Merge pull request #8 from johnno1962/xcode-11-beta3

Combine examples

Other Projects/Combine using GitHub API/SwiftUI-Combine-Example/FoundationExtensions.swift

@@ -1,34 +1,57 @@
 import SwiftUI
 import Combine
 
-enum RequestError: Error {
+enum URLSessionError: Error {
-    case request(code: Int, error: Error?)
+    case invalidResponse
-    case unknown
+    case serverErrorMessage(statusCode: Int, data: Data)
+    case urlError(URLError)
 }
 
 extension URLSession {
-    func send(request: URLRequest) -> AnyPublisher<(data: Data, response: HTTPURLResponse), RequestError> {
+    func send(request: URLRequest) -> AnyPublisher<Data, URLSessionError> {
-        AnyPublisher<(data: Data, response: HTTPURLResponse), RequestError> { subscriber in
-            let task = self.dataTask(with: request) { data, response, error in
-                DispatchQueue.main.async {
-                    let httpReponse = response as? HTTPURLResponse
-                    if let data = data, let httpReponse = httpReponse, 200..<300 ~= httpReponse.statusCode {
-                        _ = subscriber.receive((data, httpReponse))
-                        subscriber.receive(completion: .finished)
-                    }
-                    else if let httpReponse = httpReponse {
-                        subscriber.receive(completion: .failure(.request(code: httpReponse.statusCode, error: error)))
-                    }
-                    else {
-                        subscriber.receive(completion: .failure(.unknown))
-                    }
-                }
-            }
 
-            subscriber.receive(subscription: AnySubscription(task.cancel))
+        dataTaskPublisher(for: request)
-            task.resume()
+            .mapError { URLSessionError.urlError($0) }
-        }
+            .flatMap { data, response -> AnyPublisher<Data, URLSessionError> in
+                guard let response = response as? HTTPURLResponse else {
+                    return .fail(.invalidResponse)
+                }
+
+                guard 200..<300 ~= response.statusCode else {
+                    return .fail(.serverErrorMessage(statusCode: response.statusCode,
+                                                     data: data))
+                }
+
+                return .just(data)
+        }.eraseToAnyPublisher()
     }
 }
 
 extension JSONDecoder: TopLevelDecoder {}
+
+extension Publisher {
+
+    /// - seealso: https://twitter.com/peres/status/1136132104020881408
+    func flatMapLatest<T: Publisher>(_ transform: @escaping (Self.Output) -> T) -> Publishers.SwitchToLatest<T, Publishers.Map<Self, T>> where T.Failure == Self.Failure {
+        map(transform).switchToLatest()
+    }
+}
+
+extension Publisher {
+
+    static func empty() -> AnyPublisher<Output, Failure> {
+        return Publishers.Empty()
+            .eraseToAnyPublisher()
+    }
+
+    static func just(_ output: Output) -> AnyPublisher<Output, Failure> {
+        return Just(output)
+            .catch { _ in AnyPublisher<Output, Failure>.empty() }
+            .eraseToAnyPublisher()
+    }
+
+    static func fail(_ error: Failure) -> AnyPublisher<Output, Failure> {
+        return Publishers.Fail(error: error)
+            .eraseToAnyPublisher()
+    }
+}

Other Projects/Combine using GitHub API/SwiftUI-Combine-Example/SceneDelegate.swift

@@ -11,5 +11,11 @@ final class SceneDelegate: UIResponder, UIWindowSceneDelegate {
         )
         self.window = window
         window.makeKeyAndVisible()
+        if let windowScene = scene as? UIWindowScene {
+            let window = UIWindow(windowScene: windowScene)
+            window.rootViewController = UIHostingController(rootView: SearchUserView().environmentObject(SearchUserViewModel()))
+            self.window = window
+            window.makeKeyAndVisible()
+        }
     }
 }

Other Projects/Combine using GitHub API/SwiftUI-Combine-Example/SearchUserViewModel.swift

@@ -36,10 +36,10 @@ final class SearchUserViewModel: BindableObject {
         cancellable = assign
 
