In the Apple documentation you can find the following sentence :
An application should register every time it launches and give its provider the current token. It calls registerForRemoteNotificationTypes: to kick off the registration process.
So when I implemented the push notification in my app I had to register the device, and I did what they said in that documentation: registering every time a user launch my app.
The token that I receive from the APNS is always the same for a given user.
My question is: why do I need to register everytime if the APNS gives me always the same token?
I read somewhere than a token can change if a user swipe his iPhone or the app. Is it the only case?
Thank you !
The token that I receive from the APNS is always the same for a given user.
Except it isn't, basically because there's nothing you can hang onto as being "a user" in the iPhone setup. The device token is always the same for each app for each device. So different apps on the same device get different tokens. The same app on two different devices gets two different tokens.
The crucial thing to note, and this is mentioned in the APNS guide, is that a user may back up their apps, settings, everything. Then they can drop their phone down the toilet. When they get their replacement phone, they can take their backup and restore it onto their new phone. Bingo - same app, same user, different device, and different token.
As far as your app is concerned, nothing has changed since the last time it ran - it doesn't know that it's actually running on a different device now. The only way it knows is because it asks for the 'current' device token, and hey presto it's a different token to last time.
You can choose to cache the token and check it against the token you just received (e.g. save it in your NSUserDefaults) - that way you don't have to communicate it back to the server unless it has changed since the last run, but you absolutely do have to check, otherwise your users will come complaining that they don't get push notifications any more since they replaced their phone.
Related
In my application , i works with web-services and when user log in into my app my app is sending a request with status 1 means loged in and when on log out button click sending a request with status 0.
Now problem is , when user removes app from devices , status in my server is remain 1(log in) , hence other user can see him available while his app is not in device. so is there any way by which i can send request when my app removes from device (i don't think it is possible) or is there any other way that i can do in my backend side ?
Thanks in advance.
It is not possible to call a web service when the user deleting the app from an ios device. There are three methods to came to know that whether your application is there in user's ios device. But there are few limitations also.
Activate Push notification: By doing this, device will get registered with Apple's push notification service. When user delete the app from device, the registration will be revoked from APNS server and through the APNS feedback service, you can get to know whether the application is existing. (Limitation: If the user did not agree with receiving push notifications, then the app will not be registered with APNS and you never came to know that whether application is existing or not)
Activate Location Based service: If your application enables location based service, then your application will get periodic location updates in a location delegate method. In this delegate, you can call a webservice and keep update the status of user even the application is in background. (Limitation: If user disables the location update, then your server will not get info about user status)
Periodically Call a Webservice From you app: This is possible only if your app is active. (Limitation: When you application pushed in to background, your application will be in suspended mode, so it will not possible to call webservice)
Sorry Unfortunately Apple not provide any method that user Uninstall app from user's device, There is no such method.
When user delete any application device does give the alert "Do you want to delete this application" with option "Delete" and "Cancel". You don't have to write any specific code for this.
I just assume that There is one method in which you can find out when user is about to delete your app. That is you need to implement push notification Apple server will inform you when you try to push to an uninstalled instance. Other than that there's no way to detect it but i am not sure its helpful or not.
You can't do this from within the app. You would want to do something like have a periodic task which runs on the backend, checking the last activity date of logged in users and setting them to 'not available' after some configured period of inactivity. This will probably require some changes to the backend to record last activity date and a change to the app so that while it's open it sends a periodic 'heartbeat' to the backend. You probably want to make the timeout quite big (say 15 minutes, big enough to not have a large impact on performance).
I’m looking at the designing and developing a service for Push notifications, and am trying to understand the order of processing in the Apple App when it comes to Registering for Push Notifications and storage of the Token.
What I’m developing currently is a service that allows subscription to individual changes that happen to particular processing on our server.
When they happen, the phone user may receive a message of type “A”, “B”, or “C”.
The phone user has to “subscribe” to each of these types individually if they want them. Otherwise they can ignore it and not subscribe.
So User Fred, on Phone #4, starts our App, logs in, and then has the ability to turn on or off subscriptions to events that are sent as Push Notifications.
So I need to tie details from Fred’s login, to Phone #4’s device Token, with particular subscriptions.
So my particularly important questions are.
When the Phone connects to the APNS server to get its device token, is this automatic on app start? Or can this be initiated at a later step? Ie, after going through a loging screen on our app.
Can we (are we allowed to) store the device token on the phone in the App's data store?. Or, should the App be connecting to the APNS server every time the app is run?
How does the App know if it as already called the APNS server and retrieved a token, or as above, should it call the APNS server time the app is run?
Can we (are we allowed to) store the token in the App’s memory as it runs, so we can properly subscribe and unsubscribe for particular messages?
We need also to be able to list all the subscriptions that a particular user may have across all their devices so the user can remove old devices (if they change phones). Or can we rely upon data back from calls to the APNS – when we attempt to push a notification - to inform us that a device token is no longer valid?
Or is there some better way of tying this all together?
When the Phone connects to the APNS server to get its device token, is
this automatic on app start? Or can this be initiated at a later step?
Ie, after logging into our app.
After the app has started, the app gets the token by calling registerForRemoteNotificationTypes. This will prompt the user for permission, and call a callback with the device token if permission is granted.
Can we (are we allowed to) store the device token on the phone in the
Apps data store?. Or, should the App be connecting to the APNS server
every time the app is run?
