{
    "$schema": "http://json-schema.org/draft-04/schema#",
    "additionalProperties": false,
    "properties": {
        "username": {
            "type": "string"
        },
        "password": {
            "type": "string"
        },
        "roles": {
            "type": "array",
            "items": {
                "type": "string"
            }
        }
    },
    "required": [
        "username",
        "password",
        "roles"
    ],
    "type": "object"
}