NextPageToken and File List queries - objective-c

Question

I'm using the GoogleDrive Objective-C SDK, and I'm running into an issue. I want to build up a path -> ID mapping structure, so I ask Drive for a list of all of a users files. Normally this works fine. But, in cases where users have very large amounts of files, the server returns an internal error. I can fix this by setting the maxResults property on my GTLQueryDrive to a lower number. When I do that, everything works as expected, EXCEPT that the nextPageToken (and nextLink) property of the GTLDriveFileList is nil. I believe I need this nextPageToken to continue grabbing file information. I have tried setting the fields property on my query to nil, to a string that includes nextPageToken, and to a string that does not include nextPageToken. The nextPageToken property appears to be nil in all cases. Is there something I am missing? Thanks!

Answer 1

Adding answer based on comment chain.
Here's a little sample that you can experiment with.
driveService.shouldFetchNextPages = YES;
GTLQueryDrive *query = [GTLQueryDrive queryForFilesList];
query.maxResults = 5;
// queryTicket can be used to track the status of the request.
[driveService executeQuery:query
completionHandler:^(GTLServiceTicket *ticket, GTLDriveFileList *files,
NSError *error) {
if (files) {
NSLog(#"Have response %#", files.items);
NSLog(#"Token %#", files.nextPageToken);
NSLog(#"Count %d", files.items.count);
}
}];
With shouldFetchNextPages set to YES, the result will not contain a nextPageToken. Instead, assuming you have more than 5 files (based on maxResults) you'll still get the full list, along with a message in the log file that will look something along the lines of:
Executing drive.files.list required fetching 4 pages; use a query with a larger maxResults for faster results
If you set shouldFetchNextPages to NO, the result will be capped at 5 results in this case, and nextPageToken will have a valid token for getting the next page in the result set.