Hierarchical Data plugin for Bookshelf.js (WIP)

- http://mikehillyer.com/articles/managing-hierarchical-data-in-mysql/
- https://github.com/cakephp/cakephp/blob/master/src/ORM/Behavior/TreeBehavior.php
- https://github.com/PhilWaldmann/openrecord/blob/master/lib/stores/sql/plugins/nested_set.js

Example

Example data from test-data.sql:

``
mysql> source show-tree.sql;
+----+------------------------+
| id | name |
+----+------------------------+
| 1 | ELECTRONICS |
| 2 | TELEVISIONS |
| 3 | TUBE |
| 4 | LCD |
| 5 | PLASMA |
| 6 | PORTABLE ELECTRONICS |
| 7 | MP3 PLAYERS |
| 8 | FLASH |
| 9 | CD PLAYERS |
| 10 | 2 WAY RADIOS |
+----+------------------------+
`

$3

`js
var Category = ORM.Model.extend({
tableName: 'nested_category',
nestedSet: true,
});
`

You can configure the default configuration in the nestedSet key:

`js
{
fields: {
left: 'lft',
right: 'rgt',
parentId: 'parent_id',
}
}
`

$3

`js
// load the plugin
ORM.plugin(require('bookshelf-hierarchy').NestedSetModel);

// wrap in transaction
ORM.transaction(t => {

// save a new child node under TELEVISIONS
new Category().save({name: '3D TV', parent_id: 2}, {transacting: t})
.then(category => {

// removes FLASH from under MP3 PLAYERS
new Category().removeFromTree({id: 8}, {transacting: t}).then(res => {
t.commit();
});

});
})
`

$3

`js
// get children of PORTABLE ELECTRONICS
Category.forge().fetchAll({
findChildren: {
for: 6,
direct: false, // set true to retrieve direct nodes
}
})
`

$3

`js
// get nodes leading to 3D TV (id 11)
Category.forge().fetchAll({
findPath: {
for: 11
},
transacting: t,
})
`

$3

`js
// move TELEVISIONS (2) under PORTABLE ELECTRONICS (6)
new Category().setParent(2, 6, {transacting: t}).then(() => {
console.log('node moved')
});
`

$3

`js
// Configuring scope for a model instance with section_id = 2:
new Category({}, {scope: {section_id: 2}}).fetchAll({
})
`

Running tests

`mysql < test-data.sql ; npm test`

Todo

- [x] transaction support
- [x] findPath
- [x] findChildren
- [ ] findTreeList
- [ ] formatTreeList
- [x] removeFromTree
- [x] setParent
- [ ] moveUp
- [ ] moveDown
- [ ] recover