Google Drive - 403 insufficient permission uploading file but not creating folder - ios

Question

I am trying to add Google Drive support to one of my apps using a private app data folder. I have sign-in working with the GIDSignIn class and the scope set to kGTLRAuthScopeDriveAppdata. Once I am signed in, I can create folders and get a file listing that shows the folders are there, then I can delete the folders and the file listing shows that they are gone. But for some reason when I try to upload a file I get a 403 error ("The user does not have sufficient permissions for this file."). This happens whether I try to put the file in the root of the app data folder or into a folder I have created.
I have set up a project in the Google Developer Console. I have an API key configured to work with my app's bundle ID and given it unrestricted API access. The Google Drive API is enabled.
My code is adapted from Google's own samples so a lot of this may look quite familiar. I've trimmed down the sign-in handling since that appears to be working fine.
- (instancetype) init
{
self = [super init];
if (!self) return nil;
[GIDSignIn sharedInstance].clientID = (NSString *)kGoogleClientId;
//kGoogleClientId is the ID from the developer console.
[GIDSignIn sharedInstance].delegate = self;
[GIDSignIn sharedInstance].scopes = #[kGTLRAuthScopeDriveAppdata];
return self;
}
//GIDSignInDelegate method
- (void) signIn:(GIDSignIn *)signIn didSignInForUser:(GIDGoogleUser *)user withError:(NSError *)error
{
authenticatedUser = user; //authenticatedUser is an instance variable
NSLog(#"Signed in to Google Drive with user %#", user.profile.name);
[delegate GoogleDriveDidSignIn:self];
}
- (GTLRDriveService *) driveService
{
static GTLRDriveService *service;
static dispatch_once_t onceToken;
dispatch_once(&onceToken,
^{
service = [[GTLRDriveService alloc] init];
service.APIKey = (NSString *)kGoogleApiKey;
//kGoogleApiKey matches the developer console too. It has unrestricted API access and is tied to my bundle ID
service.APIKeyRestrictionBundleID = [[NSBundle mainBundle] bundleIdentifier];
service.shouldFetchNextPages = YES;
service.retryEnabled = YES;
});
service.authorizer = authenticatedUser.authentication.fetcherAuthorizer;
//authenticatedUser is an instance variable which stores the user information returned by
//GIDSignIn when the user signs in
return service;
}
- (void) createFolderNamed:(NSString *)folderName completionHandler:(void(^)(NSString *foldername, NSString *newFolderId))completionHandler
{
GoogleDriveHandler * __weak weakself = self;
GTLRDriveService *service = [self driveService];
GTLRDrive_File *folder = [GTLRDrive_File object];
folder.name = folderName;
folder.mimeType = (NSString *)kMimeType_GoogleDriveFolder;
folder.parents = #[#"appDataFolder"];
GTLRDriveQuery_FilesCreate *query = [GTLRDriveQuery_FilesCreate queryWithObject:folder uploadParameters:nil];
[service executeQuery:query completionHandler:^(GTLRServiceTicket * _Nonnull callbackTicket, id _Nullable object, NSError * _Nullable callbackError)
{
if (callbackError)
{
NSLog(#"-createFolderNamed: callbackError: %#", callbackError.localizedDescription);
}
else
{
GTLRDrive_File *createdFolder = (GTLRDrive_File *)object;
if ( [createdFolder.mimeType isEqualToString:(NSString *)kMimeType_GoogleDriveFolder] )
{
NSLog(#"Google Drive created folder named \"%#\" with identifier \"%#\" and mime-type \"%#\"", createdFolder.name, createdFolder.identifier, createdFolder.mimeType);
}
else
{
NSLog(#"Error : Attempted to create folder, but Google Drive created item named \"%#\" with identifier \"%#\" and mime-type \"%#\"", createdFolder.name, createdFolder.identifier, createdFolder.mimeType);
}
}
}];
}
- (void) writeFileAtUrl:(NSURL *)source toFolderWithId:(NSString *)folderId completionHandler:(void(^)(NSString *filename, NSString *newFileId))completionHandler
{
GoogleDriveHandler * __weak weakself = self;
GTLRDriveService *service = [self driveService];
GTLRDrive_File *file = [GTLRDrive_File object];
file.name = source.lastPathComponent;
file.mimeType = #"binary/octet-stream";
file.parents = #[folderId];
file.spaces = #[#"appDataFolder"];
GTLRUploadParameters *parameters = [GTLRUploadParameters uploadParametersWithFileURL:source MIMEType:#"binary/octet-stream"];
parameters.shouldUploadWithSingleRequest = YES;
GTLRDriveQuery_FilesCreate *query = [GTLRDriveQuery_FilesCreate queryWithObject:file uploadParameters:parameters];
query.fields = #"id";
[service executeQuery:query completionHandler:^(GTLRServiceTicket * _Nonnull callbackTicket, id _Nullable object, NSError * _Nullable callbackError)
{
if (callbackTicket.statusCode == 200)
{
GTLRDrive_File *createdFile = (GTLRDrive_File *)object;
NSLog(#"Wrote file %# in Google Drive folder %#", createdFile.name, folderId);
if (completionHandler) completionHandler(createdFile.name, createdFile.identifier);
}
else
{
NSLog(#"-writeFileAtUrl:toFolderWithId:completionHandler: status code = %li : callbackError: %#", callbackTicket.statusCode, callbackError.localizedDescription);
}
}];
}
As an example, I've tried doing this after GIDSignIn logs in:
NSURL *sampleFile = [[NSBundle mainBundle] URLForResource:#"AValidTestFile" withExtension:#"png"];
if (sampleFile)
{
[self writeFileAtUrl:sampleFile toFolderWithId:#"appDataFolder" completionHandler:^(NSString *filename, NSString *newFileId)
{
NSLog(#"Uploaded file %# with ID %#", filename, newFileId);
}];
}
I still just get a 403 error.
At this point, I've read a huge number of tutorials, blog posts and forum threads in several different programming languages. I've gone over my own code several times and added an insane number of logging statements to double check everything, but I can't work out how I can have permission to create folders, but not to put files in them.
Some time later...
If you go through the credential wizard in the Google Console (rather than just selecting an iOS credential because you're creating an iOS app), you get a message which says "Application data cannot be accessed securely from iOS. Please consider selecting another platform" and it refuses to create a credential for you. Is it possible that this just doesn't work, despite the SDK having the necessary constants?

Answer 1

For those who follow after me, I think I've concluded that using the appDataFolder in iOS just doesn't work.
Having switched to using a folder in the Drive space, I've also found that the -uploadParametersWithFileURL:MIMEType: method of GTLRUploadParameters doesn't work. When I use that I get a file called 'Untitled' (containing the file metadata I set in my GTLRDrive_File object) in the root of the drive. As soon as I switched to -uploadParametersWithData:MIMEType: I got the correct file in the correct place.
I suppose the lesson so far is that if something isn't working, assume it’s the SDK.