$.post('https://script.google.com/macros/s/AKfycbzUqz44wOat0DiGjRV1g..., data)
... how does the security work on that, or can I RSVP to your wedding too?
How does the "RSVP to google sheets" work?
1. Create 'google forms' one-page survey, gathering outputs into a spreadsheet.
2. Use browser debug tools to figure out form field names, which will be things like 'entry.1150050082'
3. curl "https://docs.google.com/forms/d/ 1xFOZk3D1...wnIjGAf0/formResponse?ifq&entry.1150050082=FOO&entry.1477423851=BAR&entry.592766186=BAZ&submit=Submit" or the appends a row to the google sheet with the values FOO, BAR and BAZ.
I assume if your site embedded a form that sent the same request as that curl query, it would do the same thing.
Obviously, this isn't going to win you any awards for highly maintainable professional design at work. But if you want something quick and you aren't fussed about whether it works a year from now, it can get the job done.
It would be quite easy to check the rsvp code in appscript. E.g. have a sheet with all the guests, and give a random number (rsvp code) to each guest. Then on each rsvp request you could check whether that rsvp code exists in the code column. If yes: you'll add the answer to that row. If no: return an error.
You can store the code in a particular box in the sheet and then your google script can validate the code entered by the guest.
However, due to timing constraints, I couldn't do this and instead used a simple encryption algorithm to have the hacker at least put in some effort to know the invite code :)
I will raise an issue on github for this.