feat: Optimization for Chunk-Downloads (#27)

alibaba · Jan 8, 2024 · 28a0561 · 28a0561
1 parent 7cc40c3
commit 28a0561
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Showing 3 changed files with 10 additions and 4 deletions.
diff --git a/Sources/AliyunpanSDK/AliyunpanCredentials/AliyunpanAppJumper.swift b/Sources/AliyunpanSDK/AliyunpanCredentials/AliyunpanAppJumper.swift
@@ -18,7 +18,7 @@ class AliyunpanAppJumper {
     }
 
     func jump(to url: URL) async throws -> String {
-        guard Platform.canOpenURL(url) else {
+        guard await Platform.canOpenURL(url) else {
             throw AliyunpanError.AuthorizeError.notInstalledApp
         }
 

diff --git a/Sources/AliyunpanSDK/HTTPRequest/Download/AliyunpanDownloadTask.swift b/Sources/AliyunpanSDK/HTTPRequest/Download/AliyunpanDownloadTask.swift
@@ -73,7 +73,7 @@ public class AliyunpanDownloadTask: NSObject, Identifiable {
     public let file: AliyunpanFile
     let destination: URL
 
-    private let chunkSize = 4_000_000
+    private let chunkSize: Int64
     private let downloadURLActor = DownloadURLActor()
     private let fileManager = FileManager.default
 
@@ -88,12 +88,17 @@ public class AliyunpanDownloadTask: NSObject, Identifiable {
     private(set) var urlSession: URLSession?
 
     private var writedSize: Int64 = 0
+
+    @ThreadSafe
     var unfinishedChunks: [AliyunpanDownloadChunk] = []
 
     init(file: AliyunpanFile, destination: URL, delegate: AliyunpanDownloadTaskDelegate?) {
         self.file = file
         self.destination = destination
         self.delegate = delegate
+        // 根据文件大小动态设置分片大小，来降低内存占用
+        // 最小为4M
+        self.chunkSize = max(4_000_000, (file.size ?? 0) / 1000)
         super.init()
         delegate?.downloadTask(self, didUpdateState: state)
     }
@@ -176,7 +181,7 @@ extension AliyunpanDownloadTask {
     }
 
     var chunks: [AliyunpanDownloadChunk] {
-        stride(from: 0, to: totalSize, by: chunkSize).map {
+        stride(from: 0, to: totalSize, by: Int64.Stride(chunkSize)).map {
             AliyunpanDownloadChunk(start: $0, end: min($0 + Int64(chunkSize), totalSize))
         }
     }

diff --git a/Sources/AliyunpanSDK/Platform.swift b/Sources/AliyunpanSDK/Platform.swift
@@ -18,7 +18,7 @@ import TVUIKit
 #endif
 
 class Platform {
-
+    @MainActor
     static func canOpenURL(_ url: URL) -> Bool {
 #if canImport(UIKit) || canImport(TVUIKit)
         return UIApplication.shared.canOpenURL(url)
@@ -29,6 +29,7 @@ class Platform {
 #endif
     }
 
+    @MainActor
     static func open(_ url: URL) async {
 #if canImport(UIKit) || canImport(TVUIKit)
         await UIApplication.shared.open(url)