title: How to send data payload to all the users using Firebase Cloud Messaging?
body: <p>I want to send some message using Firebase Cloud Messaging service to all my users who are using the app. I can send data payload to a single or multiple devices using <code>regisration_ids</code> like this :</p>
  
  <pre><code>{
  
      "data": {
        "body":"body",
          "my_custom_key" : "215",
          "other_key" : true
       },
             "registration_ids": ["dCmhVkVMmLw:APA91bE5.."]
  
  }
  </code></pre>
  
  <p>But how do I send data payload to all the users?</p>