Add support for sending system messages client-side

CHANGELOG.md

@@ -6,6 +6,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 ## StreamChat
 ### ✅ Added
 - Add support for system messages not updating `channel.lastMessageAt` [#3476](https://github.com/GetStream/stream-chat-swift/pull/3476)
+- Add support for sending system messages client-side
+[#3477](https://github.com/GetStream/stream-chat-swift/pull/3477)
 ### 🐞 Fixed
 - Fix watching channels when performing channel search [#3472](https://github.com/GetStream/stream-chat-swift/pull/3472)
 

DemoApp/StreamChat/Components/DemoChatChannelListRouter.swift

@@ -480,6 +480,15 @@ final class DemoChatChannelListRouter: ChatChannelListRouter {
                     channelController.createNewMessage(text: message, skipPush: true)
                 }
             }),
+            .init(title: "Send system message", isEnabled: canSendMessage, handler: { [unowned self] _ in
+                self.rootViewController.presentAlert(title: "Enter the message text", textFieldPlaceholder: "Send message") { message in
+                    guard let message = message, !message.isEmpty else {
+                        self.rootViewController.presentAlert(title: "Message is not valid")
+                        return
+                    }
+                    channelController.createSystemMessage(text: message)
+                }
+            }),
             .init(title: "Send message without url enriching", isEnabled: canSendMessage, handler: { [unowned self] _ in
                 self.rootViewController.presentAlert(title: "Enter the message text", textFieldPlaceholder: "Send message") { message in
                     guard let message = message, !message.isEmpty else {

Sources/StreamChat/APIClient/Endpoints/Payloads/MessagePayloads.swift

@@ -252,6 +252,10 @@ struct MessageRequestBody: Encodable {
     let id: String
     let user: UserRequestBody
     let text: String
+
+    // Used at the moment only for creating a system a message.
+    let type: String?
+
     let command: String?
     let args: String?
     let parentId: String?
@@ -269,6 +273,7 @@ struct MessageRequestBody: Encodable {
         id: String,
         user: UserRequestBody,
         text: String,
+        type: String? = nil,
         command: String? = nil,
         args: String? = nil,
         parentId: String? = nil,
@@ -285,6 +290,7 @@ struct MessageRequestBody: Encodable {
         self.id = id
         self.user = user
         self.text = text
+        self.type = type
         self.command = command
         self.args = args
         self.parentId = parentId
@@ -312,6 +318,7 @@ struct MessageRequestBody: Encodable {
         try container.encodeIfPresent(pinExpires, forKey: .pinExpires)
         try container.encode(isSilent, forKey: .isSilent)
         try container.encodeIfPresent(pollId, forKey: .pollId)
+        try container.encodeIfPresent(type, forKey: .type)
 
         if !attachments.isEmpty {
             try container.encode(attachments, forKey: .attachments)

Sources/StreamChat/Controllers/ChannelController/ChannelController.swift

@@ -732,7 +732,53 @@ public class ChatChannelController: DataController, DelegateCallable, DataStoreP
             completion: completion
         )
     }
-
+
+    /// Sends a system message to the channel.
+    ///
+    /// - Parameters:
+    ///  - text: The text of the system message.
+    ///  - messageId: The id for the sent message. By default, it is automatically generated by Stream.
+    ///  - extraData: The extra data for the message.
+    ///  - completion: Called when saving the message to the local DB finishes.
+    public func createSystemMessage(
+        text: String,
+        messageId: MessageId? = nil,
+        extraData: [String: RawJSON] = [:],
+        completion: ((Result<MessageId, Error>) -> Void)? = nil
+    ) {
+        guard let cid = cid, isChannelAlreadyCreated else {
+            channelModificationFailed { error in
+                completion?(.failure(error ?? ClientError.Unknown()))
+            }
+            return
+        }
+
+        updater.createNewMessage(
+            in: cid,
+            messageId: messageId,
+            text: text,
+            pinning: nil,
+            isSilent: false,
+            isSystem: true,
+            command: nil,
+            arguments: nil,
+            attachments: [],
+            mentionedUserIds: [],
+            quotedMessageId: nil,
+            skipPush: false,
+            skipEnrichUrl: false,
+            poll: nil,
+            extraData: extraData
+        ) { result in
+            if let newMessage = try? result.get() {
+                self.client.eventNotificationCenter.process(NewMessagePendingEvent(message: newMessage))
+            }
+            self.callback {
+                completion?(result.map(\.id))
+            }
+        }
+    }
+
     /// Creates a new poll.
     ///
     /// - Parameters:
@@ -1285,6 +1331,7 @@ public class ChatChannelController: DataController, DelegateCallable, DataStoreP
             text: text,
             pinning: pinning,
             isSilent: isSilent,
+            isSystem: false,
             command: nil,
             arguments: nil,
             attachments: attachments,

