Integrate lifecycle manager into existing room operations

Replace the existing temporary implementations of room attach / detach /
status with those provided by the room lifecycle manager.

Part of #47.

Author: lawrence-forooghian

Sources/AblyChat/ChatClient.swift

@@ -20,7 +20,8 @@ public actor DefaultChatClient: ChatClient {
         self.realtime = realtime
         self.clientOptions = clientOptions ?? .init()
         logger = DefaultInternalLogger(logHandler: self.clientOptions.logHandler, logLevel: self.clientOptions.logLevel)
-        rooms = DefaultRooms(realtime: realtime, clientOptions: self.clientOptions, logger: logger)
+        let roomLifecycleManagerFactory = DefaultRoomLifecycleManagerFactory()
+        rooms = DefaultRooms(realtime: realtime, clientOptions: self.clientOptions, logger: logger, lifecycleManagerFactory: roomLifecycleManagerFactory)
     }
 
     public nonisolated var connection: any Connection {

Sources/AblyChat/DefaultRoomLifecycleContributor.swift

@@ -0,0 +1,48 @@
+import Ably
+
+internal actor DefaultRoomLifecycleContributor: RoomLifecycleContributor {
+    internal let channel: DefaultRoomLifecycleContributorChannel
+    internal let feature: RoomFeature
+
+    internal init(channel: DefaultRoomLifecycleContributorChannel, feature: RoomFeature) {
+        self.channel = channel
+        self.feature = feature
+    }
+
+    // MARK: - Discontinuities
+
+    internal func emitDiscontinuity(_: ARTErrorInfo) {
+        // TODO: https://github.com/ably-labs/ably-chat-swift/issues/47
+    }
+}
+
+internal final class DefaultRoomLifecycleContributorChannel: RoomLifecycleContributorChannel {
+    private let underlyingChannel: any RealtimeChannelProtocol
+
+    internal init(underlyingChannel: any RealtimeChannelProtocol) {
+        self.underlyingChannel = underlyingChannel
+    }
+
+    internal func attach() async throws(ARTErrorInfo) {
+        try await underlyingChannel.attachAsync()
+    }
+
+    internal func detach() async throws(ARTErrorInfo) {
+        try await underlyingChannel.detachAsync()
+    }
+
+    internal var state: ARTRealtimeChannelState {
+        underlyingChannel.state
+    }
+
+    internal var errorReason: ARTErrorInfo? {
+        underlyingChannel.errorReason
+    }
+
+    internal func subscribeToState() async -> Subscription<ARTChannelStateChange> {
+        // TODO: clean up old subscriptions (https://github.com/ably-labs/ably-chat-swift/issues/36)
+        let subscription = Subscription<ARTChannelStateChange>(bufferingPolicy: .unbounded)
+        underlyingChannel.on { subscription.emit($0) }
+        return subscription
+    }
+}

Sources/AblyChat/Room.swift

@@ -19,7 +19,7 @@ public protocol Room: AnyObject, Sendable {
     var options: RoomOptions { get }
 }
 
-public struct RoomStatusChange: Sendable {
+public struct RoomStatusChange: Sendable, Equatable {
     public var current: RoomStatus
     public var previous: RoomStatus
 
@@ -29,7 +29,7 @@ public struct RoomStatusChange: Sendable {
     }
 }
 
-internal actor DefaultRoom: Room {
+internal actor DefaultRoom<LifecycleManagerFactory: RoomLifecycleManagerFactory>: Room where LifecycleManagerFactory.Contributor == DefaultRoomLifecycleContributor {
     internal nonisolated let roomID: String
     internal nonisolated let options: RoomOptions
     private let chatAPI: ChatAPI
@@ -39,21 +39,17 @@ internal actor DefaultRoom: Room {
     // Exposed for testing.
     private nonisolated let realtime: RealtimeClient
 
-    /// The channels that contribute to this room.
-    private let channels: [RoomFeature: RealtimeChannelProtocol]
+    private let lifecycleManager: any RoomLifecycleManager
 
     #if DEBUG
         internal nonisolated var testsOnly_realtime: RealtimeClient {
             realtime
         }
     #endif
 
