I have a service that allows user to enter the type of events they like, and whenever a new event that fits those criteria is available in my database, I want them to get a notification.
I have been looking around at the best way to handle it and I have found two possible solutions, but I'm not very clear with which one I should use and how.
First, a solution that looked great was the didReceiveRemoteNotification method and the usage of remote silent notifications to tell the app that new content was available. But my questions remains: how can I send this remote notification to the user if I don't know which criteria he has. I mean, how can I send this notification using PHP? I'm a bit lost here.
So I found another possible solution that does look a lot like a hack (iPhone - Backgrounding to poll for events), to be able to make your app execute a method every XX minutes while it is in background. This would be way more battery consuming and I'm not even sure it would be accepted by Apple, but at least it is clear as to how it works: the app downloads data from a link with the parameters that fit the special criteria, and if there is new data, it sends a notification.
How could I combine both these methods?
EDIT
I think the main issue on my side is that I don't understand how I could check a certain PHP file whenever new data is added into mysql and make sure that it fits the criteria of the user and then send the notification. That is the part that I don't understand in the backend PHP usage.
Your flow should be like this -
Mobile -> BackendServer(PHP) -> APNS server -> Notifications->Back on device.
User will submit her/his criteria to server then server will process on that and send request to APNS server.
The APNS server will send remote notification on her/his device based on criteria requested.
Related
So my app extracts JSON from a server that i don't control, and parses that JSON to populate a UITableView.
I want to update my UITableView to reflect the latest information available on the server in real time. So Whenever something changes on the server my UITableView also gets updated.
Now one solution that comes to mind is to Continuously send GET Requests lets say after one minute, parse the JSON and reload data on the table.
However there must be some other solution for this problem. I have tried searching but thus far no success.
Now i understand this questions is somewhat subjective by stackoverflow's standards but really i need help regarding this matter and i haven't got the slightest clue on where to start. So any help would be greatly appreciated.
Repeated GETs are generally frowned upon, because it demands client and server resources when nothing is happening, which can be most of the time.
Since you don't control the server, I'd recommend building a server that you do control that can perform the polling, and then send the push upon detecting a change. This has a couple advantages over polling from the client: It scales better since only one source of polling will exist in the world, and it conserves client energy as well as the pure push approach does.
Apple provides a push system (APNS) wherein your server sends a message to your iOS device (via Apple). The device will launch your app in the background and invoke:
- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo;
on your app delegate.
As the above answer states, its better to use APNS.
if however, you truly do not control the server, then as you describe theres nothing you can do except poll. Since you're writing for iOS, you're well advised to consider a few things:
Wifi constraints: Are you fetching a tiny payload such that it doesn't matter whether you are on wifi? otherwise you ought to configure reachability to not be a drag on the users cellular service.
Backgrounding Sessions & background Execution: Consider using an NSBackgroundUrlSession to request this data. Backgrounding sessions are a bit more efficient to the OS in that they allow the OS to perform the request opportunistically. Consider The Background Execution entitlement if You need to customize the NSURLSessionTasks for the background session.
Scalability: can your backend handle continuous requests from your volume of users?
better solutions might utilize APNS, or Socket / WebSockets / Socket.io / firebase / etc.
Normal Silent Notification is best solution for this
When you adding any new item on server that time you can send push notification (Silent push notification) to devices to notify status that you added something on server side.
When device receives such push notifications then you have to call API and reload your table view. So you don't have to reload tableview every 10 sec.
It "will not show notification alert in notification bar, but it will only notify your app that there is some new data available, when you want to push new content.
Displayed in Notification center : No
Awake app to perform background task : Yes
just add below paylod from server side in push notification
{
"content-available" : 1
}
{
"content-available" : 1
}
I am quite new into programming and I cant find efficient solution for my problem. Could someone point me in the right direction please?
I have an app which is heavily relying on server data. Data on server is unique for each user and may change every minute as well as only every few hours. Currently I am updating local data when app becomes active but I also need a way of notifying app to trigger updates when app stays in active state and data has changed on server. I thought about few solutions:
1) NSTimer set to one minute and triggering url request to check if there is new data on server. Server after comparing lastModified value would return new data if available.
I don't really like that solution as I don't want to overload my server with number of requests, especially that data in the database may change only every few hours or even longer.
2) APNS - sending notifications from server every time data will change and than update local data with server database when notification received.
It seems like a good solution but only if it would be possible to restrict remote notifications to be received when app is in active state. As far I know it is not possible and as I mentioned before data may change even every minute so I don't want to spam users with number of notifications when app is not running.
3) TCP Sockets using NSStream/CFStream?
This is something I never did before, so I am not even sure if I am going in the right direction researching about this one.
This is a hard topic in general, but more technologies are coming out to help with it. Couple thoughts on each of your solutions:
The NSTimer solution is effectively polling, which is the worst option I feel. You'd be hitting your server pretty hard for each user.
This would be a better solution. APNS now supports silent notifications, so you can send push notifications to a user without worrying about notifying them. You can send a silent notification by including the content-available key in the payload and not including the alert key. More info here: http://hayageek.com/ios-silent-push-notifications/. It is rate limited, though. You may go minutes to hours without getting a delivery, so if that's important you'd be best to go to option 3.
