Get access token for gmail api via objective-c - ios

Question

I used the code from this sample. To get the number of user's unread messages (that's what I need), I need to send this GET request
https://www.googleapis.com/gmail/v1/users/me/labels/UNREAD?key={MY_API_KEY}
like in this example. But I guess that the {ACCESS_TOKEN} should be here instead of {MY_API_KEY}. If so, could anybody tell me how to get the access token using AFNetworking or auth from the sample?

Answer 1

As discussed in Authorizing Your App with Gmail
Gmail uses the OAuth 2.0 protocol for authenticating a Google account and authorizing access to user data. You can also use Google+ Sign-in to provide a "sign-in with Google" authentication method for your app.
If using AFNetworking is still your preference as requested, you may use the guide on how to get the access token given in this GitHub post - AFOAuth2Manager.
Solution given in this SO post - How to get the number of unread threads in INBOX with Gmail API might also help.

Answer 2

To get the access token to make an authorize request to the Google API you should implement the following methods:
- (GTMOAuth2ViewControllerTouch *)createAuthController {
GTMOAuth2ViewControllerTouch *authController;
// If modifying these scopes, delete your previously saved credentials by
// resetting the iOS simulator or uninstall the app.
NSArray *scopes = [NSArray arrayWithObjects:kGTLAuthScopeGmailReadonly, nil];
authController = [[GTMOAuth2ViewControllerTouch alloc]
initWithScope:[scopes componentsJoinedByString:#" "]
clientID:kClientID
clientSecret:nil
keychainItemName:kKeychainItemName
delegate:self
finishedSelector:#selector(viewController:finishedWithAuth:error:)];
return authController;
}
- (void)viewController:(GTMOAuth2ViewControllerTouch *)viewController
finishedWithAuth:(GTMOAuth2Authentication *)authResult
error:(NSError *)error {
if (error != nil) {
...
}
else {
NSLog(#"Access token: %#", authResult.accessToken);
}
}
And your ViewDidAppear method should looks like this:
- (void)viewDidAppear:(BOOL)animated {
if (!self.service.authorizer.canAuthorize) {
// Not yet authorized, request authorization by pushing the login UI onto the UI stack.
[self presentViewController:[self createAuthController] animated:YES completion:nil];
}
That code output the target access token.