如何在App iOS中管理令牌刷新

Question

I have a web site where I have built a API Rest for IOS app. The app is composed from a Tab bar with two views the first view show the view of WELCOME or LIST OF EVENTS it depends on if user is logged or no, and the second view show the LOGINVIEW. I have built the method on server that check if the token is valid yet in the time so that if the user has already made the login in the app, when the token will expire, I would like that the app would has to do a refresh token (by call to the server tokenIsAlive the response NO and it would make autoLogin in background) using the credential saved in the NSUserdefault in the device. But I would like that the refresh token would has to be hidden (background) so that the app can show the views where require the authenticated user. I have used AFNetworking but how can I make to refresh token hidden? Which way would be advised to check if the token is not expire? Does it to do for each call (getEvent,getListEvents,updateEvent..ecc) to the server, or only into the method

(void)applicationDidBecomeActive:(UIApplication *)application 

?

Answer 1

The easiest approach is to set an NSTimer to call a method that does the refreshing after a set time interval (depending on the expiry time of the token). Also, set the timer's repeat property to TRUE. This way, the token remains fresh and does not expire unless the user logs out. When the user logs out,make sure you invalidate the timer and stop refreshing the token.