[android] How do you send a Firebase Notification to all devices via CURL?

I'm attempting to send out a notification to all app users (on Android), essentially duplicating what happens when a notification is sent via the Firebase admin console. Here is the CURL command I begin with:

curl --insecure --header "Authorization: key=AIzaSyBidmyauthkeyisfineL-6NcJxj-1JUvEM" --header "Content-Type:application/json" -d "{\"notification\":{\"title\":\"note-Title\",\"body\":\"note-Body\"}}" https://fcm.googleapis.com/fcm/send

Here's that JSON parsed out to be easier on your eyes:

{
"notification":{
    "title":"note-Title",
    "body":"note-Body"
    }
}

The response that comes back is just two characters:

to

That's it, the word "to". (Headers report a 400) I suspect this has to do with not having a "to" in my JSON. What would one even put for a "to"? I have no topics defined, and the devices have not registered themselves for anything. Yet, they are still able to receive notifications from the Firebase admin panel.

I'm want to attempt a "data only" JSON package due to the amazing limitation of Firebase notification processing whereby if your app is in the foreground, the notification gets processed by YOUR handler, but if your app is in the background, it gets processed INTERNALLY by the Firebase service and never passed to your notification handler. APPARENTLY this can be worked around if you submit your notification request via the API, but ONLY if you do it with data-only. (Which then breaks the ability to handle iOS and Android with the same message.) Replacing "notification" with "data" in any of my JSON has no effect.

Ok, then I attempted the solution here: Firebase Java Server to send push notification to all devices which seems to me to say "Ok, even though notifications to everyone is possible via the Admin console... it's not really possible via the API." The workaround is to have each client subscribe to a topic, and then push out the notification to that topic. So first the code in onCreate:

FirebaseMessaging.getInstance().subscribeToTopic("allDevices");

then the new JSON I send:

{
"notification":{
    "title":"note-Title",
    "body":"note-Body"
    },
"to":"allDevices"
}

So now I'm getting a real response from the server at least. JSON response:

{
"multicast_id":463numbersnumbers42000,
"success":0,
"failure":1,
"canonical_ids":0,
"results":
    [
    {
    "error":"InvalidRegistration"
    }
    ]
}

And that comes with a HTTP code 200. Ok... according to https://firebase.google.com/docs/cloud-messaging/http-server-ref a 200 code with "InvalidRegistration" means a problem with the registration token. Maybe? Because that part of the documentation is for the messaging server. Is the notification server the same? Unclear. I see elsewhere that the topic might take hours before it's active. It seems like that would make it useless for creating new chat rooms, so that seems off as well.

I was pretty excited when I could code up an app from scratch that got notifications in just a few hours when I had never used Firebase before. It seems like it has a long way to go before it reaches the level of, say, the Stripe.com documentation.

Bottom line: does anyone know what JSON to supply to send a message out to all devices running the app to mirror the Admin console functionality?

The answer is


Your can send notification to all devices using "/topics/all"

https://fcm.googleapis.com/fcm/send
Content-Type:application/json
Authorization:key=AIzaSyZ-1u...0GBYzPu7Udno5aA

{
  "to": "/topics/all",
  "notification":{ "title":"Notification title", "body":"Notification body", "sound":"default", "click_action":"FCM_PLUGIN_ACTIVITY", "icon":"fcm_push_icon" },
  "data": {
    "message": "This is a Firebase Cloud Messaging Topic Message!",
   }
}

For anyone wondering how to do it in cordova hybrid app:

  • go to index.js -> inside the function onDeviceReady() write :

      subscribe();
    

(It's important to write it at the top of the function!)

  • then, in the same file (index.js) find :

    function subscribe(){

     FirebasePlugin.subscribe("write_here_your_topic", function(){
    
     },function(error){
    
         logError("Failed to subscribe to topic", error);
     });
     }
    

and write your own topic here -> "write_here_your_topic"


One way to do that is to make all your users' devices subscribe to a topic. That way when you target a message to a specific topic, all devices will get it. I think this how the Notifications section in the Firebase console does it.


I was looking solution for my Ionic Cordova app push notification.

Thanks to Syed Rafay's answer.

in app.component.ts

const options: PushOptions = {
  android: {
    topics: ['all']
  },

in Server file

"to" => "/topics/all",

Check your topic list on firebase console.

  1. Go to firebase console

  2. Click Grow from side menu

  3. Click Cloud Messaging

  4. Click Send your first message

  5. In the notification section, type something for Notification title and Notification text

  6. Click Next

  7. In target section click Topic

  8. Click on Message topic textbox, then you can see your topics (I didn't created topic called android or ios, but I can see those two topics.