Sources/StreamChat/Database/DTOs/MessageDTO.swift

@@ -38,6 +38,10 @@ class MessageDTO: NSManagedObject {
     @NSManaged var replyCount: Int32
     @NSManaged var extraData: Data?
     @NSManaged var isSilent: Bool
+
+    // Used for creating a message as a system message from the client SDK.
+    @NSManaged var isSystem: Bool
+
     @NSManaged var skipPush: Bool
     @NSManaged var skipEnrichUrl: Bool
     @NSManaged var isShadowed: Bool
@@ -621,6 +625,7 @@ extension NSManagedObjectContext: MessageDatabaseSession {
         mentionedUserIds: [UserId],
         showReplyInChannel: Bool,
         isSilent: Bool,
+        isSystem: Bool,
         quotedMessageId: MessageId?,
         createdAt: Date?,
         skipPush: Bool,
@@ -661,6 +666,10 @@ extension NSManagedObjectContext: MessageDatabaseSession {
         message.parentMessageId = parentMessageId
         message.extraData = try JSONEncoder.default.encode(extraData)
         message.isSilent = isSilent
+        message.isSystem = isSystem
+        if isSystem {
+            message.type = MessageType.system.rawValue
+        }
         message.skipPush = skipPush
         message.skipEnrichUrl = skipEnrichUrl
         message.reactionScores = [:]
@@ -686,9 +695,12 @@ extension NSManagedObjectContext: MessageDatabaseSession {
         message.user = currentUserDTO.user
         message.channel = channelDTO
 
-        let newLastMessageAt = max(channelDTO.lastMessageAt?.bridgeDate ?? createdAt, createdAt).bridgeDate
-        channelDTO.lastMessageAt = newLastMessageAt
-        channelDTO.defaultSortingAt = newLastMessageAt
+        let shouldNotUpdateLastMessageAt = isSystem && channelDTO.config.skipLastMsgAtUpdateForSystemMsg
+        if !shouldNotUpdateLastMessageAt {
+            let newLastMessageAt = max(channelDTO.lastMessageAt?.bridgeDate ?? createdAt, createdAt).bridgeDate
+            channelDTO.lastMessageAt = newLastMessageAt
+            channelDTO.defaultSortingAt = newLastMessageAt
+        }
 
         if let parentMessageId = parentMessageId,
            let parentMessageDTO = MessageDTO.load(id: parentMessageId, context: self) {
@@ -1245,10 +1257,14 @@ extension MessageDTO {
             .sorted { ($0.attachmentID?.index ?? 0) < ($1.attachmentID?.index ?? 0) }
             .compactMap { $0.asRequestPayload() }
 
+        // At the moment, we only provide the type for system messages when creating a message.
+        let systemType = isSystem ? MessageType.system.rawValue : nil
+
         return .init(
             id: id,
             user: user.asRequestBody(),
             text: text,
+            type: systemType,
             command: command,
             args: args,
             parentId: parentMessageId,

Sources/StreamChat/Database/DatabaseSession.swift

@@ -79,6 +79,7 @@ protocol MessageDatabaseSession {
         mentionedUserIds: [UserId],
         showReplyInChannel: Bool,
         isSilent: Bool,
+        isSystem: Bool,
         quotedMessageId: MessageId?,
         createdAt: Date?,
         skipPush: Bool,
@@ -220,6 +221,7 @@ extension MessageDatabaseSession {
         pinning: MessagePinning?,
         quotedMessageId: MessageId?,
         isSilent: Bool = false,
+        isSystem: Bool,
         skipPush: Bool,
         skipEnrichUrl: Bool,
         attachments: [AnyAttachmentPayload] = [],
@@ -239,6 +241,7 @@ extension MessageDatabaseSession {
             mentionedUserIds: mentionedUserIds,
             showReplyInChannel: false,
             isSilent: isSilent,
+            isSystem: isSystem,
             quotedMessageId: quotedMessageId,
             createdAt: nil,
             skipPush: skipPush,

