Add methods for deleting local downloads and clear downloaded files o…

…n logout

DemoApp/StreamChat/Components/DemoChatChannelListRouter.swift

@@ -519,12 +519,18 @@ final class DemoChatChannelListRouter: ChatChannelListRouter {
                     }
                 }
             }),
-            .init(title: "Delete Downloaded Attachments", handler: { _ in
-                guard FileManager.default.fileExists(atPath: URL.streamAttachmentDownloadsDirectory.path) else { return }
+            .init(title: "Delete Downloaded Attachments", handler: { [unowned self] _ in
                 do {
-                    try FileManager.default.removeItem(at: .streamAttachmentDownloadsDirectory)
+                    let connectedUser = try self.rootViewController.controller.client.makeConnectedUser()
+                    Task {
+                        do {
+                            try await connectedUser.deleteAllAttachmentLocalDownloads()
+                        } catch {
+                            self.rootViewController.presentAlert(title: error.localizedDescription)
+                        }
+                    }
                 } catch {
-                    log.debug("Failed to delete downloaded attachments with error: \(error.localizedDescription)")
+                    self.rootViewController.presentAlert(title: error.localizedDescription)
                 }
             })
         ])

Sources/StreamChat/Controllers/CurrentUserController/CurrentUserController.swift

@@ -256,6 +256,18 @@ public extension CurrentChatUserController {
             }
         }
     }
+
+    /// Deletes all the local downloads of file attachments.
+    ///
+    /// - Parameter completion: Called when files have been deleted or when an error occured.
+    func deleteAllAttachmentLocalDownloads(completion: ((Error?) -> Void)? = nil) {
+        currentUserUpdater.deleteAllAttachmentLocalDownloads { error in
+            guard let completion else { return }
+            self.callback {
+                completion(error)
+            }
+        }
+    }
 
     /// Fetches all the unread information from the current user.
     ///

Sources/StreamChat/Controllers/MessageController/MessageController.swift

@@ -670,7 +670,24 @@ public class ChatMessageController: DataController, DelegateCallable, DataStoreP
     ///   - id: The id of the file attachment.
     ///   - completion: A completion block with a file attachment containing the downloading state.
     public func downloadAttachment(with id: AttachmentId, completion: @escaping (Result<ChatMessageFileAttachment, Error>) -> Void) {
-        messageUpdater.downloadAttachment(with: id, completion: completion)
+        messageUpdater.downloadAttachment(with: id) { result in
+            self.callback {
+                completion(result)
+            }
+        }
+    }
+
+    /// Deletes the locally downloaded file.
+    ///
+    /// - Parameters:
+    ///   - attachmentId: The id of the attachment.
+    ///   - completion: A completion block with an error if the deletion failed.
+    public func deleteLocalAttachmentDownload(for attachmentId: AttachmentId, completion: ((Error?) -> Void)? = nil) {
+        messageUpdater.deleteLocalAttachmentDownload(for: attachmentId) { error in
+            self.callback {
+                completion?(error)
+            }
+        }
     }
 
     /// Updates local state of attachment with provided `id` to be enqueued by attachment uploader.

Sources/StreamChat/Database/DTOs/AttachmentDTO.swift

@@ -80,6 +80,13 @@ class AttachmentDTO: NSManagedObject {
         return new
     }
 
+    static func downloadedFetchRequest() -> NSFetchRequest<AttachmentDTO> {
+        let request = NSFetchRequest<AttachmentDTO>(entityName: AttachmentDTO.entityName)
+        request.sortDescriptors = [NSSortDescriptor(keyPath: \AttachmentDTO.id, ascending: true)]
+        request.predicate = NSPredicate(format: "localStateRaw == %@", LocalAttachmentState.downloaded.rawValue)
+        return request
+    }
+
     static func pendingUploadFetchRequest() -> NSFetchRequest<AttachmentDTO> {
         let request = NSFetchRequest<AttachmentDTO>(entityName: AttachmentDTO.entityName)
         request.sortDescriptors = [NSSortDescriptor(keyPath: \AttachmentDTO.id, ascending: true)]
@@ -93,6 +100,13 @@ class AttachmentDTO: NSManagedObject {
         request.predicate = NSPredicate(format: "localStateRaw == %@", LocalAttachmentState.uploading(progress: 0).rawValue)
         return load(by: request, context: context)
     }
+
+    static func loadAllDownloadedAttachments(context: NSManagedObjectContext) -> [AttachmentDTO] {
+        let request = NSFetchRequest<AttachmentDTO>(entityName: AttachmentDTO.entityName)
+        request.sortDescriptors = [NSSortDescriptor(keyPath: \AttachmentDTO.id, ascending: true)]
+        request.predicate = NSPredicate(format: "localStateRaw == %@", LocalAttachmentState.downloaded.rawValue)
+        return load(by: request, context: context)
+    }
 }
 