-    internal private(set) var status: RoomStatus = .initialized
-    // TODO: clean up old subscriptions (https://github.com/ably-labs/ably-chat-swift/issues/36)
-    private var statusSubscriptions: [Subscription<RoomStatusChange>] = []
     private let logger: InternalLogger
 
-    internal init(realtime: RealtimeClient, chatAPI: ChatAPI, roomID: String, options: RoomOptions, logger: InternalLogger) async throws {
+    internal init(realtime: RealtimeClient, chatAPI: ChatAPI, roomID: String, options: RoomOptions, logger: InternalLogger, lifecycleManagerFactory: LifecycleManagerFactory) async throws {
         self.realtime = realtime
         self.roomID = roomID
         self.options = options
@@ -64,7 +60,13 @@ internal actor DefaultRoom: Room {
             throw ARTErrorInfo.create(withCode: 40000, message: "Ensure your Realtime instance is initialized with a clientId.")
         }
 
-        channels = Self.createChannels(roomID: roomID, realtime: realtime)
+        let channels = Self.createChannels(roomID: roomID, realtime: realtime)
+        let contributors = Self.createContributors(channels: channels)
+
+        lifecycleManager = await lifecycleManagerFactory.createManager(
+            contributors: contributors,
+            logger: logger
+        )
 
         messages = await DefaultMessages(
             channel: channels[.messages]!,
@@ -75,12 +77,20 @@ internal actor DefaultRoom: Room {
     }
 
     private static func createChannels(roomID: String, realtime: RealtimeClient) -> [RoomFeature: RealtimeChannelProtocol] {
-        .init(uniqueKeysWithValues: [RoomFeature.messages, RoomFeature.typing, RoomFeature.reactions].map { feature in
+        .init(uniqueKeysWithValues: [RoomFeature.messages].map { feature in
             let channel = realtime.getChannel(feature.channelNameForRoomID(roomID))
+
             return (feature, channel)
         })
     }
 
+    private static func createContributors(channels: [RoomFeature: RealtimeChannelProtocol]) -> [DefaultRoomLifecycleContributor] {
+        channels.map { entry in
+            let (feature, channel) = entry
+            return .init(channel: .init(underlyingChannel: channel), feature: feature)
+        }
+    }
+
     public nonisolated var presence: any Presence {
         fatalError("Not yet implemented")
     }
@@ -98,44 +108,22 @@ internal actor DefaultRoom: Room {
     }
 
     public func attach() async throws {
-        for channel in channels.map(\.value) {
-            do {
-                try await channel.attachAsync()
-            } catch {
-                logger.log(message: "Failed to attach channel \(channel), error \(error)", level: .error)
-                throw error
-            }
-        }
-        transition(to: .attached)
+        try await lifecycleManager.performAttachOperation()
     }
 
     public func detach() async throws {
-        for channel in channels.map(\.value) {
-            do {
-                try await channel.detachAsync()
-            } catch {
-                logger.log(message: "Failed to detach channel \(channel), error \(error)", level: .error)
-                throw error
-            }
-        }
-        transition(to: .detached)
+        try await lifecycleManager.performDetachOperation()
     }
 
     // MARK: - Room status
 
-    internal func onStatusChange(bufferingPolicy: BufferingPolicy) -> Subscription<RoomStatusChange> {
-        let subscription: Subscription<RoomStatusChange> = .init(bufferingPolicy: bufferingPolicy)
-        statusSubscriptions.append(subscription)
-        return subscription
+    internal func onStatusChange(bufferingPolicy: BufferingPolicy) async -> Subscription<RoomStatusChange> {
+        await lifecycleManager.onChange(bufferingPolicy: bufferingPolicy)
     }
 
-    /// Sets ``status`` to the given status, and emits a status change to all subscribers added via ``onStatusChange(bufferingPolicy:)``.
-    internal func transition(to newStatus: RoomStatus) {
-        logger.log(message: "Transitioning to \(newStatus)", level: .debug)
-        let statusChange = RoomStatusChange(current: newStatus, previous: status)
-        status = newStatus
-        for subscription in statusSubscriptions {
-            subscription.emit(statusChange)
+    internal var status: RoomStatus {
+        get async {
+            await lifecycleManager.roomStatus
         }
     }
 }

