Setting device-specific push notification token

set-token.js

const SET_PUSH_TOKEN = 'notifications.set.pushToken';
Meteor.methods({
  'notifications.set.pushToken'({token, os}) {
    check(arguments[0], {
      token: String,
      os: String,
    });

    const userId = this.userId;
    if (!userId) {
      throw new Meteor.Error(SET_PUSH_TOKEN, 'Must be logged in to set push notification token.');
    }

    Meteor.users.update(userId, {
      $addToSet: { pushToDevices: { token, os } },
    });
  },
});