Is it possible to grant a JavaScript app, r/w permission to a Google Sheets file, without the need for the app user to log in/have a Google account?

Question

I have a Google Spreadsheet file and a JavaScript application, hosted using Google Firebase free plan – if that changes anything. I would like to grant my application a read/write permission to the file so that when a user, posts something using my app, it will be written to the SpreadSheet as a new line. I thought that should be a simple scenario but…

While I got the read part running, using the API_KEY , the writing part seems to require OAuth authentication - even if the file itself is 100% public…

In my scenario the application itself should be the one, authenticating to the Sheet API - not the user of that application.

So, is there any way around this? Or to somehow log-in using OAuth on the application level?

Please note: I know I could use Firebase here, but let's just assume that for now, it is not an option.

Answer 1

My final solution was to use Google Apps Script instead of Google Sheets API, as described here:

https://stackoverflow.com/a/49459945/2384366

After publishing the scrip with the ' Who has access to the app ' = ' Anyone, even anonymous ' – I was able to use the doPost function to do exactly what I wanted.

Perhaps it's not the best solutions – but it works (and frankly, gives us much more control).