Sources/AblyChat/RoomFeature.swift

@@ -15,11 +15,7 @@ internal enum RoomFeature {
         case .messages:
             // (CHA-M1) Chat messages for a Room are sent on a corresponding realtime channel <roomId>::$chat::$chatMessages. For example, if your room id is my-room then the messages channel will be my-room::$chat::$chatMessages.
             "chatMessages"
-        case .typing:
-            "typingIndicators"
-        case .reactions:
-            "reactions"
-        case .presence, .occupancy:
+        case .typing, .reactions, .presence, .occupancy:
             // We’ll add these, with reference to the relevant spec points, as we implement these features
             fatalError("Don’t know channel name suffix for room feature \(self)")
         }

Sources/AblyChat/RoomLifecycleManager.swift

@@ -40,7 +40,37 @@ internal protocol RoomLifecycleContributor: Identifiable, Sendable {
     func emitDiscontinuity(_ error: ARTErrorInfo) async
 }
 
-internal protocol RoomLifecycleManager: Sendable {}
+internal protocol RoomLifecycleManager: Sendable {
+    func performAttachOperation() async throws
+    func performDetachOperation() async throws
+    var roomStatus: RoomStatus { get async }
+    func onChange(bufferingPolicy: BufferingPolicy) async -> Subscription<RoomStatusChange>
+}
+
+internal protocol RoomLifecycleManagerFactory: Sendable {
+    associatedtype Contributor: RoomLifecycleContributor
+    associatedtype Manager: RoomLifecycleManager
+
+    func createManager(
+        contributors: [Contributor],
+        logger: InternalLogger
+    ) async -> Manager
+}
+
+internal final class DefaultRoomLifecycleManagerFactory: RoomLifecycleManagerFactory {
+    private let clock = DefaultSimpleClock()
+
+    internal func createManager(
+        contributors: [DefaultRoomLifecycleContributor],
+        logger: InternalLogger
+    ) async -> DefaultRoomLifecycleManager<DefaultRoomLifecycleContributor> {
+        await .init(
+            contributors: contributors,
+            logger: logger,
+            clock: clock
+        )
+    }
+}
 
 internal actor DefaultRoomLifecycleManager<Contributor: RoomLifecycleContributor>: RoomLifecycleManager {
     // MARK: - Constant properties
@@ -615,11 +645,19 @@ internal actor DefaultRoomLifecycleManager<Contributor: RoomLifecycleContributor
 
     // MARK: - ATTACH operation
 
+    internal func performAttachOperation() async throws {
+        try await _performAttachOperation(forcingOperationID: nil)
+    }
+
+    internal func performAttachOperation(testsOnly_forcingOperationID forcedOperationID: UUID? = nil) async throws {
+        try await _performAttachOperation(forcingOperationID: forcedOperationID)
+    }
+
     /// Implements CHA-RL1’s `ATTACH` operation.
     ///
     /// - Parameters:
     ///   - forcedOperationID: Allows tests to force the operation to have a given ID. In combination with the ``testsOnly_subscribeToOperationWaitEvents`` API, this allows tests to verify that one test-initiated operation is waiting for another test-initiated operation.
-    internal func performAttachOperation(testsOnly_forcingOperationID forcedOperationID: UUID? = nil) async throws {
+    private func _performAttachOperation(forcingOperationID forcedOperationID: UUID?) async throws {
         try await performAnOperation(forcingOperationID: forcedOperationID) { operationID in
             try await bodyOfAttachOperation(operationID: operationID)
         }
@@ -727,11 +765,19 @@ internal actor DefaultRoomLifecycleManager<Contributor: RoomLifecycleContributor
 