This is your best solution. It would require a persistent connection with your server. AFNetworking 2.0 supports this kind of connection based on Rocket. Here's Rocket's documentation: http://rocket.github.io. Take a look at server-sent events.
Hope that helps!
i'm writing an app that manage a sqlite database, and i have write a web server, i want the user register in my web server with username and password, i already know how make a request from ios app to server and receive the response, but i want enable also the synchronization of the sqlite database to other device, i now that with core data i can use iCloud synchronization, but for now i prefer use sqlite, and find a way to synchronize it, for example i want create this:
make a change in the sqlite in the iPhone app;
the app send this change to the server for that user;
then the server have to send this update to other device connected at that user;
and now i can't go over, how the server can send this change to the other device? the device has to be always listen to the server? or there is a way to send this update directly to some device and handle it? like an apple push notification?
EDIT: if it's possible use an apple push notification to do this, i doesn't want alert with text sound and badge the user, but send a "silent notification" it's possible?
As a high-level there are a few different ways to approach this, all of which have pros and cons. Two name two examples you can do a polling method, active push or a hybrid approach.
Polling: at some pre-determined interval the app tries to "phone home" and send the delta db changes up to the server. Here you know that your server will be expecting X number of responses in any given interval so you can appropriately gauge your load.
Active Push: The user decides when they want those changes to be transmitted to the server by hitting a "Sync" button. This allows the user to only push data back up to the server when they know there's a change but an over zealous user may make a change, upload, make a change, upload, etc instead of queueing up a bunch of changes and sending them all at once. This may create frequently unneeded server calls.
Hybrid: You setup a polling schedule within the app AND give the user the ability to Sync at-will in the event there is a critical change that needs to be made ASAP.
Regarding the listener side of the equation you face a similar challenge conceptually. If the original user makes 20 changes and presses Sync 20 times do you bombard the second user's device 20 times as well or do you queue those changes up and send them down every 5 minutes (as an example)? Unless you have both devices paired to each other or are connected to the same network AND visible to each other via your app you're going to need to leverage that back-end server. Push notifications can be very useful in this manner but there is extra development and setup overhead to take into account to properly implement them.
To boil this all down I would recommend laying out what YOU want your syncing model to look like before you start marching down a path.
im stuck in a situation
SITUATION : I have a situation wherein i answer some questions and get points according to the answered questions. if my points become say 10 i win some gift using a QRCode. (there is a qr code that is generated to the user, and when the qrcode is scanned from someother device which has a scanner app or any other scanner, it gives a link to that online store. This link can be opened from any browser.) The gift is accessed from some online store by scanning the QRCode which gives a link to that online store with some unique id and when the gift is accessed/taken the server is notified that the gift is accessed/taken from that online gift store and the QRCode status is updated to invalid on the server database. Now once the server gets the notification that the gift is being accessed/taken, the server should immediately notify my iphone app that the gift is received so that i can immediately show another congratulations image or something.
POSSIBLE SOLUTION : i thought of one possible solution wherein i check upon the qrcode access status change on the server every say 60 secs and display the image accordingly. I dont know how efficient/correct this way would be though.
ISSUE : but before i refuge to the above solution, i want to know, can this notification happen from the server without my app trying to call or fetch the update from the server? I mean, my app comes into the picture only after the server sends a notification in the form of a msg or some xml or something..
Any help would be deeply appreciated.
You can open a connection to your server using CFReadStream, add the stream to your runloop and set up a callback function. Whenever the server writes data to the open connection, your callback will fire and you can then read from the stream to get the data the server sent
More info here: https://developer.apple.com/library/mac/#documentation/Networking/Conceptual/CFNetwork/CFStreamTasks/CFStreamTasks.html
You could try to check Push Notifications. But it's impossible to determine on server side if notification was received on client side or not (if you won't implement it by yourself, but you'll probably wont cover all the possible situations, like when your app is not launched and notification came).
you can try to use XMPP protocol, which is most commonly used for chats/mails, where the changes in the server is notified to the clients.
Apple Push Notification Service is meant to solve these types of situations.
Hope it helps:
Apple Docs: http://developer.apple.com/library/ios/#documentation/NetworkingInternet/Conceptual/RemoteNotificationsPG/ApplePushService/ApplePushService.html#//apple_ref/doc/uid/TP40008194-CH100-SW9
There is a nice tutorial: http://www.raywenderlich.com/3443/apple-push-notification-services-tutorial-part-12
Video tutorial: http://www.youtube.com/watch?v=cKV5csbueHA&feature=relmfu
Within my iPhone application I periodically make calls to a webservice, providing the endpoint with a list of numeric IDs. The webservice then returns information relating to the IDs it receives.
This is all well and good. However, I would like to be able to provide functionality whereby the user will receive a local/push notification when these changes occur, regardless of whether the application is open or not.
I'm just looking for guidance on my options in this scenario. As I see it, there are two main approaches: calculate any data changes on my webserver and send a push notification to all devices, or query the webservice from the device itself.
The second option seems ideal, as not all devices will need each push notification, but I'm unsure as to whether this is possible with the current state of iOS' multitasking APIs. Any advice would be appreciated.
Bad news: it's not possible. Apps can only run in the background for a short period of time after the user has exited unless it fits into a small number of categories (GPS, VoIP, etc).
Web services, unfortunately, do not count. So this would have to be performed on the server side and with push notifications.