feat: add helper methods to ParseFileTransferable protocol (#411)

* feat: add helper methods to ParseFileTransferable protocol

* add more tests

CHANGELOG.md

@@ -1,15 +1,23 @@
 # Parse-Swift Changelog
 
 ### main
-[Full Changelog](https://github.com/parse-community/Parse-Swift/compare/4.12.0...main)
+[Full Changelog](https://github.com/parse-community/Parse-Swift/compare/4.13.0...main)
 * _Contributing to this repo? Add info about your change here to be included in the next release_
 
+### 4.13.0
+[Full Changelog](https://github.com/parse-community/Parse-Swift/compare/4.12.0...4.13.0)
+
+__New features__
+- Add helper methods to ParseFileTransferable protocol to assist with creating propper responses to file uploads ([#411](https://github.com/parse-community/Parse-Swift/pull/411)), thanks to [Corey Baker](https://github.com/cbaker6).
+
+__Fixes__
+- Remove cached error responses when decoding errors occur ([#411](https://github.com/parse-community/Parse-Swift/pull/411)), thanks to [Corey Baker](https://github.com/cbaker6).
+
 ### 4.12.0
 [Full Changelog](https://github.com/parse-community/Parse-Swift/compare/4.11.0...4.12.0)
 
 __New features__
-- Add the ParseFileTransferable protocol for overriding the default transfer behavior for ParseFile's. Allows for direct uploads to other file storage
- providers ([#408](https://github.com/parse-community/Parse-Swift/pull/408)), thanks to [Corey Baker](https://github.com/cbaker6).
+- Add the ParseFileTransferable protocol for overriding the default transfer behavior for ParseFile's. Allows for direct uploads to other file storage providers ([#410](https://github.com/parse-community/Parse-Swift/pull/410)), thanks to [Corey Baker](https://github.com/cbaker6).
 - Add the become method to ParseInstallation which allows any ParseInstallation to be copied to the current installation. This method can be used to migrate any ParseInstallation to the current installation in the Swift SDK  ([#407](https://github.com/parse-community/Parse-Swift/pull/407)), thanks to [Corey Baker](https://github.com/cbaker6).
 
