oncall-mobile-ios/ntfy/Persistence/Store.swift
2023-11-05 14:00:28 -05:00

274 lines
12 KiB
Swift

import Foundation
import CoreData
import Combine
/// Handles all persistence in the app by storing/loading subscriptions and notifications using Core Data.
/// There are sadly a lot of hacks in here, because I don't quite understand this fully.
class Store: ObservableObject {
static let shared = Store()
static let tag = "Store"
static let appGroup = "group.io.heckel.ntfy" // Must match app group of ntfy = ntfyNSE targets
static let modelName = "ntfy" // Must match .xdatamodeld folder
static let prefKeyDefaultBaseUrl = "defaultBaseUrl"
private let container: NSPersistentContainer
var context: NSManagedObjectContext {
return container.viewContext
}
private var cancellables: Set<AnyCancellable> = []
init(inMemory: Bool = false) {
let storeUrl = (inMemory) ? URL(fileURLWithPath: "/dev/null") : FileManager.default
.containerURL(forSecurityApplicationGroupIdentifier: Store.appGroup)!
.appendingPathComponent("ntfy.sqlite")
let description = NSPersistentStoreDescription(url: storeUrl)
description.setOption(true as NSNumber, forKey: NSPersistentStoreRemoteChangeNotificationPostOptionKey)
// Set up container and observe changes from app extension
container = NSPersistentContainer(name: Store.modelName)
container.persistentStoreDescriptions = [description]
container.loadPersistentStores { description, error in
if let error = error {
Log.e(Store.tag, "Core Data failed to load: \(error.localizedDescription)", error)
}
}
// Shortcut for context
context.automaticallyMergesChangesFromParent = true
context.mergePolicy = NSMergePolicy(merge: .mergeByPropertyStoreTrumpMergePolicyType) // https://stackoverflow.com/a/60362945/1440785
context.transactionAuthor = Bundle.main.bundlePath.hasSuffix(".appex") ? "ntfy.appex" : "ntfy"
// When a remote change comes in (= the app extension updated entities in Core Data),
// we force refresh the view with horrible means. Please help me make this better!
NotificationCenter.default
.publisher(for: .NSPersistentStoreRemoteChange)
.sink { value in
// TODO: this could probably broadcast the name of the channel
// so that only relevant views can update.
Log.d(Store.tag, "Remote change detected, refreshing views", value)
DispatchQueue.main.async {
self.hardRefresh()
}
}
.store(in: &cancellables)
}
func rollbackAndRefresh() {
// Hack: We refresh all objects, since failing to store a notification usually means
// that the app extension stored the notification first. This is a way to update the
// UI properly when it is in the foreground and the app extension stores a notification.
context.rollback()
hardRefresh()
}
func hardRefresh() {
// `refreshAllObjects` only refreshes objects from which the cache is invalid. With a staleness intervall of -1 the cache never invalidates.
// We set the `stalenessInterval` to 0 to make sure that changes in the app extension get processed correctly.
// From: https://www.avanderlee.com/swift/core-data-app-extension-data-sharing/
context.stalenessInterval = 0
context.refreshAllObjects()
context.stalenessInterval = -1
}
// MARK: Subscriptions
func saveSubscription(baseUrl: String, topic: String) -> Subscription {
let subscription = Subscription(context: context)
subscription.baseUrl = baseUrl
subscription.topic = topic
DispatchQueue.main.sync {
Log.d(Store.tag, "Storing subscription baseUrl=\(baseUrl), topic=\(topic)")
try? context.save()
}
return subscription
}
func getSubscription(baseUrl: String, topic: String) -> Subscription? {
let fetchRequest = Subscription.fetchRequest()
let baseUrlPredicate = NSPredicate(format: "baseUrl = %@", baseUrl)
let topicPredicate = NSPredicate(format: "topic = %@", topic)
fetchRequest.predicate = NSCompoundPredicate(andPredicateWithSubpredicates: [baseUrlPredicate, topicPredicate])
return try? context.fetch(fetchRequest).first
}
func getSubscriptions() -> [Subscription]? {
return try? context.fetch(Subscription.fetchRequest())
}
func delete(subscription: Subscription) {
context.delete(subscription)
try? context.save()
}
// MARK: Notifications
func save(notificationFromMessage message: Message, withSubscription subscription: Subscription) {
do {
let notification = Notification(context: context)
notification.id = message.id
notification.time = message.time
notification.message = message.message ?? ""
notification.title = message.title ?? ""
notification.priority = (message.priority != nil && message.priority != 0) ? message.priority! : 3
notification.tags = message.tags?.joined(separator: ",") ?? ""
notification.actions = Actions.shared.encode(message.actions)
notification.click = message.click ?? ""
notification.subscription = subscription
subscription.addToNotifications(notification)
subscription.lastNotificationId = message.id
Log.d(Store.tag, "Storing notifcation with ID \(notification.id ?? "<unknown>")")
