[iOS] Create a cache system for images

app-ios/Sources/CommonComponents/Timetable/CircularUserIcon.swift

@@ -0,0 +1,59 @@
+import Foundation
+import SwiftUI
+
+private actor SpeakerIconInMemoryCache {
+    static let shared = SpeakerIconInMemoryCache()
+    private init() {}
+
+    private var cache: [String: Data] = [:]
+
+    func data(urlString: String) -> Data? {
+        return cache[urlString]
+    }
+
+    func set(data: Data, urlString: String) {
+        cache[urlString] = data
+    }
+}
+
+public struct CircularUserIcon: View {
+    let urlString: String
+    @State private var iconData: Data?
+
+    public init(urlString: String) {
+        self.urlString = urlString
+    }
+
+    public var body: some View {
+        Group {
+            if let data = iconData,
+               let uiImage = UIImage(data: data) {
+                Image(uiImage: uiImage)
+                    .resizable()
+            } else {
+                Circle().stroke(Color.gray)
+            }
+        }
+        .clipShape(Circle())
+        .task {
+            if let data = await SpeakerIconInMemoryCache.shared.data(urlString: urlString) {
+                iconData = data
+                return
+            }
+
+            guard let url = URL(string: urlString) else {
+                return
+            }
+            let urlRequest = URLRequest(url: url, cachePolicy: .useProtocolCachePolicy)
+            if let (data, _) = try? await URLSession.shared.data(for: urlRequest) {
+                iconData = data
+                await SpeakerIconInMemoryCache.shared.set(data: data, urlString: urlString)
+            }
+        }
+    }
+}
+
+#Preview {
+    CircularUserIcon(urlString: "https://avatars.githubusercontent.com/u/10727543?s=96&v=4")
+        .frame(width: 32, height: 32)
+}

app-ios/Sources/CommonComponents/Timetable/TimetableCard.swift

@@ -54,18 +54,8 @@ public struct TimetableCard: View {
 
                 ForEach(timetableItem.speakers, id: \.id) { speaker in
                     HStack(spacing: 8) {
-                        Group {
-                            if let url = URL(string: speaker.iconUrl) {
-                                AsyncImage(url: url) {
-                                    $0.image?.resizable()
-                                }
-                            } else {
-                                Circle().stroke(Color.gray)
-                            }
-                        }
-                        .frame(width: 32, height: 32)
-                        .clipShape(Circle())
-
+                        CircularUserIcon(urlString: speaker.iconUrl)
+                            .frame(width: 32, height: 32)
                         Text(speaker.name)
                             .textStyle(.titleSmall)
                             .foregroundStyle(AssetColors.Surface.onSurfaceVariant.swiftUIColor)

app-ios/Sources/ContributorFeature/ContributorListItemView.swift

@@ -1,6 +1,7 @@
 import SwiftUI
 import Theme
 import Model
+import CommonComponents
 
 struct ContributorListItemView: View {
     let contributor: Contributor
@@ -13,11 +14,8 @@ struct ContributorListItemView: View {
             }
         } label: {
             HStack(alignment: .center, spacing: 12) {
-                AsyncImage(url: contributor.iconUrl) {
-                    $0.image?.resizable()
-                }
-                .frame(width: 52, height: 52)
-                .clipShape(Circle())
+                CircularUserIcon(urlString: contributor.iconUrl.absoluteString)
+                    .frame(width: 52, height: 52)
 
                 Text(contributor.userName)
                     .textStyle(.bodyLarge)

app-ios/Sources/StaffFeature/StaffLabel.swift

@@ -1,21 +1,19 @@
 import SwiftUI
 import Theme
+import CommonComponents
 
 struct StaffLabel: View {
     let name: String
     let icon: URL
 
     var body: some View {
         HStack(alignment: .center, spacing: 12) {
-            AsyncImage(url: icon) {
-                $0.image?.resizable()
-            }
-            .frame(width: 52, height: 52)
-            .clipShape(Circle())
-            .overlay(
-                Circle()
-                    .stroke(AssetColors.Outline.outline.swiftUIColor, lineWidth: 1)
-            )
+            CircularUserIcon(urlString: icon.absoluteString)
+                .frame(width: 52, height: 52)
+                .overlay(
+                    Circle()
+                        .stroke(AssetColors.Outline.outline.swiftUIColor, lineWidth: 1)
+                )
 
             Text(name)
                 .textStyle(.bodyLarge)
@@ -27,5 +25,5 @@ struct StaffLabel: View {
 }
 
 #Preview {
-    StaffLabel(name: "hoge", icon: .init(string: "")!)
+    StaffLabel(name: "hoge", icon: .init(string: "https://avatars.githubusercontent.com/u/10727543?s=156&v=4")!)
 }

app-ios/Sources/TimetableDetailFeature/TimetableDetailView.swift

@@ -109,13 +109,8 @@ public struct TimetableDetailView: View {
 
             ForEach(store.timetableItem.speakers, id: \.id) { speaker in
                 HStack(spacing: 12) {
-                    if let url = URL(string: speaker.iconUrl) {
-                        AsyncImage(url: url) {
-                            $0.image?.resizable()
-                        }
+                    CircularUserIcon(urlString: speaker.iconUrl)
                         .frame(width: 52, height: 52)
-                        .clipShape(Circle())
-                    }
 
                     VStack(alignment: .leading, spacing: 8) {
                         Text(speaker.name)