feat: 프로필 이미지 메모리 캐시 저장소 추가

Author: opficdev

Application/DevLogData/Sources/DataAssembler.swift

@@ -94,6 +94,13 @@ public final class DataAssembler: Assembler {
             UserDataRepositoryImpl(userService: container.resolve(UserService.self))
         }
 
+        container.register(ProfileImageDataRepository.self) {
+            ProfileImageDataRepositoryImpl(
+                service: container.resolve(ProfileImageDataService.self),
+                store: container.resolve(MemoryCacheStore.self)
+            )
+        }
+
         container.register(AnalyticsRepository.self) {
             AnalyticsRepositoryImpl(
                 analyticsService: container.resolve(AnalyticsService.self)

Application/DevLogData/Sources/Protocol/ProfileImageDataService.swift

@@ -0,0 +1,12 @@
+//
+//  ProfileImageDataService.swift
+//  DevLogData
+//
+//  Created by opfic on 6/11/26.
+//
+
+import Foundation
+
+public protocol ProfileImageDataService {
+    func fetchImageData(from url: URL) async throws -> Data
+}

Application/DevLogData/Sources/Repository/ProfileImageDataRepositoryImpl.swift

@@ -0,0 +1,39 @@
+//
+//  ProfileImageDataRepositoryImpl.swift
+//  DevLogData
+//
+//  Created by opfic on 6/11/26.
+//
+
+import Foundation
+import DevLogDomain
+
+public final class ProfileImageDataRepositoryImpl: ProfileImageDataRepository {
+    private let service: ProfileImageDataService
+    private let store: MemoryCacheStore
+
+    public init(
+        service: ProfileImageDataService,
+        store: MemoryCacheStore
+    ) {
+        self.service = service
+        self.store = store
+    }
+
+    public func fetchImageData(from url: URL) async throws -> Data {
+        do {
+            let data = try await service.fetchImageData(from: url)
+            store.setValue(data, forKey: Self.cacheKey(for: url))
+            return data
+        } catch {
+            if let data: Data = store.value(forKey: Self.cacheKey(for: url)) {
+                return data
+            }
+            throw error
+        }
+    }
+
+    private static func cacheKey(for url: URL) -> String {
+        "profileImageData:\(url.absoluteString)"
+    }
+}

Application/DevLogData/Tests/Repository/ProfileImageDataRepositoryImplTests.swift

@@ -0,0 +1,89 @@
+//
+//  ProfileImageDataRepositoryImplTests.swift
+//  DevLogDataTests
+//
+//  Created by opfic on 6/11/26.
+//
+
+import Foundation
+import Testing
+@testable import DevLogData
+
+struct ProfileImageDataRepositoryImplTests {
+    @Test("캐시가 있어도 원격 이미지 데이터를 다시 요청하고 성공 데이터를 저장한다")
+    func 캐시가_있어도_원격_이미지_데이터를_다시_요청하고_성공_데이터를_저장한다() async throws {
+        let cachedData = Data([1, 2, 3])
+        let remoteData = Data([4, 5, 6])
+        let service = ProfileImageDataServiceSpy(data: cachedData)
+        let store = ProfileImageMemoryCacheStoreSpy()
+        let repository = ProfileImageDataRepositoryImpl(service: service, store: store)
+        let url = URL(string: "https://example.com/avatar.png")!
+
+        _ = try await repository.fetchImageData(from: url)
+        service.data = remoteData
+        let data = try await repository.fetchImageData(from: url)
+
+        #expect(data == remoteData)
+        #expect(service.calledURLs == [url, url])
+        #expect(store.storedData == remoteData)
+    }
+
+    @Test("원격 이미지 요청 실패 시 메모리 캐시 데이터를 반환한다")
+    func 원격_이미지_요청_실패_시_메모리_캐시_데이터를_반환한다() async throws {
+        let cachedData = Data([1, 2, 3])
+        let service = ProfileImageDataServiceSpy(data: cachedData)
+        let store = ProfileImageMemoryCacheStoreSpy()
+        let repository = ProfileImageDataRepositoryImpl(service: service, store: store)
+        let url = URL(string: "https://example.com/avatar.png")!
+
+        _ = try await repository.fetchImageData(from: url)
+        service.error = ProfileImageDataRepositoryImplTestsError.serviceFailed
+        let data = try await repository.fetchImageData(from: url)
+
+        #expect(data == cachedData)
+        #expect(service.calledURLs == [url, url])
+    }
+}
+
+private final class ProfileImageDataServiceSpy: ProfileImageDataService {
+    var data: Data
+    var error: Error?
+    private(set) var calledURLs: [URL] = []
+
+    init(data: Data) {
+        self.data = data
+    }
+
+    func fetchImageData(from url: URL) async throws -> Data {
+        calledURLs.append(url)
+
+        if let error {
+            throw error
+        }
+
+        return data
+    }
+}
+
+private final class ProfileImageMemoryCacheStoreSpy: MemoryCacheStore {
+    private var values = [String: Any]()
+    private(set) var storedData: Data?
+
+    func value<T: Codable>(forKey key: String) -> T? {
+        values[key] as? T
+    }
+
+    func setValue<T: Codable>(_ value: T?, forKey key: String) {
+        guard let value else {
+            values.removeValue(forKey: key)
+            return
+        }
+
+        values[key] = value
+        storedData = value as? Data
+    }
+}
+
+private enum ProfileImageDataRepositoryImplTestsError: Error {
+    case serviceFailed
+}