Related ORM Nested Set Extension

Nested Sets for the Related ORM.

• Inserts, updates, deletes nested set nodes
• Support for multiple root nodes and multiple trees per table
• Works on any property names
• Prevents nodes with child nodes from being deleted

API

Importing and loading

Import

var   ORM 		= require('related')
	, NestedSet = require('related-nested-set');

Load the ORM

var orm = new ORM(dbConfig);

Load the extension using the default settings, the columns have the name left and right. The table contains one tree only.

orm.use(new NestedSet());

Load using custom column names

orm.use(new NestedSet({
	  left: 'lft'
	, right: 'rgt'
}));

Load for a table containing multiple tree grouped by a column

// myDB is the name of the db containing nested set table
// myTable is the table containing the nested set
orm.use(new NestedSet({
	myDB: {
		myTable: 'groupingColumn'
	}
}));

You may also set the grouping key afterwards

var nestedSet = new NestedSet();

// add to orm
orm.use(nestedSet);

// when the orm is loaded everything should be ready
orm.load(function(err) {

	// add grouping
	nestedSet.setGroupKey(databaseName, modelName, keyName);
});

loadTree method

Load a tree from a table which has only one tree stored in it

orm.myDB.myTable().loadTree(function(err, tree){});

Load a tree with the id 234 from a table which has multiple trees stored in it

orm.myDB.myTable().loadTree(234, function(err, tree){});

querybuilder.loadTree(callback);

setParent method

model.setParent([primary key value | model instance | query builder], [as last child]);

This method can be called on any model instance of a nested set. It sets a new parentnode for the current node.

// load a node from the table
orm.tree({id:4}).findOne(function(err, node){

	// set as a new root node
	node.setParent();


	// set as child of another parent, using its the parent nodes id as reference
	node.setParent(45);


	// set as child of another model instance
	node.setParent(modelInstance);


	// set as last child of a node found using a query, set as last child
	node.setParent(orm.db.tree({name: 'charlie'}), true);


	// save changes
	node.save(function(err) {

	});
});

after method

model.after(primary key value | model instance | query builder);

Positions this model after another model on the same level

// load a node from the table
orm.tree({id:4}).findOne(function(err, node){

	// store after the node with the id 45
	node.after(45);


	// store after the modelInstance
	node.after(modelInstance);


	// store after the node with the name «charlie»
	node.after(orm.db.tree({name: 'charlie'}), true);


	// save changes
	node.save(function(err) {

	});
});

before method

model.before(primary key value | model instance | query builder);

Positions this model before another model on the same level

// load a node from the table
orm.tree({id:4}).findOne(function(err, node){

	// store before the node with the id 45
	node.before(45);


	// store before the modelInstanc

e node.before(modelInstance);

	// store before the node with the name «charlie»
	node.before(orm.db.tree({name: 'charlie'}), true);


	// save changes
	node.save(function(err) {

	});
});