 __Fixes__

ParseSwift.xcodeproj/project.pbxproj

@@ -327,6 +327,9 @@
 		704E781D28CFFAF80075F952 /* ParseFileDefaultTransfer.swift in Sources */ = {isa = PBXBuildFile; fileRef = 704E781B28CFFAF80075F952 /* ParseFileDefaultTransfer.swift */; };
 		704E781E28CFFAF80075F952 /* ParseFileDefaultTransfer.swift in Sources */ = {isa = PBXBuildFile; fileRef = 704E781B28CFFAF80075F952 /* ParseFileDefaultTransfer.swift */; };
 		704E781F28CFFAF80075F952 /* ParseFileDefaultTransfer.swift in Sources */ = {isa = PBXBuildFile; fileRef = 704E781B28CFFAF80075F952 /* ParseFileDefaultTransfer.swift */; };
+		704E782128D0D73E0075F952 /* ParseFileTransferableTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 704E782028D0D73E0075F952 /* ParseFileTransferableTests.swift */; };
+		704E782228D0D73E0075F952 /* ParseFileTransferableTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 704E782028D0D73E0075F952 /* ParseFileTransferableTests.swift */; };
+		704E782328D0D73E0075F952 /* ParseFileTransferableTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 704E782028D0D73E0075F952 /* ParseFileTransferableTests.swift */; };
 		705025992842FD3B008D6624 /* ParseCLPTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 705025982842FD3B008D6624 /* ParseCLPTests.swift */; };
 		7050259A2842FD3B008D6624 /* ParseCLPTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 705025982842FD3B008D6624 /* ParseCLPTests.swift */; };
 		7050259B2842FD3B008D6624 /* ParseCLPTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 705025982842FD3B008D6624 /* ParseCLPTests.swift */; };
@@ -1244,6 +1247,7 @@
 		704C886B28BE69A8008E6B01 /* ParseConfiguration.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ParseConfiguration.swift; sourceTree = "<group>"; };
 		704E781628CFD8A00075F952 /* ParseFileTransferable.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ParseFileTransferable.swift; sourceTree = "<group>"; };
 		704E781B28CFFAF80075F952 /* ParseFileDefaultTransfer.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ParseFileDefaultTransfer.swift; sourceTree = "<group>"; };
+		704E782028D0D73E0075F952 /* ParseFileTransferableTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ParseFileTransferableTests.swift; sourceTree = "<group>"; };
 		705025982842FD3B008D6624 /* ParseCLPTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ParseCLPTests.swift; sourceTree = "<group>"; };
 		7050259C2843F0CF008D6624 /* ParseSchemaAsyncTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ParseSchemaAsyncTests.swift; sourceTree = "<group>"; };
 		705025A02843F0E7008D6624 /* ParseSchemaCombineTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ParseSchemaCombineTests.swift; sourceTree = "<group>"; };
@@ -1620,6 +1624,7 @@
 				7044C1F825C5CFAB0011F6E7 /* ParseFileCombineTests.swift */,
 				705A99F8259807F900B3547F /* ParseFileManagerTests.swift */,
 				705727882593FF8000F0ADD5 /* ParseFileTests.swift */,
+				704E782028D0D73E0075F952 /* ParseFileTransferableTests.swift */,
 				70BC0B32251903D1001556DB /* ParseGeoPointTests.swift */,
 				70F03A592780EAB000E5AFB4 /* ParseGitHubCombineTests.swift */,
 				70F03A5D2780EAC700E5AFB4 /* ParseGitHubTests.swift */,
@@ -2926,6 +2931,7 @@
 				7044C20625C5D6780011F6E7 /* ParseQueryCombineTests.swift in Sources */,
 				70C5508525B4A68700B5DBC2 /* ParseOperationTests.swift in Sources */,
 				7023800F2747FCCD00EFC443 /* ExtensionsTests.swift in Sources */,
+				704E782128D0D73E0075F952 /* ParseFileTransferableTests.swift in Sources */,
 				917BA43E2703E84000F8D747 /* ParseOperationAsyncTests.swift in Sources */,
 				7037DAB226384DE1005D7E62 /* TestParseEncoder.swift in Sources */,
 				7004C24D25B69207005E0AD9 /* ParseRoleTests.swift in Sources */,
@@ -3246,6 +3252,7 @@
 				7044C20825C5D6780011F6E7 /* ParseQueryCombineTests.swift in Sources */,
 				70C5508725B4A68700B5DBC2 /* ParseOperationTests.swift in Sources */,
 				702380112747FCCD00EFC443 /* ExtensionsTests.swift in Sources */,
+				704E782328D0D73E0075F952 /* ParseFileTransferableTests.swift in Sources */,
 				917BA4402703E84000F8D747 /* ParseOperationAsyncTests.swift in Sources */,
 				7037DAB426384DE1005D7E62 /* TestParseEncoder.swift in Sources */,
 				7004C26125B6920B005E0AD9 /* ParseRoleTests.swift in Sources */,
@@ -3369,6 +3376,7 @@
 				7044C20725C5D6780011F6E7 /* ParseQueryCombineTests.swift in Sources */,
 				70C5508625B4A68700B5DBC2 /* ParseOperationTests.swift in Sources */,
 				702380102747FCCD00EFC443 /* ExtensionsTests.swift in Sources */,
+				704E782228D0D73E0075F952 /* ParseFileTransferableTests.swift in Sources */,
 				917BA43F2703E84000F8D747 /* ParseOperationAsyncTests.swift in Sources */,
 				7037DAB326384DE1005D7E62 /* TestParseEncoder.swift in Sources */,
 				7004C25725B6920A005E0AD9 /* ParseRoleTests.swift in Sources */,

Sources/ParseSwift/API/Responses.swift

@@ -137,7 +137,7 @@ internal struct LoginSignupResponse: Codable {
 }
 
 // MARK: ParseFile
-internal struct FileUploadResponse: Decodable {
+internal struct FileUploadResponse: Codable {
     let name: String
     let url: URL
 

