Refactor WriteFreelyModel extensions into separate files

Shared/Extensions/WriteFreelyModel+API.swift

@@ -0,0 +1,152 @@
+import Foundation
+import WriteFreely
+
+extension WriteFreelyModel {
+    func login(to server: URL, as username: String, password: String) {
+        if !hasNetworkConnection {
+            isPresentingNetworkErrorAlert = true
+            return
+        }
+        let secureProtocolPrefix = "https://"
+        let insecureProtocolPrefix = "http://"
+        var serverString = server.absoluteString
+        // If there's neither an http or https prefix, prepend "https://" to the server string.
+        if !(serverString.hasPrefix(secureProtocolPrefix) || serverString.hasPrefix(insecureProtocolPrefix)) {
+            serverString = secureProtocolPrefix + serverString
+        }
+        // If the server string is prefixed with http, upgrade to https before attempting to login.
+        if serverString.hasPrefix(insecureProtocolPrefix) {
+            serverString = serverString.replacingOccurrences(of: insecureProtocolPrefix, with: secureProtocolPrefix)
+        }
+        isLoggingIn = true
+        var serverURL = URL(string: serverString)!
+        if !serverURL.path.isEmpty {
+            serverURL.deleteLastPathComponent()
+        }
+        account.server = serverURL.absoluteString
+        client = WFClient(for: serverURL)
+        client?.login(username: username, password: password, completion: loginHandler)
+    }
+
+    func logout() {
+        if !hasNetworkConnection {
+            DispatchQueue.main.async { self.isPresentingNetworkErrorAlert = true }
+            return
+        }
+        guard let loggedInClient = client else {
+            do {
+                try purgeTokenFromKeychain(username: account.username, server: account.server)
+                account.logout()
+            } catch {
+                fatalError("Failed to log out persisted state")
+            }
+            return
+        }
+        loggedInClient.logout(completion: logoutHandler)
+    }
+
+    func fetchUserCollections() {
+        if !hasNetworkConnection {
+            DispatchQueue.main.async { self.isPresentingNetworkErrorAlert = true }
+            return
+        }
+        guard let loggedInClient = client else { return }
+        // We're starting the network request.
+        DispatchQueue.main.async {
+            self.isProcessingRequest = true
+        }
+        loggedInClient.getUserCollections(completion: fetchUserCollectionsHandler)
+    }
+
+    func fetchUserPosts() {
+        if !hasNetworkConnection {
+            DispatchQueue.main.async { self.isPresentingNetworkErrorAlert = true }
+            return
+        }
+        guard let loggedInClient = client else { return }
+        // We're starting the network request.
+        DispatchQueue.main.async {
+            self.isProcessingRequest = true
+        }
+        loggedInClient.getPosts(completion: fetchUserPostsHandler)
+    }
+
+    func publish(post: WFAPost) {
+        postToUpdate = nil
+
+        if !hasNetworkConnection {
+            DispatchQueue.main.async { self.isPresentingNetworkErrorAlert = true }
+            return
+        }
+        guard let loggedInClient = client else { return }
+        // We're starting the network request.
+        DispatchQueue.main.async {
+            self.isProcessingRequest = true
+        }
+
+        if post.language == nil {
+            if let languageCode = Locale.current.languageCode {
+                post.language = languageCode
+                post.rtl = Locale.characterDirection(forLanguage: languageCode) == .rightToLeft
+            }
+        }
+
+        var wfPost = WFPost(
+            body: post.body,
+            title: post.title.isEmpty ? "" : post.title,
+            appearance: post.appearance,
+            language: post.language,
+            rtl: post.rtl,
+            createdDate: post.createdDate
+        )
+
+        if let existingPostId = post.postId {
+            // This is an existing post.
+            postToUpdate = post
+            wfPost.postId = post.postId
+
+            loggedInClient.updatePost(
+                postId: existingPostId,
+                updatedPost: wfPost,
+                completion: publishHandler
+            )
+        } else {
+            // This is a new local draft.
+            loggedInClient.createPost(
+                post: wfPost, in: post.collectionAlias, completion: publishHandler
+            )
+        }
+    }
+
+    func updateFromServer(post: WFAPost) {
+        if !hasNetworkConnection {
+            DispatchQueue.main.async { self.isPresentingNetworkErrorAlert = true }
+            return
+        }
+        guard let loggedInClient = client else { return }
+        guard let postId = post.postId else { return }
+        // We're starting the network request.
+        DispatchQueue.main.async {
+            self.selectedPost = post
+            self.isProcessingRequest = true
+        }
+        loggedInClient.getPost(byId: postId, completion: updateFromServerHandler)
+    }
+
+    func move(post: WFAPost, from oldCollection: WFACollection?, to newCollection: WFACollection?) {
+        if !hasNetworkConnection {
+            DispatchQueue.main.async { self.isPresentingNetworkErrorAlert = true }
+            return
+        }
+        guard let loggedInClient = client,
+              let postId = post.postId else { return }
+        // We're starting the network request.
