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Create object hierarchies based on json schema


Creates model/collection hierarchies based on JSON schema.

Based on JSON-Schema specification, but it's slightly modified regards handling relations etc.

var addressSchema = exports.addressSchema = {
  id: '/schemas/address',
  title: 'Address',
  type: 'object',
  properties: {
    street: { type: 'string' },
    city: {type: 'string'},
    country: {type: 'string'}
var Address = Model.extend({
  type: 'address',
  schema: addressSchema
var address = new Address({
  street: '221B Baker Street ',
  city: 'London',
  country: 'England'


Relations are defined as

type: 'relation'
collection/model: ModelName

Thus relations can be either Models or Collections.

var Addresses = exports.Addresses = Collection.extend({
  model: Address
var personSchema = exports.personSchema = {
  id: '/schemas/person',
  type: 'object',
  properties: {
   addresses : {
      type: 'relation',
      collection: Addresses
var person = new Person({
  addresses: [{street: 'Baker Street', city: 'London', country: 'GB'}]

Initing a relation might need information from the main model. This is done by passing a references - options to the property. E.g.

  properties: {
    owner: {
      type: 'relation',
      model: Person,
      references: {id: 'owner_id'}

will read the value of owner_id property from the main model, and init relation automatically with it. So e.g. if a Model has {owner_id: 2}, owner relation will be inited with:

person = new Person({id: 2})

Validation is done by jsonschema module. Validating Models can be created by extending from ValidatingModel.

var schema = {
  id: '/schemas/foo',
  type: 'object',
  properties: {
    data: {
      type: 'string'
var Foo = ValidatingModel.extend({
  type: 'foo',
  schema: schema
var f = new Foo({data: 'a'});
var errors = f.validate();

Will give an error, since 'data' had incorrect type.

If you want to make more complex validations, that jsonschema does not support, you can extend the customValidation method, see tests for more info.

Passing option {recursive: true} to toJSON, will also include relation in the JSON output. Sometimes it's useful to control which attributes are included in the JSON. This can be done with projection settings. E.g.

var projection = {
  owner: ['id', 'title'],
  removeFields: ['addresses']
var json = person.toJSON({recursive: true, projection: projection});

will include only 'id' & 'title' fields from the owner relation and will remove the 'addresses' relation completely from the output.

onlyFields option will whitelist the given properties, thus includes only the specified properties in the JSON output.

removeFields option will blacklist the given properties, thus removes the specified properties in the JSON output.

You can define a projection preset in the schema, e.g.

properties: {
projection: {
  mini: {
    onlyFields: ['city']

Then you can give projection options as

person.toJSON({recursive: true, projection: 'mini'})

A property can define convert function which is called when attribute is set. E.g.:

    properties: {
      id: {
        type: 'integer',
        convert: function(attribute) {
          return Number(attribute);
      }, ...

This project is based on

The MIT License