Embedding a Subset of One Archetype's Properties in another Archetype

archetype-20171020-pick.js

const Archetype = require('archetype');

// Simplified customer type for the sake of example. This customer
// type has 2 top-level properties: a string `email` and an object
// `name` that has nested string properties `first` and `last`.
const CustomerType = new Archetype({
  name: {
    first: { $type: 'string' },
    last: { $type: 'string' }
  },
  email: {
    $type: 'string'
  }
}).compile('CustomerType');

// The `.pick()` function takes an array of property names. Once you
// compile the new archetype below, you'll get a type with only one
// property, `name`.
const RequestCustomerType = CustomerType.pick(['name']).compile('RequestCustomerType');

// `RequestCustomerType` is an archetype, which means you can use it
// as a property value. Remember that composability is a core design
// goal of Archetype: you can re-use all or part of an archetype in
// another archetype.
const RequestType = new Archetype({
  customer: { $type: RequestCustomerType },
  createdAt: { $type: Date }
}).compile('RequestType');

const customer = new CustomerType({
  name: { first: 'Val', last: 'Karpov' },
  email: '[email protected]'
});

const request = new RequestType({
  customer,
  createdAt: new Date()
});

// "RequestCustomerType { name: { first: 'Val', last: 'Karpov' } }"
console.log(request.customer);