 extension AttachmentDTO: EphemeralValuesContainer {
@@ -161,6 +175,10 @@ extension NSManagedObjectContext: AttachmentDatabaseSession {
     func delete(attachment: AttachmentDTO) {
         delete(attachment)
     }
+
+    func allLocallyDownloadedAttachments() -> [AttachmentDTO] {
+        AttachmentDTO.loadAllDownloadedAttachments(context: self)
+    }
 }
 
 private extension AttachmentDTO {

Sources/StreamChat/Database/DatabaseContainer.swift

@@ -340,6 +340,14 @@ class DatabaseContainer: NSPersistentContainer {
                         context.reset()
                     }
                 }
+
+                if FileManager.default.fileExists(atPath: URL.streamAttachmentDownloadsDirectory.path) {
+                    do {
+                        try FileManager.default.removeItem(at: .streamAttachmentDownloadsDirectory)
+                    } catch {
+                        log.debug("Failed to remove local downloads", subsystems: .database)
+                    }
+                }
             }
             self?.canWriteData = true
             completion?(lastEncounteredError)

Sources/StreamChat/Database/DatabaseSession.swift

@@ -404,6 +404,9 @@ protocol AttachmentDatabaseSession {
     /// Deletes the provided dto from a database
     /// - Parameter attachment: The DTO to be deleted
     func delete(attachment: AttachmentDTO)
+
+    /// All the attachments with the local status being downloaded.
+    func allLocallyDownloadedAttachments() -> [AttachmentDTO]
 }
 
 protocol QueuedRequestDatabaseSession {

Sources/StreamChat/Models/Attachments/ChatMessageFileAttachment.swift

@@ -79,7 +79,7 @@ extension FileAttachmentPayload: Decodable {
 
 extension URL {
     /// The directory URL for attachment downloads.
-    public static var streamAttachmentDownloadsDirectory: URL {
+    static var streamAttachmentDownloadsDirectory: URL {
         (FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first ?? FileManager.default.temporaryDirectory)
             .appendingPathComponent("AttachmentDownloads", isDirectory: true)
     }

Sources/StreamChat/StateLayer/Chat.swift

@@ -363,11 +363,22 @@ public class Chat {
     /// - Note: The local storage URL can change between app launches.
     ///
     /// - Parameter attachmentId: The id of the attachment.
+    ///
+    /// - Throws: An error while downloading an attachment.
     /// - Returns: An instance of the downloaded file attachment.
     @discardableResult public func downloadAttachment(with attachmentId: AttachmentId) async throws -> ChatMessageFileAttachment {
         try await messageUpdater.downloadAttachment(with: attachmentId)
     }
 
+    /// Deletes the locally downloaded file.
+    ///
+    /// - Parameter attachmentId: The id of the attachment.
+    ///
+    /// - Throws: An error while deleting a downloaded file.
+    public func deleteLocalAttachmentDownload(for attachmentId: AttachmentId) async throws {
+        try await messageUpdater.deleteLocalAttachmentDownload(for: attachmentId)
+    }
+
     /// Resends a failed attachment.
     ///
     /// - Parameter attachmentId: The id of the attachment.

Sources/StreamChat/StateLayer/ConnectedUser.swift

@@ -176,6 +176,17 @@ public final class ConnectedUser {
         try await userUpdater.unflag(userId)
     }
 
+    // MARK: Managing Local Attachment Downloads
+
+    /// Deletes all the local downloads of file attachments.
+    ///
+    /// - Parameter completion: Called when files have been deleted or when an error occured.
+    ///
+    /// - Throws: An error while deleting local downloads.
+    public func deleteAllAttachmentLocalDownloads() async throws {
+        try await currentUserUpdater.deleteAllAttachmentLocalDownloads()
+    }
+
     // MARK: - Private
 
