Google Calendar API: Calendar usage limits exceeded

Question

We have an application that does migrations between Google Apps domains. For calendar migrations we using Import API(https://developers.google.com/google-apps/calendar/v3/reference/events/import). For last six months we did a lot of calendar migrations. But about week ago we faced with new API error for import:

    "error"=>
  {"errors"=>[
    {"domain"=>"usageLimits",
    "reason"=>"quotaExceeded",
    "message"=>"Calendar usage limits exceeded."}], 
  "code"=>403, 
  "message"=>"Calendar usage limits exceeded."

Last week we got a lot of "Calendar usage limits exceeded." errors for users from different domains. Accordingly to Google API Console we didn't reach daily quota limit. For our app we using 2legged authorization.

Please help us understand what does "Calendar usage limits exceeded." mean? How we can prevent this error? Where we can find information about Calendar usage limits?

Answer 1

I found this official support document, and here's some brief info below, hope it helps: https://support.google.com/a/answer/2905486?hl=en

Calendar usage limits exceeded. This is the result of an API call. (Don't mix this up with the message "Daily quota exceeded," which points to insufficient API quota.)

If a user sees one of these messages it’s probably due to one of the following reasons:

• Creating too many events

If a user has created more than 10,000 events in his or her calendar within a short period of time, that user might lose calendar edit access.

• Creating too many calendars

If a user creates more than 25 new calendars within a short period of time, that user's calendar might go into read-only mode.

• Sending too many invitations or emails to external guests

In order to prevent spamming, Google Calendar limits the number of invitations a user can send to external guests. This limit varies depending on the action, and is usually between 100-300 guests.

Google Apps users can send invitations to any number of guests from their primary domain, or from secondary domains associated with their primary domain.

• Sharing calendars with too many users

If a user shares one or more calendars with many other users within a short period of time, Google Calendar might switch into read-only mode for that user. It’s almost impossible to reach this limit by updating sharing settings manually, but it can happen with some API-based tools or third-party apps.