Sources/ParseSwift/Extensions/URLSession.swift

@@ -95,13 +95,15 @@ internal extension URLSession {
                     do {
                         responseData = try ParseCoding.jsonEncoder().encode(pushStatus)
                     } catch {
+                        URLSession.parse.configuration.urlCache?.removeCachedResponse(for: request)
                         return .failure(ParseError(code: .unknownError, message: error.localizedDescription))
                     }
                 }
             }
             do {
                 return try .success(mapper(responseData))
             } catch {
+                URLSession.parse.configuration.urlCache?.removeCachedResponse(for: request)
                 guard let parseError = error as? ParseError else {
                     guard JSONSerialization.isValidJSONObject(responseData),
                           let json = try? JSONSerialization
@@ -226,26 +228,42 @@ internal extension URLSession {
     ) {
         var task: URLSessionTask?
         if let data = data {
-            task = ParseSwift
-                .configuration
-                .parseFileTransfer
-                .upload(with: request, from: data) { (responseData, urlResponse, responseError) in
-                completion(self.makeResult(request: request,
-                                           responseData: responseData,
-                                           urlResponse: urlResponse,
-                                           responseError: responseError,
-                                           mapper: mapper))
+            do {
+                task = try ParseSwift
+                    .configuration
+                    .parseFileTransfer
+                    .upload(with: request,
+                            from: data) { (responseData, urlResponse, updatedRequest, responseError) in
+                    completion(self.makeResult(request: updatedRequest ?? request,
+                                               responseData: responseData,
+                                               urlResponse: urlResponse,
+                                               responseError: responseError,
+                                               mapper: mapper))
+                }
+            } catch {
+                let defaultError = ParseError(code: .unknownError,
+                                              message: "Error uploading file: \(String(describing: error))")
+                let parseError = error as? ParseError ?? defaultError
+                completion(.failure(parseError))
             }
         } else if let file = file {
-            task = ParseSwift
-                .configuration
-                .parseFileTransfer
-                .upload(with: request, fromFile: file) { (responseData, urlResponse, responseError) in
-                completion(self.makeResult(request: request,
-                                           responseData: responseData,
-                                           urlResponse: urlResponse,
-                                           responseError: responseError,
-                                           mapper: mapper))
+            do {
+                task = try ParseSwift
+                    .configuration
+                    .parseFileTransfer
+                    .upload(with: request,
+                            fromFile: file) { (responseData, urlResponse, updatedRequest, responseError) in
+                    completion(self.makeResult(request: updatedRequest ?? request,
+                                               responseData: responseData,
+                                               urlResponse: urlResponse,
+                                               responseError: responseError,
+                                               mapper: mapper))
+                }
+            } catch {
+                let defaultError = ParseError(code: .unknownError,
+                                              message: "Error uploading file: \(String(describing: error))")
+                let parseError = error as? ParseError ?? defaultError
+                completion(.failure(parseError))
             }
         } else {
             completion(.failure(ParseError(code: .unknownError, message: "data and file both cannot be nil")))

Sources/ParseSwift/Protocols/ParseFileTransferable.swift

@@ -23,11 +23,14 @@ public protocol ParseFileTransferable: AnyObject {
      request type, and so on.
      - parameter fileURL: The URL of the file to upload.
      - parameter completion: The completion handler to call when the load request
-     is complete. This handler is executed on the delegate queue.
+     is complete. Should be in the form `(Data?, URLResponse?, URLRequest?, Error?)`.
+    `Data` and `URLResponse` should be created using `makeSuccessfulUploadResponse()`.
+    `URLRequest` is the request used to upload the file if available. `Error` is any error that occured
+     that prevented the file upload.
      */
     func upload(with request: URLRequest,
                 fromFile fileURL: URL,
-                completion: @escaping (Data?, URLResponse?, Error?) -> Void) -> URLSessionUploadTask
+                completion: @escaping (Data?, URLResponse?, URLRequest?, Error?) -> Void) throws -> URLSessionUploadTask
 