+        DispatchQueue.main.async {
+            self.isProcessingRequest = true
+        }
+
+        selectedPost = post
+        post.collectionAlias = newCollection?.alias
+        loggedInClient.movePost(postId: postId, to: newCollection?.alias, completion: movePostHandler)
+    }
+}

Shared/Extensions/WriteFreelyModel+APIHandlers.swift

@@ -0,0 +1,294 @@
+import Foundation
+import WriteFreely
+
+extension WriteFreelyModel {
+    func loginHandler(result: Result<WFUser, Error>) {
+        DispatchQueue.main.async {
+            self.isLoggingIn = false
+        }
+        do {
+            let user = try result.get()
+            fetchUserCollections()
+            fetchUserPosts()
+            saveTokenToKeychain(user.token, username: user.username, server: account.server)
+            DispatchQueue.main.async {
+                self.account.login(user)
+            }
+        } catch WFError.notFound {
+            DispatchQueue.main.async {
+                self.loginErrorMessage = AccountError.usernameNotFound.localizedDescription
+                self.isPresentingLoginErrorAlert = true
+            }
+        } catch WFError.unauthorized {
+            DispatchQueue.main.async {
+                self.loginErrorMessage = AccountError.invalidPassword.localizedDescription
+                self.isPresentingLoginErrorAlert = true
+            }
+        } catch {
+            if (error as NSError).domain == NSURLErrorDomain,
+               (error as NSError).code == -1003 {
+                DispatchQueue.main.async {
+                    self.loginErrorMessage = AccountError.serverNotFound.localizedDescription
+                    self.isPresentingLoginErrorAlert = true
+                }
+            } else {
+                DispatchQueue.main.async {
+                    self.loginErrorMessage = error.localizedDescription
+                    self.isPresentingLoginErrorAlert = true
+                }
+            }
+        }
+    }
+
+    func logoutHandler(result: Result<Bool, Error>) {
+        do {
+            _ = try result.get()
+            do {
+                try purgeTokenFromKeychain(username: account.user?.username, server: account.server)
+                client = nil
+                DispatchQueue.main.async {
+                    self.account.logout()
+                    LocalStorageManager().purgeUserCollections()
+                    self.posts.purgePublishedPosts()
+                }
+            } catch {
+                print("Something went wrong purging the token from the Keychain.")
+            }
+        } catch WFError.notFound {
+            // The user token is invalid or doesn't exist, so it's been invalidated by the server. Proceed with
+            // purging the token from the Keychain, destroying the client object, and setting the AccountModel to its
+            // logged-out state.
+            do {
+                try purgeTokenFromKeychain(username: account.user?.username, server: account.server)
+                client = nil
+                DispatchQueue.main.async {
+                    self.account.logout()
+                    LocalStorageManager().purgeUserCollections()
+                    self.posts.purgePublishedPosts()
+                }
+            } catch {
+                print("Something went wrong purging the token from the Keychain.")
+            }
+        } catch {
+            // We get a 'cannot parse response' (similar to what we were seeing in the Swift package) NSURLError here,
+            // so we're using a hacky workaround — if we get the NSURLError, but the AccountModel still thinks we're
+            // logged in, try calling the logout function again and see what we get.
+            // Conditional cast from 'Error' to 'NSError' always succeeds but is the only way to check error properties.
+            if (error as NSError).domain == NSURLErrorDomain,
+               (error as NSError).code == NSURLErrorCannotParseResponse {
+                if account.isLoggedIn {
+                    self.logout()
+                }
+            }
+        }
+    }
+
+    func fetchUserCollectionsHandler(result: Result<[WFCollection], Error>) {
+        // We're done with the network request.
+        DispatchQueue.main.async {
+            self.isProcessingRequest = false
+        }
+        do {
+            let fetchedCollections = try result.get()
+            for fetchedCollection in fetchedCollections {
+                DispatchQueue.main.async {
+                    let localCollection = WFACollection(context: LocalStorageManager.persistentContainer.viewContext)
+                    localCollection.alias = fetchedCollection.alias
+                    localCollection.blogDescription = fetchedCollection.description
+                    localCollection.email = fetchedCollection.email
+                    localCollection.isPublic = fetchedCollection.isPublic ?? false
+                    localCollection.styleSheet = fetchedCollection.styleSheet
+                    localCollection.title = fetchedCollection.title
+                    localCollection.url = fetchedCollection.url
+                }
+            }
+            DispatchQueue.main.async {
+                LocalStorageManager().saveContext()
+            }
+        } catch WFError.unauthorized {
+            DispatchQueue.main.async {
+                self.loginErrorMessage = "Something went wrong, please try logging in again."
+                self.isPresentingLoginErrorAlert = true
+            }
+            self.logout()
+        } catch {
+            print(error)
+        }
+    }
+
+    func fetchUserPostsHandler(result: Result<[WFPost], Error>) {
+        // We're done with the network request.
+        DispatchQueue.main.async {
+            self.isProcessingRequest = false
+        }
+        let request = WFAPost.createFetchRequest()
+        do {
+            let locallyCachedPosts = try LocalStorageManager.persistentContainer.viewContext.fetch(request)
+            do {
+                var postsToDelete = locallyCachedPosts.filter { $0.status != PostStatus.local.rawValue }
+                let fetchedPosts = try result.get()
+                for fetchedPost in fetchedPosts {
+                    if let managedPost = locallyCachedPosts.first(where: { $0.postId == fetchedPost.postId }) {
+                        DispatchQueue.main.async {
+                            managedPost.wasDeletedFromServer = false
+                            if let fetchedPostUpdatedDate = fetchedPost.updatedDate,
+                               let localPostUpdatedDate = managedPost.updatedDate {
+                                managedPost.hasNewerRemoteCopy = fetchedPostUpdatedDate > localPostUpdatedDate
+                            } else { print("Error: could not determine which copy of post is newer") }
+                            postsToDelete.removeAll(where: { $0.postId == fetchedPost.postId })
+                        }
+                    } else {
+                        DispatchQueue.main.async {
+                            let managedPost = WFAPost(context: LocalStorageManager.persistentContainer.viewContext)
+                            managedPost.postId = fetchedPost.postId
+                            managedPost.slug = fetchedPost.slug
+                            managedPost.appearance = fetchedPost.appearance
+                            managedPost.language = fetchedPost.language
+                            managedPost.rtl = fetchedPost.rtl ?? false
+                            managedPost.createdDate = fetchedPost.createdDate
+                            managedPost.updatedDate = fetchedPost.updatedDate
+                            managedPost.title = fetchedPost.title ?? ""
+                            managedPost.body = fetchedPost.body
+                            managedPost.collectionAlias = fetchedPost.collectionAlias
+                            managedPost.status = PostStatus.published.rawValue
+                            managedPost.wasDeletedFromServer = false
+                        }
+                    }
+                }
+                DispatchQueue.main.async {
+                    for post in postsToDelete { post.wasDeletedFromServer = true }
+                    LocalStorageManager().saveContext()
+                }
+            } catch {
+                print(error)
+            }
+        } catch WFError.unauthorized {
+            DispatchQueue.main.async {
+                self.loginErrorMessage = "Something went wrong, please try logging in again."
