Sequelize Transforms

Sequelize plugin to add configurable attribute transforms. It allows you to define transform functions (aka filters) to run on attribute values when an instance is updated (through assignment, set, build, create etc.). The transform functions can be enabled and configured on attribute level.

Installation

npm install sequelize-transforms

Activation

Globally

To activate the plugin for all your models, call the plugin on your sequelize instance:

var sequelizeTransforms = require('sequelize-transforms');

sequelizeTransforms(sequelize);

Per Model

To activate the plugin on specific models, call the plugin on the models:

var sequelizeTransforms = require('sequelize-transforms');

var Model = sequelize.define('Model', { /* model definition */ });
sequelizeTransforms(Model);

Usage

To use transforms for an attribute, just add them to its definition:

var Model = sequelize.define('Model', {
  email: {
    type: Sequelize.STRING,
    lowercase: true,
    trim: true
  }
});

With this configuration, the email attribute will always be trimmed and transformed to lower case.

Predefined Transforms

The plugin comes with the following predefined transforms:

• trim: trim value
• lowercase: transform value to all lower case
• uppercase: transform value to all upper case

Custom Transforms

It is possible to override predefined transforms or add your own by passing an object as the second argument:

sequelizeTransforms(sequelize, {
  trim: function(val, defintion) {
    return val.toString().replace(/ /g, '*');
  },
  append: function(val, definition) {
    return val.toString() + definition['append'];
  }
});

This would override the trim transform and add a new one called append. Every transform function is called with two parameters: the value to transform and the definition of the attribute being transformed.

Notes

• If more than one transform is defined on an attribute, then the order in which they are executed is unpredictable. This is generally not an issue as you should not use mutually exclusive transforms together, e.g. lowercase and uppercase.
• If an attribute is updated with the raw option set to true, then the transforms will not be run.