Cloud Functions For Firebase - Send Fcm Message To Multiple Tokens

I have to send a message to many token when a node is created in my realtime database. I use that's code, but any notification are lost (people not receive its). exports.sendMessa

Solution 1:

This is how you send a FCM to an array of tokens:

returnPromise.all([admin.database().ref(`/users/${user}/account/tokensArray`).once('value')]).then(results => {
    const tokens = results[0];
    if (!tokens.hasChildren()) returnnull;
    let payload = {
      notification: {
        title: 'title',
        body: 'message',
        icon: 'icon-192x192.png'
      }
    };
    const tokensList = Object.keys(tokens.val());
    return admin.messaging().sendToDevice(tokensList, payload);
  });

Solution 2:

You can send notifications to an array of tokens. I am using this code to send notifications

return admin.messaging().sendToDevice(deviceTokenArray, payload, options).then(response => {
  console.log("Message successfully sent : " + response.successCount)
  console.log("Message unsuccessfully sent : " + response.failureCount)
});

I think you can find more information here https://firebase.google.com/docs/cloud-messaging/admin/legacy-fcm

Solution 3:

To return a Promise for all the send actions, modify your code to this:

return query.once("value")
      .then(function(snapshot) {
        var allPromises = [];
        snapshot.forEach(function(childSnapshot) {
          var user = childSnapshot.val();
          var token = user.token;
          var username = user.username;
          msg.message.token = token;
          const promise = admin.messaging().send(msg.message).then((response) => {
                console.log('message sent to '+username);
            }).catch((error) => {
                console.log(error);
            });
          allPromises.push(promise);              
      });
      returnPromise.all(allPromises);
    });