+                self.isPresentingLoginErrorAlert = true
+            }
+            self.logout()
+        } catch {
+            print("Error: Failed to fetch cached posts")
+        }
+    }
+
+    func publishHandler(result: Result<WFPost, Error>) {
+        // We're done with the network request.
+        DispatchQueue.main.async {
+            self.isProcessingRequest = false
+        }
+        // ⚠️ NOTE:
+        // The API does not return a collection alias, so we take care not to overwrite the
+        // cached post's collection alias with the 'nil' value from the fetched post.
+        // See: https://github.com/writeas/writefreely-swift/issues/20
+        do {
+            let fetchedPost = try result.get()
+            // If this is an updated post, check it against postToUpdate.
+            if let updatingPost = self.postToUpdate {
+                updatingPost.appearance = fetchedPost.appearance
+                updatingPost.body = fetchedPost.body
+                updatingPost.createdDate = fetchedPost.createdDate
+                updatingPost.language = fetchedPost.language
+                updatingPost.postId = fetchedPost.postId
+                updatingPost.rtl = fetchedPost.rtl ?? false
+                updatingPost.slug = fetchedPost.slug
+                updatingPost.status = PostStatus.published.rawValue
+                updatingPost.title = fetchedPost.title ?? ""
+                updatingPost.updatedDate = fetchedPost.updatedDate
+                DispatchQueue.main.async {
+                    LocalStorageManager().saveContext()
+                }
+            } else {
+                // Otherwise if it's a newly-published post, find it in the local store.
+                let request = WFAPost.createFetchRequest()
+                let matchBodyPredicate = NSPredicate(format: "body == %@", fetchedPost.body)
+                if let fetchedPostTitle = fetchedPost.title {
+                    let matchTitlePredicate = NSPredicate(format: "title == %@", fetchedPostTitle)
+                    request.predicate = NSCompoundPredicate(
+                        andPredicateWithSubpredicates: [
+                            matchTitlePredicate,
+                            matchBodyPredicate
+                        ]
+                    )
+                } else {
+                    request.predicate = matchBodyPredicate
+                }
+                do {
+                    let cachedPostsResults = try LocalStorageManager.persistentContainer.viewContext.fetch(request)
+                    guard let cachedPost = cachedPostsResults.first else { return }
+                    cachedPost.appearance = fetchedPost.appearance
+                    cachedPost.body = fetchedPost.body
+                    cachedPost.createdDate = fetchedPost.createdDate
+                    cachedPost.language = fetchedPost.language
+                    cachedPost.postId = fetchedPost.postId
+                    cachedPost.rtl = fetchedPost.rtl ?? false
+                    cachedPost.slug = fetchedPost.slug
+                    cachedPost.status = PostStatus.published.rawValue
+                    cachedPost.title = fetchedPost.title ?? ""
+                    cachedPost.updatedDate = fetchedPost.updatedDate
+                    DispatchQueue.main.async {
+                        LocalStorageManager().saveContext()
+                    }
+                } catch {
+                    print("Error: Failed to fetch cached posts")
+                }
+            }
+        } catch {
+            print(error)
+        }
+    }
+
+    func updateFromServerHandler(result: Result<WFPost, Error>) {
+        // We're done with the network request.
+        DispatchQueue.main.async {
+            self.isProcessingRequest = false
+        }
+        // ⚠️ NOTE:
+        // The API does not return a collection alias, so we take care not to overwrite the
+        // cached post's collection alias with the 'nil' value from the fetched post.
+        // See: https://github.com/writeas/writefreely-swift/issues/20
+        do {
+            let fetchedPost = try result.get()
+            guard let cachedPost = self.selectedPost else { return }
+            cachedPost.appearance = fetchedPost.appearance
+            cachedPost.body = fetchedPost.body
+            cachedPost.createdDate = fetchedPost.createdDate
+            cachedPost.language = fetchedPost.language
+            cachedPost.postId = fetchedPost.postId
+            cachedPost.rtl = fetchedPost.rtl ?? false
+            cachedPost.slug = fetchedPost.slug
+            cachedPost.status = PostStatus.published.rawValue
+            cachedPost.title = fetchedPost.title ?? ""
+            cachedPost.updatedDate = fetchedPost.updatedDate
+            cachedPost.hasNewerRemoteCopy = false
+            DispatchQueue.main.async {
+                LocalStorageManager().saveContext()
+            }
+        } catch {
+            print(error)
+        }
+    }
+
+    func movePostHandler(result: Result<Bool, Error>) {
+        // We're done with the network request.
+        DispatchQueue.main.async {
+            self.isProcessingRequest = false
+        }
+        do {
+            let succeeded = try result.get()
+            if succeeded {
+                if let post = selectedPost {
+                    updateFromServer(post: post)
+                } else {
+                    return
+                }
+            }
+        } catch {
+            DispatchQueue.main.async {
+                LocalStorageManager.persistentContainer.viewContext.rollback()
+            }
+            print(error)
+        }
+    }
+}

Shared/Extensions/WriteFreelyModel+Keychain.swift

@@ -0,0 +1,53 @@
+import Foundation
+
+extension WriteFreelyModel {
+    func saveTokenToKeychain(_ token: String, username: String?, server: String) {
+        let query: [String: Any] = [
+            kSecClass as String: kSecClassGenericPassword,
+            kSecValueData as String: token.data(using: .utf8)!,
+            kSecAttrAccount as String: username ?? "anonymous",
+            kSecAttrService as String: server
+        ]
+        let status = SecItemAdd(query as CFDictionary, nil)
+        guard status == errSecDuplicateItem || status == errSecSuccess else {
+            fatalError("Error storing in Keychain with OSStatus: \(status)")
+        }
+    }
+
+    func purgeTokenFromKeychain(username: String?, server: String) throws {
+        let query: [String: Any] = [
+            kSecClass as String: kSecClassGenericPassword,
+            kSecAttrAccount as String: username ?? "anonymous",
+            kSecAttrService as String: server
+        ]
+        let status = SecItemDelete(query as CFDictionary)
+        guard status == errSecSuccess || status == errSecItemNotFound else {
+            fatalError("Error deleting from Keychain with OSStatus: \(status)")
+        }
+    }
+
+    func fetchTokenFromKeychain(username: String?, server: String) -> String? {
+        let query: [String: Any] = [
+            kSecClass as String: kSecClassGenericPassword,
+            kSecAttrAccount as String: username ?? "anonymous",
+            kSecAttrService as String: server,
+            kSecMatchLimit as String: kSecMatchLimitOne,
+            kSecReturnAttributes as String: true,
+            kSecReturnData as String: true
+        ]
+        var secItem: CFTypeRef?
