firebase 功能将通知推送给特定用户

Question

当其他用户喜欢他/她的帖子时，我想通过 firebase 功能向发布帖子的用户发送推送通知。

i want to get the highlighted user-id in the image to get fcm token of this user id stored in other tree.

下面是我的firebase函数代码。

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


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


exports.sendNotification = functions.database.ref('/user-posts/{userID}/{pushId}/stars/')
        .onWrite(event=> {
            var request = event.data.val();

            console.log("request",request);
            console.log("key",Object.keys(request)[0]);
            var key = Object.keys(request)[0];
            var token;




            const payload = {
          notification: {
            title: 'You have a new follower!',
            body: 'is now following you.'
          }
        };



             const getDeviceTokensPromise = admin.database()
             .ref(`/users-notifications/${key}`)
             .once('value').then(function(snapshot) {
                    console.log("val",snapshot.val());
                        token= snapshot.val();


                        admin.messaging().sendToDevice(token,payload)
            .then(response=>{
                console.log("Successfully sent message:", response);

            })
            .catch(function(error){
                console.log("error sending message",error);
            })
        })

                    }, function(error) {
                        // The Promise was rejected.
                    console.error(error);
                    });

Answer 1

您可以使用事件引用的父属性向后遍历 DB 树。

userID = event.data.ref.parent.parent.parent.key

event.data.ref 的父级是“星星” “stars”的父级是您的 pushID pushID 的父级是 userID

Answer 2

尝试使用event.params.userID从uri中提取它