     private func currentUserId() throws -> UserId {

Sources/StreamChat/Workers/CurrentUserUpdater.swift

@@ -155,6 +155,33 @@ class CurrentUserUpdater: Worker {
             }
         }
     }
+
+    func deleteAllAttachmentLocalDownloads(completion: @escaping (Error?) -> Void) {
+        database.write({ session in
+            // Try to delete all the local files even when one of them happens to fail.
+            var latestError: Error?
+            let attachments = session.allLocallyDownloadedAttachments()
+            for attachment in attachments {
+                if let localRelativePath = attachment.localRelativePath {
+                    let localURL = ChatMessageFileAttachment.localStorageURL(forRelativePath: localRelativePath)
+                    if FileManager.default.fileExists(atPath: localURL.path) {
+                        do {
+                            try FileManager.default.removeItem(at: localURL)
+                        } catch {
+                            latestError = error
+                        }
+                    }
+                }
+                attachment.localState = nil
+                attachment.localRelativePath = nil
+                attachment.localState = nil
+                attachment.localURL = nil
+            }
+            log.info("Deleted local downloads for number of attachments: \(attachments.count)", subsystems: .database)
+            guard let latestError else { return }
+            throw latestError
+        }, completion: completion)
+    }
 
     /// Marks all channels for a user as read.
     /// - Parameter completion: Called when the API call is finished. Called with `Error` if the remote update fails.
@@ -224,6 +251,14 @@ extension CurrentUserUpdater {
         }
     }
 
+    func deleteAllAttachmentLocalDownloads() async throws {
+        try await withCheckedThrowingContinuation { continuation in
+            deleteAllAttachmentLocalDownloads() { error in
+                continuation.resume(with: error)
+            }
+        }
+    }
+
     func fetchDevices(currentUserId: UserId) async throws -> [Device] {
         try await withCheckedThrowingContinuation { continuation in
             fetchDevices(currentUserId: currentUserId) { result in

Sources/StreamChat/Workers/MessageUpdater.swift

@@ -574,6 +574,8 @@ class MessageUpdater: Worker {
         }
     }
 
+    // MARK: - Attachments
+
     static let minSignificantDownloadingProgressChange: Double = 0.01
 
     func downloadAttachment(
@@ -613,6 +615,23 @@ class MessageUpdater: Worker {
         }
     }
 
+    func deleteLocalAttachmentDownload(for attachmentId: AttachmentId, completion: @escaping (Error?) -> Void) {
+        database.write({ session in
+            let dto = session.attachment(id: attachmentId)
+            guard let attachment = dto?.asAnyModel() else {
+                throw ClientError.AttachmentDoesNotExist(id: attachmentId)
+            }
+            guard attachment.downloadingState?.state == .downloaded else { return }
+            guard let localURL = attachment.downloadingState?.localFileURL else { return }
+            guard FileManager.default.fileExists(atPath: localURL.path) else { return }
+            try FileManager.default.removeItem(at: localURL)
+            dto?.localState = nil
+            dto?.localRelativePath = nil
+            dto?.localState = nil
+            dto?.localURL = nil
+        }, completion: completion)
+    }
+
     private func fileAttachment(with attachmentId: AttachmentId, completion: @escaping (Result<ChatMessageFileAttachment, Error>) -> Void) {
         database.read({ session in
             guard let attachment = session.attachment(id: attachmentId)?.asAnyModel() else {
@@ -666,6 +685,8 @@ class MessageUpdater: Worker {
             attachmentDTO.localState = .pendingUpload
         }, completion: completion)
     }
+
+    // MARK: -
 
     /// Updates local state of the message with provided `messageId` to be enqueued by message sender background worker.
     /// - Parameters:
@@ -1011,6 +1032,14 @@ extension MessageUpdater {
         }
     }
 
+    func deleteLocalAttachmentDownload(for attachmentId: AttachmentId) async throws {
+        try await withCheckedThrowingContinuation { continuation in
+            deleteLocalAttachmentDownload(for: attachmentId) { error in
+                continuation.resume(with: error)
+            }
+        }
+    }
+
     func deleteMessage(messageId: MessageId, hard: Bool) async throws {
         try await withCheckedThrowingContinuation { continuation in
             deleteMessage(messageId: messageId, hard: hard) { error in

Sources/StreamChatUI/ChatMessageList/ChatMessageListVC.swift

@@ -998,7 +998,7 @@ open class ChatMessageListVC: _ViewController,
             let chat = client.makeChat(for: attachment.id.cid)
             _Concurrency.Task {
                 do {
-                    try await chat.downloadAttachment(attachment.id)
+                    try await chat.downloadAttachment(with: attachment.id)
                 } catch {
                     log.debug("Downloaded attachment for id \(attachment.id)")
                 }