mongoose-tree

Implements the materialized path strategy for storing a hierarchy of documents with mongoose

Warning: the original code is from Brian Kirchoff, but it seem's that he no longer take care of mongoo-tree.
https://github.com/briankircho/mongoose-tree

Usage

Install via NPM

$ npm install mongoose-tree2

Then you can use the plugin on your schemas

``javascript
var tree = require('mongoose-tree2');

var UserSchema = new Schema({
name : String
});
UserSchema.plugin(tree);
var User = mongoose.model('User', UserSchema);

var adam = new User({ name : 'Adam' });
var bob = new User({ name : 'Bob' });
var carol = new User({ name : 'Carol' });

// Set the parent relationships
bob.parent = adam;
carol.parent = bob;

adam.save(function() {
bob.save(function() {
carol.save();
});
});
`

At this point in mongoDB you will have documents similar to

{
"_id" : ObjectId("50136e40c78c4b9403000001"),
"name" : "Adam",
"path" : "50136e40c78c4b9403000001"
}
{
"_id" : ObjectId("50136e40c78c4b9403000002"),
"name" : "Bob",
"parent" : ObjectId("50136e40c78c4b9403000001"),
"path" : "50136e40c78c4b9403000001#50136e40c78c4b9403000002"
}
{
"_id" : ObjectId("50136e40c78c4b9403000003"),
"name" : "Carol",
"parent" : ObjectId("50136e40c78c4b9403000002"),
"path" : "50136e40c78c4b9403000001#50136e40c78c4b9403000002#50136e40c78c4b9403000003"
}

The path is used for recursive methods and is kept up to date by the plugin if the parent is changed

API

$3

Signature:

getChildren([recursive], cb);

if recursive is supplied and true, subchildren are returned

Based on the above hierarchy:

`javascript
adam.getChildren(function(err, users) {
// users is an array of with the bob document
});

adam.getChildren(true, function(err, users) {
// users is an array with both bob and carol documents
});
`

$3

Signature:

getChildrenTree([args], cb);

return a recursive tree of subchildren.

args is an object you can defined with theses properties :

filters: mongoose query filter, optional, default null
example: filters: {owner:myId}

columns: mongoose columns, optional, default null (all columns)
example: columns: {"_id name owner"}

options: mongoose query option, optional, default null
example: options:{{sort:'-name'}}

minLevel: level at which will start the search, default 1
example: minLevel:2

recursive: boolean, default true
make the search recursive or only fetch childs for the specified level
example: recursive:false

emptyChilds: boolean, default true
if true, every childs not having subchilds will have childs attribute (empty array)
if false, every childs not having subchilds will not have childs attribute

Example :

`javascript
var args = {
filters: {owner:myId},
columns: {"_id name owner"},
minLevel:2,
recursive:true,
emptyChilds:false
}

getChildren(args,myCallback);
`

Based on the above hierarchy:

`javascript
adam.getChildren(function {

/* if you dump users, you will have something like this :
{
"_id" : ObjectId("50136e40c78c4b9403000001"),
"name" : "Adam",
"path" : "50136e40c78c4b9403000001"
"childs" : [{
"_id" : ObjectId("50136e40c78c4b9403000002"),
"name" : "Bob",
"parent" : ObjectId("50136e40c78c4b9403000001"),
"path" : "50136e40c78c4b9403000001.50136e40c78c4b9403000002"
"childs" : [{
"_id" : ObjectId("50136e40c78c4b9403000003"),
"name" : "Carol",
"parent" : ObjectId("50136e40c78c4b9403000002"),
"path" : "50136e40c78c4b9403000001.50136e40c78c4b9403000002.50136e40c78c4b9403000003"
}]
}]
}
*/

});

`

$3

Signature:

getAncestors(cb);

Based on the above hierarchy:

`javascript
carol.getAncestors(function(err, users) {
// users is an array of adam and bob
})
`

$3

Equal to the level of the hierarchy

`javascript
carol.level; // equals 3
``

Tests

To run the tests install mocha

npm install mocha -g

and then run

mocha