+        let status = SecItemCopyMatching(query as CFDictionary, &secItem)
+        guard status != errSecItemNotFound else {
+            return nil
+        }
+        guard status == errSecSuccess else {
+            fatalError("Error fetching from Keychain with OSStatus: \(status)")
+        }
+        guard let existingSecItem = secItem as? [String: Any],
+              let tokenData = existingSecItem[kSecValueData as String] as? Data,
+              let token = String(data: tokenData, encoding: .utf8) else {
+            return nil
+        }
+        return token
+    }
+}

Shared/Models/WriteFreelyModel.swift

@@ -33,11 +33,11 @@ class WriteFreelyModel: ObservableObject {
     let licensesURL = URL(string: "https://github.com/writeas/writefreely-swiftui-multiplatform/tree/main/Shared/Resources/Licenses")!
     // swiftlint:enable line_length
 
-    private var client: WFClient?
+    internal var client: WFClient?
     private let defaults = UserDefaults.standard
     private let monitor = NWPathMonitor()
     private let queue = DispatchQueue(label: "NetworkMonitor")
-    private var postToUpdate: WFAPost?
+    internal var postToUpdate: WFAPost?
 
     init() {
         DispatchQueue.main.async {
@@ -72,500 +72,3 @@ class WriteFreelyModel: ObservableObject {
         monitor.start(queue: queue)
     }
 }
-
-// MARK: - WriteFreelyModel API
-
-extension WriteFreelyModel {
-    func login(to server: URL, as username: String, password: String) {
-        if !hasNetworkConnection {
-            isPresentingNetworkErrorAlert = true
-            return
-        }
-        let secureProtocolPrefix = "https://"
-        let insecureProtocolPrefix = "http://"
-        var serverString = server.absoluteString
-        // If there's neither an http or https prefix, prepend "https://" to the server string.
-        if !(serverString.hasPrefix(secureProtocolPrefix) || serverString.hasPrefix(insecureProtocolPrefix)) {
-            serverString = secureProtocolPrefix + serverString
-        }
-        // If the server string is prefixed with http, upgrade to https before attempting to login.
-        if serverString.hasPrefix(insecureProtocolPrefix) {
-            serverString = serverString.replacingOccurrences(of: insecureProtocolPrefix, with: secureProtocolPrefix)
-        }
-        isLoggingIn = true
-        var serverURL = URL(string: serverString)!
-        if !serverURL.path.isEmpty {
-            serverURL.deleteLastPathComponent()
-        }
-        account.server = serverURL.absoluteString
-        client = WFClient(for: serverURL)
-        client?.login(username: username, password: password, completion: loginHandler)
-    }
-
-    func logout() {
-        if !hasNetworkConnection {
-            DispatchQueue.main.async { self.isPresentingNetworkErrorAlert = true }
-            return
-        }
-        guard let loggedInClient = client else {
-            do {
-                try purgeTokenFromKeychain(username: account.username, server: account.server)
-                account.logout()
-            } catch {
-                fatalError("Failed to log out persisted state")
-            }
-            return
-        }
-        loggedInClient.logout(completion: logoutHandler)
-    }
-
-    func fetchUserCollections() {
-        if !hasNetworkConnection {
-            DispatchQueue.main.async { self.isPresentingNetworkErrorAlert = true }
-            return
-        }
-        guard let loggedInClient = client else { return }
-        // We're starting the network request.
-        DispatchQueue.main.async {
-            self.isProcessingRequest = true
-        }
-        loggedInClient.getUserCollections(completion: fetchUserCollectionsHandler)
-    }
-
-    func fetchUserPosts() {
-        if !hasNetworkConnection {
-            DispatchQueue.main.async { self.isPresentingNetworkErrorAlert = true }
-            return
-        }
-        guard let loggedInClient = client else { return }
-        // We're starting the network request.
-        DispatchQueue.main.async {
-            self.isProcessingRequest = true
-        }
-        loggedInClient.getPosts(completion: fetchUserPostsHandler)
-    }
-
-    func publish(post: WFAPost) {
-        postToUpdate = nil
-
-        if !hasNetworkConnection {
-            DispatchQueue.main.async { self.isPresentingNetworkErrorAlert = true }
-            return
-        }
-        guard let loggedInClient = client else { return }
-        // We're starting the network request.
-        DispatchQueue.main.async {
-            self.isProcessingRequest = true
-        }
-
-        if post.language == nil {
-            if let languageCode = Locale.current.languageCode {
-                post.language = languageCode
-                post.rtl = Locale.characterDirection(forLanguage: languageCode) == .rightToLeft
-            }
-        }
-
-        var wfPost = WFPost(
-            body: post.body,
-            title: post.title.isEmpty ? "" : post.title,
-            appearance: post.appearance,
-            language: post.language,
-            rtl: post.rtl,
-            createdDate: post.createdDate
-        )
-
-        if let existingPostId = post.postId {
-            // This is an existing post.
