Merge pull request #213 from cwalo/cwalo/response-body

Provide response body to failed request errors

Author: donnywals

Sources/TUSKit/TUSAPI.swift

@@ -8,14 +8,14 @@
 import Foundation
 
 /// The errors a TUSAPI can return
-public enum TUSAPIError: Error {
+public enum TUSAPIError: Error, LocalizedError {
     case underlyingError(Error)
     case couldNotFetchStatus
     case couldNotFetchServerInfo
     case couldNotRetrieveOffset
     case couldNotRetrieveLocation
-    case failedRequest(HTTPURLResponse)
-    
+    case failedRequest(HTTPURLResponse, Data?)
+
     public var localizedDescription: String {
         switch self {
         case .underlyingError(let error):
@@ -28,10 +28,18 @@ public enum TUSAPIError: Error {
             return "Could not retrieve offset from response."
         case .couldNotRetrieveLocation:
             return "Could not retrieve location from response."
-        case .failedRequest(let response):
-            return "Failed request with status code \(response.statusCode)."
+        case .failedRequest(let response, let data):
+            if let data, let message = String(data: data, encoding: .utf8) {
+                return "Failed request with status code \(response.statusCode): \(message)"
+            } else {
+                return "Failed request with status code \(response.statusCode)."
+            }
         }
     }
+
+    public var errorDescription: String? {
+        localizedDescription
+    }
 }
 
 /// The status of an upload.
@@ -57,8 +65,9 @@ final class TUSAPI {
     private let sessionDelegate = SessionDataDelegate()
     private let queue = DispatchQueue(label: "com.tus.TUSAPI")
     private var backgroundHandler: (() -> Void)? = nil
-    private var callbacks: [String: (Result<HTTPURLResponse, Error>) -> Void] = [:]
-    
+    private var callbacks: [String: (Result<(Data?, HTTPURLResponse), Error>) -> Void] = [:]
+    private var taskData: [String: Data] = [:]
+
     deinit {
         if session.delegate is SessionDataDelegate {
             session.finishTasksAndInvalidate()
@@ -137,10 +146,10 @@ final class TUSAPI {
         queue.sync {
             callbacks[identifier] = { result in
                 processResult(completion: completion) {
-                    let response =  try result.get()
-                    
+                    let (data, response) =  try result.get()
+
                     guard (200...299).contains(response.statusCode) else {
-                        throw TUSAPIError.failedRequest(response)
+                        throw TUSAPIError.failedRequest(response, data)
                     }
 
                     guard let lengthStr = response.allHeaderFields[caseInsensitive: "upload-Length"] as? String,
@@ -176,10 +185,10 @@ final class TUSAPI {
         queue.sync {
             callbacks[identifier] =  { result in
                 processResult(completion: completion) {
-                    let response = try result.get()
-                    
+                    let (data, response) = try result.get()
+
                     guard (200...299).contains(response.statusCode) else {
-                        throw TUSAPIError.failedRequest(response)
+                        throw TUSAPIError.failedRequest(response, data)
                     }
 
                     guard let location = response.allHeaderFields[caseInsensitive: "location"] as? String,
@@ -281,10 +290,10 @@ final class TUSAPI {
         queue.sync {
             callbacks[metaData.id.uuidString] = { result in
                 processResult(completion: completion) {
-                    let response = try result.get()
-                    
+                    let (data, response) = try result.get()
+
                     guard (200...299).contains(response.statusCode) else {
-                        throw TUSAPIError.failedRequest(response)
+                        throw TUSAPIError.failedRequest(response, data)
                     }
 
