Return subtree of +cat<\/code> in tree2<\/code> format (up to grandchildren); returns undefined<\/code> when unknown.<\/td><\/tr>
get<\/code><\/td>\/+cat\/image\/...<\/code><\/td>Return a random depiction filename from resources in category +cat<\/code>; returns undefined<\/code> when category is unknown.<\/td><\/tr>
get<\/code><\/td>\/+cat\/...<\/code><\/td>Return category record for +cat<\/code> (id\/name\/nr\/level\/left\/right\/parent metadata); returns undefined<\/code> when unknown.<\/td><\/tr><\/tbody><\/table>\n
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