Typescript 如何使用FCM将通知从一台计算机发送到另一台使用Angular2的计算机

如何向登录到我的站点的用户发送通知。 如何使用angular2、typescript为系统或设备生成fcmtoken。 请帮我解决这个问题。如果有人有任何想法，请告诉我

 import { Injectable }          from '@angular/core';
import { AngularFireDatabase } from 'angularfire2/database';
import { AngularFireAuth }     from 'angularfire2/auth';
import * as firebase from 'firebase';
import 'rxjs/add/operator/take';
import { BehaviorSubject } from 'rxjs/BehaviorSubject'
import { Observable } from 'rxjs/Observable';
import { Http, Response } from '@angular/http';
import { Headers, RequestOptions } from '@angular/http';

@Injectable()

export class MessagingService {
  messaging = firebase.messaging()
  currentMessage = new BehaviorSubject(null)
  constructor(private db: AngularFireDatabase, private afAuth: AngularFireAuth) { }
  updateToken(token) {
    this.afAuth.authState.take(1).subscribe(user => {
      if (!user) return;
      const data = { [user.uid]: token }
      this.db.object('fcmTokens/').update(data)


    })
  }


  getPermission() {
    this.messaging.requestPermission()
    .then(() => {
      console.log('Notification permission granted.');
      return this.messaging.getToken()
    })
    .then(token => {
      console.log(token)
     // this.updateToken(token)
    })
    .catch((err) => {
      console.log('Unable to get permission to notify.', err);
    });
  }


  receiveMessage() {
    this.messaging.onMessage((payload) => {
     console.log("Message received. ", payload);
     this.currentMessage.next(payload)
   });
 }




}

我正在创建服务MessagingService.ts以帮助此网站

但这是给定的错误 连接后端没有提供程序

我解决了这个问题

创建用于调用nodejs云函数的消息API服务

import { Injectable }          from '@angular/core';
import { AngularFireDatabase } from 'angularfire2/database';
import { AngularFireAuth }     from 'angularfire2/auth';
import * as firebase from 'firebase';

import 'rxjs/add/operator/take';
import { BehaviorSubject } from 'rxjs/BehaviorSubject'

@Injectable()
export class MessagingService {

  messaging = firebase.messaging()
  currentMessage = new BehaviorSubject(null)

  constructor(private db: AngularFireDatabase, private afAuth: AngularFireAuth) { }


  updateToken(token) {
    this.afAuth.authState.take(1).subscribe(user => {
      if (!user) return;

      const data = { [user.uid]: token }
      this.db.object('fcmTokens/').update(data)
    })
  }

  getPermission() {
      this.messaging.requestPermission()
      .then(() => {
        console.log('Notification permission granted.');
        return this.messaging.getToken()
      })
      .then(token => {
        console.log(token)
        this.updateToken(token)
      })
      .catch((err) => {
        console.log('Unable to get permission to notify.', err);
      });
    }

    receiveMessage() {
       this.messaging.onMessage((payload) => {
        console.log("Message received. ", payload);
        this.currentMessage.next(payload)
      });

    }
}

上述来自component.ts文件的服务调用

ngOnInit() {
    this.msgService.getPermission()
    this.msgService.receiveMessage()
    this.message = this.msgService.currentMessage
  }

index.js Nodejs后端从消息服务获取输入

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

exports.fcmSend = functions.database.ref('/messages/{userId}/{messageId}').onCreate(event => {


  const message = event.after.val()
  const userId  = event.params.userId

  const payload = {
        notification: {
          title: message.title,
          body: message.body,
          icon: "https://placeimg.com/250/250/people"
        }
      };


   admin.database()
        .ref(`/fcmTokens/${userId}`)
        .once('value')
        .then(token => token.val() )
        .then(userFcmToken => {
          return admin.messaging().sendToDevice(userFcmToken, payload)
        })
        .then(res => {
          console.log("Sent Successfully", res);
        })
        .catch(err => {
          console.log(err);
        });

});

每当使用onCreate（）触发器在数据库中创建新消息时。云函数将首先提取我们保存在数据库中的FCM令牌，然后使用消息数据创建将发送给最终用户的有效负载

现在部署nodejs函数

firebase deploy --only functions