-            postToUpdate = post
-            wfPost.postId = post.postId
-
-            loggedInClient.updatePost(
-                postId: existingPostId,
-                updatedPost: wfPost,
-                completion: publishHandler
-            )
-        } else {
-            // This is a new local draft.
-            loggedInClient.createPost(
-                post: wfPost, in: post.collectionAlias, completion: publishHandler
-            )
-        }
-    }
-
-    func updateFromServer(post: WFAPost) {
-        if !hasNetworkConnection {
-            DispatchQueue.main.async { self.isPresentingNetworkErrorAlert = true }
-            return
-        }
-        guard let loggedInClient = client else { return }
-        guard let postId = post.postId else { return }
-        // We're starting the network request.
-        DispatchQueue.main.async {
-            self.selectedPost = post
-            self.isProcessingRequest = true
-        }
-        loggedInClient.getPost(byId: postId, completion: updateFromServerHandler)
-    }
-
-    func move(post: WFAPost, from oldCollection: WFACollection?, to newCollection: WFACollection?) {
-        if !hasNetworkConnection {
-            DispatchQueue.main.async { self.isPresentingNetworkErrorAlert = true }
-            return
-        }
-        guard let loggedInClient = client,
-              let postId = post.postId else { return }
-        // We're starting the network request.
-        DispatchQueue.main.async {
-            self.isProcessingRequest = true
-        }
-
-        selectedPost = post
-        post.collectionAlias = newCollection?.alias
-        loggedInClient.movePost(postId: postId, to: newCollection?.alias, completion: movePostHandler)
-    }
-}
-
-private extension WriteFreelyModel {
-    func loginHandler(result: Result<WFUser, Error>) {
-        DispatchQueue.main.async {
-            self.isLoggingIn = false
-        }
-        do {
-            let user = try result.get()
-            fetchUserCollections()
-            fetchUserPosts()
-            saveTokenToKeychain(user.token, username: user.username, server: account.server)
-            DispatchQueue.main.async {
-                self.account.login(user)
-            }
-        } catch WFError.notFound {
-            DispatchQueue.main.async {
-                self.loginErrorMessage = AccountError.usernameNotFound.localizedDescription
-                self.isPresentingLoginErrorAlert = true
-            }
-        } catch WFError.unauthorized {
-            DispatchQueue.main.async {
-                self.loginErrorMessage = AccountError.invalidPassword.localizedDescription
-                self.isPresentingLoginErrorAlert = true
-            }
-        } catch {
-            if (error as NSError).domain == NSURLErrorDomain,
-               (error as NSError).code == -1003 {
-                DispatchQueue.main.async {
-                    self.loginErrorMessage = AccountError.serverNotFound.localizedDescription
-                    self.isPresentingLoginErrorAlert = true
-                }
-            } else {
-                DispatchQueue.main.async {
-                    self.loginErrorMessage = error.localizedDescription
-                    self.isPresentingLoginErrorAlert = true
-                }
-            }
-        }
-    }
-
-    func logoutHandler(result: Result<Bool, Error>) {
-        do {
-            _ = try result.get()
-            do {
-                try purgeTokenFromKeychain(username: account.user?.username, server: account.server)
-                client = nil
-                DispatchQueue.main.async {
-                    self.account.logout()
-                    LocalStorageManager().purgeUserCollections()
-                    self.posts.purgePublishedPosts()
-                }
-            } catch {
-                print("Something went wrong purging the token from the Keychain.")
-            }
-        } catch WFError.notFound {
-            // The user token is invalid or doesn't exist, so it's been invalidated by the server. Proceed with
-            // purging the token from the Keychain, destroying the client object, and setting the AccountModel to its
-            // logged-out state.
-            do {
-                try purgeTokenFromKeychain(username: account.user?.username, server: account.server)
-                client = nil
-                DispatchQueue.main.async {
-                    self.account.logout()
-                    LocalStorageManager().purgeUserCollections()
-                    self.posts.purgePublishedPosts()
-                }
-            } catch {
-                print("Something went wrong purging the token from the Keychain.")
-            }
-        } catch {
-            // We get a 'cannot parse response' (similar to what we were seeing in the Swift package) NSURLError here,
-            // so we're using a hacky workaround — if we get the NSURLError, but the AccountModel still thinks we're
-            // logged in, try calling the logout function again and see what we get.
-            // Conditional cast from 'Error' to 'NSError' always succeeds but is the only way to check error properties.
-            if (error as NSError).domain == NSURLErrorDomain,
-               (error as NSError).code == NSURLErrorCannotParseResponse {
-                if account.isLoggedIn {
-                    self.logout()
-                }
-            }
-        }
-    }
-
-    func fetchUserCollectionsHandler(result: Result<[WFCollection], Error>) {
-        // We're done with the network request.
-        DispatchQueue.main.async {
-            self.isProcessingRequest = false
-        }
-        do {
-            let fetchedCollections = try result.get()
-            for fetchedCollection in fetchedCollections {
-                DispatchQueue.main.async {
-                    let localCollection = WFACollection(context: LocalStorageManager.persistentContainer.viewContext)
-                    localCollection.alias = fetchedCollection.alias
-                    localCollection.blogDescription = fetchedCollection.description
-                    localCollection.email = fetchedCollection.email
-                    localCollection.isPublic = fetchedCollection.isPublic ?? false
-                    localCollection.styleSheet = fetchedCollection.styleSheet
-                    localCollection.title = fetchedCollection.title
-                    localCollection.url = fetchedCollection.url
-                }
-            }
-            DispatchQueue.main.async {
-                LocalStorageManager().saveContext()
-            }
-        } catch WFError.unauthorized {
-            DispatchQueue.main.async {
-                self.loginErrorMessage = "Something went wrong, please try logging in again."
-                self.isPresentingLoginErrorAlert = true
-            }
-            self.logout()
-        } catch {
-            print(error)
-        }
-    }
-
-    func fetchUserPostsHandler(result: Result<[WFPost], Error>) {
-        // We're done with the network request.
