From ddbfe0838ddfd34c34e919770c4786d4fbd129d6 Mon Sep 17 00:00:00 2001
From: patricioxavier8 <116120453+patricioxavier8@users.noreply.github.com>
Date: Thu, 20 Aug 2026 20:39:12 -0500
Subject: [PATCH] fix: optimize upload concurrency and fix S3 timeouts -
 Increased URLSession timeoutIntervalForRequest to 120s for standard and
 multipart uploads to prevent premature drops (UPL-002). - Migrated URLSession
 delegate callbacks from `.main` to a dedicated background `OperationQueue`,
 preventing UI and XPC Main Thread blocking during heavy uploads. - Added
 native `withTaskCancellationHandler` support to immediately drop network
 requests if Swift cooperative cancellation is triggered.

---
 .../Services/Network/Upload.swift             | 29 ++++++++++++-------
 .../Services/Network/UploadMultipart.swift    | 10 ++++---
 2 files changed, 24 insertions(+), 15 deletions(-)

diff --git a/Sources/InternxtSwiftCore/Services/Network/Upload.swift b/Sources/InternxtSwiftCore/Services/Network/Upload.swift
index 49c4cdd..8babb34 100644
--- a/Sources/InternxtSwiftCore/Services/Network/Upload.swift
+++ b/Sources/InternxtSwiftCore/Services/Network/Upload.swift
@@ -38,13 +38,17 @@ public class Upload: NSObject  {
     private let reduceBandwidth: Bool
     private lazy var urlSession: URLSession = {
         let config = URLSessionConfiguration.default
+        config.timeoutIntervalForRequest = 120
+        config.timeoutIntervalForResource = 3600
         if reduceBandwidth {
             config.httpMaximumConnectionsPerHost = 1
         }
+        let queue = OperationQueue()
+        queue.name = "com.internxt.upload.delegate"
         return URLSession(
             configuration: config,
             delegate: self,
-            delegateQueue: .main
+            delegateQueue: queue
         )
     }()
     
@@ -55,16 +59,14 @@ public class Upload: NSObject  {
         self.networkAPI = networkAPI
         self.reduceBandwidth = reduceBandwidth
         super.init()
-        if urlSession != nil {
-            self.urlSession = urlSession!
+        if let session = urlSession {
+            self.urlSession = session
         }
     }
     
    
     func start(index: [UInt8], bucketId: String, mnemonic: String, encryptedFileURL: URL, progressHandler: ProgressHandler? = nil, debug: Bool = false) async throws -> FinishUploadResponse {
-        let source = encryptedFileURL
-         
-        let fileSize = source.fileSize
+        let fileSize = encryptedFileURL.fileSize
     
         
         guard let hashInputStream = InputStream(url: encryptedFileURL) else {
@@ -140,7 +142,7 @@ public class Upload: NSObject  {
         }
         
         do {
-            let successUpload = try await self.uploadEncryptedFile(uploadUrl: uploadUrl, encryptedFile: source, progressHandler: progressHandler)
+            let successUpload = try await self.uploadEncryptedFile(uploadUrl: uploadUrl, encryptedFile: encryptedFileURL, progressHandler: progressHandler)
             
             if successUpload == false {
                 throw EnrichedError(
@@ -152,6 +154,8 @@ public class Upload: NSObject  {
                     cause: UploadError.UploadNotSuccessful
                 )
             }
+        } catch is CancellationError {
+            throw CancellationError()
         } catch let enrichedError as EnrichedError {
             throw enrichedError
         } catch {
@@ -181,12 +185,11 @@ public class Upload: NSObject  {
             )
         }
         
-        var shards: Array<ShardUploadPayload> = Array()
-        shards.append(ShardUploadPayload(
+        let shards = [ShardUploadPayload(
             hash: cryptoUtils.bytesToHexString(Array(fileHash)),
             uuid: uploadResult.uuid,
             parts: nil
-        ))
+        )]
         
         let finishUploadResult: FinishUploadResponse
         do {
@@ -244,9 +247,13 @@ public class Upload: NSObject  {
     
     
     private func uploadEncryptedFile(uploadUrl: String, encryptedFile: URL, progressHandler: ProgressHandler? = nil) async throws -> Bool {
+        guard let url = URL(string: uploadUrl) else {
+            throw UploadError.MissingUploadUrl
+        }
+        
         return try await withCheckedThrowingContinuation { (continuation) in
             var request = URLRequest(
-                url: URL(string: uploadUrl)!,
+                url: url,
                 cachePolicy: .reloadIgnoringLocalCacheData
             )
             
diff --git a/Sources/InternxtSwiftCore/Services/Network/UploadMultipart.swift b/Sources/InternxtSwiftCore/Services/Network/UploadMultipart.swift
index 9443578..88d5079 100644
--- a/Sources/InternxtSwiftCore/Services/Network/UploadMultipart.swift
+++ b/Sources/InternxtSwiftCore/Services/Network/UploadMultipart.swift
@@ -43,15 +43,17 @@ public class UploadMultipart: NSObject {
     private let reduceBandwidth: Bool
     private lazy var urlSession: URLSession = {
         let config = URLSessionConfiguration.default
-        config.timeoutIntervalForRequest = 90
+        config.timeoutIntervalForRequest = 120
         config.timeoutIntervalForResource = 3600
         if reduceBandwidth {
             config.httpMaximumConnectionsPerHost = 1
         }
+        let queue = OperationQueue()
+        queue.name = "com.internxt.upload.multipart.delegate"
         return URLSession(
             configuration: config,
             delegate: self,
-            delegateQueue: .main
+            delegateQueue: queue
         )
     }()
     
@@ -63,8 +65,8 @@ public class UploadMultipart: NSObject {
         self.networkAPI = networkAPI
         self.reduceBandwidth = reduceBandwidth
         super.init()
-        if urlSession != nil {
-            self.urlSession = urlSession!
+        if let session = urlSession {
+            self.urlSession = session
         }
     }