3 "description": "required validation",
6 "foo": {"required" : true},
12 "description": "present required property is valid",
17 "description": "non-present required property is invalid",
24 "description": "required default validation",
32 "description": "not required by default",
39 "description": "required explicitly false validation",
42 "foo": {"required": false}
47 "description": "not required if required is false",