Refactoring

MastodonAPI/Sources/MastodonAPI/MastodonAPIClient.swift

@@ -6,10 +6,11 @@ import HTTP
 import Mastodon
 
 public final class MastodonAPIClient: HTTPClient {
-    public var instanceURL: URL?
+    public var instanceURL: URL
     public var accessToken: String?
 
-    public required init(session: Session) {
+    public required init(session: Session, instanceURL: URL) {
+        self.instanceURL = instanceURL
         super.init(session: session, decoder: MastodonDecoder())
     }
 
@@ -20,11 +21,7 @@ public final class MastodonAPIClient: HTTPClient {
 
 extension MastodonAPIClient {
     public func request<E: Endpoint>(_ endpoint: E) -> AnyPublisher<E.ResultType, Error> {
-        guard let instanceURL = instanceURL else {
+        super.request(
-            return Fail(error: URLError(.badURL)).eraseToAnyPublisher()
-        }
-
-        return super.request(
             MastodonAPITarget(baseURL: instanceURL, endpoint: endpoint, accessToken: accessToken),
             decodeErrorsAs: APIError.self)
     }

ServiceLayer/Sources/ServiceLayer/Services/AllIdentitiesService.swift

@@ -36,29 +36,25 @@ public extension AllIdentitiesService {
         database.createIdentity(id: id, url: instanceURL)
     }
 
-    func authorizeIdentity(id: UUID, instanceURL: URL) -> AnyPublisher<Never, Error> {
+    func authorizeAndCreateIdentity(id: UUID, url: URL) -> AnyPublisher<Never, Error> {
+        AuthenticationService(url: url, environment: environment)
+            .authenticate()
+            .tryMap {
                 let secrets = Secrets(identityID: id, keychain: environment.keychain)
-        let authenticationService = AuthenticationService(environment: environment)
 
-        return authenticationService.authorizeApp(instanceURL: instanceURL)
+                try secrets.setInstanceURL(url)
-            .tryMap { appAuthorization -> (URL, AppAuthorization) in
+                try secrets.setClientID($0.clientId)
-                try secrets.setInstanceURL(instanceURL)
+                try secrets.setClientSecret($0.clientSecret)
-                try secrets.setClientID(appAuthorization.clientId)
+                try secrets.setAccessToken($1.accessToken)
-                try secrets.setClientSecret(appAuthorization.clientSecret)
-
-                return (instanceURL, appAuthorization)
             }
-            .flatMap(authenticationService.authenticate(instanceURL:appAuthorization:))
+            .flatMap { database.createIdentity(id: id, url: url) }
-            .tryMap { try secrets.setAccessToken($0.accessToken) }
             .ignoreOutput()
             .eraseToAnyPublisher()
     }
 
     func deleteIdentity(_ identity: Identity) -> AnyPublisher<Never, Error> {
         let secrets = Secrets(identityID: identity.id, keychain: environment.keychain)
-        let mastodonAPIClient = MastodonAPIClient(session: environment.session)
+        let mastodonAPIClient = MastodonAPIClient(session: environment.session, instanceURL: identity.url)
-
-        mastodonAPIClient.instanceURL = identity.url
 
         return database.deleteIdentity(id: identity.id)
             .collect()

ServiceLayer/Sources/ServiceLayer/Services/AuthenticationService.swift

@@ -5,69 +5,33 @@ import Foundation
 import Mastodon
 import MastodonAPI
 
-public struct AuthenticationService {
+public enum AuthenticationError: Error {
+    case canceled
+}
+
+struct AuthenticationService {
     private let mastodonAPIClient: MastodonAPIClient
     private let webAuthSessionType: WebAuthSession.Type
     private let webAuthSessionContextProvider = WebAuthSessionContextProvider()
 
-    public init(environment: AppEnvironment) {
+    init(url: URL, environment: AppEnvironment) {
-        mastodonAPIClient = MastodonAPIClient(session: environment.session)
+        mastodonAPIClient = MastodonAPIClient(session: environment.session, instanceURL: url)
         webAuthSessionType = environment.webAuthSessionType
     }
 }
 