Sources/StreamChat/Database/StreamChatModel.xcdatamodeld/StreamChatModel.xcdatamodel/contents

@@ -208,6 +208,7 @@
         <attribute name="isHardDeleted" attributeType="Boolean" defaultValueString="NO" usesScalarValueType="YES"/>
         <attribute name="isShadowed" attributeType="Boolean" defaultValueString="NO" usesScalarValueType="YES"/>
         <attribute name="isSilent" attributeType="Boolean" usesScalarValueType="YES"/>
+        <attribute name="isSystem" attributeType="Boolean" defaultValueString="NO" usesScalarValueType="YES"/>
         <attribute name="latestReactions" attributeType="Transformable" valueTransformerName="NSSecureUnarchiveFromDataTransformer"/>
         <attribute name="locallyCreatedAt" optional="YES" attributeType="Date" usesScalarValueType="NO"/>
         <attribute name="localMessageStateRaw" optional="YES" attributeType="String"/>

Sources/StreamChat/StateLayer/Chat.swift

@@ -457,6 +457,7 @@ public class Chat {
             text: text,
             pinning: pinning,
             isSilent: silent,
+            isSystem: false,
             command: nil,
             arguments: nil,
             attachments: attachments,
@@ -471,7 +472,41 @@ public class Chat {
         eventNotificationCenter.process(NewMessagePendingEvent(message: localMessage))
         return try await sentMessage
     }
-
+
+    /// Sends a system message to the channel.
+    ///
+    /// - Parameters:
+    ///  - text: Text of the message.
+    ///  - messageId: A custom id for the sent message. By default, it is automatically generated by Stream.
+    ///  - extraData: Additional extra data of the message object.
+    @discardableResult
+    public func sendSystemMessage(
+        with text: String,
+        messageId: MessageId? = nil,
+        extraData: [String: RawJSON] = [:]
+    ) async throws -> ChatMessage {
+        let localMessage = try await channelUpdater.createNewMessage(
+            in: cid,
+            messageId: messageId,
+            text: text,
+            pinning: nil,
+            isSilent: false,
+            isSystem: true,
+            command: nil,
+            arguments: nil,
+            attachments: [],
+            mentionedUserIds: [],
+            quotedMessageId: nil,
+            skipPush: false,
+            skipEnrichUrl: false,
+            extraData: extraData
+        )
+        // Important to set up the waiter immediately
+        async let sentMessage = try await waitForAPIRequest(localMessage: localMessage)
+        eventNotificationCenter.process(NewMessagePendingEvent(message: localMessage))
+        return try await sentMessage
+    }
+
     /// Edits the specified message in the channel.
     ///
     /// - Parameters:

Sources/StreamChat/Workers/ChannelUpdater.swift

@@ -202,6 +202,7 @@ class ChannelUpdater: Worker {
                 id: .newUniqueId,
                 user: user,
                 text: message,
+                type: nil,
                 command: nil,
                 args: nil,
                 parentId: nil,
@@ -285,6 +286,7 @@ class ChannelUpdater: Worker {
     ///   - text: Text of the message.
     ///   - pinning: Pins the new message. Nil if should not be pinned.
     ///   - isSilent: A flag indicating whether the message is a silent message. Silent messages are special messages that don't increase the unread messages count nor mark a channel as unread.
+    ///   - isSystem: A flag indicating whether the message is a system message.
     ///   - attachments: An array of the attachments for the message.
     ///   - quotedMessageId: An id of the message new message quotes. (inline reply)
     ///   - skipPush: If true, skips sending push notification to channel members.
@@ -298,6 +300,7 @@ class ChannelUpdater: Worker {
         text: String,
         pinning: MessagePinning? = nil,
         isSilent: Bool,
+        isSystem: Bool,
         command: String?,
         arguments: String?,
         attachments: [AnyAttachmentPayload] = [],
@@ -323,6 +326,7 @@ class ChannelUpdater: Worker {
                 mentionedUserIds: mentionedUserIds,
                 showReplyInChannel: false,
                 isSilent: isSilent,
+                isSystem: isSystem,
                 quotedMessageId: quotedMessageId,
                 createdAt: nil,
                 skipPush: skipPush,
@@ -673,6 +677,7 @@ class ChannelUpdater: Worker {
                 id: .newUniqueId,
                 user: userRequestBody,
                 text: text,
+                type: nil,
                 extraData: [:]
             )
             return messagePayload
@@ -730,6 +735,7 @@ extension ChannelUpdater {
         text: String,
         pinning: MessagePinning? = nil,
         isSilent: Bool,
+        isSystem: Bool,
         command: String?,
         arguments: String?,
         attachments: [AnyAttachmentPayload] = [],
@@ -746,6 +752,7 @@ extension ChannelUpdater {
                 text: text,
                 pinning: pinning,
                 isSilent: isSilent,
+                isSystem: isSystem,
                 command: command,
                 arguments: arguments,
                 attachments: attachments,

