13 KiB
13 KiB
Push Notifications
APNs setup, registration, rich notifications, and silent push.
Basic Setup
Request Permission
import UserNotifications
class PushService: NSObject {
static let shared = PushService()
func requestPermission() async -> Bool {
let center = UNUserNotificationCenter.current()
center.delegate = self
do {
let granted = try await center.requestAuthorization(options: [.alert, .sound, .badge])
if granted {
await registerForRemoteNotifications()
}
return granted
} catch {
print("Permission request failed: \(error)")
return false
}
}
@MainActor
private func registerForRemoteNotifications() {
UIApplication.shared.registerForRemoteNotifications()
}
func checkPermissionStatus() async -> UNAuthorizationStatus {
let settings = await UNUserNotificationCenter.current().notificationSettings()
return settings.authorizationStatus
}
}
extension PushService: UNUserNotificationCenterDelegate {
// Handle notification when app is in foreground
func userNotificationCenter(
_ center: UNUserNotificationCenter,
willPresent notification: UNNotification
) async -> UNNotificationPresentationOptions {
return [.banner, .sound, .badge]
}
// Handle notification tap
func userNotificationCenter(
_ center: UNUserNotificationCenter,
didReceive response: UNNotificationResponse
) async {
let userInfo = response.notification.request.content.userInfo
// Handle action
switch response.actionIdentifier {
case UNNotificationDefaultActionIdentifier:
// User tapped notification
handleNotificationTap(userInfo)
case "REPLY_ACTION":
if let textResponse = response as? UNTextInputNotificationResponse {
handleReply(textResponse.userText, userInfo: userInfo)
}
default:
break
}
}
private func handleNotificationTap(_ userInfo: [AnyHashable: Any]) {
// Navigate to relevant screen
if let itemID = userInfo["item_id"] as? String {
// appState.navigateToItem(id: itemID)
}
}
private func handleReply(_ text: String, userInfo: [AnyHashable: Any]) {
// Send reply
}
}
Handle Device Token
In your App or AppDelegate:
// Using UIApplicationDelegateAdaptor
@main
struct MyApp: App {
@UIApplicationDelegateAdaptor(AppDelegate.self) var delegate
var body: some Scene {
WindowGroup {
ContentView()
}
}
}
class AppDelegate: NSObject, UIApplicationDelegate {
func application(
_ application: UIApplication,
didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data
) {
let token = deviceToken.map { String(format: "%02.2hhx", $0) }.joined()
print("Device Token: \(token)")
// Send to your server
Task {
try? await sendTokenToServer(token)
}
}
func application(
_ application: UIApplication,
didFailToRegisterForRemoteNotificationsWithError error: Error
) {
print("Failed to register: \(error)")
}
private func sendTokenToServer(_ token: String) async throws {
// POST to your server
}
}
Rich Notifications
Notification Content Extension
- File > New > Target > Notification Content Extension
- Configure in
Info.plist:
<key>NSExtension</key>
<dict>
<key>NSExtensionAttributes</key>
<dict>
<key>UNNotificationExtensionCategory</key>
<string>MEDIA_CATEGORY</string>
<key>UNNotificationExtensionInitialContentSizeRatio</key>
<real>0.5</real>
</dict>
<key>NSExtensionMainStoryboard</key>
<string>MainInterface</string>
<key>NSExtensionPointIdentifier</key>
<string>com.apple.usernotifications.content-extension</string>
</dict>
- Implement
NotificationViewController:
import UIKit
import UserNotifications
import UserNotificationsUI
class NotificationViewController: UIViewController, UNNotificationContentExtension {
@IBOutlet weak var imageView: UIImageView!
@IBOutlet weak var titleLabel: UILabel!
func didReceive(_ notification: UNNotification) {
let content = notification.request.content
titleLabel.text = content.title
// Load attachment
if let attachment = content.attachments.first,
attachment.url.startAccessingSecurityScopedResource() {
defer { attachment.url.stopAccessingSecurityScopedResource() }
if let data = try? Data(contentsOf: attachment.url),
let image = UIImage(data: data) {
imageView.image = image
}
}
}
}
Notification Service Extension
Modify notification content before display:
- File > New > Target > Notification Service Extension
- Implement:
import UserNotifications
class NotificationService: UNNotificationServiceExtension {
var contentHandler: ((UNNotificationContent) -> Void)?
var bestAttemptContent: UNMutableNotificationContent?