     /**
      Creates a task that performs an HTTP request for the specified URL request
@@ -36,23 +39,77 @@ public protocol ParseFileTransferable: AnyObject {
      request type, and so on.
      - parameter bodyData: The body data for the request.
      - parameter completion: The completion handler to call when the load request
-     is complete. This handler is executed on the delegate queue.
+     is complete. Should be in the form `(Data?, URLResponse?, URLRequest?, Error?)`.
+    `Data` and `URLResponse` should be created using `makeSuccessfulUploadResponse()`.
+    `URLRequest` is the request used to upload the file if available. `Error` is any error that occured
+     that prevented the file upload.
      */
     func upload(with request: URLRequest,
                 from bodyData: Data?,
-                completion: @escaping (Data?, URLResponse?, Error?) -> Void) -> URLSessionUploadTask
+                completion: @escaping (Data?, URLResponse?, URLRequest?, Error?) -> Void) throws -> URLSessionUploadTask
+
+    /**
+     Compose a valid file upload response with a name and url.
+     
+     Use this method after uploading a file to any file storage to
+     respond to the Swift SDK upload request.
+     - parameter name: The name of the file.
+     - parameter url: The url of the file that was stored.
+     - returns: A tuple of `(Data, HTTPURLResponse?)` where `Data` is the
+     JSON encoded file upload response and `HTTPURLResponse` is the metadata
+     associated with the response to the load request.
+     */
+    func makeSuccessfulUploadResponse(_ name: String, url: URL) throws -> (Data, HTTPURLResponse?)
+
+    /**
+     Compose a dummy upload task.
+     
+     Use this method if you do not need the Parse Swift SDK to start
+     your upload task for you.
+     - returns: A dummy upload task that starts an upload of zero bytes
+     to localhost.
+     - throws: An error of type `ParseError`.
+     */
+    func makeDummyUploadTask() throws -> URLSessionUploadTask
 }
 
+// MARK: Default Implementation - Internal
 extension ParseFileTransferable {
     func upload(with request: URLRequest,
                 fromFile fileURL: URL,
-                completion: @escaping (Data?, URLResponse?, Error?) -> Void) -> URLSessionUploadTask {
-        URLSession.parse.uploadTask(with: request, fromFile: fileURL, completionHandler: completion)
+                // swiftlint:disable:next line_length
+                completion: @escaping (Data?, URLResponse?, URLRequest?, Error?) -> Void) throws -> URLSessionUploadTask {
+        URLSession.parse.uploadTask(with: request, fromFile: fileURL) { (data, response, error) in
+            completion(data, response, request, error)
+        }
     }
 
     func upload(with request: URLRequest,
                 from bodyData: Data?,
-                completion: @escaping (Data?, URLResponse?, Error?) -> Void) -> URLSessionUploadTask {
-        URLSession.parse.uploadTask(with: request, from: bodyData, completionHandler: completion)
+                // swiftlint:disable:next line_length
+                completion: @escaping (Data?, URLResponse?, URLRequest?, Error?) -> Void) throws -> URLSessionUploadTask {
+        URLSession.parse.uploadTask(with: request, from: bodyData) { (data, response, error) in
+            completion(data, response, request, error)
+        }
+    }
+}
+
+// MARK: Default Implementation - Public
+public extension ParseFileTransferable {
+    func makeSuccessfulUploadResponse(_ name: String, url: URL) throws -> (Data, HTTPURLResponse?) {
+        let responseData = FileUploadResponse(name: name, url: url)
+        let response = HTTPURLResponse(url: url,
+                                       statusCode: 200,
+                                       httpVersion: nil,
+                                       headerFields: nil)
+        let encodedResponseData = try ParseCoding.jsonEncoder().encode(responseData)
+        return (encodedResponseData, response)
+    }
+
+    func makeDummyUploadTask() throws -> URLSessionUploadTask {
+        guard let url = URL(string: "http://localhost") else {
+            throw ParseError(code: .unknownError, message: "Could not create URL")
+        }
+        return URLSession.shared.uploadTask(with: .init(url: url), from: Data())
     }
 }