How do you check if a domain has enabled the GData Provisioning API without trying to modify the domain?
The only way I have been able to find that will give an API failure response is doing something like trying to create a new user. This is obviously a terrible way.
The response when I request access through OAuth is the same independent of whether they have checked the domain setting. Get requests (like getting the domain's list of users) does not require this setting being enabled.