-        DispatchQueue.main.async {
-            self.isProcessingRequest = false
-        }
-        let request = WFAPost.createFetchRequest()
-        do {
-            let locallyCachedPosts = try LocalStorageManager.persistentContainer.viewContext.fetch(request)
-            do {
-                var postsToDelete = locallyCachedPosts.filter { $0.status != PostStatus.local.rawValue }
-                let fetchedPosts = try result.get()
-                for fetchedPost in fetchedPosts {
-                    if let managedPost = locallyCachedPosts.first(where: { $0.postId == fetchedPost.postId }) {
-                        DispatchQueue.main.async {
-                            managedPost.wasDeletedFromServer = false
-                            if let fetchedPostUpdatedDate = fetchedPost.updatedDate,
-                               let localPostUpdatedDate = managedPost.updatedDate {
-                                managedPost.hasNewerRemoteCopy = fetchedPostUpdatedDate > localPostUpdatedDate
-                            } else { print("Error: could not determine which copy of post is newer") }
-                            postsToDelete.removeAll(where: { $0.postId == fetchedPost.postId })
-                        }
-                    } else {
-                        DispatchQueue.main.async {
-                            let managedPost = WFAPost(context: LocalStorageManager.persistentContainer.viewContext)
-                            managedPost.postId = fetchedPost.postId
-                            managedPost.slug = fetchedPost.slug
-                            managedPost.appearance = fetchedPost.appearance
-                            managedPost.language = fetchedPost.language
-                            managedPost.rtl = fetchedPost.rtl ?? false
-                            managedPost.createdDate = fetchedPost.createdDate
-                            managedPost.updatedDate = fetchedPost.updatedDate
-                            managedPost.title = fetchedPost.title ?? ""
-                            managedPost.body = fetchedPost.body
-                            managedPost.collectionAlias = fetchedPost.collectionAlias
-                            managedPost.status = PostStatus.published.rawValue
-                            managedPost.wasDeletedFromServer = false
-                        }
-                    }
-                }
-                DispatchQueue.main.async {
-                    for post in postsToDelete { post.wasDeletedFromServer = true }
-                    LocalStorageManager().saveContext()
-                }
-            } catch {
-                print(error)
-            }
-        } catch WFError.unauthorized {
-            DispatchQueue.main.async {
-                self.loginErrorMessage = "Something went wrong, please try logging in again."
-                self.isPresentingLoginErrorAlert = true
-            }
-            self.logout()
-        } catch {
-            print("Error: Failed to fetch cached posts")
-        }
-    }
-
-    func publishHandler(result: Result<WFPost, Error>) {
-        // We're done with the network request.
-        DispatchQueue.main.async {
-            self.isProcessingRequest = false
-        }
-        // ⚠️ NOTE:
-        // The API does not return a collection alias, so we take care not to overwrite the
-        // cached post's collection alias with the 'nil' value from the fetched post.
-        // See: https://github.com/writeas/writefreely-swift/issues/20
-        do {
-            let fetchedPost = try result.get()
-            // If this is an updated post, check it against postToUpdate.
-            if let updatingPost = self.postToUpdate {
-                updatingPost.appearance = fetchedPost.appearance
-                updatingPost.body = fetchedPost.body
-                updatingPost.createdDate = fetchedPost.createdDate
-                updatingPost.language = fetchedPost.language
-                updatingPost.postId = fetchedPost.postId
-                updatingPost.rtl = fetchedPost.rtl ?? false
-                updatingPost.slug = fetchedPost.slug
-                updatingPost.status = PostStatus.published.rawValue
-                updatingPost.title = fetchedPost.title ?? ""
-                updatingPost.updatedDate = fetchedPost.updatedDate
-                DispatchQueue.main.async {
-                    LocalStorageManager().saveContext()
-                }
-            } else {
-                // Otherwise if it's a newly-published post, find it in the local store.
-                let request = WFAPost.createFetchRequest()
-                let matchBodyPredicate = NSPredicate(format: "body == %@", fetchedPost.body)
-                if let fetchedPostTitle = fetchedPost.title {
-                    let matchTitlePredicate = NSPredicate(format: "title == %@", fetchedPostTitle)
-                    request.predicate = NSCompoundPredicate(
-                        andPredicateWithSubpredicates: [
-                            matchTitlePredicate,
-                            matchBodyPredicate
-                        ]
-                    )
-                } else {
-                    request.predicate = matchBodyPredicate
-                }
-                do {
-                    let cachedPostsResults = try LocalStorageManager.persistentContainer.viewContext.fetch(request)
-                    guard let cachedPost = cachedPostsResults.first else { return }
-                    cachedPost.appearance = fetchedPost.appearance
-                    cachedPost.body = fetchedPost.body
-                    cachedPost.createdDate = fetchedPost.createdDate
-                    cachedPost.language = fetchedPost.language
-                    cachedPost.postId = fetchedPost.postId
-                    cachedPost.rtl = fetchedPost.rtl ?? false
-                    cachedPost.slug = fetchedPost.slug
-                    cachedPost.status = PostStatus.published.rawValue
-                    cachedPost.title = fetchedPost.title ?? ""
-                    cachedPost.updatedDate = fetchedPost.updatedDate
-                    DispatchQueue.main.async {
-                        LocalStorageManager().saveContext()
-                    }
-                } catch {
-                    print("Error: Failed to fetch cached posts")
-                }
-            }
-        } catch {
-            print(error)
-        }
-    }
-
-    func updateFromServerHandler(result: Result<WFPost, Error>) {
-        // We're done with the network request.
-        DispatchQueue.main.async {
-            self.isProcessingRequest = false
-        }
-        // ⚠️ NOTE:
-        // The API does not return a collection alias, so we take care not to overwrite the
-        // cached post's collection alias with the 'nil' value from the fetched post.