-public extension AuthenticationService {
+extension AuthenticationService {
-    func authorizeApp(instanceURL: URL) -> AnyPublisher<AppAuthorization, Error> {
+    func authenticate() -> AnyPublisher<(AppAuthorization, AccessToken), Error> {
-        let endpoint = AppAuthorizationEndpoint.apps(
+        let appAuthorization = mastodonAPIClient.request(
+            AppAuthorizationEndpoint.apps(
                 clientName: OAuth.clientName,
                 redirectURI: OAuth.callbackURL.absoluteString,
                 scopes: OAuth.scopes,
-            website: OAuth.website)
+                website: OAuth.website))
-        let target = MastodonAPITarget(baseURL: instanceURL, endpoint: endpoint, accessToken: nil)
+            .share()
 
-        return mastodonAPIClient.request(target)
+        return appAuthorization
-    }
+            .zip(appAuthorization.flatMap(authenticate(appAuthorization:)))
-
-    func authenticate(instanceURL: URL, appAuthorization: AppAuthorization) -> AnyPublisher<AccessToken, Error> {
-        guard let authorizationURL = authorizationURL(
-                instanceURL: instanceURL,
-                clientID: appAuthorization.clientId) else {
-            return Fail(error: URLError(.badURL)).eraseToAnyPublisher()
-        }
-
-        return webAuthSessionType.publisher(
-            url: authorizationURL,
-            callbackURLScheme: OAuth.callbackURLScheme,
-            presentationContextProvider: webAuthSessionContextProvider)
-            .tryCatch { error -> AnyPublisher<URL?, Error> in
-                if (error as? WebAuthSessionError)?.code == .canceledLogin {
-                    return Just(nil).setFailureType(to: Error.self).eraseToAnyPublisher()
-                }
-
-                throw error
-            }
-            .compactMap { $0 }
-            .tryMap { url -> String in
-                guard let queryItems = URLComponents(url: url, resolvingAgainstBaseURL: true)?.queryItems,
-                      let code = queryItems.first(where: {
-                        $0.name == OAuth.codeCallbackQueryItemName
-                      })?.value
-                else { throw OAuthError.codeNotFound }
-
-                return code
-            }
-            .flatMap { code -> AnyPublisher<AccessToken, Error> in
-                let endpoint = AccessTokenEndpoint.oauthToken(
-                    clientID: appAuthorization.clientId,
-                    clientSecret: appAuthorization.clientSecret,
-                    code: code,
-                    grantType: OAuth.grantType,
-                    scopes: OAuth.scopes,
-                    redirectURI: OAuth.callbackURL.absoluteString)
-                let target = MastodonAPITarget(baseURL: instanceURL, endpoint: endpoint, accessToken: nil)
-
-                return mastodonAPIClient.request(target)
-            }
             .eraseToAnyPublisher()
     }
 }
@@ -87,19 +51,66 @@ private extension AuthenticationService {
         case codeNotFound
     }
 
-    func authorizationURL(instanceURL: URL, clientID: String) -> URL? {
+    static func extractCode(oauthCallbackURL: URL) throws -> String {
-        guard var authorizationURLComponents = URLComponents(url: instanceURL, resolvingAgainstBaseURL: true) else {
+        guard let queryItems = URLComponents(
-            return nil
+                url: oauthCallbackURL,
+                resolvingAgainstBaseURL: true)?.queryItems,
+              let code = queryItems.first(where: {
+                $0.name == OAuth.codeCallbackQueryItemName
+              })?.value
+        else { throw OAuthError.codeNotFound }
+
+        return code
     }
 
+    func authorizationURL(appAuthorization: AppAuthorization) throws -> URL {
+        guard var authorizationURLComponents = URLComponents(
+                url: mastodonAPIClient.instanceURL,
+                resolvingAgainstBaseURL: true)
+        else { throw URLError(.badURL) }
+
         authorizationURLComponents.path = "/oauth/authorize"
         authorizationURLComponents.queryItems = [
-            "client_id": clientID,
+            .init(name: "client_id", value: appAuthorization.clientId),
-            "scope": OAuth.scopes,
+            .init(name: "scope", value: OAuth.scopes),
-            "response_type": "code",
+            .init(name: "response_type", value: "code"),
-            "redirect_uri": OAuth.callbackURL.absoluteString
+            .init(name: "redirect_uri", value: OAuth.callbackURL.absoluteString)
-        ].map { URLQueryItem(name: $0, value: $1) }
+        ]
 