         URLSession.shared.send(request: request)
-            .map { $0.data }
             .decode(type: SearchUserResponse.self, decoder: JSONDecoder())
             .map { $0.items }
             .replaceError(with: [])
+            .receive(on: DispatchQueue.main)
             .receive(subscriber: assign)
     }
 
@@ -50,10 +50,11 @@ final class SearchUserViewModel: BindableObject {
 
         let request = URLRequest(url: user.avatar_url)
         URLSession.shared.send(request: request)
-            .map { UIImage(data: $0.data) }
+            .map { UIImage(data: $0) }
             .replaceError(with: nil)
             .eraseToAnyPublisher()
-            .receive(subscriber: Subscribers.Sink<AnyPublisher<UIImage?, Never>> { [weak self] image in
+            .receive(on: DispatchQueue.main)
+            .receive(subscriber: Subscribers.Sink<UIImage?, Never> { [weak self] image in
                 self?.userImages[user] = image
             })
     }

Other Projects/GitHub Search/GitHubSearchWithSwiftUI.xcodeproj/project.pbxproj

@@ -7,6 +7,10 @@
 	objects = {
 
 /* Begin PBXBuildFile section */
+		BB3DC0CE22D54717006F0587 /* AnySubscription.swift in Sources */ = {isa = PBXBuildFile; fileRef = BB3DC0CD22D54717006F0587 /* AnySubscription.swift */; };
+		BB3DC0D022D54737006F0587 /* ErrorResponse.swift in Sources */ = {isa = PBXBuildFile; fileRef = BB3DC0CF22D54737006F0587 /* ErrorResponse.swift */; };
+		BB3DC0D222D54826006F0587 /* WebView.swift in Sources */ = {isa = PBXBuildFile; fileRef = BB3DC0D122D54826006F0587 /* WebView.swift */; };
+		BB3DC0D422D54927006F0587 /* Publisher.Extension.swift in Sources */ = {isa = PBXBuildFile; fileRef = BB3DC0D322D54927006F0587 /* Publisher.Extension.swift */; };
 		ED73146222A6F228004F8DA0 /* RepositoryListView.swift in Sources */ = {isa = PBXBuildFile; fileRef = ED73146122A6F228004F8DA0 /* RepositoryListView.swift */; };
 		EDDADAB122A808D500FEDC01 /* Combine.swift in Sources */ = {isa = PBXBuildFile; fileRef = EDDADAB022A808D500FEDC01 /* Combine.swift */; };
 		EDDADAB322A809E600FEDC01 /* URLSession.Combine.swift in Sources */ = {isa = PBXBuildFile; fileRef = EDDADAB222A809E600FEDC01 /* URLSession.Combine.swift */; };
@@ -24,6 +28,10 @@
 /* End PBXBuildFile section */
 