Sources/StreamChat/Workers/MessageUpdater.swift

@@ -230,6 +230,7 @@ class MessageUpdater: Worker {
                 mentionedUserIds: mentionedUserIds,
                 showReplyInChannel: showReplyInChannel,
                 isSilent: isSilent,
+                isSystem: false,
                 quotedMessageId: quotedMessageId,
                 createdAt: nil,
                 skipPush: skipPush,

TestTools/StreamChatTestTools/Mocks/StreamChat/Database/DatabaseSession_Mock.swift

@@ -134,6 +134,7 @@ class DatabaseSession_Mock: DatabaseSession {
         mentionedUserIds: [UserId],
         showReplyInChannel: Bool,
         isSilent: Bool,
+        isSystem: Bool,
         quotedMessageId: MessageId?,
         createdAt: Date?,
         skipPush: Bool,
@@ -155,6 +156,7 @@ class DatabaseSession_Mock: DatabaseSession {
             mentionedUserIds: mentionedUserIds,
             showReplyInChannel: showReplyInChannel,
             isSilent: isSilent,
+            isSystem: isSystem,
             quotedMessageId: quotedMessageId,
             createdAt: createdAt,
             skipPush: skipPush,

TestTools/StreamChatTestTools/Mocks/StreamChat/Workers/ChannelUpdater_Mock.swift

@@ -77,6 +77,7 @@ final class ChannelUpdater_Mock: ChannelUpdater {
     @Atomic var createNewMessage_cid: ChannelId?
     @Atomic var createNewMessage_text: String?
     @Atomic var createNewMessage_isSilent: Bool?
+    @Atomic var createNewMessage_isSystem: Bool?
     @Atomic var createNewMessage_skipPush: Bool?
     @Atomic var createNewMessage_skipEnrichUrl: Bool?
     @Atomic var createNewMessage_command: String?
@@ -343,6 +344,7 @@ final class ChannelUpdater_Mock: ChannelUpdater {
         text: String,
         pinning: MessagePinning?,
         isSilent: Bool,
+        isSystem: Bool,
         command: String?,
         arguments: String?,
         attachments: [AnyAttachmentPayload],
@@ -357,6 +359,7 @@ final class ChannelUpdater_Mock: ChannelUpdater {
         createNewMessage_cid = cid
         createNewMessage_text = text
         createNewMessage_isSilent = isSilent
+        createNewMessage_isSystem = isSystem
         createNewMessage_skipPush = skipPush
         createNewMessage_skipEnrichUrl = skipEnrichUrl
         createNewMessage_command = command

Tests/StreamChatTests/APIClient/Endpoints/ChannelEndpoints_Tests.swift

@@ -268,6 +268,7 @@ final class ChannelEndpoints_Tests: XCTestCase {
             id: .unique,
             user: .dummy(userId: .unique),
             text: .unique,
+            type: nil,
             command: .unique,
             args: .unique,
             parentId: .unique,

Tests/StreamChatTests/APIClient/Endpoints/MessageEndpoints_Tests.swift

@@ -73,6 +73,7 @@ final class MessageEndpoints_Tests: XCTestCase {
             id: .unique,
             user: .init(id: .unique, name: .unique, imageURL: .unique(), extraData: .init()),
             text: .unique,
+            type: nil,
             extraData: [:]
         )