Firebase push notification using node js and polymer web app

I want to send device push notification to android app,Here is what I am doing:
1. Created a webapp server(node js) and client code is written in polymer.
2. Deploying this webapp to android device as android app using some third party android container(Predix Mobile).
3. The third party container takes the web app and deployed it into android device as android app.
4. The third party web app doesn't have any plugin which can generate device token used to send device push notification using google firebase.
5. I have a login page in my web app ,when I login I want to generate the device token But I can't find any help how to do that , because my client code is written in Polymer .
6. I will send that token to my server code which will be deployed to cloud,the server will do a post call to push the notification to device.

Is there a way I can achieve this.

Thanks RV

via user3817378