apps.groups.migration return HTTP error 500

Question

I am trying to import existing mail content to a google group through apps.groups.migration API. The code is in C++ and the protolol is nakid HTTP. The program fails with HTTP error 500.

Following is the error response contents and header. What is wrong ?

{
 "error": {
  "errors": [

{ "domain": "global", "reason": "backendError", "message": "Backend Error" } ], "code": 500, "message": "Backend Error" } }

Alternate-Protocol: 443:quic Content-Length: 177 Content-Type: application/json Date: Thu, 02 Jan 2014 06:50:10 GMT Server: HTTP Upload Server Built on Dec 11 2013 18:21:10 (1386814870)

Answer 1

Backend Errors are a normal part of working with Google APIs and generally indicate that your application is sending data to Google to fast and needs to backoff some. See the details in the Group Migration API Limits document. Further details about implementing exponential backoff are offered in the Drive API docs.

You may want to take a look at the Google APIs Client Library for C++ rather than reinventing the wheel for these interactions.