 /* Begin PBXFileReference section */
+		BB3DC0CD22D54717006F0587 /* AnySubscription.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AnySubscription.swift; sourceTree = "<group>"; };
+		BB3DC0CF22D54737006F0587 /* ErrorResponse.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ErrorResponse.swift; sourceTree = "<group>"; };
+		BB3DC0D122D54826006F0587 /* WebView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = WebView.swift; sourceTree = "<group>"; };
+		BB3DC0D322D54927006F0587 /* Publisher.Extension.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Publisher.Extension.swift; sourceTree = "<group>"; };
 		ED73146122A6F228004F8DA0 /* RepositoryListView.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = RepositoryListView.swift; sourceTree = "<group>"; };
 		EDDADAB022A808D500FEDC01 /* Combine.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Combine.swift; sourceTree = "<group>"; };
 		EDDADAB222A809E600FEDC01 /* URLSession.Combine.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = URLSession.Combine.swift; sourceTree = "<group>"; };
@@ -59,6 +67,7 @@
 				EDDADAB022A808D500FEDC01 /* Combine.swift */,
 				EDDADAB222A809E600FEDC01 /* URLSession.Combine.swift */,
 				EDDADABA22A82C2500FEDC01 /* JSONDecoder.Extension.swift */,
+				BB3DC0D322D54927006F0587 /* Publisher.Extension.swift */,
 			);
 			path = Extension;
 			sourceTree = "<group>";
@@ -109,6 +118,7 @@
 				ED73146122A6F228004F8DA0 /* RepositoryListView.swift */,
 				EDDF06B622A6CD8300B23D44 /* RepositoryView.swift */,
 				EDDADAB822A82C0400FEDC01 /* RepositoryListViewModel.swift */,
+				BB3DC0D122D54826006F0587 /* WebView.swift */,
 			);
 			path = View;
 			sourceTree = "<group>";
@@ -119,6 +129,8 @@
 				EDDF06B922A6D78200B23D44 /* Repository.swift */,
 				EDDADAB422A821CD00FEDC01 /* ItemResponse.swift */,
 				EDDADAB622A829A300FEDC01 /* RepositoryAPI.swift */,
+				BB3DC0CD22D54717006F0587 /* AnySubscription.swift */,
+				BB3DC0CF22D54737006F0587 /* ErrorResponse.swift */,
 			);
 			path = Model;
 			sourceTree = "<group>";
@@ -195,8 +207,10 @@
 			buildActionMask = 2147483647;
 			files = (
 				ED73146222A6F228004F8DA0 /* RepositoryListView.swift in Sources */,
+				BB3DC0CE22D54717006F0587 /* AnySubscription.swift in Sources */,
 				EDDADAB722A829A300FEDC01 /* RepositoryAPI.swift in Sources */,
 				EDDF06A222A6C61C00B23D44 /* AppDelegate.swift in Sources */,
+				BB3DC0D422D54927006F0587 /* Publisher.Extension.swift in Sources */,
 				EDDADAB522A821CD00FEDC01 /* ItemResponse.swift in Sources */,
 				EDDF06A422A6C61C00B23D44 /* SceneDelegate.swift in Sources */,
 				EDDADAB922A82C0400FEDC01 /* RepositoryListViewModel.swift in Sources */,
@@ -205,6 +219,8 @@
 				EDDADAB322A809E600FEDC01 /* URLSession.Combine.swift in Sources */,
 				EDDADABB22A82C2500FEDC01 /* JSONDecoder.Extension.swift in Sources */,
 				EDDADAB122A808D500FEDC01 /* Combine.swift in Sources */,
+				BB3DC0D022D54737006F0587 /* ErrorResponse.swift in Sources */,
+				BB3DC0D222D54826006F0587 /* WebView.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};

Other Projects/GitHub Search/GitHubSearchWithSwiftUI/Extension/Publisher.Extension.swift

@@ -0,0 +1,36 @@
+//
+//  Publisher.Extension.swift
+//  GitHubSearchWithSwiftUI
+//
+//  Created by John Holdsworth on 09/07/2019.
+//  Copyright © 2019 jp.marty-suzuki. All rights reserved.
+//
+
+import Combine
+
+extension Publisher {
+
+    /// - seealso: https://twitter.com/peres/status/1136132104020881408
+    func flatMapLatest<T: Publisher>(_ transform: @escaping (Self.Output) -> T) -> Publishers.SwitchToLatest<T, Publishers.Map<Self, T>> where T.Failure == Self.Failure {
+        map(transform).switchToLatest()
+    }
+}
+
+extension Publisher {
+
+    static func empty() -> AnyPublisher<Output, Failure> {
+        return Publishers.Empty()
+            .eraseToAnyPublisher()
+    }
+
+    static func just(_ output: Output) -> AnyPublisher<Output, Failure> {
+        return Just(output)
+            .catch { _ in AnyPublisher<Output, Failure>.empty() }
+            .eraseToAnyPublisher()
+    }
+
+    static func fail(_ error: Failure) -> AnyPublisher<Output, Failure> {
+        return Publishers.Fail(error: error)
+            .eraseToAnyPublisher()
+    }
+}

Other Projects/GitHub Search/GitHubSearchWithSwiftUI/Extension/URLSession.Combine.swift