-        return authorizationURLComponents.url
+        guard let authorizationURL = authorizationURLComponents.url else {
+            throw URLError(.badURL)
+        }
+
+        return authorizationURL
+    }
+
+    func authenticate(appAuthorization: AppAuthorization) -> AnyPublisher<AccessToken, Error> {
+        Just(appAuthorization)
+            .tryMap(authorizationURL(appAuthorization:))
+            .flatMap {
+                webAuthSessionType.publisher(
+                    url: $0,
+                    callbackURLScheme: OAuth.callbackURLScheme,
+                    presentationContextProvider: webAuthSessionContextProvider)
+            }
+            .mapError { error -> Error in
+                if (error as? WebAuthSessionError)?.code == .canceledLogin {
+                    return AuthenticationError.canceled as Error
+                }
+
+                return error
+            }
+            .tryMap(Self.extractCode(oauthCallbackURL:))
+            .flatMap {
+                mastodonAPIClient.request(
+                    AccessTokenEndpoint.oauthToken(
+                        clientID: appAuthorization.clientId,
+                        clientSecret: appAuthorization.clientSecret,
+                        code: $0,
+                        grantType: OAuth.grantType,
+                        scopes: OAuth.scopes,
+                        redirectURI: OAuth.callbackURL.absoluteString))
+            }
+            .eraseToAnyPublisher()
     }
 }

ServiceLayer/Sources/ServiceLayer/Services/IdentityService.swift

@@ -24,8 +24,8 @@ public struct IdentityService {
         secrets = Secrets(
             identityID: id,
             keychain: environment.keychain)
-        mastodonAPIClient = MastodonAPIClient(session: environment.session)
+        mastodonAPIClient = MastodonAPIClient(session: environment.session,
-        mastodonAPIClient.instanceURL = try secrets.getInstanceURL()
+                                              instanceURL: try secrets.getInstanceURL())
         mastodonAPIClient.accessToken = try? secrets.getAccessToken()
 
         contentDatabase = try ContentDatabase(identityID: id,

ServiceLayer/Sources/ServiceLayer/Utilities/WebAuthSession.swift

@@ -16,8 +16,8 @@ extension WebAuthSession {
     static func publisher(
         url: URL,
         callbackURLScheme: String?,
-        presentationContextProvider: WebAuthPresentationContextProviding) -> AnyPublisher<URL?, Error> {
+        presentationContextProvider: WebAuthPresentationContextProviding) -> AnyPublisher<URL, Error> {
-        Future<URL?, Error> { promise in
+        Future<URL, Error> { promise in
             let webAuthSession = Self(
                 url: url,
                 callbackURLScheme: callbackURLScheme) { oauthCallbackURL, error in
@@ -25,6 +25,10 @@ extension WebAuthSession {
                     return promise(.failure(error))
                 }
 
+                guard let oauthCallbackURL = oauthCallbackURL else {
+                    return promise(.failure(URLError(.unknown)))
+                }
+
                 return promise(.success(oauthCallbackURL))
             }
 

ServiceLayer/Sources/ServiceLayerMocks/MockAppEnvironment.swift

@@ -18,11 +18,11 @@ public extension AppEnvironment {
                      fixtureDatabase: IdentityDatabase? = nil) -> Self {
         AppEnvironment(
             session: Session(configuration: .stubbing),
-            webAuthSessionType: SuccessfulMockWebAuthSession.self,
+            webAuthSessionType: webAuthSessionType,
-            keychain: MockKeychain.self,
+            keychain: keychain,
-            userDefaults: MockUserDefaults(),
+            userDefaults: userDefaults,
-            userNotificationClient: .mock,
+            userNotificationClient: userNotificationClient,
-            inMemoryContent: true,
+            inMemoryContent: inMemoryContent,
             fixtureDatabase: fixtureDatabase)
     }
 }

ServiceLayer/Tests/ServiceLayerTests/AuthenticationServiceTests.swift

@@ -8,20 +8,12 @@ import XCTest
 
 class AuthenticationServiceTests: XCTestCase {
     func testAuthentication() throws {
-        let sut = AuthenticationService(environment: .mock())
+        let sut = AuthenticationService(url: URL(string: "https://mastodon.social")!, environment: .mock())
-        let instanceURL = URL(string: "https://mastodon.social")!
+        let authenticationRecorder = sut.authenticate().record()
-        let appAuthorizationRecorder = sut.authorizeApp(instanceURL: instanceURL).record()
+        let (appAuthorization, accessToken) = try wait(for: authenticationRecorder.next(), timeout: 1)
-        let appAuthorization = try wait(for: appAuthorizationRecorder.next(), timeout: 1)
 
