Sequelize Nested Set

Library to store and manage nested set trees using Sequelize. It supports multi-root trees.

Feel free to create an issue or PR if you have a bug or idea.

Installation

Warning! This library is on beta testing! Be careful with using it.

npm i sequelize-nested-set

Getting started

This library works as a wrapper for sequelize.define, it has the same params: model name, attributes (aka table fields), options, but the first 2 params are sequelize connection and DataTypes object.

const ns = require('sequelize-nested-set');

module.exports = (sequelize, DataTypes) => {
    const Tag = ns(sequelize, DataTypes, 'Tag', {
        label: DataTypes.STRING,
    }, {
        tableName: 'tag',
        timestamps: false,
        hasManyRoots: true,
    });
    
    // add additional methods, associations to the model
    
    return Tag;
};

Table structure

Yes, it requires a basic structure of table where you want to keep your tree.

Here are the required fields:

• lft - int, not null. You can use another column name using lftColumnName option.
• rgt - int, not null. Use rgtColumnName option for custom column name.
• level - int, not null. For its name you can also use levelColumnName option.

If you want to store a multi-root tree (several trees in other words), you need to set hasManyRoots option to true and have one more column:

• rootId - int, not null. Default field name is root_id, but you can also use your own with rootColumnName option.

Nested Set Options

There are several options to customize your nested set:

• hasManyRoots (boolean, default: false) - for cases when you want to store several trees in one table.
• lftColumnName (string, default: lft) - a column name for lft.
• rgtColumnName (string, default: rgt) - a column name for rgt.
• levelColumnName (string, default: level) - a column name for level.
• rootColumnName (string, default: root_id) - a column name for rootId. Value of this option makes sense only if hasManyRoots is true.