You'll need to build an APN provider, which is a web server that calls apple to send the pushes. The thing to do with the token is post it to your server that uses the APN provider. The app doesn't connect to APNS, your provider does, and it does it when it has pushes to send.
Can we (are we allowed to) store the token in the App’s memory as it
runs, so we can properly subscribe and unsubscribe for particular
messages?
You can keep the token on the client, but you don't really need to. It's your web service that calls APN, so it needs to be kept aware of your users' subscription prefs.
We need also to be able to list all the subscriptions that a
particular user may have across all their devices so the user can
remove old devices (if they change phones). Or can we rely upon data
back from calls to the APNS – when we attempt to push a notification -
to inform us that a device token is no longer valid?
APN also provides a feedback service that you call in batch which returns the device tokens that are no longer valid. Not only can you use this service, but you must. Apple will get mad at apps that repeatedly send to no longer valid devices.
Or is there some better way of tying this all together?
Yes! Parse.com provides a nice wrapper on the client code, does the provider and feedback service, abstracts the idea of single devices to the idea of a "channel" which sounds like just what you need for multiple notification types A, B, C, provides a super-easy step by step setup, and loads of other useful cloud services for iOS. (I'm not affiliated, but a big fan).
In my app, for first time push notification registration, I call didRegisterForRemoteNotificationsWithDeviceToken and save the device token in persistence as well as update my server list for device token. Now afterwards if somebody turns the push notification settings off from iPhone Settings how can I determine it from my app so that I can remove the device token from server as well. I know APNS provides a feedback list, but other than that is there a way to determine it in App programmatically? Thanks for any help!
I believe you do not want to manage tokens this way.
Your app should always be asking Apple for an APNs token. You should always then send that token to your own server, likely associating the token with your user (if you have one). You do this because the token could change, so you want to make sure you always have up-to-date tokens.
The Feedback service will tell you (actually, you poll it at some interval of your choosing) which tokens have become invalid. At this point, you remove the tokens from your server-side database. To be clear, you need a server-side process that polls Apple's feedback service and then updates your server-side database.
You will not receive feedback about invalid tokens until you try to send a notification using the token. The notification will (I believe) be accepted by Apple when you send it, but when Apple discovers it's for an invalid token, the message is dropped, and the token is added to your feedback.
Now, if the user of your app accepts push notifications when your app first asks about it, but later turns off notifications via the Settings app for your app, you will not get any feedback about it. What happens, near as I can tell, is that any notification you send to that device will be sent to the device, but the OS drops it, honoring the user's ultimate choice in the Settings app for your app and notifications.
Finally, there is an API you can call in your app to get a bitmask of which kinds of notifications are enabled for your app on the device. Here's a method I wrote for this purpose; adjust as needed:
+(BOOL)acceptsPushNotifications
{
UIRemoteNotificationType mask = [[UIApplication sharedApplication] enabledRemoteNotificationTypes];
return (mask & UIRemoteNotificationTypeAlert) == UIRemoteNotificationTypeAlert;
}
But I would not recommend using this to decide if you app should tell your server to delete the token from your database. That's not how the whole APNs system is intended to work... I believe.
I have to developp an app that uses Push Notification in a particular way, and I had a pretty tricky question : can the device token be stored locally in the app sandbox?
Here's the why : this app should implement a notification system that allows the user to subscribe for some particular events only, from the iphone.
So to do so, I need to send to my database the Device Token of the iPhone at any time when the app is running, and from what I get, the device token is only avaliable when the
- (void)application:(UIApplication *)application didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)deviceToken
is called right?
Or is there any way to retrieve this information later?
Thanks.
The push notification programming guide however recommends you not to store the token locally:
"An application should register every time it launches and give its provider the current token. It calls registerForRemoteNotificationTypes: to kick off the registration process."
…
"By requesting the device token and passing it to the provider every time your application launches, you help to ensure that the provider has the current token for the device. If a user restores a backup to a device other than the one that the backup was created for (for example, the user migrates data to a new device), he or she must launch the application at least once for it to receive notifications again. If the user restores backup data to a new device or reinstalls the operating system, the device token changes. Moreover, never cache a device token and give that to your provider; always get the token from the system whenever you need it. If your application has previously registered, calling registerForRemoteNotificationTypes: results in iOS passing the device token to the delegate immediately without incurring additional overhead."
You should store it somewhere on the phone. NSUserDefaults is a decent place to do it since it's not a big piece of data and you can retrieve it easily afterwards. I would also recommend saving it on your server, and only updating it if the token changes.
How to test feedback.sandbox.push.apple.com? Everything goes right, but I receive empty list.
How to make it consider the device token as inactive?
I installed the application to iPhone using Xcode, received some push notifications, then removed it from iPhone and send some more notifications. But even on the next day feedback.sandbox.push.apple.com returns just empty set.
Issues with Using the Feedback Service
If you remove your app from your device and then send a push notification to it, you would expect to have the device token rejected, and the invalidated device token should appear on the feedback service. However, if this was the last push-enabled app on the device, it will not show up in the feedback service. This is because deleting the last app tears down the persistent connection to the push service before the notice of the deletion can be sent.
You can work around this by leaving at least one push-enabled app on the device in order to keep the persistent connection up. Just install any free push-enabled app from the App Store and you should then be able to delete your app and see it appear in the feedback service.
source:
http://developer.apple.com/library/ios/technotes/tn2010/tn2265.html#TNTAG34
I far as I found, Apple push notification feedback service doesn't work properly on sandbox mode. You should try it on ad-hoc or production mode.