Insufficient Permission error for Google Drive iOS - ios

Question

I am using Google SignIn for authentication in one of my iOS application. With that I am defining all possible scopes for Google drive use but still getting the following error. I am creating different files on Google Drive.
Domain=com.google.GTLRErrorObjectDomain Code=403 "Insufficient Permission"
UserInfo={GTLRStructuredError=GTLRErrorObject 0x170450d10: {message:"Insufficient
Permission" errors:[1] code:403}, NSLocalizedDescription=InsufficientPermission
I am defining scopes with Google SignIn as:
[[GIDSignIn sharedInstance].scopes
arrayByAddingObject:#[kGTLRAuthScopeDriveFile,kGTLRAuthScopeDrive,
kGTLRAuthScopeDriveMetadata]];
Google Drive API is enable on Google Console but still I do not know why I am getting this error. I also tried to turn on "OAuth 2.0" for Google Drive service on console but google is not allowing me and automatically turn it off. Any help will be appreciated.

Answer 1

Google changed it's authentication policy for it's API's. Now native web views for OAuth flow is not allowed by them but users are pushed to use OS browsers. They also introduced Google SignIn button SDK that is used for user login, if user wants to use Google Service. Google SignIn button(GIDSign) handle some authentication flow for users. Users can also use updated "GMTAppAuth" and "AppAuth" for implementation of GTMFetcherAuthorizationProtocol for authorizing request for AppAuth. I was using Google Drive API in one of my application and using "GTMOAuth2ViewControllerTouch" for Google Sign In and authentication but after update, it stopped working. In my above mentioned question, I am using Google SignIn for authentication. In old code, you can use Authentication NSString* constants "GTLRAuthScopeDriveFile" to define scope but now they changed the way and that's why I am getting error.
Old way of defining scope:
- (GTMOAuth2ViewControllerTouch *)createAuthController {
NSArray *scopes = [NSArray arrayWithObjects:kGTLRAuthScopeDriveFile, kGTLRAuthScopeDrive,nil];
authController = [[GTMOAuth2ViewControllerTouch alloc]
initWithScope:[scopes componentsJoinedByString:#" "]
clientID:kClientID
clientSecret:nil
keychainItemName:kGTMAppAuthKeychainItemName
delegate:self
finishedSelector:#selector(viewController:finishedWithAuth:error:)];
return authController;
}
New corrected way:
NSString *driveFile = #"https://www.googleapis.com/auth/drive.file";
[GIDSignIn sharedInstance].scopes = [currentScopes arrayByAddingObject:driveFile];