{
    "bsonType": "object",
    "required": ["user_id", "article_id", "last_view_time", "first_view_time"],
    "permission": {
        "read": true, // 用户仅查看自己记录
        "create": "auth.uid != null", // 登录用户自动记录
        "update": "false", // 日志不可修改
        "delete": "'admin' in auth.role" // 仅管理员可删除
    },
    "properties": {
        "_id": {
            "description": "系统自动生成的文档ID",
            "bsonType": "string"
        },
		"user_id": {
		  "bsonType": "string",
		  "foreignKey": "uni-id-users._id",
		  "pattern": "^[0-9a-f]{24}$"
		},
		"article_id": {
		  "bsonType": "string",
		  "foreignKey": "uni-cms-articles._id",
		  "pattern": "^[0-9a-f]{24}$"
		},
        "first_view_time": {
            "bsonType": "timestamp",
            "description": "首次浏览时间",
            "defaultValue": {"$env": "now"},
            "errorMessage": "时间戳必须为有效数值"
        },
        "last_view_time": {
            "bsonType": "timestamp",
            "description": "最近浏览时间",
            "defaultValue": {"$env": "now"},
            "errorMessage": "时间戳必须为有效数值"
        }

    }
}