@@ -15,44 +15,26 @@ extension CombineExtension where Base == URLSession {
 
     func send(request: URLRequest) -> AnyPublisher<Data, URLSessionError> {
 
-        AnyPublisher<Data, URLSessionError> { [base] subscriber in
+        base.dataTaskPublisher(for: request)
-
+            .mapError { URLSessionError.urlError($0) }
-            let task = base.dataTask(with: request) { data, response, error in
+            .flatMap { data, response -> AnyPublisher<Data, URLSessionError> in
-
                 guard let response = response as? HTTPURLResponse else {
-                    subscriber.receive(completion: .failure(.invalidResponse))
+                    return .fail(.invalidResponse)
-                    return
                 }
 
                 guard 200..<300 ~= response.statusCode else {
-                    let e = URLSessionError.serverError(statusCode: response.statusCode,
+                    return .fail(.serverErrorMessage(statusCode: response.statusCode,
-                                                        error: error)
+                                                     data: data))
-                    subscriber.receive(completion: .failure(e))
-                    return
                 }
 
-                guard let data = data else {
+                return .just(data)
-                    subscriber.receive(completion: .failure(.noData))
-                    return
-                }
-
-                if let error = error {
-                    subscriber.receive(completion: .failure(.unknown(error)))
-                } else {
-                    _ = subscriber.receive(data)
-                    subscriber.receive(completion: .finished)
-                }
             }
-
+            .eraseToAnyPublisher()
-            // TODO: cancel task when subscriber cancelled
-            task.resume()
-        }
     }
 }
 
 enum URLSessionError: Error {
     case invalidResponse
-    case noData
+    case serverErrorMessage(statusCode: Int, data: Data)
-    case serverError(statusCode: Int, error: Error?)
+    case urlError(URLError)
-    case unknown(Error)
 }

Other Projects/GitHub Search/GitHubSearchWithSwiftUI/Model/AnySubscription.swift

@@ -0,0 +1,25 @@
+//
+//  AnySubscription.swift
+//  GitHubSearchWithSwiftUI
+//
+//  Created by John Holdsworth on 09/07/2019.
+//  Copyright © 2019 jp.marty-suzuki. All rights reserved.
+//
+
+import Combine
+
+/// - seealso: https://twitter.com/peres/status/1135970931153821696
+final class AnySubscription: Subscription {
+
+    private let cancellable: AnyCancellable
+
+    init(_ cancel: @escaping () -> Void) {
+        self.cancellable = AnyCancellable(cancel)
+    }
+
+    func request(_ demand: Subscribers.Demand) {}
+
+    func cancel() {
+        cancellable.cancel()
+    }
+}

Other Projects/GitHub Search/GitHubSearchWithSwiftUI/Model/ErrorResponse.swift

@@ -0,0 +1,13 @@
+//
+//  ErrorResponse.swift
+//  GitHubSearchWithSwiftUI
+//
+//  Created by John Holdsworth on 09/07/2019.
+//  Copyright © 2019 jp.marty-suzuki. All rights reserved.
+//
+
+import Foundation
+
+struct ErrorResponse: Decodable, Error {
+    let message: String
+}

Other Projects/GitHub Search/GitHubSearchWithSwiftUI/Model/RepositoryAPI.swift

@@ -10,27 +10,42 @@ import Combine
 import Foundation
 
 enum RepositoryAPI {
+    typealias SearchResponse = AnyPublisher<Result<[Repository], ErrorResponse>, Never>
+    typealias SendRequest = (URLRequest) -> AnyPublisher<Data, URLSessionError>
 