-        // See: https://github.com/writeas/writefreely-swift/issues/20
-        do {
-            let fetchedPost = try result.get()
-            guard let cachedPost = self.selectedPost else { return }
-            cachedPost.appearance = fetchedPost.appearance
-            cachedPost.body = fetchedPost.body
-            cachedPost.createdDate = fetchedPost.createdDate
-            cachedPost.language = fetchedPost.language
-            cachedPost.postId = fetchedPost.postId
-            cachedPost.rtl = fetchedPost.rtl ?? false
-            cachedPost.slug = fetchedPost.slug
-            cachedPost.status = PostStatus.published.rawValue
-            cachedPost.title = fetchedPost.title ?? ""
-            cachedPost.updatedDate = fetchedPost.updatedDate
-            cachedPost.hasNewerRemoteCopy = false
-            DispatchQueue.main.async {
-                LocalStorageManager().saveContext()
-            }
-        } catch {
-            print(error)
-        }
-    }
-
-    func movePostHandler(result: Result<Bool, Error>) {
-        // We're done with the network request.
-        DispatchQueue.main.async {
-            self.isProcessingRequest = false
-        }
-        do {
-            let succeeded = try result.get()
-            if succeeded {
-                if let post = selectedPost {
-                    updateFromServer(post: post)
-                } else {
-                    return
-                }
-            }
-        } catch {
-            DispatchQueue.main.async {
-                LocalStorageManager.persistentContainer.viewContext.rollback()
-            }
-            print(error)
-        }
-    }
-}
-
-private extension WriteFreelyModel {
-    // MARK: - Keychain Helpers
-    func saveTokenToKeychain(_ token: String, username: String?, server: String) {
-        let query: [String: Any] = [
-            kSecClass as String: kSecClassGenericPassword,
-            kSecValueData as String: token.data(using: .utf8)!,
-            kSecAttrAccount as String: username ?? "anonymous",
-            kSecAttrService as String: server
-        ]
-        let status = SecItemAdd(query as CFDictionary, nil)
-        guard status == errSecDuplicateItem || status == errSecSuccess else {
-            fatalError("Error storing in Keychain with OSStatus: \(status)")
-        }
-    }
-
-    func purgeTokenFromKeychain(username: String?, server: String) throws {
-        let query: [String: Any] = [
-            kSecClass as String: kSecClassGenericPassword,
-            kSecAttrAccount as String: username ?? "anonymous",
-            kSecAttrService as String: server
-        ]
-        let status = SecItemDelete(query as CFDictionary)
-        guard status == errSecSuccess || status == errSecItemNotFound else {
-            fatalError("Error deleting from Keychain with OSStatus: \(status)")
-        }
-    }
-
-    func fetchTokenFromKeychain(username: String?, server: String) -> String? {
-        let query: [String: Any] = [
-            kSecClass as String: kSecClassGenericPassword,
-            kSecAttrAccount as String: username ?? "anonymous",
-            kSecAttrService as String: server,
-            kSecMatchLimit as String: kSecMatchLimitOne,
-            kSecReturnAttributes as String: true,
-            kSecReturnData as String: true
-        ]
-        var secItem: CFTypeRef?
-        let status = SecItemCopyMatching(query as CFDictionary, &secItem)
-        guard status != errSecItemNotFound else {
-            return nil
-        }
-        guard status == errSecSuccess else {
-            fatalError("Error fetching from Keychain with OSStatus: \(status)")
-        }
-        guard let existingSecItem = secItem as? [String: Any],
-              let tokenData = existingSecItem[kSecValueData as String] as? Data,
-              let token = String(data: tokenData, encoding: .utf8) else {
-            return nil
-        }
-        return token
-    }
-}

WriteFreely-MultiPlatform.xcodeproj/project.pbxproj

@@ -59,6 +59,12 @@
 		17A67CAF251A5DD7002F163D /* PostEditorView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 17A67CAE251A5DD7002F163D /* PostEditorView.swift */; };
 		17AD0A5E25489E810057D763 /* PostTitleTextView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 17AD0A5D25489E810057D763 /* PostTitleTextView.swift */; };
 		17AD0A6425489E900057D763 /* PostBodyTextView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 17AD0A6325489E900057D763 /* PostBodyTextView.swift */; };
+		17B37C4B25C8661300FE75E9 /* WriteFreelyModel+Keychain.swift in Sources */ = {isa = PBXBuildFile; fileRef = 17B37C4A25C8661300FE75E9 /* WriteFreelyModel+Keychain.swift */; };
+		17B37C4C25C8661300FE75E9 /* WriteFreelyModel+Keychain.swift in Sources */ = {isa = PBXBuildFile; fileRef = 17B37C4A25C8661300FE75E9 /* WriteFreelyModel+Keychain.swift */; };
+		17B37C5625C8679800FE75E9 /* WriteFreelyModel+API.swift in Sources */ = {isa = PBXBuildFile; fileRef = 17B37C5525C8679800FE75E9 /* WriteFreelyModel+API.swift */; };
+		17B37C5725C8679800FE75E9 /* WriteFreelyModel+API.swift in Sources */ = {isa = PBXBuildFile; fileRef = 17B37C5525C8679800FE75E9 /* WriteFreelyModel+API.swift */; };
