Google Calendar API yielding "Quota Exceeded" error, but quota limit has not been reached

Question

I'm using the Google Calendar API v3 from the Python client. The courtesy limit is 10,000 queries per day. The Google API Console shows that I've used up 471 requests so far today and a total of 1.47k over the last 28 days, which sounds like it is far short of the limit.

I am now seeing HTTP Error 403 Quota Exceeded errors every time I try to use the API. I'm aware there is also a rate limit, but I'm not sending requests particularly fast and I've reset the per-user rate limit to 10,000 requests/second/user using the API Console just to be safe. I'm probably generating less than 5 requests per second, from one instance of a single-threaded application that no one else has access to during development. I've tried sleeping and retrying the query but I get the same error every time I retry.

Is there some other quota (besides the 10,000 requests per day and the per user rate limit) that I am running up against? Is Google's quota system broken?

Thanks for your help.

Answer 1

It appears that the Google Calendar API has an undocumented limit on the number of new calendars that can be created in a given period of time. The limit is very low, often around 20 or 30. By the next day, I can make another batch of calendars.

We're trying to create a class calendar for everyone in a school, and now it will take days, if not weeks, to create all of the calendars.

Once the calendars are created, then the normal API limits apply.