javascript - 尝试订阅 Firebase Cloud Messaging 主题时出现错误

Question

当我尝试订阅某个主题时，出现以下错误:

.subscribeToTopic is not a function

const messaging = firebase.messaging();
      messaging
        .requestPermission()
        .then(() => {
          return messaging.getToken();
        })
        .then(token => {
          messaging
            .subscribeToTopic(token, 'allUsers')
            .then(response=> {
              console.log(JSON.stringify(response));
            })
            .catch(function(error) {
              console.log('Error subscribing to topic:', error);
            });
        })
        .catch(err => {
          console.log('Unable to get permission to notify.', err);
        });

如果我删除该行 .subscribeToTopic 并通过 http 添加 POST 调用，则可以使用以下 url:<强> https://iid.googleapis.com/iid/v1/TOKEN/rel/topics/TOPIC_NAME

我查看了这个问题和文档 Cloud Messaging in Cloud Functions: admin.messagin(...).send is not a function

https://firebase.google.com/docs/cloud-messaging/js/topic-messaging

Answer 1

啊，我通过在后端(nodeJS)处理来解决这个问题，其中文档很容易处理主题。

所以在这种情况下，我们在前端生成 token 然后在后端(nodeJS)我们尝试通过 token 订阅主题。

因此，当我们流式传输或 firebase.messaging().onMessage(payload => {) 时，在前端希望按主题触发并显示消息。

仅供引用:https://github.com/firebase/firebase-js-sdk/issues/5289#issuecomment-899542765

所以从链接我们知道Notification.vue

// these from frontend side ( for example vueJS )
import firebase from 'firebase/app'
import 'firebase/messaging'
// firebase only for get token, onMessaging, request permission check, there is no function to subscribe topic by the token, so we handle on backend side my alternative

然后在server.js

// these from backend side ( for examle nodeJS )
const { admin } = require('./firebase-config');
// admin.messaging().sendToTopic()
// admin.messaging().subscribeToTopic()
// admin.messaging().sendToDevice()

如果您正在寻找firebase-config.js，这里是

/*
 * Initialize firebase
 */
var admin = require("firebase-admin");

var serviceAccount = require("./firebase.json"); // you can get the .json file on firebase service account .

admin.initializeApp({
  credential: admin.credential.cert(serviceAccount),
  databaseURL: "https://project-xxxxxxx.firebaseio.com"
});
module.exports.admin = admin

我的实现:

app.get('/firebase/notification', (req, res)=>{
  const registrationToken = req.body.registrationToken;

  admin.messaging().subscribeToTopic(registrationToken, 'myTopic')
      .then(response => {
        console.log('Successfully subscribed to topic:', response)

        const options =  notification_options;
        const message_notification = {
          notification: {
            title: 'Yogi Arif Widodo',
            body: '2 10 pm',
            url: 'https://localhost:8080',
            other: 'other data',
          }
        };
        admin.messaging().sendToTopic('myTopic', message_notification, options).then( response => {

所以当我在 firebase 控制台上测试按主题 myTopic 发送时，我的 Notification.vue 触发了这些代码

firebase.messaging().onMessage(payload => {
.....console.log
}