     // MARK: - DETACH operation
 
+    internal func performDetachOperation() async throws {
+        try await _performDetachOperation(forcingOperationID: nil)
+    }
+
+    internal func performDetachOperation(testsOnly_forcingOperationID forcedOperationID: UUID? = nil) async throws {
+        try await _performDetachOperation(forcingOperationID: forcedOperationID)
+    }
+
     /// Implements CHA-RL2’s DETACH operation.
     ///
     /// - Parameters:
     ///   - forcedOperationID: Allows tests to force the operation to have a given ID. In combination with the ``testsOnly_subscribeToOperationWaitEvents`` API, this allows tests to verify that one test-initiated operation is waiting for another test-initiated operation.
-    internal func performDetachOperation(testsOnly_forcingOperationID forcedOperationID: UUID? = nil) async throws {
+    private func _performDetachOperation(forcingOperationID forcedOperationID: UUID?) async throws {
         try await performAnOperation(forcingOperationID: forcedOperationID) { operationID in
             try await bodyOfDetachOperation(operationID: operationID)
         }

Sources/AblyChat/Rooms.swift

@@ -6,7 +6,7 @@ public protocol Rooms: AnyObject, Sendable {
     var clientOptions: ClientOptions { get }
 }
 
-internal actor DefaultRooms: Rooms {
+internal actor DefaultRooms<LifecycleManagerFactory: RoomLifecycleManagerFactory>: Rooms where LifecycleManagerFactory.Contributor == DefaultRoomLifecycleContributor {
     private nonisolated let realtime: RealtimeClient
     private let chatAPI: ChatAPI
 
@@ -19,14 +19,16 @@ internal actor DefaultRooms: Rooms {
     internal nonisolated let clientOptions: ClientOptions
 
     private let logger: InternalLogger
+    private let lifecycleManagerFactory: LifecycleManagerFactory
 
     /// The set of rooms, keyed by room ID.
-    private var rooms: [String: DefaultRoom] = [:]
+    private var rooms: [String: DefaultRoom<LifecycleManagerFactory>] = [:]
 
-    internal init(realtime: RealtimeClient, clientOptions: ClientOptions, logger: InternalLogger) {
+    internal init(realtime: RealtimeClient, clientOptions: ClientOptions, logger: InternalLogger, lifecycleManagerFactory: LifecycleManagerFactory) {
         self.realtime = realtime
         self.clientOptions = clientOptions
         self.logger = logger
+        self.lifecycleManagerFactory = lifecycleManagerFactory
         chatAPI = ChatAPI(realtime: realtime)
     }
 
@@ -41,7 +43,7 @@ internal actor DefaultRooms: Rooms {
 
             return existingRoom
         } else {
-            let room = try await DefaultRoom(realtime: realtime, chatAPI: chatAPI, roomID: roomID, options: options, logger: logger)
+            let room = try await DefaultRoom(realtime: realtime, chatAPI: chatAPI, roomID: roomID, options: options, logger: logger, lifecycleManagerFactory: lifecycleManagerFactory)
             rooms[roomID] = room
             return room
         }

Sources/AblyChat/SimpleClock.swift

@@ -7,3 +7,9 @@ internal protocol SimpleClock: Sendable {
     /// Behaves like `Task.sleep(nanoseconds:)`. Uses seconds instead of nanoseconds for readability at call site (we have no need for that level of precision).
     func sleep(timeInterval: TimeInterval) async throws
 }
+
+internal final class DefaultSimpleClock: SimpleClock {
+    internal func sleep(timeInterval: TimeInterval) async throws {
+        try await Task.sleep(nanoseconds: UInt64(timeInterval * Double(NSEC_PER_SEC)))
+    }
+}

Tests/AblyChatTests/DefaultChatClientTests.swift

@@ -22,7 +22,7 @@ struct DefaultChatClientTests {
         // Then: Its `rooms` property returns an instance of DefaultRooms with the same realtime client and client options
         let rooms = client.rooms
 
-        let defaultRooms = try #require(rooms as? DefaultRooms)
+        let defaultRooms = try #require(rooms as? DefaultRooms<DefaultRoomLifecycleManagerFactory>)
         #expect(defaultRooms.testsOnly_realtime === realtime)
         #expect(defaultRooms.clientOptions.isEqualForTestPurposes(options))
     }