+		17B37C5D25C8698900FE75E9 /* WriteFreelyModel+APIHandlers.swift in Sources */ = {isa = PBXBuildFile; fileRef = 17B37C5C25C8698900FE75E9 /* WriteFreelyModel+APIHandlers.swift */; };
+		17B37C5E25C8698900FE75E9 /* WriteFreelyModel+APIHandlers.swift in Sources */ = {isa = PBXBuildFile; fileRef = 17B37C5C25C8698900FE75E9 /* WriteFreelyModel+APIHandlers.swift */; };
 		17B3E965250FAA9000EE9748 /* LaunchScreen.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = 17B3E964250FAA9000EE9748 /* LaunchScreen.storyboard */; };
 		17B5103B2515448D00E9631F /* Credits.rtf in Resources */ = {isa = PBXBuildFile; fileRef = 17B5103A2515448D00E9631F /* Credits.rtf */; };
 		17B996D82502D23E0017B536 /* WFAPost+CoreDataClass.swift in Sources */ = {isa = PBXBuildFile; fileRef = 17B996D62502D23E0017B536 /* WFAPost+CoreDataClass.swift */; };
@@ -155,6 +161,9 @@
 		17A67CAE251A5DD7002F163D /* PostEditorView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PostEditorView.swift; sourceTree = "<group>"; };
 		17AD0A5D25489E810057D763 /* PostTitleTextView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PostTitleTextView.swift; sourceTree = "<group>"; };
 		17AD0A6325489E900057D763 /* PostBodyTextView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PostBodyTextView.swift; sourceTree = "<group>"; };
+		17B37C4A25C8661300FE75E9 /* WriteFreelyModel+Keychain.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "WriteFreelyModel+Keychain.swift"; sourceTree = "<group>"; };
+		17B37C5525C8679800FE75E9 /* WriteFreelyModel+API.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "WriteFreelyModel+API.swift"; sourceTree = "<group>"; };
+		17B37C5C25C8698900FE75E9 /* WriteFreelyModel+APIHandlers.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "WriteFreelyModel+APIHandlers.swift"; sourceTree = "<group>"; };
 		17B3E964250FAA9000EE9748 /* LaunchScreen.storyboard */ = {isa = PBXFileReference; lastKnownFileType = file.storyboard; path = LaunchScreen.storyboard; sourceTree = "<group>"; };
 		17B5103A2515448D00E9631F /* Credits.rtf */ = {isa = PBXFileReference; lastKnownFileType = text.rtf; path = Credits.rtf; sourceTree = "<group>"; };
 		17B68D4F25A4FED2005ED37C /* Sparkle-License.txt */ = {isa = PBXFileReference; lastKnownFileType = text; path = "Sparkle-License.txt"; sourceTree = "<group>"; };
@@ -261,6 +270,9 @@
 			children = (
 				17C42E6F250AA12200072984 /* NSManagedObjectContext+ExecuteAndMergeChanges.swift */,
 				17480CA4251272EE00EB7765 /* Bundle+AppVersion.swift */,
+				17B37C5525C8679800FE75E9 /* WriteFreelyModel+API.swift */,
+				17B37C5C25C8698900FE75E9 /* WriteFreelyModel+APIHandlers.swift */,
+				17B37C4A25C8661300FE75E9 /* WriteFreelyModel+Keychain.swift */,
 			);
 			path = Extensions;
 			sourceTree = "<group>";
@@ -723,14 +735,17 @@
 			files = (
 				17DF32AC24C87D3500BCE2E3 /* ContentView.swift in Sources */,
 				173E19D1254318F600440F0F /* RemoteChangePromptView.swift in Sources */,
+				17B37C5625C8679800FE75E9 /* WriteFreelyModel+API.swift in Sources */,
 				17C42E622507D8E600072984 /* PostStatus.swift in Sources */,
 				1756DBBA24FED45500207AB8 /* LocalStorageManager.swift in Sources */,
 				1756AE8124CB844500FD7257 /* View+Keyboard.swift in Sources */,
 				17C42E652509237800072984 /* PostListFilteredView.swift in Sources */,
 				170DFA34251BBC44001D82A0 /* PostEditorModel.swift in Sources */,
 				17120DAC24E1B99F002B9F6C /* AccountLoginView.swift in Sources */,
+				17B37C4B25C8661300FE75E9 /* WriteFreelyModel+Keychain.swift in Sources */,
 				17480CA5251272EE00EB7765 /* Bundle+AppVersion.swift in Sources */,
 				17AD0A6425489E900057D763 /* PostBodyTextView.swift in Sources */,
+				17B37C5D25C8698900FE75E9 /* WriteFreelyModel+APIHandlers.swift in Sources */,
 				17AD0A5E25489E810057D763 /* PostTitleTextView.swift in Sources */,
 				17120DA924E1B2F5002B9F6C /* AccountLogoutView.swift in Sources */,
 				171BFDFA24D4AF8300888236 /* CollectionListView.swift in Sources */,
@@ -786,15 +801,18 @@
 				171BFDFB24D4AF8300888236 /* CollectionListView.swift in Sources */,
 				17A67CAF251A5DD7002F163D /* PostEditorView.swift in Sources */,
 				17DF32AB24C87D3500BCE2E3 /* WriteFreely_MultiPlatformApp.swift in Sources */,
+				17B37C5725C8679800FE75E9 /* WriteFreelyModel+API.swift in Sources */,
 				17A5388C24DDC83F00DEFF9A /* AccountModel.swift in Sources */,
 				17B996D92502D23E0017B536 /* WFAPost+CoreDataClass.swift in Sources */,
 				1756DBB824FED3A400207AB8 /* LocalStorageModel.xcdatamodeld in Sources */,
+				17B37C4C25C8661300FE75E9 /* WriteFreelyModel+Keychain.swift in Sources */,
 				17A5389324DDED0000DEFF9A /* PreferencesView.swift in Sources */,
 				1756AE6F24CB255B00FD7257 /* PostListModel.swift in Sources */,
 				1756DC0224FEE18400207AB8 /* WFACollection+CoreDataClass.swift in Sources */,
 				1756DBB424FECDBB00207AB8 /* PostEditorStatusToolbarView.swift in Sources */,
 				17A5388F24DDEC7400DEFF9A /* AccountView.swift in Sources */,
 				1780F6EF25895EDB00FE45FF /* PostCommands.swift in Sources */,
+				17B37C5E25C8698900FE75E9 /* WriteFreelyModel+APIHandlers.swift in Sources */,
 				170DFA35251BBC44001D82A0 /* PostEditorModel.swift in Sources */,
 				1756AE7524CB26FA00FD7257 /* PostCellView.swift in Sources */,
 				17A5388824DDA31F00DEFF9A /* MacAccountView.swift in Sources */,