firebase-functions-pushnotification

How?

1. Set up Node.js

   Download Node.js from https://nodejs.org/en/

2. Set up Firebase CLI

    $ npm install -g firebase-tools
   

3. Initialize Firebase SDK for Cloud Functions

    $ firebase login
    $ firebase init functions
   

4. Paste the following code to functions/index.js

    //import firebase functions modules
    const functions = require('firebase-functions');
   
    //import admin module
    const admin = require('firebase-admin');
    admin.initializeApp(functions.config().firebase);
   
   
    // Listens for new messages added to messages/:pushId
    exports.pushNotification = functions.database.ref('/messages/{pushId}').onWrite( event => {
   
        console.log('Push notification event triggered');
   
        //  Grab the current value of what was written to the Realtime Database.
        var valueObject = event.data.val();
   
        if(valueObject.photoUrl != null) {
          valueObject.photoUrl= "Sent you a photo!";
        }
   
      // Create a notification
        const payload = {
            notification: {
                title:valueObject.msgUser,
                body: valueObject.msgText || valueObject.photoUrl,
                sound: "default"
            },
        };
   
      //Create an options object that contains the time to live for the notification and the priority
        const options = {
            priority: "high",
            timeToLive: 60 * 60 * 24
        };
   
   
        return admin.messaging().sendToTopic("pushNotifications", payload, options);
    });
   

5. Deploy the function

   $ firebase deploy