I've exposed a few APIs using go-endpoints. The APIs work fine, but what I'd like to do is restrict usage of the APIs to only a few referers. Since I'm not passing any authentication information, I do not need OAuth (actually, I really do not want to use OAuth as I expect anonymous users to utilize a front-end that uses this API... I just want that front-end and perhaps another one to use my API).
Apparently the way to do this is to make a Public API Key using the Google Developers Console (Project --> APIs and auth --> Credentials --> Create new Key).
I've changed my JavaScript to use this key, by passing it as a param: https://my-app-id.appspot.com/_ah/api/myService/v1/doSomething?key=key_from_developer_console
However, when I make the call, I get a 403 back with this error:
"Access Not Configured. The API () is not enabled for your project. Please use the Google Developers Console to update your configuration."
Well, initially I set the referer to my-app-id.appspot.com/*, which is only place I want my API to be used from. So I figured I'd remove it just to see, but I get the same issue.
There are some old posts here about having to enable Contacts API and Google + API. I tried that, and it didn't work either.
So what gives? There is virtually no documentation from Google on this Public API Key feature. This is really driving me up a wall...