-    static func search(query: String) -> AnyPublisher<[Repository], Error> {
+    static func search(query: String) -> SearchResponse {
+        search(query: query, sendRequest: URLSession.shared.combine.send)
+    }
+
+    static func search(query: String, sendRequest: SendRequest) -> SearchResponse {
 
         guard var components = URLComponents(string: "https://api.github.com/search/repositories") else {
-            return Publishers.Empty<[Repository], Error>().eraseToAnyPublisher()
+            return .empty()
         }
         components.queryItems = [URLQueryItem(name: "q", value: query)]
 
         guard let url = components.url else {
-            return Publishers.Empty<[Repository], Error>().eraseToAnyPublisher()
+            return .empty()
         }
 
         var request = URLRequest(url: url)
         request.addValue("application/json", forHTTPHeaderField: "Content-Type")
         let decoder = JSONDecoder()
         decoder.keyDecodingStrategy = .convertFromSnakeCase
-        return URLSession.shared.combine.send(request: request)
+        return sendRequest(request)
             .decode(type: ItemResponse<Repository>.self, decoder: decoder)
-            .map { $0.items }
+            .map { Result<[Repository], ErrorResponse>.success($0.items) }
-            .handleEvents(receiveOutput: { print($0) },
+            .catch { error -> SearchResponse in
-                          receiveCompletion: { print($0)})
+                guard case let .serverErrorMessage(_, data)? = error as? URLSessionError else {
+                    return .just(.success([]))
+                }
+                do {
+                    let response = try JSONDecoder().decode(ErrorResponse.self, from: data)
+                    return .just(.failure(response))
+                } catch _ {
+                    return .just(.success([]))
+                }
+            }
             .eraseToAnyPublisher()
     }
 }

Other Projects/GitHub Search/GitHubSearchWithSwiftUI/SceneDelegate.swift

@@ -20,12 +20,12 @@ class SceneDelegate: UIResponder, UIWindowSceneDelegate {
         // This delegate does not imply the connecting scene or session are new (see `application:configurationForConnectingSceneSession` instead).
 
         // Use a UIHostingController as window root view controller
-        let window = UIWindow(frame: UIScreen.main.bounds)
+        if let windowScene = scene as? UIWindowScene {
-        window.rootViewController = UIHostingController(rootView:
+            let window = UIWindow(windowScene: windowScene)
-            RepositoryListView().environmentObject(RepositoryListViewModel())
+            window.rootViewController = UIHostingController(rootView: RepositoryListView(viewModel: RepositoryListViewModel(mainScheduler: DispatchQueue.main)))
-        )
+            self.window = window
-        self.window = window
+            window.makeKeyAndVisible()
-        window.makeKeyAndVisible()
+        }
     }
 
     func sceneDidDisconnect(_ scene: UIScene) {

Other Projects/GitHub Search/GitHubSearchWithSwiftUI/View/RepositoryListView.swift

@@ -10,27 +10,51 @@ import SwiftUI
 
 struct RepositoryListView : View {
 
-    @EnvironmentObject private var viewModel: RepositoryListViewModel
+    @ObjectBinding
-    @State private var text: String = ""
+    private(set) var viewModel: RepositoryListViewModel
 
     var body: some View {
 
         NavigationView {
 
-            TextField($text,
+            VStack {
-                      placeholder: Text("Search reposipories..."),
+            HStack {
-                      onCommit: { self.viewModel.search(query: self.text) })
+
+                TextField($viewModel.text,
+                          placeholder: Text("Search reposipories..."),
+                          onCommit: { self.viewModel.search() })
+                    .frame(height: 40)
+                    .padding(EdgeInsets(top: 0, leading: 8, bottom: 0, trailing: 8))
+                    .border(Color.gray, cornerRadius: 8)
+                    .padding(EdgeInsets(top: 0, leading: 16, bottom: 0, trailing: 16))
+
+                Button(action: { self.viewModel.search() }) {
+                    Text("Search")
+                }
                 .frame(height: 40)
                 .padding(EdgeInsets(top: 0, leading: 8, bottom: 0, trailing: 8))
-                .border(Color.gray, cornerRadius: 8)
+                .border(Color.blue, cornerRadius: 8)
-                .padding(EdgeInsets(top: 0, leading: 16, bottom: 0, trailing: 16))
+                .padding(EdgeInsets(top: 0, leading: 0, bottom: 0, trailing: 16))
+            }
 
