rules.json

{
    "rules": {
        "shorts": {
            "$query": {
                "remark": {
                    ".read": true,
                    ".write": true,
                    ".validate": "newData.isString() && newData.val().length <= 100"
                },
                "slug": {
                    ".read": true,
                    ".write": true,
                    ".validate": "newData.isString() && newData.val().length >= 4 && newData.val().length <= 10 && newData.val().matches(/^[a-zA-Z0-9]+$/)"
                },
                "url": {
                    ".read": true,
                    ".write": true,
                    ".validate": "newData.isString() && newData.val().matches(/^(https|http|ftp):\\/\\//) && newData.val().length <= 255"
                },
                "timestamp": {
                    ".read": true,
                    ".write": true,
                    ".validate": "newData.isNumber() && now - newData.val() < 30000"
                },
                "user": {
                    "ua": {
                        ".read": true,
                        ".write": true,
                        ".validate": "newData.isString() && newData.val().length <= 255"
                    },
                    "country": {
                        ".read": true,
                        ".write": true,
                        ".validate": "newData.isString() && newData.val().length <= 96"
                    },
                    "ip": {
                        ".read": true,
                        ".write": true,
                        ".validate": "newData.isString() && (newData.val().matches(/^((25[0-5]|2[0-4]\\d|[01]?\\d\\d?)\\.){3}(25[0-5]|2[0-4]\\d|[01]?\\d\\d?)$/) || newData.val().matches(/^([\\da-fA-F]{1,4}:){7}[\\da-fA-F]{1,4}$/))"
                    },
                    ".validate": "newData.hasChildren(['country', 'ip', 'ua'])"
                },
                ".read": true,
                ".write": true,
                ".indexOn": [
                    "timestamp"
                ],
                ".validate": "newData.hasChildren(['url','slug','timestamp','remark','user'])"
            },
            ".read": "auth.uid !== null",
            ".write": "auth.uid !== null"
        }
    }
}