         XCTAssertEqual(appAuthorization.clientId, "AUTHORIZATION_CLIENT_ID_STUB_VALUE")
         XCTAssertEqual(appAuthorization.clientSecret, "AUTHORIZATION_CLIENT_SECRET_STUB_VALUE")
-
-        let accessTokenRecorder = sut.authenticate(
-            instanceURL: instanceURL,
-            appAuthorization: appAuthorization)
-            .record()
-        let accessToken = try wait(for: accessTokenRecorder.next(), timeout: 1)
-
         XCTAssertEqual(accessToken.accessToken, "ACCESS_TOKEN_STUB_VALUE")
     }
 }

ViewModels/Sources/ViewModels/AddIdentityViewModel.swift

@@ -11,12 +11,12 @@ public final class AddIdentityViewModel: ObservableObject {
     public let addedIdentityID: AnyPublisher<UUID, Never>
 
     private let allIdentitiesService: AllIdentitiesService
-    private let addedIdentityIDInput = PassthroughSubject<UUID, Never>()
+    private let addedIdentityIDSubject = PassthroughSubject<UUID, Never>()
     private var cancellables = Set<AnyCancellable>()
 
     init(allIdentitiesService: AllIdentitiesService) {
         self.allIdentitiesService = allIdentitiesService
-        addedIdentityID = addedIdentityIDInput.eraseToAnyPublisher()
+        addedIdentityID = addedIdentityIDSubject.eraseToAnyPublisher()
     }
 }
 
@@ -33,22 +33,26 @@ public extension AddIdentityViewModel {
             return
         }
 
-        allIdentitiesService.authorizeIdentity(id: identityID, instanceURL: instanceURL)
+        allIdentitiesService.authorizeAndCreateIdentity(id: identityID, url: instanceURL)
-            .collect()
-            .map { _ in (identityID, instanceURL) }
-            .flatMap(allIdentitiesService.createIdentity(id:instanceURL:))
-            .mapError {
-                return $0
-            }
             .receive(on: DispatchQueue.main)
-            .assignErrorsToAlertItem(to: \.alertItem, on: self)
+            .catch { [weak self] error -> Empty<Never, Never> in
-            .handleEvents(
+                if case AuthenticationError.canceled = error {
-                receiveSubscription: { [weak self] _ in self?.loading = true },
+                    // no-op
-                receiveCompletion: { [weak self] _ in self?.loading = false  })
+                } else {
-            .sink { [weak self] in
+                    self?.alertItem = AlertItem(error: error)
-                guard let self = self, case .finished = $0 else { return }
+                }
 
-                self.addedIdentityIDInput.send(identityID)
+                return Empty()
+            }
+            .handleEvents(receiveSubscription: { [weak self] _ in self?.loading = true })
+            .sink { [weak self] in
+                guard let self = self else { return }
+
+                self.loading = false
+
+                if case .finished = $0 {
+                    self.addedIdentityIDSubject.send(identityID)
+                }
             } receiveValue: { _ in }
             .store(in: &cancellables)
     }
@@ -71,7 +75,7 @@ public extension AddIdentityViewModel {
             .sink { [weak self] in
                 guard let self = self, case .finished = $0 else { return }
 
-                self.addedIdentityIDInput.send(identityID)
+                self.addedIdentityIDSubject.send(identityID)
             } receiveValue: { _ in }
             .store(in: &cancellables)
     }

ViewModels/Sources/ViewModels/Extensions/Publisher+Extensions.swift

@@ -8,8 +8,10 @@ extension Publisher {
         to keyPath: ReferenceWritableKeyPath<Root, AlertItem?>,
         on object: Root) -> AnyPublisher<Output, Never> {
         self.catch { [weak object] error -> Empty<Output, Never> in
+            if let object = object {
                 DispatchQueue.main.async {
-                object?[keyPath: keyPath] = AlertItem(error: error)
+                    object[keyPath: keyPath] = AlertItem(error: error)
+                }
             }
 
             return Empty()