fix download progress bug

close Moya#715

Demo/Tests/MoyaProviderSpec.swift

@@ -587,5 +587,51 @@ class MoyaProviderSpec: QuickSpec {
                 expect(underlyingIsCancelled).to(beTrue())
             }
         }
+
+        describe("a provider with progress tracking") {
+            var provider: MoyaProvider<GitHubUserContent>!
+            beforeEach {
+
+                //delete downloaded filed before each test
+                let directory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0]
+                let file = directory.appendingPathComponent("logo_github.png")
+                try? FileManager.default.removeItem(at: file)
+
+                //`responseTime(-4)` equals to 1000 bytes at a time. The sample data is 4000 bytes.
+                OHHTTPStubs.stubRequests(passingTest: {$0.url!.path.hasSuffix("logo_github.png")}) { _ in
+                    return OHHTTPStubsResponse(data: GitHubUserContent.downloadMoyaWebContent("logo_github.png").sampleData, statusCode: 200, headers: nil).responseTime(-4)
+                }
+                provider = MoyaProvidesr<GitHubUserContent>()
+            }
+
+            it("tracks progress of request") {
+
+                let target: GitHubUserContent = .downloadMoyaWebContent("logo_github.png")
+
+                var progressValues: [Double] = []
+                var completedValues: [Bool] = []
+                var error: Moya.Error?
+
+                waitUntil(timeout: 5.0) { done in
+                    let progressClosure: ProgressBlock = { progress in
+                        progressValues.append(progress.progress)
+                        completedValues.append(progress.completed)
+                    }
+
+                    let progressCompletionClosure: Completion = { (result) in
+                        if case .failure(let err) = result {
+                            error = err
+                        }
+                        done()
+                    }
+
+                    provider.request(target, queue: nil, progress: progressClosure, completion: progressCompletionClosure)
+                }
+
+                expect(error).to(beNil())
+                expect(progressValues) == [0.25, 0.5, 0.75, 1.0, 1.0]
+                expect(completedValues) == [false, false, false, false, true]
+            }
+        }
     }
 }

Demo/Tests/TestHelpers.swift

@@ -87,3 +87,52 @@ enum HTTPBin: TargetType {
         }
     }
 }
+
+public enum GitHubUserContent {
+    case downloadMoyaWebContent(String)
+}
+
+extension GitHubUserContent: TargetType {
+    public var baseURL: URL { return URL(string: "https://raw.githubusercontent.com")! }
+    public var path: String {
+        switch self {
+        case .downloadMoyaWebContent(let contentPath):
+            return "/Moya/Moya/master/web/\(contentPath)"
+        }
+    }
+    public var method: Moya.Method {
+        switch self {
+        case .downloadMoyaWebContent:
+            return .get
+        }
+    }
+    public var parameters: [String: Any]? {
+        switch self {
+        case .downloadMoyaWebContent:
+            return nil
+        }
+    }
+    public var task: Task {
+        switch self {
+        case .downloadMoyaWebContent:
+            return .download(.request(DefaultDownloadDestination))
+        }
+    }
+    public var sampleData: Data {
+        switch self {
+        case .downloadMoyaWebContent:
+            return Data(count: 4000)
+        }
+    }
+
+}
+
+private let DefaultDownloadDestination: DownloadDestination = { temporaryURL, response in
+    let directoryURLs = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)
+
+    if !directoryURLs.isEmpty {
+        return (directoryURLs[0].appendingPathComponent(response.suggestedFilename!), [])
+    }
+
+    return (temporaryURL, [])
+}

Source/Moya+Internal.swift

@@ -225,6 +225,18 @@ private extension MoyaProvider {
                 completion(result)
             })
 
+            if let dataRequest = dataRequest as? T {
+                progressAlamoRequest = dataRequest
+            }
+        } else if var dataRequest = progressAlamoRequest as? DownloadRequest {
+            dataRequest = dataRequest.response(queue: queue, completionHandler: { handler in
+                let result = convertResponseToResult(handler.response, request: handler.request, data: nil, error: handler.error)
+                // Inform all plugins about the response
+                plugins.forEach { $0.didReceiveResponse(result, target: target) }
+                progressCompletion?(ProgressResponse(response: result.value))
+                completion(result)
+            })
+
             if let dataRequest = dataRequest as? T {
                 progressAlamoRequest = dataRequest
             }