override func didReceive(
_ request: UNNotificationRequest,
withContentHandler contentHandler: @escaping (UNNotificationContent) -> Void
) {
self.contentHandler = contentHandler
bestAttemptContent = (request.content.mutableCopy() as? UNMutableNotificationContent)
guard let bestAttemptContent = bestAttemptContent else {
contentHandler(request.content)
return
}
// Download and attach media
if let imageURLString = bestAttemptContent.userInfo["image_url"] as? String,
let imageURL = URL(string: imageURLString) {
downloadImage(from: imageURL) { attachment in
if let attachment = attachment {
bestAttemptContent.attachments = [attachment]
}
contentHandler(bestAttemptContent)
}
} else {
contentHandler(bestAttemptContent)
}
}
override func serviceExtensionTimeWillExpire() {
// Called just before extension is terminated
if let contentHandler = contentHandler,
let bestAttemptContent = bestAttemptContent {
contentHandler(bestAttemptContent)
}
}
private func downloadImage(from url: URL, completion: @escaping (UNNotificationAttachment?) -> Void) {
let task = URLSession.shared.downloadTask(with: url) { location, _, error in
guard let location = location, error == nil else {
completion(nil)
return
}
let tempDirectory = FileManager.default.temporaryDirectory
let tempFile = tempDirectory.appendingPathComponent(UUID().uuidString + ".jpg")
do {
try FileManager.default.moveItem(at: location, to: tempFile)
let attachment = try UNNotificationAttachment(identifier: "image", url: tempFile)
completion(attachment)
} catch {
completion(nil)
}
}
task.resume()
}
}
Actions and Categories
Define Actions
func registerNotificationCategories() {
// Actions
let replyAction = UNTextInputNotificationAction(
identifier: "REPLY_ACTION",
title: "Reply",
options: [],
textInputButtonTitle: "Send",
textInputPlaceholder: "Type your reply..."
)
let markReadAction = UNNotificationAction(
identifier: "MARK_READ_ACTION",
title: "Mark as Read",
options: []
)
let deleteAction = UNNotificationAction(
identifier: "DELETE_ACTION",
title: "Delete",
options: [.destructive]
)
// Category
let messageCategory = UNNotificationCategory(
identifier: "MESSAGE_CATEGORY",
actions: [replyAction, markReadAction, deleteAction],
intentIdentifiers: [],
options: []
)
// Register
UNUserNotificationCenter.current().setNotificationCategories([messageCategory])
}
Send with Category
{
"aps": {
"alert": {
"title": "New Message",
"body": "You have a new message from John"
},
"category": "MESSAGE_CATEGORY",
"mutable-content": 1
},
"image_url": "https://example.com/image.jpg"
}
Silent Push
For background data updates:
Configuration
Add to entitlements:
<key>UIBackgroundModes</key>
<array>
<string>remote-notification</string>
</array>
Handle Silent Push
class AppDelegate: NSObject, UIApplicationDelegate {
func application(
_ application: UIApplication,
didReceiveRemoteNotification userInfo: [AnyHashable: Any]
) async -> UIBackgroundFetchResult {
// Process in background
do {
try await syncData()
return .newData
} catch {
return .failed
}
}
private func syncData() async throws {
// Fetch new data
}
}
Send Silent Push
{
"aps": {
"content-available": 1
},
"data": {
"type": "sync",
"timestamp": "2025-01-01T00:00:00Z"
}
}
Local Notifications
Schedule notifications without server:
class LocalNotificationService {
func scheduleReminder(title: String, body: String, at date: Date, id: String) async throws {
let content = UNMutableNotificationContent()
content.title = title
content.body = body
content.sound = .default
let components = Calendar.current.dateComponents([.year, .month, .day, .hour, .minute], from: date)
let trigger = UNCalendarNotificationTrigger(dateMatching: components, repeats: false)
let request = UNNotificationRequest(identifier: id, content: content, trigger: trigger)
try await UNUserNotificationCenter.current().add(request)
}
func scheduleRepeating(title: String, body: String, hour: Int, minute: Int, id: String) async throws {
let content = UNMutableNotificationContent()
content.title = title
content.body = body
content.sound = .default
var components = DateComponents()
components.hour = hour
components.minute = minute
let trigger = UNCalendarNotificationTrigger(dateMatching: components, repeats: true)
let request = UNNotificationRequest(identifier: id, content: content, trigger: trigger)
try await UNUserNotificationCenter.current().add(request)
}
func cancel(_ id: String) {
UNUserNotificationCenter.current().removePendingNotificationRequests(withIdentifiers: [id])
}
func cancelAll() {
UNUserNotificationCenter.current().removeAllPendingNotificationRequests()
}
}
Badge Management
extension PushService {
func updateBadge(count: Int) async {
do {
try await UNUserNotificationCenter.current().setBadgeCount(count)
} catch {
print("Failed to set badge: \(error)")
}
}
func clearBadge() async {
await updateBadge(count: 0)
}
}
APNs Server Setup
Payload Format
{
"aps": {
"alert": {
"title": "Title",
"subtitle": "Subtitle",
"body": "Body text"
},
"badge": 1,
"sound": "default",
"thread-id": "group-id",
"category": "CATEGORY_ID"
},
"custom_key": "custom_value"
}
Sending with JWT
curl -v \
--header "authorization: bearer $JWT" \
--header "apns-topic: com.yourcompany.app" \
--header "apns-push-type: alert" \
--http2 \
--data '{"aps":{"alert":"Hello"}}' \
https://api.push.apple.com/3/device/$DEVICE_TOKEN
Best Practices
Request Permission at Right Time
// Don't request on launch
// Instead, request after value is demonstrated
func onFirstMessageReceived() {
Task {
let granted = await PushService.shared.requestPermission()
if !granted {
showPermissionBenefitsSheet()
}
}
}
Handle Permission Denied
func showNotificationSettings() {
if let url = URL(string: UIApplication.openSettingsURLString) {
UIApplication.shared.open(url)
}
}
Group Notifications
{
"aps": {
"alert": "New message",
"thread-id": "conversation-123"
}
}
Time Sensitive (iOS 15+)
{
"aps": {
"alert": "Your order arrived",
"interruption-level": "time-sensitive"
}
}