                     guard let offsetStr = response.allHeaderFields[caseInsensitive: "upload-offset"] as? String,
@@ -332,7 +341,7 @@ final class TUSAPI {
         queue.sync {
             self.callbacks[metaData.id.uuidString] = { result in
                 processResult(completion: completion) {
-                    let response = try result.get()
+                    let (data, response) = try result.get()
                     guard let offsetStr = response.allHeaderFields[caseInsensitive: "upload-offset"] as? String,
                           let offset = Int(offsetStr) else {
                         throw TUSAPIError.couldNotRetrieveOffset
@@ -349,7 +358,7 @@ final class TUSAPI {
         queue.sync {
             self.callbacks[metadata.id.uuidString] = { result in
                 processResult(completion: completion) {
-                    let response = try result.get()
+                    let (data, response) = try result.get()
                     guard let offsetStr = response.allHeaderFields[caseInsensitive: "upload-offset"] as? String,
                           let offset = Int(offsetStr) else {
                         throw TUSAPIError.couldNotRetrieveOffset
@@ -436,7 +445,15 @@ extension Dictionary {
 private extension TUSAPI {
     final class SessionDataDelegate: NSObject, URLSessionDataDelegate {
         weak var api: TUSAPI?
-        
+
+        func urlSession(_ session: URLSession, dataTask: URLSessionDataTask, didReceive data: Data) {
+            guard let api, let identifier = dataTask.taskDescription else {
+                return
+            }
+
+            api.taskData[identifier, default: Data()].append(data)
+        }
+
         func urlSession(_ session: URLSession, task: URLSessionTask, didCompleteWithError error: Error?) {
             api?.handleCompletionOfTask(task, withError: error)
         }
@@ -454,6 +471,7 @@ private extension TUSAPI {
 
             defer {
                 callbacks.removeValue(forKey: identifier)
+                taskData.removeValue(forKey: identifier)
             }
 
             guard let completion = callbacks[identifier] else {
@@ -469,8 +487,10 @@ private extension TUSAPI {
                 completion(.failure(TUSAPIError.underlyingError(NetworkError.noHTTPURLResponse)))
                 return
             }
-            
-            completion(.success(response))
+
+            let data = taskData[identifier]
+            let success = (data, response)
+            completion(.success(success))
         }
     }
 

Sources/TUSKit/TUSClientError.swift

@@ -1,14 +1,14 @@
 import Foundation
 
 /// The errors that are passed from TUSClient
-public enum TUSClientError: Error {
-    
+public enum TUSClientError: Error, LocalizedError {
+
     case couldNotCopyFile(underlyingError: Error)
     case couldNotStoreFile(underlyingError: Error)
     case fileSizeUnknown
     case couldNotLoadData(underlyingError: Error)
     case couldNotStoreFileMetadata(underlyingError: Error)
-    case couldNotCreateFileOnServer
+    case couldNotCreateFileOnServer(underlyingError: Error)
     case couldNotUploadFile(underlyingError: Error)
     case couldNotGetFileStatus
     case fileSizeMismatchWithServer
@@ -36,8 +36,8 @@ public enum TUSClientError: Error {
             return "Could not load data: \(underlyingError.localizedDescription)"
         case .couldNotStoreFileMetadata(let underlyingError):
             return "Could not store file metadata: \(underlyingError.localizedDescription)"
-        case .couldNotCreateFileOnServer:
-            return "Could not create file on server."
+        case .couldNotCreateFileOnServer(let underlyingError):
+            return "Could not create file on server: (\(underlyingError.localizedDescription))"
         case .couldNotUploadFile(let underlyingError):
             return "Could not upload file: \(underlyingError.localizedDescription)"
         case .couldNotGetFileStatus:
@@ -68,4 +68,8 @@ public enum TUSClientError: Error {
             return "Custom URLSession with background configuration is not supported."
         }
     }
+
+    public var errorDescription: String? {
+        localizedDescription
+    }
 }

Sources/TUSKit/Tasks/CreationTask.swift

@@ -70,7 +70,7 @@ final class CreationTask: IdentifiableTask {
                     } catch let error as TUSClientError {
                         completed(.failure(error))
                     } catch {
-                        completed(.failure(TUSClientError.couldNotCreateFileOnServer))
+                        completed(.failure(TUSClientError.couldNotCreateFileOnServer(underlyingError: error)))
                     }
                 }
             }