             List {
 
+                viewModel.errorMessage.map(Text.init)?
+                    .lineLimit(nil)
+                    .multilineTextAlignment(.center)
+
                 ForEach(viewModel.repositories.identified(by: \.id)) { repository in
-                     RepositoryView(repository: repository)
+
+                    NavigationLink(destination:
+                        WebView(url: repository.htmlUrl)
+                            .navigationBarTitle(Text(repository.fullName))
+                    ) {
+
+                        RepositoryView(repository: repository)
+                    }
                 }
             }
+            }
             .navigationBarTitle(Text("Search🔍"))
         }
     }

Other Projects/GitHub Search/GitHubSearchWithSwiftUI/View/RepositoryListViewModel.swift

@@ -11,39 +11,60 @@ import Foundation
 import SwiftUI
 
 final class RepositoryListViewModel: BindableObject {
+    typealias SearchRepositories = (String) -> AnyPublisher<Result<[Repository], ErrorResponse>, Never>
 
     let didChange: AnyPublisher<RepositoryListViewModel, Never>
     private let _didChange = PassthroughSubject<RepositoryListViewModel, Never>()
 
     private let _searchWithQuery = PassthroughSubject<String, Never>()
-    private lazy var repositoriesAssign = Subscribers.Assign(object: self, keyPath: \.repositories)
+    private var cancellables: [AnyCancellable] = []
 
     private(set) var repositories: [Repository] = [] {
         didSet {
-            // TODO: Do not want to use DispatchQueue.main here
+            _didChange.send(self)
-            DispatchQueue.main.async {
-                self._didChange.send(self)
-            }
         }
     }
-
+    private(set) var errorMessage: String? {
-    deinit {
+        didSet {
-        repositoriesAssign.cancel()
+            _didChange.send(self)
+        }
     }
+    var text: String = ""
+
+    init<S: Scheduler>(searchRepositories: @escaping SearchRepositories = RepositoryAPI.search,
+                       mainScheduler: S) {
 
-    init() {
         self.didChange = _didChange.eraseToAnyPublisher()
 
-        _searchWithQuery
+        let response = _searchWithQuery
-            .flatMap { query -> AnyPublisher<[Repository], Never> in
+            .filter { !$0.isEmpty }
-                RepositoryAPI.search(query: query)
+            .debounce(for: .milliseconds(300), scheduler: mainScheduler)
-                    .replaceError(with: [])
+            .flatMapLatest { query -> AnyPublisher<([Repository], String?), Never> in
+                searchRepositories(query)
+                    .map { result -> ([Repository], String?) in
+                        switch result {
+                        case let .success(repositories):
+                            return (repositories, nil)
+                        case let .failure(response):
+                            return ([], response.message)
+                        }
+                    }
                     .eraseToAnyPublisher()
             }
-            .receive(subscriber: repositoriesAssign)
+            .receive(on: mainScheduler)
+            .share()
+
+        cancellables += [
+            response
+                .map { $0.0 }
+                .assign(to: \.repositories, on: self),
+            response
+                .map { $0.1 }
+                .assign(to: \.errorMessage, on: self)
+        ]
     }
 
-    func search(query: String) {
+    func search() {
-        _searchWithQuery.send(query)
+        _searchWithQuery.send(text)
     }
 }

Other Projects/GitHub Search/GitHubSearchWithSwiftUI/View/WebView.swift

@@ -0,0 +1,21 @@
+//
+//  WebView.swift
+//  GitHubSearchWithSwiftUI
+//
+//  Created by marty-suzuki on 2019/06/11.
+//  Copyright © 2019 jp.marty-suzuki. All rights reserved.
+//
+
+import SafariServices
+import SwiftUI
+
+struct WebView: UIViewControllerRepresentable {
+
+    let url: URL
+
+    func makeUIViewController(context: UIViewControllerRepresentableContext<WebView>) -> SFSafariViewController {
+        return SFSafariViewController(url: url)
+    }
+
+    func updateUIViewController(_ uiViewController: SFSafariViewController, context: UIViewControllerRepresentableContext<WebView>) {}
+}