如何创建Firebase规则以检查用户属性

Question

我在Firebase中为节点添加了一些自定义属性。就像;

{
  "user" : {
    "UID11" : {
      "address" : "address of user 1",
      "siteLink" : "site1",
      "subSiteLink" : "subsite1",  
    },
    "UID12" : {
      "address" : "address of user 2",
      "siteLink" : "site1"  
      "subSiteLink" : "subsite2",  
    }
    "UID21" : {
      "address" : "address of user 2",
      "siteLink" : "site2"  
      "subSiteLink" : "subsite2",  
    }
  }
}

并且，有站点节点。就像;

{
  "site1" : {
     "subsite1" : {
         "someproperty" : "somevalue",
         "someproperty2" : "someValue"
      },
      "subsite2" : {
         "someproperty" : "somevalue",
         "someproperty2" : "someValue"
      },
      "general1" : {
         "someproperty" : "somevalue",
         "someproperty2" : "someValue"
      },
      "general2" : {
         "someproperty" : "somevalue",
         "someproperty2" : "someValue"
      }
    }

   "site2" : {
     "subsite1" : {
         "someproperty" : "somevalue",
         "someproperty2" : "someValue"
      },
      "subsite2" : {
         "someproperty" : "somevalue",
         "someproperty2" : "someValue"
      },
      "general1" : {
         "someproperty" : "somevalue",
         "someproperty2" : "someValue"
      },
      "general2" : {
         "someproperty" : "somevalue",
         "someproperty2" : "someValue"
      }
    }
}

现在，我想创建一些规则。用户只能访问自己的子站点，并且只能访问用户有权访问的站点中的常规*节点。以下是根据上述信息的示例;

UID11 可以访问 site1.subsite1，site1.general1，site1.general2 。
UID12 可以访问 site1.subsite2，site1.general1，site1.general2 。
UID21 可以访问 site2.subsite1，site2.general1，site2.general2 。

如何创建这些规则？