javascript - 在 onwrite 事件中查询 firebase 数据库

Question

我正在尝试编写一个 firebase 函数，它将检查“用户”并根据数据库写入事件进行行为。但是，当我查询数据库时，它每次都返回 null，而且我不知道我做错了什么。如有任何帮助，我们将不胜感激。

提前致谢。

我的实时数据库结构是这样的:

ilk-projemiz-cd55baddclose
 users
   edRIPg8BcZU9YPbubp7HtQo7phl1
     sayilar: 1532
     status:  "on"
   hakan
     sayilar:  5000
     status:  "waiting"
   mehmet
     sayilar:  7000
     status:  "on"

我的 firebase 函数文件是这样的:

const functions = require('firebase-functions');
const admin = require('firebase-admin');

exports.sayi = functions.database.ref("/users/{uid}/status").onWrite(event => {
    const status = event.data.val();
    var user = event.data.ref.parent.key;
    if (status =="on") {
        console.log(status);
        const events = event.data.adminRef.child('users');
        const query =events.orderByChild('status').equalTo('on').limitToFirst(2);
        query.on("value", sorunsuz,sorunlu);
    }
});

function sorunlu(error) {
    console.log("Something went wrong.");
    console.log(error);
}

function sorunsuz(data) {
    console.log("11111");
    var fruits = data.val();
    console.log(fruits); //it returns null here
    var keys = Object.keys(fruits);
    for (var i = 0; i < keys.length; i++) {
      var key = keys[i];
      if(key==user){
        //console.log(fruits[key].sayilar);
        console.log("aaa");
      }else{
        console.log("bbbb");
      }
    }
}

Answer 1

这一行:const events = event.data.adminRef.child('users');尝试访问 users status下的节点节点。我认为您想要做的是访问根引用下的用户节点。

改用管理 SDK:

const events = admin.database().child('users');

更新:user变量超出范围，所以我建议您移动 sorunsuz()函数位于 on() 内功能:

const functions = require('firebase-functions');
const admin = require('firebase-admin');
admin.initializeApp(functions.config().firebase);

exports.sayi = functions.database.ref("/users/{uid}/status").onWrite(event => {
    const status = event.data.val();
    var user = event.data.ref.parent.key;
    if (status =="on") {
        console.log(status);
        const events = admin.database().child('users');
        const query =events.orderByChild('status').equalTo('on').limitToFirst(2);
        query.on("value",
         function(data) {
            console.log("11111");
            var fruits = data.val();
            console.log(fruits); //it returns null here
            var keys = Object.keys(fruits);
            for (var i = 0; i < keys.length; i++) {
                var key = keys[i];
                if(key==user){
                    //console.log(fruits[key].sayilar);
                    console.log("aaa");
                }else{
                    console.log("bbbb");
                }
            }
        }, sorunlu);
    }
});

function sorunlu(error) {
    console.log("Something went wrong.");
    console.log(error);
}