iOS client for Grain
grain.social
ios
photography
atproto
perf: debounce UserDefaults writes in ViewedStoryStorage
Rapid story tapping was writing UserDefaults on every view, O(n²) in
tests and wasteful in production. Coalesce writes with a 1s debounce;
cleanup() still flushes immediately.
+12
-1
+12
-1
Grain/Utilities/ViewedStoryStorage.swift
+12
-1
Grain/Utilities/ViewedStoryStorage.swift
···
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9
private static let urisKey = "viewedStoryUris"
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private static let authorKey = "viewedStoryAuthors"
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+
private var saveTask: Task<Void, Never>?
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+
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init() {
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#if DEBUG
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Self.wipeDefaults()
···
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} else {
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authorLastViewed[authorDid] = createdAt
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}
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-
save()
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+
scheduleSave()
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}
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/// Check if a specific story has been viewed.
···
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let decoded = try? JSONDecoder().decode([String: String].self, from: data)
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{
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authorLastViewed = decoded
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+
}
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+
}
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+
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+
private func scheduleSave() {
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saveTask?.cancel()
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+
saveTask = Task { [weak self] in
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+
try? await Task.sleep(for: .seconds(1))
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+
guard !Task.isCancelled else { return }
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+
self?.save()
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}
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}
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