group.json

{
  "$schema": "http://json-schema.org/draft-04/schema#",
  "title": "Group",
  "type": "object",
  "properties": {
    "_id":              {
                          "maxLength": 32,
                          "minLength": 2,
                          "pattern": "^[0-9a-z][0-9a-z.@_-]{0,30}[0-9a-z]$",
                          "title": "ID",
                          "type": "string"
                        },
    "created":          {},
    "modified":         {},
    "name":             {
                          "maxLength": 32,
                          "minLength": 2,
                          "pattern": "^[0-9A-Za-z][0-9A-Za-z .@_-]{0,30}[0-9A-Za-z]$",
                          "title": "Name",
                          "type": "string"
                        },
    "roles":            {
                          "type": "array",
                          "items": {"$ref": "permission.json"},
                          "title": "Roles",
                          "default": [],
                          "uniqueItems": true
                        }
  },
  "additionalProperties": false,
  "required": ["_id", "created", "modified"]
}