How to update the token I received from google oauth 2.0 in iOS

Question

I am making an iOS application that uses a google user account to retrieve data from my YouTube account and show it .... the first step is using gtm2 to authenticate the user and get the access token and update token the problem is that the access token expires after 60 minutes, and I need to log in and turn on the application again ... I found that you can use the update token to get a new access token using this from the documentation: -> My question is how with elat POST request for an access token in objective-c is the data that I need to use:

POST /o/oauth2/token HTTP/1.1 Host: accounts.google.com Content-Type: application/x-www-form-urlencoded client_id=21302922996.apps.googleusercontent.com& client_secret=XTHhXh1SlUNgvyWGwDk1EjXB& refresh_token=1/6BMfW9j53gdGImsixUH6kU5RsR4zwI9lUVX-tqf8JXQ& grant_type=refresh_token 

this is the code i use:

 NSString *post =[[NSString alloc] initWithFormat:@"client_secret=%@&grant_type=refresh_token&refresh_token=%@&client_id%@",kGoogleClientSecretKey,kRefreshToken,kGoogleClientIDKey]; NSLog(@"%@",post); NSURL *url=[NSURL URLWithString:@"https://accounts.google.com/o/oauth2/token"]; NSData *postData = [post dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES]; NSString *postLength = [NSString stringWithFormat:@"%d", [postData length]]; NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init] ; [request setURL:url]; [request setHTTPMethod:@"POST"]; [request setValue:postLength forHTTPHeaderField:@"Content-Length"]; [request setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"]; [request setHTTPBody:postData]; NSError *error; NSURLResponse *response; NSData *urlData=[NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&error]; NSString *data=[[NSString alloc]initWithData:urlData encoding:NSUTF8StringEncoding]; NSLog(@"%@",data); 

the error I get is: {"error": "invalid_request"}

Answer 1

Your format string is missing = .

Edit

 NSString *post =[[NSString alloc] initWithFormat:@"client_secret=%@&grant_type=refresh_token&refresh_token=%@&client_id%@",kGoogleClientSecretKey,kRefreshToken,kGoogleClientIDKey]; 

to

 NSString *post =[[NSString alloc] initWithFormat:@"client_secret=%@&grant_type=refresh_token&refresh_token=%@&client_id=%@",kGoogleClientSecretKey,kRefreshToken,kGoogleClientIDKey];