Using Google Cloud Print to print to a designated printer in a restaurant from an app

The restaurant I'm working with has a pos printer in their brick and mortar building. So when a user makes a purchase on the app, we're using square as a payment processor, I'd like to use google cloud print to send a job to that printer in the restaurant itself. Using google cloud print though you seem to need the user using the app to sign in to google first and that wouldn't make any sense in the flow of the app because it's not a user printer we're sending a job to. I'm using node.js and parse-server on the backend and this will be implemented in iOS and Android apps.

The flow is as follows:

1. Your client need to have a Google Account (gmail)
2. Your client need to add the printer in to their Google Account. If the printer supports by default this option, then they have to follow the instruction included on the printer. If the printer doesn't support Google Print then their have to install Chrome on the computer that the printer is connected, add the printer to the system, and add the printer to Google Print. They can follow this instruction.
3. Once they have the printer added to their account they can decide who can have access to their printers.

How to gain access to the client printer

1. In your app that you are building for them, you have to have a button that allows them to grant access to their printers to your app using OAuth 2.0.
2. Once they grant access to your app, you will be able to manage their printers on their behalf.

I hope this helps :)