  9. When you send push notification add this as your condition.

    "condition"=> "'all' in topics || 'android' in topics || 'ios' in topics",

Full body

array(
    "notification"=>array(
        "title"=>"Test",
        "body"=>"Test Body",
    ),
    "condition"=> "'all' in topics || 'android' in topics || 'ios' in topics",
);

If you have more topics you can add those with || (or) condition, Then all users will get your notification. Tested and worked for me.


Firebase Notifications doesn't have an API to send messages. Luckily it is built on top of Firebase Cloud Messaging, which has precisely such an API.

With Firebase Notifications and Cloud Messaging, you can send so-called downstream messages to devices in three ways:

  1. to specific devices, if you know their device IDs
  2. to groups of devices, if you know the registration IDs of the groups
  3. to topics, which are just keys that devices can subscribe to

You'll note that there is no way to send to all devices explicitly. You can build such functionality with each of these though, for example: by subscribing the app to a topic when it starts (e.g. /topics/all) or by keeping a list of all device IDs, and then sending the message to all of those.

For sending to a topic you have a syntax error in your command. Topics are identified by starting with /topics/. Since you don't have that in your code, the server interprets allDevices as a device id. Since it is an invalid format for a device registration token, it raises an error.

From the documentation on sending messages to topics:

https://fcm.googleapis.com/fcm/send
Content-Type:application/json
Authorization:key=AIzaSyZ-1u...0GBYzPu7Udno5aA

{
  "to": "/topics/foo-bar",
  "data": {
    "message": "This is a Firebase Cloud Messaging Topic Message!",
   }
}

Just make all users who log in subscribe to a specific topic, and then send a notification to that topic.


The most easiest way I came up with to send the push notification to all the devices is to subscribe them to a topic "all" and then send notification to this topic. Copy this in your main activity

FirebaseMessaging.getInstance().subscribeToTopic("all");

Now send the request as

{
   "to":"/topics/all",
   "data":
   {
      "title":"Your title",
      "message":"Your message"
      "image-url":"your_image_url"
   }
}

This might be inefficient or non-standard way, but as I mentioned above it's the easiest. Please do post if you have any better way to send a push notification to all the devices.

You can follow this tutorial if you're new to sending push notifications using Firebase Cloud Messaging Tutorial - Push Notifications using FCM


To send a message to a combination of topics, specify a condition, which is a boolean expression that specifies the target topics. For example, the following condition will send messages to devices that are subscribed to TopicA and either TopicB or TopicC:

{
   "data":
   {
      "title": "Your title",
      "message": "Your message"
      "image-url": "your_image_url"
   },
   "condition": "'TopicA' in topics && ('TopicB' in topics || 'TopicC' in topics)"
}

Read more about conditions and topics here on FCM documentation


Examples related to android

Under what circumstances can I call findViewById with an Options Menu / Action Bar item? How to implement a simple scenario the OO way My eclipse won't open, i download the bundle pack it keeps saying error log getting " (1) no such column: _id10 " error java doesn't run if structure inside of onclick listener Cannot retrieve string(s) from preferences (settings) strange error in my Animation Drawable how to put image in a bundle and pass it to another activity FragmentActivity to Fragment A failure occurred while executing com.android.build.gradle.internal.tasks

Examples related to firebase

How can I solve the error 'TS2532: Object is possibly 'undefined'? Getting all documents from one collection in Firestore FirebaseInstanceIdService is deprecated Failed to resolve: com.google.firebase:firebase-core:16.0.1 NullInjectorError: No provider for AngularFirestore Firestore Getting documents id from collection How to update an "array of objects" with Firestore? firestore: PERMISSION_DENIED: Missing or insufficient permissions Cloud Firestore collection count iOS Swift - Get the Current Local Time and Date Timestamp

Examples related to firebase-cloud-messaging

FirebaseInstanceIdService is deprecated Error: fix the version conflict (google-services plugin) How do you send a Firebase Notification to all devices via CURL? No notification sound when sending notification from firebase in android FCM getting MismatchSenderId Firebase (FCM) how to get token How to handle notification when app in background in Firebase What is FCM token in Firebase? Firebase FCM force onTokenRefresh() to be called Send push to Android by C# using FCM (Firebase Cloud Messaging)

Examples related to firebase-notifications

How do you send a Firebase Notification to all devices via CURL? What is FCM token in Firebase? Firebase FCM notifications click_action payload