How to send a silent Push Notification payload

Question

I just want to know how I can determine what action to do on a silent push:

This is the aps that I sent to the client:

"aps": {
    "content-available": 1
}

My problem now is when I add type: "Order_Update" to determine that the silent push is for the Order Update to display an alert notification.

Codger

Answer 1

There are a few options for it! Let's take a small ride to understand all the different payloads and their usage.

---

Simple Payload

Displayed in Notification Center : Yes

Wakes app to perform background task : No

{
    "aps" : {
        "alert" : "You received simple notification!",
        "badge" : 1,
        "sound" : "default"
    }
}

---

Payload With Custom Notification Sound

Displayed in Notification Center : Yes

Wakes app to perform background task : No

Step 1 : Add custom notification sound file (.wav or .aiff extensions only. e.g. notification.wav) in your app bundle.

Step 2 : Configure your payload as shown below to play your custom sound

{
    "aps" : {
        "alert" : "It's a custom notification sound!",
        "badge" : 1,
        "sound" : "notification.wav"
    }
}

---

Notification With Custom Payload

Displayed in Notification Center : Yes

Wakes app to perform background task : No

{
    "aps" : {
        "alert" : "It's a notification with custom payload!",
        "badge" : 1,
        "content-available" : 0         
    },
    "data" :{
        "title" : "Game Request",
        "body" : "Bob wants to play poker",
        "action-loc-key" : "PLAY"
    },

}

Here the data dictionary holds custom information whatever you want. It will also display as normal notification with the alert message "It's a notification with custom payload!".

---

Normal Silent Notification

It will not a show an alert as a notification bar; it will only notify your app that there is some new data available, prompting the app to fetch new content.

Displayed in Notification center : No

Awake app to perform background task : Yes

{
    "content-available" : 1
}

---

Silent Notification With Custom Payload

Here comes the magic to show a notification alert as well awake your app in background for a task! (Note: only if it's running in background and has not been killed explicitly by the user.) Just add the extra parameter "content-available" : 1 in your payload.

Displayed in Notification Center : Yes

Wakes app to perform background task : Yes

{
    "aps" : {
        "alert" : "Notification with custom payload!",
        "badge" : 1,
        "content-available" : 1
    },
     "data" :{
        "title" : "Game Request",
        "body" : "Bob wants to play poker",
        "action-loc-key" : "PLAY"
     }
}

---

Use any of these payloads according to your app requirements. For background app refresh refer to Apple's documentation. I hope this gives you all the necessary information. Happy coding :)

Chuvash

Great answer but I think you miss data parameter in Notification with custom payload section. – Cheddar

Thanks @LiborZapletal for noting it, i have updated answer. – Chuvash

According the Apple documentation the "content-available' must be inside the "aps". developer.apple.com/library/content/documentation/… Why you use it outside of the "aps"? – Natashianatassia

@Natashianatassia yes you are right, it should be under "aps", I have updated answer. Thanks for pointing out. – Chuvash

For the Silent notification, can I have client-side logic to decide whether to display the notification or not? – Sequacious

No you cant have client side logic as its decided by System based on payload , but based on payload "content-available" you can take some action – Chuvash

I can't see any difference between 3rd example (Notification with custom payload) and 5th(Silent Notification with custom payload) example push dictionary. Why it causes different background execution behaviour, NO for the 3rd and YES for the 5th? They are both bring app to Background State and execute code, if some project settings enabled. – Genetics

@AlexanderLarionov I believe that the 3rd example should say "0" for content available, and "1" for the 5th example.That's the flag that adds the "silent" feature – Unbreathed

@Unbreathed you are right, modified answer as suggested – Chuvash

I try to use the example "Silent notification with custom payload" but if the application is in foreground the system notification appear, i think if the alert is present it isn't silent notification. it is true? – Bumgardner

@DipenPanchasara thanks for the insight. When you say wakes app to perform background task, does the app trigger "applicationDidFinishLauchingWithOptions:" upon receiving the silent push? – Whilom

@rach No, it just invokes background task block which you have implemented for remote push-notification. It awakes app for particular task and suspends again, you can't perform long running task there. Hope it would be helpful :) – Chuvash

@DipenPanchasara @rach It does call applicationDidFinishLauchingWithOptions. In our case the app is killed from the apps tray. But when a push notification with content-available 1 payload is received. applicationDidFinishLauchingWithOptions is invoked. Another reference: https://mcmap.net/q/408993/-didfinishlaunchingwithoptions-background-resume-or-full-launch – Trilinear

is sound parameter with 'defalut' is required to play ios custom sound ? – Merovingian

Answer 2

As i understand, you want extra data inside payload, so you can identify what push notification type is,or what action need to be handled.

For that edit your payload as:

 $body = array(
    'content-available' => 1,
    'sound' => ''
    );  

$payload = array();
$payload['aps'] = $body;
$payload['action'] = 'order_update';

Then in your iOS Code:

- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo
{


    NSString *action = userInfo["action"];


    if([userInfo[@"aps"][@"content-available"] intValue]== 1 && [action isEqualToString:@"order_update") //order update notification
    {
        //handle Your Action here
        return;
    }


}

Hope this solves your problem!

Termless

Answer 3

Please also check apns-push-type (Required for watchOS 6 and later; recommended for macOS, iOS, tvOS, and iPadOS) The value of this header must accurately reflect the contents of your notification’s payload. If there is a mismatch, or if the header is missing on required systems, APNs may return an error, delay the delivery of the notification, or drop it altogether. https://developer.apple.com/documentation/usernotifications/setting_up_a_remote_notification_server/sending_notification_requests_to_apns

Ulm