try context.save()
} catch let error {
Log.w(Store.tag, "Cannot store notification (fromMessage)", error)
rollbackAndRefresh()
}
}
func delete(notification: Notification) {
Log.d(Store.tag, "Deleting notification \(notification.id ?? "")")
context.delete(notification)
try? context.save()
}
func delete(notifications: Set<Notification>) {
Log.d(Store.tag, "Deleting \(notifications.count) notification(s)")
do {
notifications.forEach { notification in
context.delete(notification)
}
try context.save()
} catch let error {
Log.w(Store.tag, "Cannot delete notification(s)", error)
rollbackAndRefresh()
}
}
func delete(allNotificationsFor subscription: Subscription) {
guard let notifications = subscription.notifications else { return }
Log.d(Store.tag, "Deleting all \(notifications.count) notification(s) for subscription \(subscription.urlString())")
do {
notifications.forEach { notification in
context.delete(notification as! Notification)
}
try context.save()
} catch let error {
Log.w(Store.tag, "Cannot delete notification(s)", error)
rollbackAndRefresh()
}
}
// MARK: Users
func saveUser(baseUrl: String, username: String, password: String) {
do {
let user = getUser(baseUrl: baseUrl) ?? User(context: context)
user.baseUrl = baseUrl
user.username = username
user.password = password
try context.save()
} catch let error {
Log.w(Store.tag, "Cannot store user", error)
rollbackAndRefresh()
}
}
func getUser(baseUrl: String) -> User? {
let request = User.fetchRequest()
request.predicate = NSCompoundPredicate(andPredicateWithSubpredicates: [NSPredicate(format: "baseUrl = %@", baseUrl)])
return try? context.fetch(request).first
}
func delete(user: User) {
context.delete(user)
try? context.save()
}
// MARK: Preferences
func saveDefaultBaseUrl(baseUrl: String?) {
do {
let pref = getPreference(key: Store.prefKeyDefaultBaseUrl) ?? Preference(context: context)
pref.key = Store.prefKeyDefaultBaseUrl
pref.value = baseUrl ?? Config.appBaseUrl
try context.save()
} catch let error {
Log.w(Store.tag, "Cannot store preference", error)
rollbackAndRefresh()
}
}
func getDefaultBaseUrl() -> String {
let baseUrl = getPreference(key: Store.prefKeyDefaultBaseUrl)?.value
if baseUrl == nil || baseUrl?.isEmpty == true {
return Config.appBaseUrl
}
return baseUrl!
}
private func getPreference(key: String) -> Preference? {
let request = Preference.fetchRequest()
request.predicate = NSCompoundPredicate(andPredicateWithSubpredicates: [NSPredicate(format: "key = %@", key)])
return try? context.fetch(request).first
}
}
extension Store {
static let sampleMessages = [
"stats": [
// TODO: Message with action
Message(id: "1", time: 1653048956, event: "message", topic: "stats", message: "In the last 24 hours, hyou had 5,000 users across 13 countries visit your website", title: "Record visitor numbers", priority: 4, tags: ["smile", "server123", "de"], actions: nil),
Message(id: "2", time: 1653058956, event: "message", topic: "stats", message: "201 users/h\n80 IPs", title: "This is a title", priority: 1, tags: [], actions: nil),
Message(id: "3", time: 1643058956, event: "message", topic: "stats", message: "This message does not have a title, but is instead super long. Like really really long. It can't be any longer I think. I mean, there is s 4,000 byte limit of the message, so I guess I have to make this 4,000 bytes long. Or do I? 😁 I don't know. It's quite tedious to come up with something so long, so I'll stop now. Bye!", title: nil, priority: 5, tags: ["facepalm"], actions: nil)
],
"backups": [],
"announcements": [],
"alerts": [],
"playground": []
]
static var preview: Store = {
let store = Store(inMemory: true)
store.context.perform {
// Subscriptions and notifications
sampleMessages.forEach { topic, messages in
store.makeSubscription(store.context, topic, messages)
}
// Users
store.saveUser(baseUrl: "https://ntfy.sh", username: "testuser", password: "testuser")
store.saveUser(baseUrl: "https://ntfy.example.com", username: "phil", password: "phil12")
}
return store
}()
static var previewEmpty: Store = {
return Store(inMemory: true)
}()
@discardableResult
func makeSubscription(_ context: NSManagedObjectContext, _ topic: String, _ messages: [Message]) -> Subscription {
let notifications = messages.map { makeNotification(context, $0) }
let subscription = Subscription(context: context)
subscription.baseUrl = Config.appBaseUrl
subscription.topic = topic
subscription.notifications = NSSet(array: notifications)
return subscription
}
@discardableResult
func makeNotification(_ context: NSManagedObjectContext, _ message: Message) -> Notification {
let notification = Notification(context: context)
notification.id = message.id
notification.time = message.time
notification.message = message.message
notification.title = message.title
notification.priority = message.priority ?? 3
notification.tags = message.tags?.joined(separator: ",") ?? ""
return notification
}
}