json-serializers

json-serializers: a simple DSL for defining JSON views

What is a json-serializer? A json-serializer allows you to map internal objects to external views.

Why use json-serializers

There are two common reasons for using json-serializers, consistency and security. By using serializers we ensure consistency to how objects are presented. Since attributes are whitelisted, this also increases security by limiting the chance of accidental internal value exposure.

Basic Example

The following example simply creates a new object that lacks the "password" field.

var user = {
  firstName: 'First',
  lastName: 'Last',
  email: '[e-mail]',
  password: 'password'
};

serializer.describe('user', function () {
    this.allow([ 'firstName', 'lastName', 'email' ]);
    this.deny('password');
});

var results = serializer.serialize('user', user);

results === {
  firstName: 'First',
  lastName: 'Last',
  email: '[e-mail]'  
}

Allowing and Denying

JSON serializers works as a combination whitelist/blacklist for object attributes where attributes must first be this.allow()'ed. this.deny() will always take priority in cases where an attribute is both allowed and denied.

var user = {
  firstName: 'First',
  lastName: 'Last',
  email: '[e-mail]',
  password: 'password'
};

serializer.describe('user', function () {
    this.allowAll();
    this.deny('password');
});

var results = serializer.serialize('user', user);

results === {
  firstName: 'First',
  lastName: 'Last',
  email: '[e-mail]'  
}

Nested Objects

Serializers can also be nested using this.reference().

var user = {
  firstName: 'First',
  lastName: 'Last',
  email: '[e-mail]',
  password: 'password',
  address: {
    street: '1234 Example',
    city: 'Indianapolis',
    state: 'IN'
  }
};

serialize.describe('user.address', function() {
  this.allow('state');
});

serializer.describe('user', function() {
    this.allow([ 'firstName', 'lastName', 'email', 'address' ]);
    this.deny('password');
    this.reference('address', 'user.address');
});

var results = serializer.serialize('user', user);

results === {
  firstName: 'First',
  lastName: 'Last',
  email: '[e-mail]',
  address: {
    state: 'IN'
  }
}